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AutoUI ’26 | Sep 20-23
Gothenburg, Sweden

Main Proceedings:


AutomotiveUI ’26: Proceedings of the 18th International Conference on Automotive User Interfaces and Interactive Vehicular Applications

AutomotiveUI ’26: Proceedings of the 18th International Conference on Automotive User Interfaces and Interactive Vehicular Applications

Full Citation in the ACM Digital Library

SESSION 1: Terrific Takeovers and Colossal Control Transitions

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Autonomy beyond Control: Theory-based Control Allocation for Vehicle Interface Design

  • Dinara Talypova
  • Ambika Shahu
  • Philipp Wintersberger

Research has proposed a variety of cooperative systems that allow drivers to participate in the driving task. While previous work shows that such interfaces can improve user experience, trust, and acceptance, reasons for their effectiveness remain unclear. This paper investigates the effect of different components of autonomy. By operationalizing positive liberty (condition to act upon self-endorsed values) and negative liberty (condition to act without external restrictions) in a vignette study (N=155), we show that differences between automated and manual driving do not emerge from the inherent properties of these concepts but mostly from perceived positive liberty, which seems to be the strongest predictor of willingness to use and psychological need fulfillment. Task allocation and study results indicate that drivers value being included in tactical and strategic decision-making over operational control. These findings suggest that designing for decision authority, rather than control, is key to user acceptance in automated driving.

The Role of NDRT Suspension in Facilitating Safe Control Transitions in Level 3 Automated Cars: Age- and Task-Dependent Insights

  • Rawan Srour Zreik
  • Monika Harvey
  • Stephen Anthony Brewster

Non-Driving-Related Task (NDRT) interruption has been proposed as a strategy to mitigate control-transition challenges in Level 3 cars. However, it remains unclear whether the system should actively suspend ongoing NDRTs. This paper presents the first study to test empirically whether suspending the NDRT at the moment of a Take-Over Request (TOR) improves takeover performance, hazard perception, and user acceptance across three age cohorts (22–32,60–69,70+) in Level 3 cars. Using a driving simulator, participants responded to TORs during high- or low- mental demand NDRTs, under suspension and non-suspension (active) conditions. Suspension consistently reduced reaction times, yet its benefits were uneven: the largest gains appeared in the 70+ and 22–32 groups. The 60–69 group showed limited benefit in both reaction time and hazard perception, suggesting they retained cognitive flexibility. Suspension increased perceived workload under the high-demand NDRT. These findings establish the benefits and limitations of NDRT suspension and call for adaptive TOR design in future vehicles.

Predictability Matters: How Takeover Request Type and Mental Models Shape Trust Development in Real-World Automated Driving

  • Stephanie Seupke
  • Sarukan Segar
  • Martin Baumann

Trust in SAE Level 3 automated driving systems is critical for safe interaction, as drivers must resume control when the system reaches its limits. Trust evolves both over repeated use and in response to situational system behavior, yet the interplay between these dynamics remains insufficiently understood. This longitudinal real-traffic study examined how takeover predictability shapes situational trust, mental model fit, dynamic learned trust, and gaze behavior. Twenty-two drivers completed three weekly sessions using a conditional automated driving system. Subjective measures were collected across sessions and during driving events, complemented by gaze data collected around takeovers. Linear mixed-effects models revealed that sudden takeover requests (TORs) led to significantly lower situational trust compared to announced TORs. Gaze analyses showed limited sensitivity to trust and mental model alignment under high time pressure. These findings highlight the importance of system predictability for trust calibration in automated driving.

The Effect of Task Structure and Monitoring Requests on Take-Over Behavior of Drivers

  • Nicole Damm
  • Marcel Woide
  • Martin Baumann

Automated vehicles require drivers to take over manual control upon receiving a takeover request (TOR). However, drivers often continue performing non-driving related tasks (NDRTs) after a TOR, alternating between the NDRT and driving — a behavior known as interleaving. This study investigated the influence of natural breakpoints (NBs) in NDRTs and of monitoring requests (MRs) on interleaving in a fixed-base driving simulator study (N = 36). Results showed that drivers interrupt NDRTs at NBs in over 90% of cases after a TOR, supporting strategic interruption behavior. However, the number of NBs did not significantly influence interleaving duration or takeover time. Notably, MRs significantly reduced the likelihood of interleaving by 88.83% and improved drivers’ cognitive orientation toward maneuver-relevant areas. These findings suggest that MRs are a promising design measure to reduce interleaving and enhance situational awareness during TORs, contributing to safer human-automation transitions in conditionally automated driving.

The Role of Task Frequency and Complexity in Remote Assistance for Highly Automated Vehicles: Assessing Mental Load based on Eyetracking and Physiology

  • Fabian Walocha
  • Andrea Valerio
  • Hoai Phuong Nguyen
  • Klas Ihme

Guidance through remote assistants (RAs) is a key component for introducing driverless highly automated vehicle fleets (SAE level 4) into future mobility systems. RAs likely encounter situations with variable task demands depending on the frequency of incoming tasks and the complexity of the problems they encounter, potentially inducing mental underload or overload that affect performance during operation. To analyze this, we conducted a simulator study where 19 participants (5 f, 13 m, 1 d) took over the role of RAs for an urban automated shuttle to determine how sensor-based workload prediction can be utilized to differentiate task frequency and complexity variations during remote assistance. Using a gradient boosting classifier, we find that that multi-class multi-output taskload classification using physiology- and eyetracking-based indicators achieves strong results across participants (ROC-AUC – MN: 0.90, SD: 0.07), forming a basis for providing situation-specific adaptive support during remote operation.

SESSION 2: Interaction and Experience in Automated Vehicles

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Comparing Direct and Indirect Passenger In-Car AR Selection Methods for Dense User Interfaces Under Linear Motion

  • Malin Eiband
  • Esteli Garcia
  • Annika Stampf

Augmented reality (AR) glasses have been introduced for passenger use in automotive contexts. However, interaction in moving vehicles is challenging due to physical forces acting on users and spatial constraints. In an on-road study with 23 participants, we compare direct and indirect AR input methods for selection tasks involving dense user interfaces under linear motion. We evaluated two methods in each category: Indirect methods included touch selection and confirmation on a smartphone and on a car-integrated touchscreen. Direct methods included selection using a virtual ray with touch confirmation on a smartphone, and head-based selection with touch confirmation on a smartphone. Our findings indicate that when ergonomically designed, indirect methods are well-suited for in-car AR selections in dense user interfaces, providing faster and more accurate input with lower cognitive load and better usability than direct methods, which were more affected by vehicle motion.

Function v.s. Purpose Oriented UI for Fully Automated Driving: Effects of Task Complexity on Performance, Workload, and Visual Search

  • Subin Jeong
  • Sohyun Park
  • Yein Song
  • Myung Hwan Yun

Fully automated driving shifts occupants from drivers to passengers who can engage in various non-driving-related activities, placing greater demands on UI design. Yet most in-vehicle UIs retain a function-oriented structure for brief and independent interactions, which could be misaligned with scenarios involving sequential chains of non-driving activities in automated driving. We compared function- and purpose-oriented information architectures under low- and high-complexity task conditions in a simulated fully automated driving environment. Thirty-two participants evaluated two UI prototypes under four conditions. Results revealed that information architecture and task complexity influenced user experience through distinct mechanisms: architecture more strongly shaped navigation efficiency and perceived workload, while task complexity predominantly drove attentional demands. The navigational advantage of the purpose-oriented UI increased under the high-complexity condition, suggesting that architecture design becomes increasingly consequential as sequential task demands grow. These findings offer implications for designing cognitively sustainable in-vehicle UIs for the higher task-complexity demands of fully automated driving.

From Assistance to Affective Co-Driving: Novice Drivers’ Emotional Needs and Design Expectations for In-Vehicle AI Agents

  • Wei Gong
  • Mingyuan Zhang
  • Meichen Liu
  • Stephen Jia Wang

As AI becomes increasingly embedded in intelligent cockpits, human-vehicle interaction is shifting from task assistance toward affective and collaborative driving experiences. Yet little is known about what emotional support drivers expect from in-vehicle AI agents or how these expectations can inform design. We conducted semi-structured interviews with 22 novice drivers and a follow-up evaluation with four experts from relevant domains. Thematic analysis identified six design dimensions spanning interaction modality, agent persona, feedback strategy, contextual adaptation, system transparency, and personalization. Participants expected AI agents to combine safety-critical guidance with emotionally calibrated support, including adaptive voice tone, multimodal prompts, explainable interventions, privacy-aware sensing, and roles that evolve from coach to companion. Based on these findings, we propose HACoD, a Human–Agent Emotional Co-Driving Framework that links driver emotional needs, human–agent collaboration patterns, and affective agent design elements. Expert feedback supported the framework’s coherence and design applicability while highlighting the need for transparent data boundaries and real-world validation.

Speak to the City: Multimodal Resolution for Outside-the-Vehicle References

  • Alireza Parchami
  • Artin Saberpour Abadian
  • Robin Connor Schramm
  • Jürgen Steimle
  • Ulrich Schwanecke

As autonomous vehicles and Extended Reality (XR) headsets enable novel in-car interactions, seamlessly querying physical landmarks, known as Outside-the-Vehicle Referencing (OVR), remains challenging due to ego-motion and referential ambiguity. We present a robust, multimodal OVR framework fusing user gaze and natural language to identify Points of Interest (POIs). To address the scarcity of dynamic vehicular data, we developed a VR-based pipeline synchronizing 360-degree transit videos with vehicle GNSS telemetry. Through a user study (N=46) mapping passenger head orientation into a 3D geospatial Digital Twin, we captured authentic gaze-speech behaviors. We subsequently trained a lightweight Transformer network, leveraging LLMs to dynamically align continuous spatial gaze vectors with discrete verbal context. Experimental results demonstrate high accuracy and low computational overhead, achieving an 83.33% Top-1 accuracy (87.72% Top-2) and an average inference time of 24.3 milliseconds. This real-time paradigm effectively resolves referential ambiguity, enabling context-aware spatial retrieval for passengers within the vehicle.

Effects of Auditory Information for People With Visual Impairments in Highly Automated Vehicles

  • Mark Colley
  • Tobias Volkmar Aescht
  • Omid Rajabi
  • Max Rädler
  • Pascal Jansen
  • Enrico Rukzio

Automated vehicles promise to improve accessibility and access to personal mobility for everyone. However, their design and current research trends in visualizing relevant information do not reflect this commitment to accessibility for users with visual impairments. Therefore, we designed and implemented a visual and auditory communication concept for people with visual impairments seated inside fully automated vehicles. Furthermore, in an online video-based study (N=35, 12 with visual impairments), we compared three levels of auditory information communication: low (safety-relevant information only), medium (additionally including vehicle control and route updates), and high (additionally including sightseeing and destination information). Results showed that trust and user experience significantly improved with additional information, with a corresponding, albeit less robust, effect on perceived safety. However, they also revealed that a potential information saturation was reached with medium information. Our work helps to improve the accessibility of automated vehicles by guiding designers towards adequate information communication.

SESSION 3: Driver Support, Safety, and Driving Performance

Session Summary Podcast: Session 3: Driver Support, Safety, and Driving Performance

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I Can See Clearly Now: Co-Designing Augmented Reality Supports for Safer Pedestrian Detection by Older Adult Drivers

  • Paul D. S. Fink
  • Justin R Brown
  • Hassimiou Niane
  • Raina M Movalia
  • Margaret Elizabeth Kastelein
  • Kyle J James
  • Andy Howe
  • Mark Colley
  • Nicholas A Giudice

Older adults face significant challenges with safe driving due to age-related cognitive and sensory decline, particularly in environments with low visibility, which contributes to higher risk of collisions with pedestrians. To address this problem, we present two studies exploring a prototype augmented reality (AR) solution. Study 1 involved a participatory design activity with (N=20) older adults to design AR icons utilized in our prototype solution. A subsequent driving simulator study evaluated our prototype with (N=12) older adults during conditions known to be especially problematic (e.g., at night and during rain). Results suggest participants’ comfort, mental effort, and ability to identify and safely respond to pedestrians were positively impacted by AR support, particularly in low-visibility environments. This work provides preliminary evidence of mixed and extended reality’s potential to support safer driving environments for both older drivers and pedestrians.

Lighting Traffic Ahead: Tunnel Lighting for Hazard Response and Car-Following Safety among Novice Drivers

  • Tianyu Wei
  • Hongling Sheng
  • Dengbo He

Tunnels create a constrained car-following environment in which rear-end crashes remain a major safety concern. This is especially challenging for novice drivers, who may have difficulty anticipating traffic changes further ahead. Existing warning systems mainly reflect the state of the immediate lead vehicle, while vehicle-to-vehicle approaches for upstream information are limited by technology adoption. This paper investigates an infrastructure-based approach that uses ceiling-mounted tunnel lighting to present beyond-visual-range (BVR) traffic information. A driving simulator study with 24 novice drivers was conducted to evaluate two designs: a headway-based representation of traffic spacing (THW-HMI) and a dynamic-state representation of vehicle deceleration (DYN-HMI). The results showed that both HMIs were associated with earlier braking responses, larger temporal safety margins, and lower subjective workload than baseline. Outside the emergency events, car-following behavior remained comparable across conditions. These findings indicate that infrastructure-based ambient cues may contribute to safer tunnel driving for novice drivers.

Inconsistent by Design: A Systematic Review of Experimental Design Practices Across Impaired Driving Domains

  • Kayli Battel
  • John Gideon
  • Megan Applegate-Kenton
  • Patricio Reyes Gomez
  • Anshul Gupta
  • Todd Rowell
  • Thomas M Balch
  • Emily Sarah Sumner
  • Guy Rosman

Impaired driving, including distraction, fatigue, and intoxication, leads to thousands of fatalities annually. Impairment detection and related assistive technologies are rapidly advancing, but their full potential remains unrealized. The inconsistent maturity of impairment research and anomalies within individual domains are key barriers, including variations in taxonomic characterization, experimental data-collection methodologies, and treatment of impairments across studies.

We present a unified review of impairment studies, covering 91 studies across nine impairment domains coded on three dimensions: impairment induction methods, scenario hazards, and observable phenomena and metrics. Our key findings include: (1) a proposed performance-degradation vs. event-response paradigm for existing impairment domains, (2) a maturity framework along the three dimensions, and (3) an analysis of impairment research methodologies, revealing anomalies and gaps in the treatment of scenarios and metrics. We further propose recommendations for standardizing methodologies to support future cross-domain research and development of holistic detection and assistive systems.

Driver Intention Recognition At Urban Intersections: A Real-World Validation of Gaze Shifts

  • Carlotta Mae Mathiske
  • Lukas Leonard Köning
  • Hannah-Leticia Baur
  • Natasa Milicic
  • Martin Baumann

Making maneuver confirmation in Level 2 automated driving seamless means recognizing driver intention without explicit user interaction. To this end, gaze shifts toward a planned trajectory have been established as a behavioral marker for the intention to proceed with a maneuver. This study validates this marker in a real-world setting using eye-tracking data (52 drivers) at urban intersections and characterizes the temporal dynamics of gaze during transitions between three principal intentions: continue unchanged, delay and assess, or proceed with maneuver. We replicated the diagnostic value of gaze shifts: their absence in right-of-way scenarios vs. presence at yielding intersections. We also identified a seven-item temporal sequence from deceleration onset (-6.6 s) to gaze recovery (+4.6 s), with brake release and gaze shift near-simultaneous (-0.8 s relative to decision to proceed). These findings suggest guiding fixation dynamics as a robust base for more intuitive human-integrated Level 2 automated driving frameworks.

