The effect of haptic support systems on driver performance: A literature survey

A large number of haptic driver support systems have been described in the scientific literature. However, there is little consensus regarding the design, evaluation methods, and effectiveness of these systems. This literature survey aimed to investigate: (1) what haptic systems (in terms of function, haptic signal, channel, and supported task) have been experimentally tested, (2) how these haptic systems have been evaluated, and (3) their reported effects on driver performance and behaviour. We reviewed empirical research in which participants had to drive a vehicle in a real or simulated environment, were able to control the heading and/or speed of the vehicle, and a haptic signal was provided to them. The results indicated that a clear distinction can be made between warning systems (using vibrations) and guidance systems (using continuous forces). Studies typically used reaction time measures for evaluating warning systems and vehicle-centred performance measures for evaluating guidance systems. In general, haptic warning systems reduced the reaction time of a driver compared to no warnings, although these systems may cause annoyance. Guidance systems generally improved the performance of drivers compared to non-aided driving, but these systems may suffer from after-effects. Longitudinal research is needed to investigate the transfer and retention of effects caused by haptic support systems

Should drivers be operating within an automation-free bandwidth?: Evaluating haptic steering support systems with different levels of authority

Objective: The aim of this study was to compare continuous versus bandwidth haptic steering guidance in terms of lane-keeping behavior, aftereffects, and satisfaction. Background: An important human factors question is whether operators should be supported continuously or only when tolerance limits are exceeded. We aimed to clarify this issue for haptic steering guidance by investigating costs and benefits of both approaches in a driving simulator. Methods: Thirty-two participants drove five trials, each with a different level of haptic support: no guidance (Manual); guidance outside a 0.5-m bandwidth (Band1); a hysteresis version of Band1, which guided back to the lane center once triggered (Band2); continuous guidance (Cont); and Cont with double feedback gain (ContS). Participants performed a reaction time task while driving. Toward the end of each trial, the guidance was unexpectedly disabled to investigate aftereffects. Results: All four guidance systems prevented large lateral errors (>0.7 m). Cont and especially ContS yielded smaller lateral errors and higher time to line crossing than Manual, Band1, and Band2. Cont and ContS yielded short-lasting aftereffects, whereas Band1 and Band2 did not. Cont yielded higher self-reported satisfaction and faster reaction times than Band1. Conclusions: Continuous and bandwidth guidance both prevent large driver errors. Continuous guidance yields improved performance and satisfaction over bandwidth guidance at the cost of aftereffects and variability in driver torque (indicating human–automation conflicts). Application: The presented results are useful for designers of haptic guidance systems and support critical thinking about the costs and benefits of automation support systems.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Biomechatronics & Human-Machine ControlMedical Instruments & Bio-Inspired Technolog

The effect of haptic support systems on driver performance: A literature survey

A large number of haptic driver support systems have been described in the scientific literature. However, there is little consensus regarding the design, evaluation methods, and effectiveness of these systems. This literature survey aimed to investigate: (1) what haptic systems (in terms of function, haptic signal, channel, and supported task) have been experimentally tested, (2) how these haptic systems have been evaluated, and (3) their reported effects on driver performance and behaviour. We reviewed empirical research in which participants had to drive a vehicle in a real or simulated environment, were able to control the heading and/or speed of the vehicle, and a haptic signal was provided to them. The results indicated that a clear distinction can be made between warning systems (using vibrations) and guidance systems (using continuous forces). Studies typically used reaction time measures for evaluating warning systems and vehicle-centred performance measures for evaluating guidance systems. In general, haptic warning systems reduced the reaction time of a driver compared to no warnings, although these systems may cause annoyance. Guidance systems generally improved the performance of drivers compared to non-aided driving, but these systems may suffer from after-effects. Longitudinal research is needed to investigate the transfer and retention of effects caused by haptic support systems.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Biomechatronics & Human-Machine Contro

The design of a vibrotactile seat for conveying take-over requests in automated driving