The Role of Control: A Driving Simulator Study on User Acceptance of Personalized HMIs for Professional Truck Drivers

  • Anna Eckl
  • Lena Stütz
  • Lara Follert
  • Andreas Riener
  • Klaus Bengler

Professional truck drivers represent a critical yet under-researched user group of automotive human-machine interfaces (HMIs). Adaptive HMIs support decision-making in demanding driving contexts. However, research on adaptive truck HMIs remains limited, particularly regarding adequate user control for expert drivers. To address this gap, we developed an interactive truck HMI prototype providing personalized suggestions. We systematically investigated the level of assistance in a driving simulator study (N = 27), comparing a manual baseline (M), adaptive suggestions with manual choice (AM), and an autonomous adaptive condition (AA). Results show that the personalized suggestions were well accepted, while indicating that the concept with user choice (AM) was preferred. Furthermore, higher patronization was significantly associated with lower acceptance. These findings highlight the potential of personalized truck HMIs to improve drivers’ daily work. At the same time, they underscore the importance of considering perceptions of patronization in future research by designing for user-involved adaptivity.

SESSION 4: Automated Vehicle Interaction with Vulnerable Road Users

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Pedestrian Crossing Prediction for Automated Vehicles: A Geometry-aware Method Using Surface Normal

  • Ali Eskandari
  • Mahdi Rezaei
  • Mohsen Azarmi
  • Derek R Magee

Accurate prediction of pedestrian crossing intention is critical for the safety of automated vehicles. Existing approaches mainly rely on visual appearance and scene context derived from raw images and semantic segmentation. We propose a geometry-aware framework that incorporates surface normal maps encoding pixel-level 3D surface orientation. To integrate heterogeneous information, we extend a multi-stream GRU–attention architecture with surface-normal features. The visual branch combines surface normals, local context, and segmentation overlays, while the non-visual branch includes body pose, bounding boxes, and ego-vehicle speed. Extensive ablation studies on the PIE dataset demonstrate that surface normal maps provide consistent performance gains. When combined with contextual features, they improve F1 score and AUC by 3.85% and 2.35%, respectively, and yield more stable predictions up to two seconds before crossing events. These results highlight the importance of geometry-informed features as an effective complement to conventional visual inputs.

Hit and Run: Evaluating Interface Placements for Automated Vehicle-Runner Interaction

  • Ammar Al-Taie
  • Hyunyoung Han
  • Mingyu Han
  • Ian Oakley

AutomotiveUI research has increasingly explored interfaces for automated vehicles (AVs) to explicitly communicate their yielding intentions and resolve space-sharing conflicts with surrounding road users. However, the focus was primarily on walking pedestrians, overlooking runners, who have distinct requirements. In our outdoor study, participants used an augmented reality simulator to navigate a virtual crossing while running. An AV approached and communicated its intentions using red (not-yielding) / green (yielding) signals across: No-Interface, Smartwatch, eHMI, and Road Projections. No-Interface consistently underperformed. The Smartwatch required sustained attention, distracting runners from the road and hindering their movement. The eHMI required the closest proximity to the vehicle, resulting in delayed interpretation and overreliance on the display vs vehicle behaviour. In contrast, Road Projections were viewable through quick glances without diverting attention; runners still considered AV behaviour, mitigating risky crossing decisions. Our results are crucial for promoting public health and AV interface inclusivity beyond walking pedestrians.

A Systematic Review of VR-Based Studies on Pedestrian Interaction with eHMI-Equipped Automated Vehicles: From Simplified Paradigms to Social Contexts

  • Tianying Guo
  • Chen Peng
  • Andrew Morris
  • Gary Burnett

With the advancement of automated vehicles (AVs), ensuring safe interaction between pedestrians and AVs become a critical challenge. External human–machine interfaces (eHMIs) have emerged as a solution for communicating vehicle intentions to pedestrians. In recent years, virtual reality (VR) has been increasingly used in this research area because of its safety, cost-effectiveness, and high level of experimental control. To synthesise current research trends and identify emerging gaps, this paper systematically reviews 22 VR-based studies on pedestrian interaction with eHMI-equipped AVs published between 2009 and 2025. The results show that VR-based pedestrian-AV research has gradually shifted from simplified, one-to-one interaction paradigms toward more complex experimental designs that incorporate complex traffic environments, diverse participant characteristics, various vehicle settings and eHMI designs. The review identifies an emerging focus on the social context of multi-pedestrian scenarios and its influence on pedestrian crossing behaviour, highlighting VR’s potential for studying such behavioural interactions.

Left at the kerb: A Systematic Review of eHMI Evaluations for Underrepresented VRUs — Children, Older Adults, and People with Disabilities

  • Benjamin Wj Kwok
  • Thomas Goodge
  • Ryan Y. H. Sim
  • Kan Chen
  • Jeannie S.A. Lee

As autonomous vehicles (AVs) become increasingly integrated into traffic environments, external human–machine interfaces (eHMIs) have gained attention for supporting interactions with vulnerable road users (VRUs). This PRISMA-guided systematic review examines 20 peer-reviewed studies published between 2015 and 2025, focusing on the methodologies, evaluation tools, and participant engagement practices used in eHMI research involving children, older adults, and persons with disabilities (PwDs), referred to as Especially Vulnerable Road Users (EVRUs). The findings indicate group-linked differences in methodological approaches. Immersive simulations were commonly used in studies involving children and older adults, while co-design and participatory approaches were more prevalent in studies involving PwDs. The inconsistency across studies restricts direct comparison and makes it difficult to draw firm conclusions about effective development and evaluation practices or interface outcomes. By mapping current approaches and methodological gaps, the review identifies opportunities for more consistent, inclusive, and transparent practices in future eHMI research and development.

Designing for Anticipation: Centring Cyclist Perspectives on Trust for Automated Vehicle Interaction

  • Jumana Baghabrah
  • Lars Kunze
  • Marina Denise Jirotka

As automated vehicles (AVs) become increasingly present on public roads, they introduce new challenges for vulnerable road users (VRUs), such as cyclists. We report findings from a qualitative diary study with (N = 90) cyclists in Brazil, using reflections on everyday interactions with conventional vehicles to inform the design of future cyclist-AV interactions. Our analysis suggests that anticipation provides a useful interpretive lens for understanding how cyclists coordinate traffic interactions. Cyclists continually integrate cues, social consideration, and contextual resources to develop reliable expectations about how interactions will unfold. Building on this perspective, we derive design considerations for cyclist-AV interaction, identify an overlooked perspective in AV trust research concerning secondary road users, and outline directions for investigating anticipation as a mechanism for evaluating AV interaction design across diverse traffic contexts.

SESSION 5: Human Behaviour and Interaction in Emerging Urban Mobility

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+Walk: A Proof-of-Concept System for Exploratory Walking

  • Tomosuke Maeda
  • Keisuke Otaki
  • Takayoshi Yoshimura
  • Hiroyuki Sakai
  • Kouta Minamizawa

We propose +Walk, a concept that uses spare time before reaching a destination as an opportunity for exploratory walking under arrive-by constraints. To realize this concept, we built the +Walk system, a proof-of-concept implementation that combines time-budgeted routing with handheld pseudo-force haptic guidance. The routing method supports small detours while keeping arrival close to the planned time, and the haptic device provides turn-by-turn cues through pseudo-force sensations. In an outdoor evaluation, haptic guidance reduced phone-focused gaze and increased enjoyment and awareness of surroundings, while screen-based navigation was easier to interpret, felt more reliable, and produced fewer navigation errors. In a proof-of-concept field validation, participants arrived within user-acceptable tolerances and preferred +Walk in situations with spare time and low time pressure. These findings suggest that +Walk can support exploratory walking as a meaningful, context-dependent walking segment within multimodal mobility.

Prosocial Interaction in Mixed Traffic: How Human Involvement and Traffic Density Influence Road User Behavior

  • Md Akib Shahriar Khan
  • Shadan Sadeghian

Prosocial traffic interaction occurs when road users prioritize others’ intentions, needs, or vulnerability. As automated vehicles (AVs) enter everyday traffic, they introduce new forms of human-AV coexistence that make prosociality harder to enact, interpret, and expect in mixed traffic. Prior work has studied interaction with AVs through intention communication and coordination, offering less insight into what motivates prosocial behavior and toward whom it is directed. To address this gap, we conducted an ideation workshop(n=12) and a 2×3×2 vignette study(n=100) investigating the effects of role, human involvement, and traffic density on the expectation and enactment of prosocial behavior. Results showed that prosociality is human-centered, with road users most likely to enact prosocially when a human was involved in control of the vehicle or directly affected by the interaction, particularly in high-density traffic. Finally, we derive implications on AVs communicating awareness of human social cues to sustain prosocial interaction in mixed traffic.

Vibrotactile Navigation for E-Scooters in an Outdoor Riding Experiment

  • Tomosuke Maeda
  • Keisuke Otaki
  • Takayoshi Yoshimura
  • Tomoaki Mitsuhashi
  • Takafumi Horigome
  • Hiroyuki Sakai

E-scooter riders often look away from the road to check smartphone navigation, increasing visual distraction. We investigated whether handlebar-mounted vibrotactile cues can reduce eyes-off-road behavior during outdoor riding. In an on-campus study, 14 first-time users of haptic navigation completed a Visual condition (baseline) and a combined Haptic condition using Google Maps turn prompts. We measured route following, smartphone-directed eyes-off-road events, workload, usability, and post-trial feedback. The Haptic condition significantly reduced eyes-off-road behavior, while workload and usability remained comparable. Preliminary road-noise (road-induced vibration) measurements suggest that an approximately 240 Hz cue was suitable on the normal pavement route, but prompt timing, brief hand-release moments, and road-noise masking limited performance in some situations. These findings suggest that handlebar haptics can support outdoor e-scooter navigation, while also highlighting the need for more robust cue timing and cue design under route-dependent constraints.

AI Eyes on the Road: Cross-Cultural Perspectives on Traffic Surveillance

  • Ziming Wang
  • Shiwei Yang
  • Rebecca Currano
  • Morten Fjeld
  • David Sirkin

AI-powered road surveillance systems are increasingly proposed to monitor infractions such as speeding, phone use, and jaywalking. While these systems promise to enhance safety by discouraging dangerous behaviors, they also raise concerns about privacy, fairness, and potential misuse of personal data. Yet empirical research on how people perceive AI-enhanced monitoring of public spaces remains limited. We conducted an online survey (N = 720) using a 3×3 factorial design to examine perceptions of three road surveillance modes—conventional, AI-enhanced, and AI-enhanced with public shaming—across China, Europe, and the United States. We measured perceived capability, risk, transparency, and acceptance. Results show that conventional surveillance was most preferred, while public shaming was least preferred across all regions. Chinese respondents, however, expressed significantly higher acceptance of AI-enhanced modes than Europeans or Americans. Our findings highlight the need to account for context, culture, and social norms when considering AI-enhanced monitoring, as these shape trust, comfort, and overall acceptance.

Impact of Finger Modality on the Effectiveness, Safety, and Comfort of Touchscreen Interaction in Frugal LEVs

  • Mateo Jukic
  • Peter Mörtl

The automotive industry’s shift toward frugal Light Electric Vehicles (LEVs) replaces physical controls with portrait-oriented touchscreens. Unlike conventional touchscreens requiring a “loose” index finger, these screens afford an “anchored” thumb posture where users grip the bezel. We conducted a driving simulator study (N = 31) evaluating Finger Modality (thumb versus index), Button Size, and Road Complexity (straight versus curve) to assess this novel interaction’s safety and ergonomics. Results revealed a trade-off: the anchored thumb’s stabilization enabled a “press by feel” strategy, significantly reducing visual demand during curves. Conversely, the index finger yielded faster reaction times on straight roads but neither finger modality significantly compromised overall steering stability during interactions. Furthermore, while larger buttons (≥ 17.5mm) universally improved driving performance, scaling buttons too large introduced biomechanical reach constraints for the anchored thumb. To safely deploy frugal touchscreens, designers must carefully balance minimum button sizes with the physical reach of the thumb.

SESSION 6: Computational Modeling, Methods and Tools

The Best of Both Worlds? The Validity of Mixed-Reality Vehicles for Human-Centered Automotive Research

  • Chantal Himmels
  • Paula Santos
  • Kai Liu
  • Lukas Leonard Köning
  • Dennis Lenz

Over the past decades, driving simulators have undergone rapid improvements but remain limited by their restricted motion space, preventing a full replication of real driving sensations. Mixed-Reality Vehicles (MRVs), which combine a real car with a virtual environment via a head-mounted display, offer a promising alternative with enhanced physical validity. This study compared three test environments — real traffic, an MRV setup, and a high-fidelity driving simulator — in evaluating a novel driver assistance system. Both MRV and driving simulator demonstrated absolute validity in measuring cognitive load and acceptance (usefulness) of the system. While the driving simulator generally performed well, the MRV provided valid results across more variables. Additionally, there was no simulator sickness at all in the MRV. Researchers should weigh the benefits against the extra effort required for MRV studies. The presented findings may not generalize to lower-quality simulators.

VideoSimLab: Developing a Video-Based Toolchain for Vehicle Display Evaluation Studies

  • Jan Heidinger
  • Leonardt Wagner
  • Christopher Spölmink
  • Thomas Franke

Driving simulators are the de facto standard to evaluate vehicle displays under controlled conditions, yet each participant occupies one lab at a time, limiting throughput for tasks such as iterative design evaluation. Video-based studies can address this, but accessible toolchains for cockpit display evaluation are not readily available. We present VideoSimLab, an open-source toolchain that renders cockpit displays dynamically on pre-recorded driving videos with synchronized vehicle data, so a single recording can serve any number of interface conditions. We derived requirements from a review of video-based automotive UI studies. Three proof-of-concept studies focused on (S1) questionnaire-based acceptance measurement, (S2) SAGAT freeze probes for situation awareness assessment, and (S3) a replication study of a driving simulator experiment in VideoSimLab. Results of S3 replicated the primary effect of eco-driving displays on energy-specific situation awareness. All source code, recordings, and driving data are publicly available.

Modeling Driving and Visual Perception through Computational Rationality

  • Alexander Lingler
  • Martin Lorenz
  • Arezoo Sedghi
  • Helena Anna Frijns
  • Bernd Resch
  • Patrick Ebel
  • Philipp Wintersberger

Drivers’ attention allocation plays a critical role in traffic safety, as driving requires the coordination of attention and control under uncertainty. Thus, predicting driving and gaze behavior is essential for automotive interfaces and intelligent vehicle systems. However, prior models typically treat gaze and driving behavior in isolation, failing to capture their interdependence. Consequently, we present a computational-rational model that jointly captures visual scanning and driving. A vision agent allocates gaze to update a belief state, which informs a driving agent controlling driver behavior. The model is based on first principles, modeling vision and eye-movement timing. We evaluated the model in a lane-change task with eye tracking, comparing agent and human behavior. Results show that the model attends to task-relevant regions and shows driving behavior closer to human trajectories when relevant information is sampled. This work contributes a unified, interpretable framework for modeling perception-action coupling in driving under partial observability.

Constrained Generative UI for the Cockpit: A Comparison of LLM-Assembled and Pre-Defined Interfaces

  • Akshil Shah
  • Sebastian Zepf
  • Andreas Riener

In-car infotainment systems are growing in complexity, making traditional design and engineering approaches costly and difficult to scale. Recent advances in large language models (LLMs) offer context-aware, dynamic capabilities, enabling interfaces to adapt in real-time and reducing the need for manual design. We propose a scalable framework for Constrained AI-Assembled Graphical User Interfaces (GUIs) that dynamically assembles the interface at runtime from a pre-validated library of components using an LLM. We evaluated this approach in a comparative user study (N = 30) in a simulated driving environment, measuring usability, as well as driver’s cognitive load, distraction, and situational awareness. Quantitative results showed no significant differences between AI-assembled and conventional pre-designed interfaces regarding usability and driver’s mental state. Our qualitative feedback highlighted occasional challenges in information prioritization. We conclude that AI-assembled GUIs have the potential to achieve performance similar to conventional pre-defined interfaces and provide design recommendations to guide future work.

Multi-Session User Experience Assessments of Computationally Optimized Automated Vehicle Functionality Visualizations

  • Mark Colley
  • Pascal Jansen
  • Svenja Krauß
  • Enrico Rukzio

Understanding automated vehicles (AVs) is crucial to improving their acceptance. Numerous approaches to visualizing relevant traffic information to passengers have been proposed and empirically evaluated. As this is time-consuming, costly, and reduces the possible design parameters, we employed multi-objective Bayesian optimization to optimize the design of visualizations in AVs. In particular, we evaluated multi-session aspects involving iterative optimization. We optimized the design for passenger trust and perceived safety while minimizing cognitive load. Results from an online study (N=74) show that this method effectively identifies visualization design parameter values that improve trust, safety, and predictability while making the design process more efficient and scalable. However, shortcomings of the computational approach when optimizing for subjective measurements are highlighted and discussed.


Adjunct Proceedings:


AutomotiveUI Adjunct ’26: Adjunct Proceedings of the 18th International Conference on Automotive User Interfaces and Interactive Vehicular Applications

AutomotiveUI Adjunct ’26: Adjunct Proceedings of the 18th International Conference on Automotive User Interfaces and Interactive Vehicular Applications

Full Citation in the ACM Digital Library

SESSION: Work in Progress

Evaluating In-Vehicle Interface Potential for Driver Distraction through Hierarchical Task Analysis of Interaction Models

  • Ben Tankersley
  • Missie Smith
  • John Lenneman

The purpose of this research was to understand how an in-vehicle interaction model might impact driver distraction, considering how drivers input information into the vehicle and receive feedback from the vehicle. We conducted a task analysis on five vehicle models to evaluate the demands placed on the driver by the interaction model in that vehicle. Vehicles were selected by targeting different interaction models including designs that were mostly buttons, mostly touchscreen, and combinations thereof. For each vehicle, we collected information about the functions available within the vehicle, how drivers input information into the in-vehicle center console, the types of feedback received from the vehicle, and the steps required to complete each function. We conducted qualitative and quantitative analysis comparing the data from the five vehicles. From this dataset, we explore preliminary insights regarding how interaction models relate to driver demand, which may inform future investigations of in-vehicle information system design.

Interviewing Silicon Experts: A Persona-Based LLM Interview Pipeline in Automated Driving

  • Ying Fang
  • Pavlo Bazilinskyy
  • Marieke Martens

Human expert interviews are valuable but often limited by slow recruitment, scarce expertise, and network-based sampling, especially for abstract human-automation topics requiring multidisciplinary input. This paper presents a persona-based LLM expert-interview pipeline for structuring expert knowledge before human involvement. We constructed 28 discipline-specific personas and purposively selected seven differentiated “silicon experts” across human factors, UX design, algorithm engineering, accident investigation, regulation, accessibility, and product management. Using drivers’ minimum mental model (MMM) as a demonstration topic, each persona completed a structured interview protocol and returned JSON-formatted responses. The pipeline generated 59 candidate items, producing concrete, traceable, and auditable outputs. Results showed both convergence and persona-specific divergence: shared priorities included driver responsibility, operational design domain, and permitted non-driving-related tasks, while divergent contributions highlighted OTA updates, sensor limitations, and warning perceivability. The pipeline is positioned as a preliminary scoping tool for preparing subsequent human expert validation.

Toward Stress-Adaptive AI Coaching: Understanding Driver Stress Under Time Pressure

  • Yudai Shimizu
  • Srijan Srivatsa
  • Zixuan Lao
  • Jean Costa
  • Tiffany L. Chen

Stress-adaptive AI coaching may improve driving performance and experience by tailoring feedback to a driver’s internal state. This study investigated driver stress, driving performance, multimodal sensing, and temporal stress annotations under time pressure in a driving simulator. Participants completed repeated laps under three time-pressure conditions while physiological signals, vehicle telemetry, post-lap stress ratings, and retrospective temporal stress annotations were collected. Results showed that time pressure increased stress ratings, although substantial overlap remained across conditions. Subjective stress was more strongly associated with driving performance and vehicle-control behavior than task condition alone. Analyses stratified by subjective stress ratings suggested that pupil-related measures and driving variability features differentiate stress levels. Temporal annotations aligned with post-lap ratings, supporting their use as proxy labels for within-lap stress dynamics and future real-time stress modeling. These findings inform future stress-adaptive AI coaching systems and adaptive automotive interfaces.

Exploring the Attentional Cost of Visual Motion Sickness Mitigation Strategies in Smart Cabin

  • Jinghao Huang
  • Tianyu Wei
  • Siqi Yao
  • Yu Zhang
  • Dengbo He

Passengers are susceptible to motion sickness (MS) when engaging in non-driving-related tasks (NDRTs) in the cabin. Visual information about ego-vehicle motion can alleviate MS, yet it may also compete for cognitive resources needed for NDRTs, degrading NDRT performance. To reveal the potential negative effects of MS mitigation strategies, we designed two types of visual cues, i.e., implicit dynamic optic flow and explicit predictive symbols, and compared their MS-mitigation effects and impact on NDRT performance. An on-road driving experiment was conducted with 10 participants. Using a high-interaction NDRT, we revealed an NDRT performance degradation effect of a certain MS mitigation interface. Although all visual cues helped mitigate MS, explicit predictive cues significantly impaired task performance (p < 0.05), whereas implicit optic flow alone had minimal impact on NDRT performance. The results indicate that the attentional cost of MS mitigation cues should be carefully evaluated in the smart cabin, highlighting the need to balance sensory comfort with productivity in future intelligent cockpits.

Does the Small Blue Light Matter? Naturalistic Evidence on the Influence of External ADAS Status Signals on Car-Following Behavior

  • Yue Hong
  • Fangning Zhang
  • Xiangyu Li
  • Yonglin Weng
  • Ke Ma
  • Dengbo He

As Advanced Driver Assistance Systems (ADAS) become increasingly common in production vehicles, surrounding drivers may increasingly encounter vehicles whose behavior is partly controlled by automation. In China, some ADAS-supported vehicles use an externally visible indicator, commonly referred to as the “small blue light,” to signal that ADAS is active. However, limited naturalistic evidence is available on whether such external ADAS status visibility influences surrounding drivers. This study investigated following drivers’ car-following behavior in naturalistic traffic when the lead vehicle operated with ADAS activated and the small blue light was on or off. Results showed speed-dependent changes under the blue-light-on condition. In particular, following drivers maintained larger time headway when the lead vehicle traveled at higher speeds with the light on. By providing naturalistic evidence from ADAS-supported production vehicles, this study contributes to understanding how external ADAS status visibility may shape following drivers’ longitudinal driving behaviors in real traffic.

WidgetGNN: Self-Optimizing HMI Layouts with Graph Neural Networks

  • Alexandra Usman
  • Jill Pasch
  • Jens Bartels
  • Svetlana Getmanskaya
  • Klaus Staudenmaier
  • Johannes Oberhofer
  • Jürgen Joos

We present WidgetGNN, a graph neural network–based approach for interactive-speed generation of adaptive human–machine interfaces (HMIs). Widgets are modeled as interacting nodes that iteratively optimize their spatial arrangement. The system combines continuous coordinate updates with a novel swapper network that enables discrete structural adjustments, improving cluster formation and layout quality. Unlike static layouts, WidgetGNN supports dynamic changes such as resizing, addition, and repositioning of widgets while preserving design rules. User experience (UX), brand, and structural rules can be flexibly defined and modified through system settings without requiring changes to the underlying model.

Designing Graceful Degradation for Multimodal Autonomous Vehicle Cabins

  • Yumeng Ma
  • Rani Malhotra

Future autonomous vehicle cabins may function as immersive spaces in which riders rest, work, or watch media while the vehicle manages navigation and control. Hazards create a communication challenge because riders may have little awareness about road conditions when the cabin needs to convey risk. We examine graceful degradation as a design lens for coordinating multimodal cabin responses across changing hazard states. We conducted a storyboard-based study with N = 12 participants who reviewed three scenarios with different time profiles: a gradual snowstorm, an intermediate pedestrian event, and a sudden incoming vehicle. Participants reflected on staged visual, auditory, and haptic cues. They associated graceful responses with cue strength that tracked hazard tempo, visible system intent, restrained haptics, and a prompt return to the baseline cabin state after danger passed. We position graceful degradation as a temporal interaction framework for rider-facing Level 5 autonomous vehicle cabins. We also identify design tensions and next-step studies around escalation thresholds, haptic intensity, sensory load, trust, and emergency cue offset.

Personalised Electric Vehicle Acoustics with Generative AI: A Dynamic Sonification and User Acceptance Study

  • Wessel Verstelle
  • Md Shadab Alam
  • Pavlo Bazilinskyy

Electric vehicles (EVs) reduce powertrain noise, creating safety challenges and opportunities for sound design. This paper examines whether generative audio supports personalised dynamic acoustics for future EVs. We report a research through design study in which AI-generated sound samples were selected, edited into seamless loops and embedded in a sonification (the process of translating non-auditory data into sound) prototype. The prototype connects a Processing vehicle interface to a Pure Data audio engine using Open Sound Control. Vehicle speed and throttle input modulate pitch, amplitude and load related parameters. A user study with 20 participants combined the Acceptance Scale with open questions. The results show moderately positive acceptance, with an average usefulness of 0.88 and a satisfaction of 0.62 on a scale from -2 to +2. Participants valued personalisation and responsiveness, but requested stronger recognisability and better throttle mapping. Generative AI is useful for early EV acoustic prototyping, while the final design requires expert refinement and safety evaluation.

It’s the Dock, Not the Bike: How the Return Maneuver Shapes Affective Impressions and Rental Intention in Shared Micromobility

  • Yong-Yi Cheng
  • An-Pin Chiu
  • Jo-Yu Kuo

The success of sustainable micromobility depends on the rent–ride–return interaction between users and vehicles, yet the design features that underlie affective experience and rental intention remain underexplored. This study compared six morphological variables of shared electric bicycles (frame geometry, frame tube, handlebar curvature, storage placement, dock placement, and interface placement), with perceptual descriptors derived using large language models. To capture effects that emerge only in motion, 30 prototypes spanning these variables were rendered as 5-second animations and rated online (n = 98). Quantification Theory I revealed that dock placement exerted the strongest influence on rental intention, shaping perceptions of “effort-saving” and “lightweight”. A validation experiment partially supported these predictions and indicated that components with negligible perceptual effects can be delegated to generative AI for styling. These findings suggest the return maneuver, a point of infrastructure-vehicle integration governed by docking context, deserves closer design attention in shared micromobility adoption.

What, Why, and Now What: Complaint-Driven Design of Explainable Visual ADAS Alerts

  • Seowoo Kim
  • Taehyun Ha
  • Sangwon Lee

As advanced driver assistance systems (ADAS) become more complex in software-defined vehicles, drivers increasingly rely on visual alerts to understand system states, limitations, and interventions. However, an alert may show that something is wrong without explaining why it appeared or what the driver should do. This work analyzes vehicle-owner complaints from the NHTSA Vehicle Owner Complaint database to identify recurring interpretation breakdowns in visual ADAS alerts. Through a multi-stage filtering pipeline, a rule-based modality tagger, and hierarchical topic modeling, three breakdown mechanisms are identified: missing causal grounds and next steps, fragmented alerts within feature families, and limited transparency during abrupt interventions. These inform design implications for explainable visual ADAS alerts — What–Why–Now What explanations, progressive disclosure across cluster and center displays, and confidence/evidence cues for trust calibration — illustrated through scenarios that adapt explanation density to urgency and criticality.

Preserving the Joy of Driving: A Context-Aware Conversational Companion for Road Trip Enthusiasts

  • Alina Remlinger
  • Alice Rollwagen
  • Andreas Riener

The transition toward highly automated vehicles is primarily driven by safety and efficiency, often overlooking subjective aspects of driving such as enjoyment, emotional engagement, and the pleasure of driving itself. These factors remain central to the mobility experience of drivers. We evaluate a context-sensitive, smartphone-based conversational companion that proactively delivers location-based narrative content through a Wizard-of-Oz setup in a field study (N = 20). To balance exploration with driving safety, conversational interventions were triggered based on contextual factors such as location, the current driving situation and social context. Although the system ranked in the top ten percent for novelty and stimulation in the global metrics of the UEQ, correlation analysis revealed a significant negative correlation with car passion. This suggests that preserving the joy of driving requires personalized conversational agency, where systems must intelligently distinguish between exploratory and performance-oriented driving contexts.

Toward Size-Aware Interaction: Cyclists’ Self-Reported Responses to Differently Sized Vehicles

  • Shuhao Zhang
  • Diego Drago
  • Frank Pollick
  • Stephen Anthony Brewster

As autonomous vehicles (AVs) diversify, cyclists may encounter AVs of different sizes. However, existing research on cyclist-AV has mainly focused on passenger cars and has still lacked cross-size exploration. This work conducted two studies to understand how cyclists currently interact with different-sized vehicles, as a starting point for informing how cross-size AVs should communicate with cyclists. Study 1 (survey N=92; focus groups N=8) derived a cyclist-centred four-category conceptual structure of vehicle size (Small, Medium, Large, Huge). Based on this, Study 2 (N=120) asked cyclists to self-report their perceptions and behavioural tendencies when interacting with different-sized vehicles. We found that larger vehicles were associated with lower perceived safety and stronger preferences for spatial distance. These results provide baseline evidence that vehicle size is a potential factor that influences cycling interactions. Therefore, future studies and designs should more explicitly account for vehicle size.

Evaluating the effects of in‑vehicle infotainment input modalities on driver distraction

  • Anthony Oluwafemi Omoniyi
  • Missie Smith
  • Malek Jaber
  • Robert F Haas
  • John Lenneman

Driver distraction from in-vehicle information systems contributes significantly to road accidents. As physical controls (buttons and dials) are increasingly replaced by touchscreens and touchpads, understanding how different input modalities affect driver distraction and performance becomes critical. This study examines the effects of four input modalities (touchscreen, touchpad, button, and dial) on driver distraction. Thirty-seven participants performed secondary tasks using each input modality while driving in a simulator. Driver distraction was assessed using driving performance metrics, task performance, gaze behavior measures, and subjective ratings. Touchscreen and touchpad use resulted in significantly greater lane position variability than button input. All modalities significantly increased the human-machine interface (HMI) fixation and reduced road fixation relative to baseline driving. These findings indicate that the button condition was associated with favorable usability-related outcomes and may inform future investigations of function allocation in vehicle interface design.

Does Sidewalk Separation Type Matter? How Sidewalk Design Shapes Pedestrian Acceptance of Public Mobile Robots

  • Suhwan Jung
  • Young Woo Kim
  • Kyuho Maeng
  • Jieun Lee
  • Tram Thi Minh Tran
  • Gaojian Huang
  • Seul Chan Lee

Public Mobile Robots (PMRs) are increasingly operating on urban sidewalks, yet the physical design of these shared spaces has received little empirical attention as a determinant of pedestrian acceptance. This work-in-progress paper presents findings from a within-subjects experiment (N = 500) examining how three sidewalk separation types, Shared Space, Semi-separated Space, and Fully-separated Space, affect pedestrian subjective perceptions and coexistence acceptance. The three separation types represent conceptual conditions spanning a spectrum currently under policy and infrastructure discussion across multiple countries, rather than physical designs we implemented or evaluated in situ. Repeated-measures ANOVA revealed that Shared Space consistently produced the least favorable evaluations across all seven measured constructs. Semi-separated and Fully-separated Space conditions yielded comparable outcomes for Perceived Usefulness, Sidewalk Design Acceptance, and Coexistence Intention, suggesting that the presence of any spatial demarcation, rather than its degree, may represent the more consequential factor in early acceptance formation. We discuss what these findings suggest for the design of PMR coexistence environments and identify open questions for future research, including how different forms of spatial demarcation may be experienced across diverse pedestrian populations and real-world deployment contexts.

Human Driver Digital Twins: Definitions, Concepts, Use-Cases, and Engineering Challenges

  • Yannick Naudet
  • Mirko A Ledda
  • Klas Ihme
  • Mark Eilers
  • Fei Yan
  • Christine E Boylan

While the concept of the Human Digital Twin has been proposed within the automotive domain, a structured framework to define and operationalize it is currently lacking. This paper interrogates the concept of Human Driver Digital Twins (HDDTs), systematically distinguishing them from Human Driver Digital Models (HDDMs) and Human Driver Digital Shadows (HDDSs) based on data integration levels and bidirectional feedback loops. We examine a broad spectrum of automotive use cases to assess how the HDDT paradigm can enhance existing applications and where conventional driver modeling methodologies encounter functional limitations. Furthermore, we acknowledge engineering challenges, such as data sovereignty, standardized interaction protocols, and modular internal architectures. Ultimately, this work highlights how an HDDT framework allows systems to transcend the boundaries of static driver modeling, enabling persistent, adaptive, and personalized representations of the human driver.