The driver of a conditionally automated car is not required to permanently monitor the outside environment, but needs to take over control whenever the automation issues a “request to intervene” (i.e., take-over request). If the driver misses the take-over request or does not respond in a timely and correct manner, a take-over could result in a safety-critical scenario. Traditionally, warnings in vehicles are conveyed by visual and auditory displays, though recently it has been argued that vibrotactile stimuli could also be a viable approach to present a takeover request to the driver. In this paper, we present a vibrotactile seat designed to convey dynamic vibration patterns to the driver. The seat incorporates 48 vibration motors (eccentric mass rotation) that can be individually controlled. One 6 × 4 matrix, with an average inter-motor distance of approximately 4 cm, is located in the seat back and one in the seat bottom. The DC-voltage to the motors is controlled by three Pulse Width Modulation (PWM) drivers, which in turn are controlled by an Arduino microcontroller. A study with 12 participants was conducted to investigate (1) at which vibration intensity participants find a vibratory stimulus annoying and whether this threshold changes over time, (2) how well participants are able to discriminate vibratory stimuli as a function of spatial separation, and (3) which of six dynamic vibration patterns are regarded as most satisfying. Results showed that participants’ annoyance threshold reduced when they were repeatedly exposed to vibrotactile stimuli. Second, the percentage of correct responses in the two-point discrimination test increased significantly with increasing inter-stimuli distance (i.e., from 4 to 20 cm). Third, participants seemed to be more satisfied when more motors were activated simultaneously (i.e., more spatial overlap). Overall, the results suggest that participants are well able to perceive vibrotractile stimuli in the driver seat. However, the results suggest that repetitive exposure to vibrotactile stimuli may evoke annoyance, a finding that should be taken into account in future designs of vibrotactile displays. Future studies should investigate the possibility to convey complex messages via the vibration seat.</p

The design of a vibrotactile seat for conveying take-over requests in automated driving

The driver of a conditionally automated car is not required to permanently monitor the outside environment, but needs to take over control whenever the automation issues a “request to intervene” (i.e., take-over request). If the driver misses the take-over request or does not respond in a timely and correct manner, a take-over could result in a safety-critical scenario. Traditionally, warnings in vehicles are conveyed by visual and auditory displays, though recently it has been argued that vibrotactile stimuli could also be a viable approach to present a takeover request to the driver. In this paper, we present a vibrotactile seat designed to convey dynamic vibration patterns to the driver. The seat incorporates 48 vibration motors (eccentric mass rotation) that can be individually controlled. One 6 × 4 matrix, with an average inter-motor distance of approximately 4 cm, is located in the seat back and one in the seat bottom. The DC-voltage to the motors is controlled by three Pulse Width Modulation (PWM) drivers, which in turn are controlled by an Arduino microcontroller. A study with 12 participants was conducted to investigate (1) at which vibration intensity participants find a vibratory stimulus annoying and whether this threshold changes over time, (2) how well participants are able to discriminate vibratory stimuli as a function of spatial separation, and (3) which of six dynamic vibration patterns are regarded as most satisfying. Results showed that participants’ annoyance threshold reduced when they were repeatedly exposed to vibrotactile stimuli. Second, the percentage of correct responses in the two-point discrimination test increased significantly with increasing inter-stimuli distance (i.e., from 4 to 20 cm). Third, participants seemed to be more satisfied when more motors were activated simultaneously (i.e., more spatial overlap). Overall, the results suggest that participants are well able to perceive vibrotractile stimuli in the driver seat. However, the results suggest that repetitive exposure to vibrotactile stimuli may evoke annoyance, a finding that should be taken into account in future designs of vibrotactile displays. Future studies should investigate the possibility to convey complex messages via the vibration seat.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Biomechatronics & Human-Machine Contro

Designing an AI-companion to support the driver in highly autonomous cars

In this paper, we propose a model for an AI-Companion for conditionally automated cars, able to maintain awareness of the driver regarding the environment but also to able design take-over requests (TOR) on the fly, with the goal of better support the driver in case of a disengagement. Our AI-Companion would interact with the driver in two ways: first, it could provide feedback to the driver in order to raise the driver Situation Awareness (SA), prevent them to get out of the supervision loop and so, improve takeover during critical situations by decreasing their cognitive workload. Second, in the case of TOR with a smart choice of modalities for convey the request to the driver. In particular, the AI-Companion can interact with the driver using many modalities, such as visual messages (warning lights, images, text, etc.), auditory signals (sound, speech, etc.) and haptic technologies (vibrations in different parts of the seat: back, headrest, etc.). The ultimate goal of the proposed approach is to design smart HMIs in semi-autonomous vehicles that are able to understand 1) the user state and fitness to drive, 2) the current external situation (vehicle status and behavior) in order to minimize the automation surprise and maximizing safety and trust, and 3) leverage AI to provide adaptive TOR and useful feedback to the driver

Turmoil behind the automated wheel:an embodied perspective on current HMI developments in partially automated vehicles

\u3cp\u3eCars that include combinations of automated functions, such as Adaptive Cruise Control (ACC) and Lane Keeping (LK), are becoming more and more available to consumers, and higher levels of automation are under development. In the use of these systems, the role of the driver is changing. This new interaction between the driver and the vehicle may result in several human factors problems if not sufficiently supported. These issues include driver distraction, loss of situational awareness and high workload during mode transitions. A large conceptual gap exists on how we can create safe, efficient and fluent interactions between the car and driver both during automation and mode transitions. This study looks at different HMIs from a new perspective: Embodied Interaction. The results of this study identify design spaces that are currently underutilized and may contribute to safe and fluent driver support systems in partially automated cars.\u3c/p\u3