Sim-DSE: Mediating Multi-User Automations in Cars through Simulation-Augmented Decision Space Exploration

  • Jan Henry Belz
  • Kayoon Kim
  • Enrico Rukzio
  • Tobias Grosse-Puppendahl

In-vehicle interaction is often envisioned as requiring as little explicit user input as possible. In multi-user scenarios, however, varying user states and expectations can lead to conflicting automation scenarios. Including more than one passenger introduces complexity to the interaction space that has been neglected by existing literature. We tackle this with a systematic Simulation-Augmented Decision Space Exploration (Sim-DSE) approach: Relevant in-vehicle interactions are identified in an expert workshop (N = 5) and utilized to model a suitable decision space for in-car automations. We then simulate 1000 permutations in this decision space using an agentic AI framework to derive the reasoning behind these automations. Next, we validate the simulated outcomes and their rationales through human feedback in an online survey (N = 100) and distill the results into design guidelines for multi-user automation. The method and guidelines help future researchers and developers to mitigate automation conflicts in multi-user scenarios.

Exploring a Design Science approach to visualizing complex automotive software architectures

  • Hyosun Kim
  • Yuxin Liu
  • Siddharth Ramesh
  • Renan Guarese

Modern automotive software architectures have evolved into highly complex networks of software components, electronic control units, signals, and thousands of properties. Understanding these multi-format, large-scale, highly-nested software structures is a significant cognitive challenge for domain experts. To address this, this Work-in-Progress paper presents an interactive software visualization artifact developed following the Design Science Research Methodology. The designed artifact ingests heterogeneous automotive vehicle data (ARXML, YAML, and binary files) and establishes a unified pipeline to transform these raw, disconnected metadata into comprehensive network models. By applying knowledge graph principles, the system explores graph visualization libraries to build stable mental models of complex software structures. Finally, this study proposes to evaluate the artifact through a comprehensive usability study with domain experts, while considering its support for users’ cognitive mapping.

Emotune: Exploring Context-Aware LLM Support for Driver Emotion Regulation

  • Laura Radetzky
  • Krishnakant Shedge
  • Krishnaben Patel
  • Tuğcan Önbaş
  • Gianluca Decaro
  • Lisa Neufeld
  • Deepak Jangir
  • Vanchha Chandrayan
  • Ignacio Alvarez

Driver emotions such as stress, frustration, and anxiety are associated with riskier behavior and reduced situational awareness, motivating in-vehicle systems that regulate affect in real time. However, emotion-only approaches capture how a driver feels, but not why, limiting appropriate support delivery. We present Emotune, a work-in-progress framework integrating emotional state assessment, driving-context awareness, and Large Language Model (LLM)-assisted intervention selection within the CARLA simulator. The framework uses a human-guided workflow, in which predefined interventions are selected by locally deployed LLM agents. As a methodological contribution, it enables studying how contextual information can inform emotion regulation in driving. We report a pilot study comparing a baseline emotion-aware agent with a context-aware agent that grounds interventions in driving situations. No statistically significant between-condition differences were found in the pilot study. Qualitative feedback instead highlighted contextual relevance, intervention timing, and perceived empathy as priorities for future investigation.

The Personality Behind the Wheel: Conversational Agent Design as a Strategic Asset for Automotive Brands

  • Esther Carolina Kähne
  • Ignacio Alvarez

As vehicles progress toward higher levels of autonomy, human–vehicle interaction will increasingly shift from driving-related tasks toward conversational engagement, highlighting the importance of conversational agent design. This paper presents a multi-method investigation of user-centered and brand-consistent visualization strategies for in-car conversational agents (ICAs), combining a quantitative survey based on personality and brand frameworks, an exploratory benchmarking analysis of existing automotive conversational agents, and an experimental study in a simulated driving environment examining responses to varying levels of visual abstraction and anthropomorphism. Preliminary results suggest that functional reliability and voice interaction quality form the primary acceptance baseline, while visual representation serves as a secondary and strategically differentiating layer. Rather than highly anthropomorphic or complex visualizations, adaptive concepts offering adjustable expressiveness, personalization, and modular abstraction emerge as a robust design direction for integrating ICAs into vehicle identity, user experience, and long-term human–machine relationships.

From Status to Reasoning: A Cross-Level Scoping Review of Trust Research at AutomotiveUI

  • Kasunika Guruge
  • Seul Chan Lee

Despite a decade of trust research at AutomotiveUI spanning the full SAE automation spectrum, a cross-level synthesis of the field’s own findings has not been explored. This PRISMA-guided scoping review examined 30 full papers screened from 338 candidates across ACM AutomotiveUI proceedings (2016–2025), coded across SAE level groups and two temporal eras. The analysis suggests three distinct psychological frames operating under the single label of trust, shifting from supervisory reliability at L1/2 through calibration at L3 to social delegation at L4/5. Across the reviewed studies, trust-calibrating HMI information followed a similar progression from system-status information toward system-reasoning information, a pattern this review characterized as the HOW–WHY information gradient. Seven of the nine L4/5 studies nonetheless placed participants in driver-seat configurations despite the passenger role of high automation, a recurring methodological pattern characterized here as a potential driver-seat paradox. Across multiple studies, subjective trust ratings and objective behavioral outcomes did not consistently align, suggesting an unresolved theoretical gap in understanding how trust is reflected in observable behaviour. Resolving this disconnect, establishing passenger-role designs at L4/5, and formalizing design knowledge at L1/2 are key directions for future trust research.

Supporting Car-Following Behaviors for Heterogeneous Drivers with Explicit Information of the Lead Vehicle

  • Xiaoyu Zhou
  • Dengbo He

Rear-end collisions are prevalent and are closely related to car-following (CF) behavior. In this study, we proposed three in-vehicle human-machine interfaces (HMIs) to provide progressively richer information about the lead vehicle (LV), including speed information (HMI-vel), time headway (THW) information on top of HMI-vel (HMI-THW), and coloured risk warnings based on THW thresholds on top of HMI- THW (HMI-alert). Cluster analysis was conducted to identify heterogeneous driver groups in a driving simulator study with 24 participants. Results showed that, in general, enhancing drivers’ perception of lead-vehicle states improved the safety margin during car-following segments without intensive braking, but certain HMIs impaired speed stability, with the effects varying across driver groups. Furthermore, the safety benefits of HMIs, reflected by reduced collision risk, differed across driver groups. These findings highlight the importance of considering driver heterogeneity and adaptive HMI designs to support safe car-following behaviors.

Buttons, Knobs and Switches: A Historical Exploration of Material and Type of Car Interior Interaction Points

  • Jesse Goddard
  • Rafael Gomez
  • Shayne Beaver
  • Robbie Napper

Exploring historical design trends helps reveal what shapes design evolution and may provide insight into future direction. This work-in-progress presents initial findings from a larger study spanning a 60-year period and explores patterns regarding the material use and type of interaction points within the car interior. Interior images from 57 Wheels “Car of the Year” winners, were collected, objectively coded, then analysed by their visual patterns. Preliminary findings and observations indicate a cyclic use of metal on some panels, the evolution and reduction of novel interaction points across the dashboard and center console, and the objective matrix provides opportunity to visualise further patterns. These preliminary findings contribute to the community by providing an understanding of past trends by tracking their propagation, teasing out meaning and decisions across different automotive market sectors, and to hint at interaction features that have persisted, offering relevance for future vehicle interiors.

Comparing Interface Modalities for Autonomous Vehicles among Older Adults in Sweden and Japan

  • Nihan Karatas
  • Neziha Akalin
  • Tamon Miyake
  • Sofi Fristedt
  • Maria Riveiro

Safe mobility is important for older adults, yet age-related declines may lead many older adults across cultural contexts to reduce or stop driving. Autonomous vehicles (AVs) could extend older adults’ mobility; however, this potential can only be realized if this technology is designed in ways that older adults prefer, accept, and find usable. This paper explores how interface modalities influence older adults’ perceptions of AVs in two cultural contexts: Sweden and Japan. We conducted a video-based online study with 44 older adults with driving licenses (22 from Sweden, 22 from Japan) comparing four passenger interface conditions across two scenarios with different visibility conditions: no interface, text-based, voice-based, and an embodied robot interface that communicates information about an AV’s actions. Our results indicate that providing an interface significantly improves older adults’ acceptance and trust relative to no-interface, with voice-based explanations yielding the highest mean acceptance in both countries. However, differences emerged: Japanese participants reported higher trust in the robot interface and more often selected a child-like voice, whereas Swedish participants more often selected adult voices. These findings suggest that tailoring AV human–machine interfaces to older users’ cultural expectations and communication preferences can enhance their comfort and adoption.

How to steer automated transport applications toward societal and traveler benefits: Fast Automated and Smart mobility impact Tool (FAST)

  • Gerbera Vledder
  • Nicole van Nes

Automated mobility solutions are rapidly advancing globally, offering potential benefits in safety, sustainability, efficiency, and inclusivity. However, these benefits are not guaranteed and could decrease if improperly managed. This paper introduces the Fast Automated and Smart mobility impact Tool (FAST), a method to assess and visualize automated mobility’s impact on travelers and society. Developed through an iterative design process involving literature review, tool design, and expert validation, FAST enables rapid initial assessments to stimulate discussion and inform decision-making. Preliminary validation shows potential but highlights the need for objective clarification, impact indicator refinement, and improved user group distinctions. Future work includes additional validation, framework elaboration, and interactive tool development to better support policy makers, researchers, and designers in evaluating automated mobility options. FAST can empower UI researchers to initiate dialogue with policy makers and industry, steering toward meaningful human-machine interactions, improving travel behavior, and facilitating acceptance of desired automated mobility futures.

Vehicle Kinematics as Implicit Cues: Comparing Cyclist-AV and Cyclist-HDV Crossing-Path Interactions Using Naturalistic Trajectory Data

  • Jingyu Li
  • Yue Yang
  • Natasha Merat
  • Yee Mun Lee

With the development of automated vehicle technologies, automated vehicles (AVs), human-driven vehicles (HDVs), and vulnerable road users (VRUs) are expected to coexist in mixed traffic for the foreseeable future. Amongst VRUs, cyclists face particularly high safety risks, making it important to understand how AVs should interact with them. HDV behaviour can serve as a useful benchmark, providing a reference point against which AV interactions can be evaluated and refined. However, it is currently not yet well understood whether AVs and HDVs exhibit different kinematic behaviours and interaction outcomes when interacting with cyclists. This study uses naturalistic trajectory data from the Waymo Motion Dataset to compare cyclist-AV and cyclist-HDV crossing-path interactions. The preliminary results indicate that vehicle kinematics may serve as important implicit cues. This work offers potential guidance for future research on understanding the role of vehicle kinematics in shaping safe and interpretable cyclist-AV interactions.

Situation-Aware Risk Assessment for Intersection Driving for Heavy Vehicles

  • Joe Steinhauer
  • Andreas Abser
  • Yacine Atif
  • Alicia Bernsland
  • Mikael Lebram
  • Paul Hemeren

Navigating unregulated intersections with a heavy vehicle is a challenging task harboring significant risks for the vehicle itself and other traffic participants. In this study we introduce a dynamic, evidence-based risk assessment algorithm predicting increased general risk at upcoming intersections based on environmental cues. We qualitatively evaluated two HMI configurations—a standard dashboard versus an adaptive Head-Up Display (HUD)—with professional drivers in a driving simulator. Drivers perceived the predictive risk indicator as highly useful, preferring the HUD layout. Despite physical simulator constraints, the results strongly support the utility of predictive general risk assessment. Future work will integrate real-time driver monitoring of eyes-off-road (EOR) metrics to dynamically adjust risk indicators based on driver attentiveness.

Beyond Driving Performance: Understanding Driving Experiences and Assistance Needs of Drivers with Parkinson’s Disease

  • Anna Preiwisch
  • Andreas Riener

Parkinson’s disease (PD) can impair abilities essential for safe and independent driving. However, little is known about how individuals with PD experience driving and perceive current driver assistance systems. At the same time, advances in driver assistance technologies may offer new opportunities to support mobility, independence, and continued participation in road traffic. To investigate these experiences and perceptions, we conducted an online survey with N = 52 individuals diagnosed with PD, followed by N = 9 semi-structured interviews exploring driving experiences, changes in driving ability, and attitudes toward assistance technologies. Our findings show that driving remains important for independence and quality of life, with many participants adapting their driving behavior rather than ceasing driving altogether. While driver assistance systems were generally perceived positively, participants emphasized the need for solutions that accommodate the diverse and evolving symptoms of PD. Based on these findings, we discuss opportunities and identify research directions for the design of PD-aware driver assistance technologies.

Modelling Subjectivity through Cognition: Toward Human-Fidelity Driver Digital Twins

  • Mohamed Amine Karoui
  • Adam Birdsall
  • Srivardhini Veeraragavan
  • Yannick Naudet

Digital Twins in the automotive domain have been developed to reproduce vehicle behaviour and optimise performance, yet the subjective driving experience remains largely unaddressed. Existing Driver Digital Twins reproduce observable control actions but do not represent the internal processes through which subjective experience arises, limiting their ability to account for why the same physical situation can be experienced differently by different drivers. This paper argues that subjectivity is a cognitive phenomenon and that a model of human cognition, specifically cognitive architectures, can provide a relevant modelling layer for a Human Driver Digital Twin. Four dimensions of driver subjectivity are discussed and mapped to cognitive architecture mechanisms. This represents a step toward Driver Digital Twins with greater human fidelity, though much remains to be specified before such systems can be realised. Grounding driver models in cognition opens directions for designing systems that are responsive to the human dimension of driving.

A Staged Workflow for Driver Glance and Hand-State Annotation

  • Zhixiong Wang
  • Zeyun Du
  • Yuwen Chen
  • Dengbo He

Naturalistic driving video captures how drivers supervise under real road conditions, but converting long, multi-camera in-cabin footage into behavioral features still relies on manual coding, which is costly and hard to scale. We present a human-in-the-loop workflow that converts raw in-cabin video into two reviewable supervisory features: area-of-interest (AOI) gaze labels and hand-on-wheel state. Instead of a single end-to-end model, the workflow keeps region selection, gaze labeling, participant-specific calibration, temporal stabilization, and window-level metric extraction as distinct, observable stages, so an error can be localized. Specifically, the gaze module pairs Sample and Computation Redistribution for Efficient Face Detection (SCRFD) face detection with a YOLOv8-cls classifier, while the hand module uses GroundingDINO with a temporal state stabilization strategy. The workflow was validated in a naturalistic driving study with millions of video frames from 15 drivers. The source code of the workflow has been released at https://github.com/zdu881/autodri.

When the Prompt Speaks Louder than the Person: Output Anchoring in Personality-Informed LLM Emotional Support for Drivers

  • Max Mittelstädt
  • Ece Sutanrikulu
  • Lumbardh Ljatifi
  • Julia Geltl
  • Berfin Berg
  • Ann-Marie Atzkern
  • Anusha Kanagarasa
  • Vanchha Chandrayan
  • Ignacio Alvarez

This Work-in-Progress examines whether personality-informed prompting changes perceived LLM emotional support in driving scenarios designed to elicit stress. A condition-order-balanced, within-subject CARLA simulator study (n = 14) compared a baseline with a Driver Personality Profile (DPP) condition; a supplementary online video pilot (n = 12) examined response perception without driving control or live-system latency. No statistically detectable condition differences emerged for usefulness, ease of use, privacy concerns, or social/emotional presence, and only 7 of 14 simulator participants identified the DPP condition correctly. A post-hoc lexical audit showed that both conditions frequently reused generic supportive scaffolding. We discuss output anchoring as one tentative interpretation, not an established phenomenon: the evidence cannot distinguish constraint-dominated generation from a weak personalization manipulation or limitations of the 7B model. The findings motivate stronger, independently validated personalization manipulations and privacy-aware in-vehicle support.

Exploring Veo 3’s Capabilities for Generating Urban Traffic Scenes in 76 Cities Worldwide

  • Md Shadab Alam
  • Zi Wang
  • Linghan Zhang
  • Pavlo Bazilinskyy

This study explores the potential of Google Veo 3, a generative video model, to synthesise 8-second dashcam-style urban traffic scenes based solely on text prompts in 76 cities across six continents. YOLOv11x was used to count road users, traffic lights, and stop signs, revealing variations across cities: Karachi had the most objects detected (79), while Muscat had only four cars. Audio analysis using dBFS showed that Montevideo was the loudest, while Copenhagen was the quietest. Through a qualitative visual analysis, the authors assessed and confirmed the perceived authenticity of most traffic scenes and highlighted AI errors, including the inability to handle non-English languages in these videos. Moreover, we compared 10 synthetic videos of New York City and Kampala, each, and verified that Veo 3 is consistent. To summarise, Veo 3 is capable of synthesising authentic, logical traffic scenes worldwide; nevertheless, it still poses non-negligible errors.

So Pedestrian: Designing AV Detection Displays Around Human Perception

  • Grace A Douglas
  • Linda Ng Boyle

In-vehicle pedestrian detection displays show what a vehicle senses, but a sensor detects more than a display can usefully present. We argue that what a display surfaces should be prioritized by human monitoring: confirm the pedestrians an occupant reliably detects, and flag those they miss. In an SAE Level 4 driving simulator, participants monitored an automated drive and reported pedestrians under intermittent visual-search load. Across 488 encounters from 27 participants, moving pedestrians were detected 90–98% and a stationary, occluded pedestrian 44%, despite passing within 7 m. Detection tracked visual salience, not proximity. Projecting position into the gaze record shows the miss is split: in about half, gaze reached the pedestrian and went unreported; in the rest, gaze never arrived. Adding dashboard detail raised trust without raising workload but did not recover the missed pedestrian, implying the safety cue belongs in the environment, not on a dashboard panel.

Beyond the Fear of the unknown: Designing a Transparency-Driven Interface for Calibrated Trust in Autonomous Vehicles

  • Suzi Choi
  • Jinhyeong Kim
  • Sehee Lee
  • Insoo Park
  • Jihyeok Bang
  • Hyungjin Choi

As autonomous-driving systems take on increasing control authority, drivers are repositioned as human supervisors who must monitor decisions they did not make. Yet, today’s in-vehicle interfaces expose only the system’s final actions, leaving its underlying perception and reasoning invisible — a structural information asymmetry that manifests as a chronic fear of the unknown and undermines calibrated trust. Drawing on a formative study with 18 experienced ADAS users, we show that drivers’ trust is shaped more strongly by why and what-next explanations than by mere object recognition, and that the largest gap between current and desired information lies in intent, reasoning, confidence, and limits. Building on these findings, we derive three design principles that align the autonomous-driving pipeline with the driver’s reasoning order, and instantiate them in the Transparent ADAS Interface — a two-area design that communicates the vehicle’s behavior and intent alongside what the system perceives and how confidently it does so.

From Physiology to Car-Following: Analysis and Prediction Across Driver Fatigue States

  • Yang Liu
  • Feiqi Gu
  • Dengbo He

Although extensive research has been conducted on driver fatigue detection, few studies have explored how fatigue affects drivers’ car-following behaviors and, in turn, how to detect fatigue based on car-following features. In an on-road experiment, we collected multimodal physiological data and eye-tracking data from 5 long-haul truck drivers, along with vehicle motion and surrounding traffic data. Drivers’ fatigue states were labeled based on the percentage of eyelid closure over the pupil (PERCLOS). Comparative analyses of car-following behavioral parameters and physiological indicators under different fatigue states were performed. Furthermore, we explored the feasibility of estimating drivers’ fatigue levels using car-following behavioral parameters and compared its performance with models based on physiological features. The results show that the models based on car-following features showed better performance than models based on physiological indicators in this preliminary endeavor. These findings provide theoretical evidence for the feasibility of detecting surrounding human-driven vehicles’ fatigue states based on their driving characteristics using lightweight, interpretable, and practically deployable models.

The Role of Conversational Agents for Long-haul Truck Drivers: An Exploratory On-road Study

  • Johanna Vännström
  • Andreas Absér
  • Azra Habibovic
  • Jacob Weilandt
  • Stefan Mattsson

While conversational AI agents (CAs) have the potential to support drivers through hands-free and eyes-free interaction, their role in long-haul trucking remains unexplored. This paper investigates how long-haul truck drivers perceive CAs and identifies design considerations for their successful deployment. We conducted ride-along observations and semi-structured interviews with five long-haul truck drivers during regular driving operations. The results show that drivers today regulate verbal communication according to driving demands and expect communication partners to adapt to changes in workload and attention. Participants were most receptive to CAs supporting driving-related tasks, including traffic information, rerouting and route planning. Trust, perceived complexity, and discomfort with conversational interaction emerged as key barriers to adoption. We conclude that CAs may be best suited to supporting strategic and selected tactical tasks, while being less appropriate for operational tasks. Effective CA design must adapt to context and workload, support interruptions, and provide transparent and trustworthy support.

Beyond User-Reported Experience: Convergent Evidence for Visual Interface Quality Assessment in Teleoperation

  • Shirin Rafiei
  • Kjell Brunnström
  • Bo Schenkman
  • Gabriele Pifferi
  • Anders Djupsjöbacka
  • Börje Andrén

Visual interface design strongly affects operator performance in teleoperated remote inspection, yet evaluations have typically relied on user-reported ratings alone. We report a within-subjects laboratory study (n = 24) comparing five visual interface configurations for a teleoperated mobile platform, including a static depth-cue overlay tested in both single-view (first-person view; FPV) and dual-view (FPV plus third-person view; TPV) configurations. Helpfulness, on-FPV gaze dwell, and task performance all ranked the TPV-only condition below each FPV-based condition, providing convergent behavioural evidence for the user-reported condition ordering. Within FPV-based conditions, the overlay systematically redirected gaze into its target region, holding across the large majority of participants in both viewing configurations, yet user-reported helpfulness showed no corresponding augmentation effect. This dissociation between behavioural and self-report measures was echoed in modest but consistent trial-level correlations between helpfulness and the behavioural measures. These findings support combining gaze allocation and task performance with user-reported ratings in teleoperation interface evaluations.

Experts’ and Community Insights on Measuring Comfort and Perceived Safety in Automated Driving: Synthesis of a Participatory Workshop

  • Chen Peng
  • Pavlo Bazilinskyy
  • Yueteng Yu
  • Marieke Martens
  • Riender Happee
  • Kumar Akash
  • Natasha Merat

Accurately measuring comfort and perceived safety in automated vehicles (AVs) is critical for understanding user experience, accommodating various needs, and eventually contributing to the public acceptance of AVs. However, methodological practices vary largely across the field. To address this gap, we organised a workshop at AutomotiveUI 2025, where three expert talks covered subjective measurements, objective and physiological measures, and AI-driven models, followed by two structured group discussion sessions on current practices and future methodologies. This work-in-progress synthesises key insights from both the expert talks and community discussions. Critical themes include, for example, the need for context-specific, deliberate selection of subjective measures; the promise and practical limitations of physiological signals; the ground truth challenge that complicates subjective-objective combination; and the emerging role of artificial intelligence (AI) for real-time inference and multimodal combination. We offer these insights to provide the community with a common methodological landscape and to promote more robust practices.

Motions Speak Louder Than Words: Designing Human-like AV Speed Profiles at Crosswalks with a Bayesian Optimisation–Driven Adaptive Experiment

  • Yuwei Wang
  • Gustav Markkula
  • Yee Mun Lee

Autonomous vehicles (AVs) must communicate intent to pedestrians in mixed traffic to ensure safe interaction, and vehicle deceleration motion is a promising implicit communication channel. Designing acceptable AV deceleration remains difficult because it is continuous with interdependent kinematics, making fixed‑design experiments inefficient. We therefore parameterised deceleration using a minimum‑jerk model (MJM), which generates smooth speed profiles from tuneable parameters. We will conduct an adaptive experiment in an immersive pedestrian simulator, where Bayesian optimisation sequentially proposes AV deceleration profiles expected to receive higher pedestrian ratings for safety and efficiency, based on previous ratings. Preliminary results from fitting MJM to 62 naturalistic human profiles indicate that the MJM reproduces the overall human profile shape (median RMSE = 0.88 m/s) with only 2 parameters (i.e., stopping distance, duration), supporting its use as a profile generator for the experiment. This work can contribute a human-in-the-loop framework for designing AV motion as an implicit interface.

Method to integrate Automotive User Interface Prototyping with Mixed Reality Simulation

  • Thirumanikandan Subramanian
  • Wolfram Remlinger

This paper presents a method to integrate virtual car interiors with interactive User Interfaces (UIs) for holistic simulation in a mixed reality (MR) environment, coupled with an adjustable seating buck. For user-centric development of automated vehicles, early-stage feedback on interiors, including Human-Machine Interfaces (HMIs), is highly essential. Methods to simulate automotive interfaces integrating ergonomics and mixed reality techniques that include users in early phase testing are still not explored enough. The proposed method is implemented in Unreal Engine (UE). It showcases the workflow for integrating User Interface (UI) prototypes developed on external platforms like ProtoPie and Figma into the UE platform, thus not only representing the UI visually but also integrating the UI prototype’s interaction logic with the simulation environment bi-directionally. This UI prototype simulation is coupled with the adjustable seating buck to evaluate ergonomic aspects, and integrated with a mixed reality workflow to represent both the user’s body and the desired 3D model variant of the interior. A Pilot study was performed to validate the proof of concept (POC).

Your Stomach Knows Best? Using Electrogastrography to Assess Motion-Sickness-Related Discomfort in Comfort-Oriented Automated Vehicle Interfaces

  • Timotej Gruden
  • Grega Jakus
  • Jaka Sodnik
  • Kristina Stojmenova Pečečnik

In this paper, we present a novel approach of assessment of user interfaces, designed to positively affect passenger comfort, using electrogastrography (EGG). EGG is a method that records electrical activity of the stomach, and has been shown to reliably assess motion sickness, which is one of the main contributors to physical discomfort in AVs. A user study with 26 (22 complete data sets for analysis) participants was conducted in a driving simulator, assessing three types of auditory-tactile user interfaces (UI) (baseline, abstract, representational) for highly automated driving using EGG features such as dominant fre-quency, tachygastria, and crest factor of spectral density. The results indicate that the percentage of power spectrum density in the tachygastric range increased when using an abstract UI during events requiring lateral AV maneuvers. These findings suggest that EGG can serve as an objective method for evaluating passenger-centric interfaces in future vehicles.

From Papers to Production: Opportunities and Challenges in Academic Automotive HMI Research Translation – An Expert Interview

  • Wei-Hsiang Lo
  • Regan Plank
  • James Rampton
  • Derek Fraser
  • Manhua Wang

AI-based assistance is expanding in-vehicle functions and increasing how often drivers use human-machine interfaces (HMIs) in everyday driving. This growing role makes research on safe and effective interface design increasingly important to automotive development. Academic research has produced a body of work relevant to this need. However, automotive-specific research has documented continuing challenges in communicating and incorporating this knowledge into vehicle-development practice. To examine this research-practice gap from practitioners’ perspectives, this exploratory study conducted semi-structured interviews with 12 experts from original equipment manufacturers (OEMs) and related industry organizations. The thematic analysis identified five themes concerning HMI value, decision-ready evidence, collaboration structure, internal governance, and layered evidence use. These themes led to three practical recommendations: make findings actionable, create outputs beyond academic papers, and engage OEM partners early. Overall, the findings aim to strengthen collaboration between academic researchers and industry practitioners and support future automotive HMI development.

Using Physiological Signals to Diagnose Driver Situation Awareness Deficits for Takeover Support in Automated Driving

  • Wei-Hsiang Lo
  • Jincheng Ye
  • Manhua Wang

Takeover support requires identifying the situation awareness (SA) deficit affecting a driver’s response. A single SA measure cannot identify the deficit or support need. This study therefore defines support-relevant SA across two layers. The traffic-event layer identifies support timing and location through temporal (materialized and unmaterialized hazards) and spatial (forward path and adjacent lane) dimensions. The information-processing layer uses Quantitative Analysis of Situation Awareness (QASA) to separate actual SA (ASA; situation knowledge), perceived SA (PSA; confidence), and response bias (response criterion). Their intersection yields 12 support-relevant targets. Using physiological signals from 66 participants, the study applied the Weighted Importance Score and Frequency Count (WISFC) framework across six model families to compare retrospective window-level feature rankings. ASA and response bias rankings showed preliminary variation, whereas PSA shared pupil and gaze features across dimensions. These patterns suggest which targets may be physiologically distinguishable or require contextual evidence for takeover support.

“Do as I say”: Analysis of In-vehicle Assistant Command Pattern Differences between Germany and Mexico

  • Ignacio Alvarez
  • Juan Manuel G Gonzalez
  • Alan Daniel Salas Parada
  • Harold Tass Oliver

In-vehicle assistants (IVAs) are moving from fixed command grammars toward large language model (LLM) driven conversational agents, where the quality of the system’s response depends heavily on how the driver phrases the request. Yet we know little about how drivers actually formulate spoken commands, and almost nothing about how this varies across cultures and languages. We present the design and motivation of PromptDrive, a web-based, remote, unattended driving-simulator platform that elicits spoken command utterances under three priming styles (Direct, Goal-based, and Contextual) delivered through a simulated head-up display. We ran a cross-cultural, multilingual pilot study with university students in Germany and Mexico, assembling a trilingual (German, Spanish, English) corpus of command utterances for two vehicle functions, navigation and climate control. In this work we frame the cross-cultural IVAs prompting problem, situate it in prior work on cross-cultural HCI, and prompting, and motivate why command-phrasing patterns may differ systematically between a German and a Mexican driver population. We report preliminary observations from 30 participants and 383 utterances: priming style shifts how drivers phrase requests, with Direct cues yielding the shortest commands and Goal-based cues the most specific, while retrospective workload did not differ across styles and drivers preferred the Direct framing. Because the achieved sample fell short of the planned size and the cells are unbalanced, these results are exploratory; the paper’s primary contributions are the conceptual framing, the elicitation protocol, and evidence that the platform supports unattended multilingual collection at a distance.

Evaluating Multimodal Explainable AI in Ambiguous Driving Scenarios: Effects on User Trust and Satisfaction

  • Ignacio Alvarez
  • Tobias Seidl

This paper investigates how different Explainable Artificial Intelligence (XAI) modality combinations affect users in fully automated vehicles across different types of ambiguous driving scenarios (ADS). In an online study (N = 123), three explanation modality combinations were compared: visual-textual (VT), visual-auditory (VA), and visual-textual-auditory (VTA). VT resulted in significantly lower situational trust and significantly higher cognitive load than VA and VTA. Explanation satisfaction increased significantly from VT to VA and was highest for VTA. While baseline levels of trust, satisfaction, and cognitive load differed between ADS categories, no significant modality–scenario interaction was found, indicating that modality effects generalize across forms of ambiguity. Based on these results, five design guidelines for XAI in fully automated vehicles were derived. Overall, multimodal explanations appear beneficial, particularly during initial use, but should adapt to user needs and context.

EchoDrive: Gamification of Perceptual Guidance via Spatial Audio in AV Driving Simulation

  • Julia Podlipensky
  • Vanessa Scherer
  • Monika Szuban
  • Ignacio Alvarez

As vehicles become increasingly automated, the driver’s role is shifting from active controller to passive supervisor. Automation reduces manual effort, but it also introduces the risk of disengagement and decreased situational awareness. This paper presents EchoDrive, a gamified in-cabin system designed to support situational awareness (SA) in vehicle occupants during automated driving through spatialized audio cues and gesture-based responses. The system allows drivers to initiate sonar-like scans and point toward the audio cues responses of the detected traffic participants, fostering periodic perceptual engagement. A within-subjects simulation compared EchoDrive to a mobile game baseline. Results showed that, compared to a visually demanding smartphone game baseline, EchoDrive increased subjective driver SA, reduced reported cognitive workload, and improved takeover readiness, while being positively received by participants. This work highlights the potential of lightweight multi-sensory interaction to support driver presence in automated vehicle contexts, though the asymmetric comparison limits attribution to specific design elements.

Neither Driver nor Machine: An Autoethnography of Riding Deployed Robotaxis in Shenzhen

  • Xinyan Yu
  • Tram Thi Minh Tran

Robotaxis are beginning to move beyond restricted pilot programmes and enter everyday traffic in selected cities. Yet much of what we know about interacting with autonomous vehicles (AVs) has been established in simulators and labs, leaving the lived experience of riding a deployed robotaxi underexplored. In this work, we conducted an autoethnographic study of five robotaxi rides across two platforms in Shenzhen. Drawing on our first-hand experience as passengers as well as our expertise in AV research, we surface three tensions: a habitual urge to monitor the road that persists beyond prevailing trust-vigilance accounts; an uncanny unease as the vehicle negotiates traffic too convincingly like a human driver; and the friction of pick-up and drop-off, where the passenger becomes a pedestrian the system no longer attends to. In response to each tension, we offer design considerations that extend current interaction design paradigms to capture the nuances of robotaxis as they operate in real-world settings.

Evaluating Multimodal Touchscreen Interfaces for V2V Overtaking Requests in Virtual Reality

  • Rodrigo Rodrigues
  • Jorge C. S. Cardoso

In future driving, manual drivers will interact with Autonomous Vehicles (AVs) through Vehicle to Vehicle (V2V) communication. This study evaluates the human-machine interaction trade-offs of interface modality stacking for center-stack touchscreens during a cooperative overtaking task. Using a Virtual Reality driving simulator with 26 participants performing a visual secondary distraction task, we compared three configurations: Visual (V), Visual+Haptic (VH), and Visual+Auditory+Haptic (VAH) across normal and time-sensitive requests. Results show that the VAH setup improved overall driver response times, and enhanced request-type classification accuracy for time-sensitive requests. However, an interaction effect revealed that modality stacking sequentially escalated perceived pressure and subjective workload (temporal demand and frustration) specifically during time-sensitive requests. A marginal trend indicated increased system intrusiveness as sensory layers accumulated. These suggest a design trade-off for cooperative driving Human-Machine Interfaces (HMIs): while multi-sensory density dramatically recovers tactical accuracy, it carries an immediate psychological cost that designers must try to mitigate.

Second Pair of Eyes: Evaluation of a Helmet-Integrated Multimodal HMI for Proactive Motorcycle Safety

  • Thomas van Heuvelen
  • Pavlo Bazilinskyy

Motorcyclists are highly vulnerable in complex traffic, where hazards are often detected too late for a timely response. We evaluated MOTEX, a helmet-integrated HMI that provides proactive directional cues through peripheral visual, auditory, and multimodal feedback. In a within-subject simulator study, 14 participants completed 16 scenarios based on common motorcycle crash typologies. The feedback mode did not significantly affect the reaction time or the minimum time-to-collision, although the visual and multimodal conditions showed numerically faster responses and greater safety margins than the audio and control conditions. Participants reported low cognitive workload, moderate trust, and generally positive evaluations of cue clarity. Perceived benefits of situation awareness were mixed, with most of participants reporting a neutral effect. These findings suggest that MOTEX may function less as a direct determinant of behavioural response and more as a supportive “second pair of eyes’’ for spatial confirmation.

Learning a Simple Directional eHMI: A VR Study of AV-Pedestrian Interaction

  • Christian Janssen
  • Md Shadab Alam
  • Fei Dou
  • Pavlo Bazilinskyy
  • Linghan Zhang

External Human-Machine Interfaces (eHMIs) for automated vehicles must remain quickly interpretable if they are to scale to realistic traffic. This study examines a deliberately simple directional light-based windshield eHMI as a first step toward that goal. The eHMI uses a minimal light strip whose highlighted segment shifts based on the pedestrian’s relative position, aiming to convey yielding intent without text or complex visual elements. In a virtual-reality study with 30 participants, pedestrians encountered an automated vehicle with and without the eHMI; half received a brief onboarding video, while the others learnt through repeated exposure. Results suggest that the eHMI supported earlier crossing initiation and increased perceived safety and trust. Onboarding produced immediate benefits, whereas participants without onboarding showed gradual improvements over repeated encounters. These findings indicate that the signal is learnable in a controlled dyadic setting and motivate future VR studies of multi-pedestrian interaction, social influence, and traffic complexity.

Path Weavers: Making Road Infrastructure Legible for an Autonomous Future Through Gamified Immersion in a CAVE Installation

  • Joshua von Beckerath
  • Max Mittelstädt
  • Lukas Valentin Kolb
  • Olivia Dölling
  • Gauri Sopan Kakad
  • Jakob Peintner
  • Andreas Riener

A city’s traffic runs on planning decisions almost nobody sees, and autonomous vehicles widen that gap: they read the road network and route through it, while the people sharing the street understand less and less of how it works. Path Weavers is a concept for closing that gap through play. It turns a CAVE into a living city where two or more players take opposing roles. One side builds the road network, the other disrupts it with urban events, and the vehicles navigate whatever infrastructure exists. The room itself does the explaining: traffic state shows through color, sound and floor feedback rather than menus or screens. Beyond a short briefing, players get no instructions, so the central problem is legibility, which we address with a layered Explainable UI. This paper presents the concept, the decisions that shaped it, and the open questions we bring to the AutoUI community.

CTA-STGT: A Cortical Topology-Aware Spatiotemporal Graph Transformer for EEG-Based eVTOL Pilot Cognitive Workload Estimation

  • Chenglin Liu
  • Wenjun Zhang
  • Zhijie Yi
  • Jiyao Wang
  • Xiang Chang
  • Dengbo He

As urban air mobility (UAM) advances toward operational deployment, electric vertical takeoff and landing (eVTOL) pilots may face heightened cognitive demands from dense low-altitude traffic, strict energy constraints, and safety-critical flight phases with complex control-mode transitions. Real-time pilot state monitoring is therefore essential for safe operations. Prior electroencephalography (EEG)-based workload-estimation models for pilots predominantly focus on temporal dynamics, while insufficiently modeling inter-channel dependencies, which are crucial for effective spatial aggregation across EEG electrodes. In this study, we propose the Cortical Topology-Aware Spatiotemporal Graph Transformer (CTA-STGT), which explicitly encodes structured inter-channel relationships via a topology-aware graph convolutional network constrained by a cortical-topology-derived adjacency matrix. Temporal patch embeddings and spatial graph embeddings are projected into a unified latent space and then jointly fused by a Transformer encoder to capture spatiotemporal dependencies. Evaluated on EEG data from a 6-degree-of-freedom eVTOL simulator experiment with three workload levels based on NASA Task Load Index (NASA-TLX) scores, CTA-STGT achieved an accuracy of 0.89 and an F1-score of 0.89, outperforming the baseline models. These results provide a technical basis for adaptive workload-mitigation support in high-workload eVTOL scenarios.

Review Method Considering Attitude Change that Affects Correction of Overestimation of Older Drivers

  • Shuto Inouchi
  • Hiroshi Yoshitake
  • Motoki Shino

To effectively correct older drivers’ self-estimation, we proposed a review method that considers the attitude change associated with the correction of their overestimation. First, reanalyzing previous data, we hypothesized that the attitude change in optimistic comparison with same-age drivers is associated with the degree of overestimation correction. To verify this hypothesis, we conducted an attitude survey before and after a self-estimation correction education. The results supported this hypothesis. Based on these findings, to reduce their optimistic attitude toward their own driving compared to same-age drivers, we proposed a review method that presents and compares the driving evaluations of other same-age drivers alongside the participant’s own driving evaluation in a driving simulator. To evaluate the proposed method’s feasibility, we conducted a preliminary experiment with three older drivers, which indicated its potential to effectively reduce optimistic comparative attitude compared to same-age drivers and correct overestimation.

Relaxation During Automated Driving: An Exploratory Study of Subjective Assessments, Psychophysiological Responses, and Driving Metrics

  • Jutta Hild
  • Oliver Riethmüller
  • Timo Sandrock
  • David Jonathan Lerch
  • Jonas Birkle
  • Frederik Diederichs
  • Verena Wagner-Hartl

Conditionally automated driving offers engagement in non-driving-related activities such as relaxation. The present driving simulator study (N = 12) compares three relaxation methods, Closing the Eyes, Sounds of Nature, and Diaphragmatic Breathing, considering their impact on driving performance, physiology, and subjective experience. The best results were achieved with Sounds of Nature in the majority of the different evaluation categories.

Exploring the Design Space of Adaptive Explanations in Automated Vehicles

  • Philipp Michael Markus Peter Asteriou
  • Ambika Shahu
  • Philipp Wintersberger

Explanations in automated vehicles have been proposed to support users’ understanding, trust, and acceptance of automated driving behavior. However, many explanation interfaces remain static interventions, even though users’ information needs may vary depending on driving context, familiarity, perceived criticality, and preference. This work presents a simulator platform for prototyping adaptive in-vehicle explanations in automated driving. The platform combines a Unity-based driving environment, a motion-based, VR-enabled setup, scripted traffic incidents, an in-vehicle explanation interface, and a feedback loop to adapt explanations. The system uses a large language model-based explanation pipeline that receives scenario information and user feedback to determine whether an explanation should be presented, how detailed it should be, and how it should be delivered. We describe the platform, outline the design space it enables, and reflect on how such systems can support AutomotiveUI research on adaptive explanations, explanation suppression, user control, and human-AI interaction in automated vehicles.

Representing Users: Worthwhile or Just Molièreing it? Exploring Accessibility Challenges in Automated Buses

  • Wanjun Chu
  • Fredrik Henriksson
  • Simon Schütte
  • Tibella Toma
  • Maja Elin Linnéa Willén
  • Youssra Zouhair

This paper explores how accessibility challenges for older adults in automated buses can be understood through different forms of user representation. Two explorative studies were conducted in an actual stationary automated bus: a user enactment study with three older adults with mobility, vision, and hearing impairments, and an empathy simulation study with six non-target participants using a kit to simulate age-related capability loss. Findings from both studies highlight the importance of multimodal communication, interior design support, and human assistance for older passengers. Beyond these design insights, the paper contributes a methodological reflection on how user enactment and empathy simulation produce different forms of accessibility-related user knowledge. Empathy simulation enables safer exploration of critical interaction scenarios and challenges existing design assumptions, while user enactment with target users grounded such insights in lived experience, situated strategies, and actual capability variation.

SESSION: Workshops

Love In Traffic: Physical and Digital Design Against Consensual Sexual Activity Inside Public and Shared Automated Vehicles

  • Alexandros Rouchitsas
  • Ignacio Alvarez
  • Soyeon Kim
  • Chen Peng
  • Pavlo Bazilinskyy

Research on sexual behavior and transport has either focused on fear of sexual harassment and perceived safety inside public transport or on consensual sexual activity inside private transport framed as distracted driving. Meanwhile, evidence from adult content platforms suggests that consensual sexual activity inside public transport is trending. This is particularly concerning in relation to public and shared automated vehicles (AVs), where enclosure, shared use, and the absence of an authority figure can warp perceptions of accountability and intervention potential, with important consequences for passenger comfort and perceived safety and for public acceptance of the technology. Our workshop aims to address this concern by approaching consensual sexual activity as a design stress test for how AVs are perceived and used as collective spaces. We aim to synthesize design principles, identify open research questions, and establish a research agenda for designing public and shared AVs as comfortable and respectful collective spaces.

2nd Workshop on Exploring the Potential of XAI and HMI to Alleviate Ethical, Legal, and Social Conflicts in Automated Vehicles: Applying HCXAI to Discover User Explainability Needs

  • Krishna Sahithi Karur
  • Andreas Riener
  • Philipp Wintersberger
  • Manhua Wang
  • Philipp Michael Markus Peter Asteriou
  • Seul Chan Lee

As automated vehicles (AVs) are increasingly deployed in real-world environments, users often do not understand what decisions their vehicles are making, or why. Explainable AI (XAI) offers a promising path toward transparency, yet most existing approaches remain algorithm-centric and inaccessible to end users. This workshop explores how Human-Centered XAI (HCXAI) and the Question-Driven Design framework can be used to systematically discover user explainability needs for AVs. Through scenario-based, participatory activities, participants will adopt different stakeholder perspectives and generate the questions they would want an AV to answer in ambiguous driving situations. Building on the prior workshop at AutomotiveUI 2025, this workshop aims to produce an initial taxonomy of AV-specific explanation needs grounded in real user questions, creating a shared resource that can guide future research, UI design, and evaluation of explainable automated driving systems.

From Roadways to Shared Spaces: Extending Vehicle eHMI Research to Public Mobile Robots

  • Suhwan Jung
  • Young Woo Kim
  • Xinyan Yu
  • Callum Parker
  • Byungju Kim
  • Joel Fredericks

Public Mobile Robots (PMRs), including last-mile delivery, street-cleaning, and guide robots, are increasingly being deployed in shared public spaces such as sidewalks, corridors, and building entrances, where they must communicate and coordinate with nearby pedestrians. Unlike automated vehicles, PMRs operate in close proximity to people, introducing new challenges for intent communication, trust, and socially acceptable interaction. While the AutoUI community has established extensive knowledge on external Human–Machine Interfaces (eHMIs) for automated vehicles, it remains unclear how these principles transfer to PMRs. This workshop aims to examine the applicability of vehicle-based eHMI concepts to PMRs by identifying transferable design principles, challenges requiring adaptation, and new research directions. Through invited talks, comparative discussions, and scenario-based group activities, participants will develop a shared research agenda, propose preliminary design considerations for PMR eHMIs, and strengthen collaboration between the AutoUI and Human–Robot Interaction communities.

Workshop on Redefining the Relationship Between Human Operator and Driver Monitoring System (DMS): From Passive Safety to Active Partnerships

  • Linda Ng Boyle
  • Alexandria M Noble
  • Natasha Merat
  • Christian P. Janssen
  • Vishnu Radhakrishnan
  • Alexander Eriksson
  • Amélie Reher
  • Martin Baumann

Driver monitoring systems are typically designed to detect driver states and as appropriate, issue corrective warning and/or take action (alert, takeover, etc.). Current warning strategies are designed by a rule-based deterministic model, given ease in certification and predictability, with little or no personalization and adaptation to a driver’s individualistic profile and preferences. However, long-term effectiveness of these systems, including wider adoption, depends not only on detection accuracy, but on whether drivers perceive the system to be useful, trustworthy, and supportive. In this workshop, we discuss the benefits of a value-in-use approach that provides context-sensitive interventions to account for driver, situational, and environmental variations. The term “value-in-use” refers to the concept that a system’s worth is determined by what it can deliver to the driver in a real-world setting. Drivers are more likely to accept and benefit from a driver monitoring system that is viewed as a partner in safe driving rather than an intrusive or punitive supervisor. This workshop will present a conceptual roadmap that addresses the questions, “Does the system create value for the driver for real world use” and “What relationships (or partnerships) should exist between humans and systems to provide value?” The workshop advocates moving beyond compliance-oriented warning logic towards a user-centered paradigm in which driver monitoring systems create value through adaptive, relational, and meaningful support, in use. Participants will be asked to provide use case scenarios based on a shared understanding of the possible partnerships that can evolve during a trip.

Shaping Future Propositions of Automated Mobility Interaction: Facilitating evaluation and improvement with the Fast Automated and Smart Mobility impact Tool

  • Gerbera Vledder
  • Rafael Gomez
  • Haoyu Dong
  • Nicole van Nes

Automated mobility is reshaping society, yet its development has been primarily OEM-driven, often prioritizing business over societal and individual gains. The goal of this workshop is to facilitate debate around automated mobility impact with the use of the Fast Automated and Smart mobility impact Tool (FAST), and to discuss the role of design-research in working towards smart mobility futures. FAST enables stakeholders to evaluate systems against individual and societal values. Participants will use FAST to brainstorm, assess, and refine automated mobility propositions (from demand-responsive transport to automated mobility scooters, or cars), balancing benefits against risks. The workshop familiarizes participants with the potential impact of automated mobility and provides them with a hands-on tool for discussions around the topic. Outcomes include evaluated use cases, actionable improvements, and recommendations for industry, policy, and the Human Factors and Design research community.

What Caused the Accident? Speculating Accessibility Challenges in Automated Buses for Older Adults

  • Wanjun Chu
  • Torbjörn Andersson
  • Fredrik Henriksson
  • Simon Schütte
  • Elena Jiménez Romanillos
  • Franziska Felicitas Babel

Automated buses are increasingly being deployed in public transport systems. In Linköping, Sweden, they have been in daily operation since 2020. However, their deployment has also raised critical accessibility and inclusive design challenges. There is growing concern regarding how automated buses can accommodate users with diverse mobility, sensory, and cognitive capabilities, especially older adults and people with impairments, throughout the entire user journey. In this workshop, we apply a speculative design approach to engage participants in investigating a fictive accident involving older adult passengers. We translate these speculative scenarios into design research questions addressing safety, accessibility, and inclusivity. Using the automated bus deployment in Linköping as the setting, the workshop aims to generate insights that bridge the gap between research and real-world deployment for a more accessible and inclusive autonomous public transport system.

Anthropomorphic and Intelligent Assistive Systems for Automated Vehicles

  • Neziha Akalin
  • Nihan Karatas
  • Sofia Thunberg
  • Alexey Vinel
  • Robert J Lowe

Semi-automated vehicles utilizing interactive interfaces represent a critical, emergent research field for enhancing road safety and user experience. This half-day workshop aims to advance the design and evaluation of anthropomorphic, intelligent in-car assistants to foster trust and mitigate risks like driver distraction or over-trust. Through paper presentations and interactive discussions, participants will explore agent morphology, spanning voice-only systems, screen-based interfaces, and physical robotic agents, and investigate how these agents can effectively communicate vehicle intentions and driving context. Additionally, the workshop will address the impact of these in-car assistants on driver workload and control takeovers, while establishing robust evaluation metrics, ethical guidelines, and global standardization frameworks. By bridging robotics, vehicular communication, human-machine interaction and automatic control, this workshop seeks to synthesize practical design guidance and outline a future research agenda for safer and more efficient road transportation.

1st SCARline Workshop: On Operationalization of Driving Simulator Studies for Accessible In-Vehicle HMI Prototyping and Evaluation

  • Monika Szuban
  • Laura Radetzky
  • Tuğcan Önbaş
  • Ignacio Alvarez
  • Debargha Dey
  • Wendy Ju

Designing and evaluating in-vehicle Human-Machine Interfaces (HMI) requires researchers and UX designers to simultaneously navigate driving simulation software, interaction design, and user study methodology, a steep learning curve for those without a deep technical background. This workshop introduces SCARline, an open platform built atop a driving simulator that abstracts away technical complexity, letting researchers and designers focus on their research question, study design, and the in-cabin interaction they want to evaluate. A preliminary evaluation with participants from mixed disciplinary backgrounds provided initial validation and surfaced key areas for improvement, motivating this workshop as the next step in an iterative development process. Participants will be introduced to the platform architecture, guided through designing their own HMI widget, and supported in configuring a fully functional user study scenario within the simulator. The workshop invites the broader AutomotiveUI community to engage hands-on with SCARline and collectively inform its future development.

Human Centred Design for the Future of Mobility

  • Jiayu Wu
  • Chen Peng
  • Yein Song

The field of the future of mobility provides researchers, practitioners, regulators and students a brand-new canvas for envisioning emerging technologies, human behaviours, styling designs, customer services and many more details that need rethinking, reconfiguration and re-design in transportation, vehicles and related services. Emerging mobility trends such as autonomous/connected/electric vehicles, micro- and urban-air- mobility, behavioural changes including acceptance of sharing, seeking more equal/inclusive/flexible services, and responding to emotional needs, are transforming innovations. We propose a human-centred interactive workshop facilitated by a playful toolkit and learning process catering for future of mobility themes, developed for professional audiences to go through an ideation process that considers types of people, technology trends and circumstances when creating new vehicles, mobility systems and services. Outcomes will include disruptive ideas around vehicles, systems and services; brand new research agendas for future mobility; emergent mobility innovation methods, all produced through team collaboration with balanced, interdisciplinary expertise.

Understanding Motion Comfort in Automated Driving: Bridging Vehicle Dynamics, Driving Style, and Human-Machine Interaction

  • Andreas Riener
  • Paolo Pretto
  • Jaka Sodnik
  • Kristina Stojmenova Pečečnik
  • Georgios Papaioannou
  • Pavlo Bazilinskyy
  • Alexander Meschtscherjakov

Passenger comfort is emerging as a key challenge for the successful deployment and public acceptance of highly automated vehicles. Existing research has examined individual comfort determinants, including vehicle dynamics, driving style, trust, perceived safety, and human-machine interaction (HMI), although these factors have been largely investigated in isolation. Consequently, a comprehensive understanding of how they jointly influence passenger comfort remains limited. This workshop aims to bring together researchers and practitioners from the AutomotiveUI community to develop a holistic perspective on comfort in automated driving. Through interactive brainstorming, small-group discussions, and collaborative framework building, participants will identify key comfort determinants, explore the relationships between vehicle behavior, user characteristics, contextual factors, and HMI designs, and discuss methodological challenges in measuring and improving passenger comfort. The workshop will culminate in a community-driven research agenda and an initial conceptual framework to guide future interdisciplinary research on adaptive, human-centered automated mobility systems.

Beyond Take-Over Request: Exploring Human Intervention and User Interface Design for Remote Assistance in Automated Vehicles

  • Soyeon Kim
  • Maytheewat Aramrattana
  • Jonas Andersson
  • Michael Hildebrandt

Remote assistance is emerging as an important approach for supporting automated vehicles in complex, ambiguous, or unforeseen situations. While remote assistance differs from traditional take-over in terms of operator location, control authority, intervention level, and scalability, both concern how humans should be involved when automated driving systems. Building on the well-established body of take-over request (TOR) research, this workshop examines how human intervention can be conceptualised and structured in remote assistance contexts. Participants will compare TOR and remote assistance, identify key dimensions of intervention, and discuss how these dimensions translate into user interface design implications. The workshop will produce an initial framework, interface design considerations, and a research agenda for supporting effective, timely, and scalable human intervention in remote assistance.

Connecting Automotive HMI Research and Practice: A Workshop on Exploring Effective Academia-Industry Collaboration

  • Wei-Hsiang Lo
  • Naima Kiran
  • Derek Fraser
  • James M Rampton
  • Seul Chan Lee
  • Manhua Wang

Technological advances are making automotive human-machine interfaces (HMIs) a critical component of future mobility in academia, industry, and regulatory sectors. Despite substantial research activity, translating HMI research findings into automotive product development remains challenging, highlighting the need for stronger research-practice translation. Our preliminary expert interviews identified five themes related to current collaboration modes, barriers to research translation, and opportunities for stronger academia-industry partnerships. Leveraging the unique composition of the AutoUI community, which brings together researchers, practitioners, and policymakers worldwide, this workshop aims to discuss these findings and identify strategies for empowering translational research in automotive HMI. We will present insights from expert interviews, organize a mini seminar highlighting successful collaboration frameworks, and facilitate group discussions to generate actionable recommendations for bridging research and practice. Expected outcomes include refined themes, collaboration pathways, and practical guidelines to support the translation of research discoveries into product development and regulatory decision-making.

Multimodal Mental workload assessment from L0 to L5 automation: Towards a ‎valid assessment method for L5‎

  • Saeedeh Mosaferchi
  • Alireza Mortezapour
  • Gianluca Di Flumeri
  • Oscar Oviedo-Trespalacios

Mental workload is an important construct for understanding human cognitive states in conventional, automated, and highly automated ‎vehicles. As vehicle automation progresses, the role of the human changes from active driving to supervision or passive use, which leads ‎to different types of cognitive demands across different levels of automation. Existing approaches for assessing mental workload in ‎automotive contexts have mainly relied on subjective questionnaires and, to a lesser extent, performance-based measures. While these ‎methods have been widely used in conventional and partially automated driving, their suitability for highly automated environments is ‎still under discussion, as the nature of human–vehicle interaction is changing. This workshop focuses on mental workload assessment in ‎conventional, automated, and highly automated vehicles. It brings together researchers and practitioners to critically discuss current ‎measurement approaches and their limitations, and to explore a broader set of assessment methods, including questionnaires, behavioral ‎measures, and neurophysiological techniques. The aim is to create a shared understanding of how mental workload can be assessed across ‎different levels of vehicle automation and to identify directions for improving existing evaluation methods and tools used in this field.

Touchdown in the Urban Sky: Designing Human-Centered Futures for eVTOLs and City Life

  • Chenglin Liu
  • Young Woo Kim
  • Xinyan Yu
  • Zhijie Yi
  • Jiyao Wang
  • Jiangbo Yu
  • Chaozhe Jiang
  • Suhwan Jung
  • Saeedeh Mosaferchi
  • Birsen Donmez
  • Dengbo He

Urban Air Mobility (UAM), enabled by electric vertical take-off and landing vehicles (eVTOLs), is increasingly envisioned as a future layer of urban transportation. Existing UAM research has focused mainly on technical feasibility, airspace management, infrastructure, and vehicle operation, while less attention has been paid to how UAM may reshape everyday urban life, public space, human–vehicle interaction, social acceptance, and trust in highly automated aerial systems.

This workshop invites AutomotiveUI researchers, designers, practitioners, students, and policymakers to explore human-centered and trustworthy UAM futures. It combines The Urban Air Experience Probe, a lightweight eVTOL rooftop-landing simulation centered on the final approach and touchdown phase, with the Urban Air Futures Canvas that prompts participants to examine UAM from the perspectives of passengers, pilots, and bystanders. Participants will identify context-specific tensions in touchdown scenarios and translate them into societal and trust-related challenges. Drawing on AutomotiveUI work on automated driving, the workshop then supports participants in developing trust-oriented HMI concepts and governance response strategies.

SESSION: Interactive Demos

Driver-Adaptive Support Tree (DAST): From Driver Awareness to Adaptive Takeover Support

  • Jincheng Ye
  • Wei-Hsiang Lo
  • Manhua Wang

Previous takeover support has mainly relied on scene-related information, such as detected risk and remaining lead time, but these signals reflect the vehicle’s view rather than driver situation awareness, which is important for determining whether support is needed. While previous research shows the promise of using multimodal physiological data to evaluate driver situation awareness, it is still unclear how these can be integrated into real-time support systems. This demonstration then introduces Driver-Adaptive Support Tree (DAST), a real-time CARLA-based testbed that uses Lab Streaming Layer to synchronize simulator events with physiological signals and maps these data streams onto a support decision tree representing driver states. This mapping translates synchronized data into concrete support choices by linking each takeover moment to the driver’s state that requires assistance. Overall, our DAST testbed provides researchers with a repeatable platform for comparing the effects of adaptive policies in takeover scenarios.

Feeling the State: Tactile-Audio Cross-Modal Feedback for Eyes-Free Automotive User Interfaces

  • Takumi Akiyama
  • Tomokazu Furuya
  • Michiko Harazono
  • Juntaro Sakazaki
  • Takahiro Higuchi

In this study, we propose an automotive user interface (UI) that leverages tactile-audio cross-modal perception to simulate everyday tactile experiences, such as crushing a plastic bottle. Based on inputs from capacitive touch sensors, the system provides synchronized vibrotactile and auditory feedback via a vibration motor and a speaker. We developed an interactive prototype for continuous adjustment tasks in which the feedback dynamically reflects the simulated degree of physical deformation. This UI enables drivers to perceive parameter changes and interface states haptically without relying on a graphical user interface. By enabling eyes-free operation and reducing visual dependence, this system is expected to mitigate driving distractions and foster a novel user experience.

Demonstrating +Walk: Time-Budgeted Routing and Haptic Guidance for Exploratory Walking

  • Tomosuke Maeda
  • Keisuke Otaki
  • Takayoshi Yoshimura
  • Hiroyuki Sakai
  • Kouta Minamizawa

We propose +Walk, a concept that uses spare time before reaching a destination as an opportunity for exploratory walking under arrive-by constraints. To realize this concept, we built the +Walk system, a proof-of-concept implementation that combines time-budgeted routing with handheld pseudo-force haptic guidance. The routing method supports small detours while keeping the arrival time close to the planned time, and the haptic device provides turn-by-turn cues through pseudo-force sensations. +Walk opens a promising design space for time-aware, exploratory, eyes-up walking experiences.

TakeoverBench: A Benchmarking Platform for Takeover Requests (TOR) in Conditionally Automated Vehicles

  • Derick C.Z. Lee
  • Uwais Alqarni Bin Abdul Rahman
  • Yu-Xuan Tan
  • Yi-Zhen Cheng
  • Benjamin Wj Kwok
  • Kan Chen
  • Jeannie S.A. Lee

As autonomous vehicle technologies advance, increasing portions of driving control are shifting from human drivers to automated systems. Takeover situations, where control must be safely returned to the driver, remain a critical focus for safety evaluation. These handovers depend on effective takeover requests, yet existing studies are difficult to compare because they use different simulator setups, scenario designs, and performance measures. This fragmentation creates a need for a consistent workflow for designing, running, and reporting takeover experiments. In addition, developing and testing human-machine interface designs can be resource-intensive, limiting rapid comparison of alternative alert presentations. To address these limitations, we introduce TakeoverBench, an open-source benchmarking platform for autonomous vehicle takeover research. The platform integrates scenario execution, takeover alert triggering, human-machine interface testing, telemetry capture, hardware documentation, and automated report generation. Our demonstration shows how these components support consistent experimental conditions, reduce manual data-processing effort, and improve comparison across research setups.

Narrate-to-Sim: A Human Factors-Oriented Driving Simulator with Natural-Language-Supported Scenario Authoring

  • Wei-Hsiang Lo
  • Jincheng Ye
  • Manhua Wang

Driving simulators support human factors and automotive user interface research, allowing repeated testing of unsafe or future-oriented scenarios within controlled and low-risk settings. However, researchers often invest additional effort because commercial platforms represent scenarios through vehicle behavior and timing, whereas researchers define trials through experimental conditions, critical events, and cues. Human factors studies also involve physiological sensors and post-trial questionnaires, which are often managed separately, risking misalignment among simulator events, sensor data, and responses. To address these challenges, Narrate-to-Sim uses deterministic, rule-based parsing to translate supported natural-language prompts into executable scenarios and synchronize simulator logs with physiological data via Lab Streaming Layer (LSL). It features a survey module for post-trial questionnaires and allows researchers to organize trials, sensors, and questionnaires into experiment playlists for data collection. Overall, this demo presents a lightweight driving-simulator platform that reduces engineering effort and allows researchers to focus on study design.

SESSION: Videos

ARena: Augmented Reality Simulator for Automated Vehicle-Human Road User Interaction

  • Ammar Al-Taie
  • Mingyu Han
  • Ian Oakley

The advent of automated vehicles (AVs) prompted AutomotiveUI researchers to investigate how AVs can safely share the road with Human Road Users (HRUs). Researchers developed interfaces to facilitate AV-HRU interaction, e.g., on-vehicle eHMIs. However, these were mostly evaluated through online surveys with stationary participants, or virtual reality (VR) setups in small indoor settings, limiting ecological validity. This video submission showcases ARena, an open-source augmented reality (AR) simulator that projects life-sized virtual AVs, interfaces, and traffic infrastructure into outdoor environments, allowing participants to move freely. ARena enables the evaluation of diverse AV behaviours, including hazardous non-yielding scenarios that are unsafe to study using real vehicles. The platform logs key behavioural measures, including speed, cadence and gaze. ARena is extensible: Researchers can create custom traffic scenario scenes without changing logging or backend logic. The video shows how ARena supports realism for AV-HRU interaction research and advances the large-scale adoption of AVs

Towards Inclusive School Environments: Evaluating Road-Crossing Infrastructure for Autistic Adolescents in a CAVE-Based Pedestrian Simulator

  • Yue Yang
  • Zhiyi Liu
  • Elizabeth Sheppard
  • Yee Mun Lee

Adolescence is a key stage when independent travel becomes more common. However, road crossing can remain challenging for autistic adolescents and those with other special educational needs (SEN), particularly where crossing support is limited or ambiguous. This video submission presents an ongoing study evaluating road-crossing infrastructure for inclusive mobility conducted in a CAVE-based pedestrian simulator that replicates the roads outside SEN schools in Leeds, UK. The study compares a no-interface baseline with three infrastructure designs: a zebra crossing, a pelican crossing, and a projection-enhanced pelican crossing. Sixty-four adolescents aged 11-13 years were recruited, including 32 autistic and 32 typically developing participants, with groups balanced by gender. Participants completed crossing trials across two environments: a two-lane road and a two-lane road with a cycle lane, simulating two real school environments in Leeds. The study aims to provide evidence-based recommendations for inclusive school crossing infrastructure and to support local traffic engineers in designing safer road environments for children with diverse needs.

Surf Road: A Fusion of Personal and Shared Mobility for Seamless Urban Experience

  • Kyeongmin Ha
  • Huiseo Yun
  • Yuna Cho
  • Kyung Yun Choi

As personal mobility (PM) ridership surges, contemporary urban planning focuses heavily on dedicating isolated lanes, often overlooking the continuity of the seamless transit experience. To address these fragmented transfer points between public transit and micro-mobility, this paper introduces ‘Surf Road’, a novel paradigm in urban transportation. While modern cities are physically connected, a rider’s journey is often abruptly disrupted at the boundaries of macro-infrastructure. Accompanied by a video demonstration, we present a symbiotic PM system that organically docks with moving tram networks, transforming a stagnant commute into a playful, continuous “urban surfing” experience. Without requiring prohibitive infrastructure overhauls, Surf Road seamlessly coexists with existing transit grids to deliver a high-continuity user experience (UX), offering a futuristic framework for human-infrastructure symbiosis.

Wait to Win: Strategic Departure Timing for Multi-Stop Navigation

  • Cansu Demir
  • Fabian Köhnke
  • Breanna Lei Rose G. Dulay
  • Christian Borgelt
  • Alexander Meschtscherjakov

Most navigation systems tell users how to arrive fastest if they leave now. Yet in flexible multi-stop journeys, the best strategy may be counterintuitive: waiting briefly, leaving later, or reordering stops can reduce exposure to predicted congestion and improve the overall journey. This video presents a navigation concept for strategic departure timing. Through a narrated in-vehicle scenario, it demonstrates how a navigation system compares immediate departure with alternative timing strategies. A proof-of-concept prototype supports the scenario by using temporal activity patterns as time-dependent delay signals and a Genetic Network Programming-based planner to explore route order, departure timing, and dwell-time decisions. Finally, we highlight future design opportunities for in-vehicle intelligent agents to transparently communicate the rationale, benefits and alternatives behind recommendations.

Not All Situation Awareness Is the Same: Decoding Driver Awareness with Physiological Signals

  • Wei-Hsiang Lo
  • Jincheng Ye
  • Manhua Wang

Takeover warnings in conditionally automated vehicles are typically triggered when the automated driving system detects that it is approaching its operational limits. However, without evidence of what drivers have perceived, interpreted, and anticipated about traffic events, such warnings may not provide precise support. While physiological modeling can provide non-intrusive, real-time evidence of driver situation awareness (SA), previous studies using physiological signals often represent driver SA using a single score, obscuring whether support should address spatial risk location or temporal hazard progression. This video presents target-specific SA modeling across four SA targets organized by these two event dimensions: forward-path and adjacent-lane SA for spatial risk location, and materialized- and unmaterialized-hazard SA for temporal hazard progression. In the video, we present an adaptive takeover support strategy based on target-specific SA modeling and our preliminary video-based takeover study. Overall, we demonstrate how fine-grained driver SA assessment can guide adaptive takeover support.

Dialog with trucks – A driving simulator study exploring situationally-aware conversational agents

  • Johanna Vännström
  • Andreas Absér
  • Jacob Weilandt
  • Azra Habibovic

Current AI-based conversational agents (CAs) largely lack situational awareness, limiting their ability to understand driving context, driver state, and immediate driver needs. Consequently, the use of CA may increase drivers’ cognitive load and impair safety and user experience. This study investigates the role of situationally aware CA in long-haul trucks and how such CA should be designed to support drivers in an efficient way. The insights were gathered through a Wizard-of-Oz driving simulator study exploring two CA concepts. The results show that CA are well-suited for strategic tasks, could be useful for some tactical tasks depending on the cognitive load, and are generally inappropriate at the operational level, where they interfere with core driving actions. Effective CA design must prioritize driving as the primary task, adapt interaction timing to drivers’ cognitive load, and ensure transparency and predictability to build trust.

SESSION: Student Research Track

Student Research Track: Drivers’ Correctness on Cue-Level Situation Awareness Probes: The Roles of Spatial Direction and Event State During Automated Driving Takeovers

  • Jincheng Ye
  • Wei-Hsiang Lo
  • Manhua Wang

Drivers in conditionally automated vehicles must rebuild situation awareness (SA) when automation reaches its limits. Under the attention-SA model, rebuilding requires sampling driving-scene cues after takeover requests. Non-driving-related tasks can divert attention, requiring assessments to identify which cues drivers sampled. Prior scene- and object-level measures omit cue-level information about what drivers perceived, interpreted, and anticipated: the former provide only scene-wide judgments; the latter report detection alone. To address this gap, 33 drivers completed a video-based study assessing takeover-relevant cue-level SA along two dimensions: Spatial Direction (longitudinal versus lateral) and Event State (precursor versus materialized). A generalized linear mixed-effects model analyzed probe correctness. Results showed that drivers answered lateral-cue probes more accurately than longitudinal-cue probes and materialized-hazard probes more accurately than hazardous-precursor probes. The materialized-versus-precursor difference appeared only for lateral probes; longitudinal-probe correctness was similar across levels. These findings may inform development of cue-aware takeover support for next-generation automated vehicles.

Student Research Track: Toward a Restorative Robotaxi: Psychological Benefits of Nature Visuals within Autonomous Vehicle Navigational User Interfaces

  • Ryan Lee

Autonomous vehicles (AV’s) can improve transportation accessibility and safety, yet public adoption remains a challenge for carmakers. Visual connection to nature is known to reduce anxiety, improve mood, restore mental bandwidth, and create more desirable environments for humans; Edward Wilson’s Biophilia Hypothesis holds that an essential aspect of human well-being is a connection to the natural world. Building on prior research on natural elements in interior spaces, this study hypothesizes that a navigational user interface (NUI) incorporating nature-based visuals would increase AV passenger comfort in terms of positive emotion, perceived restoration, and connection to nature. In the study, 12 participants viewed a virtual reality simulation to evaluate the effect of three nature visuals (Water, Wildlife, and Weather) within the vehicle’s NUI. Participants reported a 74% increase in positive affect (Weather), a 57% increase in perceived restoration (Weather), and a 95% increase in connection to nature (Wildlife), compared to a blank interface (Friedman tests, all p < .01). Participants most preferred a depiction of natural cycles, reproducing sunlight and environmental change, and the movement of water ripples. By incorporating natural elements into NUI’s, this study introduces one strategy to expand AV interactions into a psychologically preferable encounter.

Student Research Track: Designing Multimodal Takeover Interfaces to Support Driver Readiness in L2/L3 Automated Vehicles

  • Prize Thomas Mathew
  • Srikar Reddy Akireddigari

Transitions from automated to manual control remain a critical challenge in L2/L3 automated vehicles, where sudden or poorly explained takeover requests can create confusion, anxiety, delayed reactions, and reduced trust. This student research project explores how automotive human-machine interfaces (HMIs) can support driver readiness during system-to-driver handover. In this paper, takeover refers to a system-initiated request for the human driver to resume manual control, while handover refers to the broader transition of control from automation back to the driver. Driver readiness is understood as the driver’s preparedness to reorient to the driving task, understand why intervention is needed, and begin manual control. The work originated in a graduate Human-Computer Interaction (HCI) course and followed a user-centered design process including background research, qualitative user research, persona development, user stories, ideation, low- and high-fidelity prototyping, and immersive concept visualization. Based on insights from cautious commuters and technology-aware drivers, we designed the Calm Handover System, a specific multimodal takeover interface that combines phased visual alerts, predictive takeover-zone visualization, auditory cues, and haptic feedback. The contribution of the work lies in reframing takeover as a staged, explainable, and design-led transition rather than a single sudden alert. The project is presented as an early-stage student design exploration rather than a validated experimental system.

Student Research Track: How Distance Display Designs Influence Driver Attention in Forward Collision Warnings: An Eye-Tracking Study

  • Pei-Ru Chen
  • Jo-Yu Kuo

This study evaluated how visual variables in Forward Collision Warning (FCW) following-distance designs were associated with drivers’ visual attention. Four display designs were tested in a prerecorded highway-driving scenario with two non-driving-related tasks. Eye-tracking data from 15 participants were analyzed using heatmap visualization and linear mixed-effects models. Thin-stripe was associated with a shorter time to first fixation on the FCW area of interest (AOI) than Wide-stripe and a higher overall glance frequency than the other displays. Percentage dwell time (PDT) revealed AOI-specific viewing patterns: PDT in the FCW AOI was higher for Thin-stripe and Elliptical than for Wide-stripe, whereas Radar showed greater PDT in the WINDOW AOI than the other conditions. Results suggest distinct gaze patterns across displays, potentially related to texture and orientation, but remain exploratory because display order was fixed and visual variables were not independently manipulated.

Student Research Track: Hack on the Road: Can LLM-Based Driving Agents Improve Driver Response During Automated Vehicle Cyber-Attacks?

  • Naima Kiran
  • Seulchan Lee

Automated vehicles (AVs) increasingly rely on connected communication systems, which make them vulnerable to cyber-attacks. During such events, drivers may not understand the situation and might need additional assistance. Although driving agents can provide warnings, large language model (LLM)-based driving agents may offer deeper explanation and follow-up support. Prior work has examined cyber-attacks in vehicles and the role of in-vehicle intelligent agents, but limited research has investigated how different agents specifically LLM-based driving agents affect driver response during AV cyber-attacks. This ongoing study proposes a driving simulator experiment comparing low-critical and high-critical cyber-attacks in three agent conditions: no agent, a rule-based driving agent, and an LLM-based driving agent. The rule-based driving agent provides short cyber-attack warnings and action instructions, while the LLM-based driving agent provides conversational explanations and follow-up question-answer support. Behavioral and subjective measures will be collected. The expected contribution has implications in the field of Human-computer interaction for the future design of driving agents according to the risk of cyber-attacks.

​Student Research Track: Letting the Automated Vehicle Explain Its Own Errors: A Simulator Testbed for Passenger-Facing Explanation HMIs in SOTIF Error Situations

  • Taewan Kim
  • Soeun Park
  • Eunchae Song
  • Yoonseo Cho
  • Chaeyeon Kim
  • Nayoung Kim
  • Jongwon Choe
  • Yunyoung Choi
  • Seojin Lee
  • Minchae Kim
  • Dokshin Lim

A fully automated (SAE L5) vehicle can obey every traffic rule and still behave near-erroneously, and a passenger who cannot tell why loses situation awareness (SA) to the black-box driving stack, degrading the ride. Prior natural-language explanations target drivers or stop at model interpretability, not a passenger-facing account of the vehicle’s own error. This paper designs such an explainable-AI (XAI) interface and builds a simulator testbed to validate it before any human study. We frame a scenario’s error as the functional and output insufficiency (FI/OI) defined by ISO 21448 Safety of the Intended Functionality (SOTIF), and organize a Vision-Language-Action (VLA) model’s reasoning trace into Endsley’s three SA stages. The first contribution is a reusable design that maps this reasoning onto SA stages so the vehicle explains its own FI/OI. The second is a Passenger-in-the-Loop testbed coupling CARLA, a 6-DOF motion platform, and live visual and voice Human-Machine Interfaces (HMIs) over WebSocket, with six metrics as a scenario quality-assurance instrument. In a human-free dry run of 100 replays per scenario, the roundabout-deadlock scenario ran collision-free with deterministic metrics (CV  ≤  0.4%), while the aquaplaning scenario fired its terrain-transition events in every replay and is characterized by its multi-run distribution. We outline a follow-up human-subject study to test affect induction and user experience.

Student Research Track: Towards Low-Cost Driver Supervision: Evaluating a Smartphone Interface for Driver Inattention Monitoring in Simulated Driving

  • Yi-Zhen Cheng
  • Yu-Xuan Tan
  • Uwais Alqarni Bin Abdul Rahman
  • Derick C.Z. Lee
  • Kan Chen
  • Jeannie S.A. Lee

Driver assistance and partially automated driving can reduce active control demands on drivers, but they may become distracted or fatigued and must remain ready to supervise or re-engage. Although driver-monitoring systems have been studied extensively, direct camera-based systems are often vehicle-integrated and not uniformly available. We present a low-cost, supplementary Android smartphone interface that uses the smartphone’s front-facing camera as a supplementary driver-monitoring and alerting interface. The prototype combines on-device face analysis and TensorFlow Lite object detection to identify six states: attentive baseline, yawning, prolonged eye closure, phone-like interaction, reading, and face-not-detected. The system was evaluated in a controlled pilot study with 30 participants across 180 trials, measuring classification performance, alert latency, and post-alert recovery. The system detected multiple target behaviours, with strongest performance for prolonged eye closure and face-not-detected, while phone-like interaction and reading remained more challenging. This work contributes early HCI evidence for using smartphones as interactive driver-supervision interfaces, highlighting trade-offs between low-cost sensing, alert timing, user trust, intrusiveness, and attention recovery.

Student Research Track: Design Beyond Ownership: A Framework for Translating Emerging Mobility Conditions into Early-Stage Vehicle Design

  • Yein Song

Mobility systems are reshaping how vehicles are accessed, shared, and maintained, yet vehicle development remains largely grounded in assumptions established for private ownership. As shared mobility, autonomous services, and fleet-based operations expand, vehicles increasingly operate under conditions characterized by multiple users, repeated short-term use, and operator-managed care. However, limited attention has been given to translating these changing operational contexts into vehicle design during concept development. This paper investigates how recurring operational conditions can inform early-stage vehicle design. Through a literature review and comparative practice review, the study identifies common operational conditions across emerging mobility systems and proposes a structured translation framework that interprets these conditions through interaction and formulates initial design criteria. The findings suggest that recurring operational conditions provide a stronger basis for early-stage vehicle design than mobility service categories alone. The proposed framework offers a systematic approach for incorporating emerging mobility conditions into vehicle design during concept development, contributing to closer integration between mobility transition, Automotive HCI, and automotive design.

Student Research Track: Observing School-Age Child Group Crossings from Bird’s-Eye View for Behavioural Research

  • Simon Schwertner
  • Alice Rollwagen
  • Andreas Riener

Autonomous vehicles need to respond safely to pedestrians, yet the behavior of school-age children remains difficult to characterize and is only weakly represented in many datasets and prediction-oriented research streams. Prior work has shown that children differ from adults in attention, timing, and decision-making during street crossing, and that current pedestrian detection systems can also perform worse on children than on adults. At the same time, much of the existing literature on pedestrian intention prediction focuses on adult pedestrians, egocentric traffic scenes, or individual behavior rather than small child groups.

This work-in-progress examines how school-age child group crossings can be described from drone-based bird’s-eye-view recordings for qualitative behavioural research in automated driving contexts. Based on a controlled field study, the paper presents a structured observational account of single-directional and bidirectional child crossing scenes, focusing on waiting, scanning, initiation, following, cohesion, and lateral movement patterns. Across scenes, crossings often appeared to be socially organized, with a small number of children initiating movement while others followed with limited visible safety checks. Rather than proposing a predictive model, the paper offers an initial descriptive basis for future work on underrepresented pedestrian behaviour, trajectory analysis, and child-centered modelling questions.