Cyriel Diels

Self-driving carsickness

This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the drivers perspective, the direct benefits of this technology are considered increased comfort and productivity. However, we here show that the envisaged scenarios all lead to an increased risk of motion sickness. As such, the benefits this technology is assumed to bring may not be capitalised on, in particular by those already susceptible to motion sickness. This can negatively affect user acceptance and uptake and, in turn, limit the potential socioeconomic benefits that this emerging technology may provide. Following a discussion on the causes of motion sickness in the context of self-driving cars, we present guidelines to steer the design and development of automated vehicle technologies. The aim is to limit or avoid the impact of motion sickness and ultimately promote the uptake of self-driving cars. Attention is also given to less well known consequences of motion sickness, in particular negative aftereffects such as postural instability, and detrimental effects on task performance and how this may impact the use and design of self-driving cars. We conclude that basic perceptual mechanisms need to be considered in the design process whereby self-driving cars cannot simply be thought of as living rooms, offices, or entertainment venues on wheels.

Frequency Characteristics of Visually Induced Motion Sickness

Objective: The aim of this study was to explore the frequency response of visually induced motion sickness (VIMS) for oscillating linear motion in the fore-and-aft axis. Background: Simulators, virtual environments, and commercially available video games that create an illusion of self-motion are often reported to induce the symptoms seen in response to true motion. Often this human response can be the limiting factor in the acceptability and usability of such systems. Whereas motion sickness in physically moving environments is known to peak at an oscillation frequency around 0.2 Hz, it has recently been suggested that VIMS peaks at around 0.06 Hz following the proposal that the summed response of the visual and vestibular self-motion systems is maximized at this frequency. Methods: We exposed 24 participants to random dot optical flow patterns simulating oscillating fore-and-aft motion within the frequency range of 0.025 to 1.6 Hz. Before and after each 20-min exposure, VIMS was assessed with the Simulator Sickness Questionnaire. Also, a standard motion sickness scale was used to rate symptoms at 1-min intervals during each trial. Results: VIMS peaked between 0.2 and 0.4 Hz with a reducing effect at lower and higher frequencies. Conclusion: The numerical prediction of the “crossover frequency” hypothesis, and the design guidance curve previously proposed, cannot be accepted when the symptoms are purely visually induced. Application: In conditions in which stationary observers are exposed to optical flow that simulates oscillating fore-and-aft motion, frequencies around 0.2 to 0.4 Hz should be avoided.

Visually induced motion sickness: Single- versus dual-axis motion

The majority of studies into visually induced motion sickness (VIMS) either use complex motion scenarios or are limited to single-axis motion. This study compared VIMS during single- and dual-axis motion. Twelve participants were exposed to (i) oscillating roll motion, (ii) linear motion in the fore-and-aft axis, and (iii) spiral motion, i.e. the summed direction of both of these flow vectors. Increased sensory conflict during exposure to spiral motion was hypothesised to increase the level of VIMS compared with exposure to its constituent motion patterns in isolation. Unexpectedly, spiral motion was not found to be more provocative than either of the two single-axis motion patterns, and this finding appears to be inconsistent with VIMS being determined by simple summation of the provocative stimuli. In the spiral motion condition, an atypical decrease in VIMS was observed during exposure, which was consistently preceded by a reduction in reported vection. It was hypothesised that the abstract nature as well as the unusual motion profile in the spiral motion condition may have rendered the stimulus increasingly ‘improbable’ and ultimately being disregarded, or ‘quarantined’, as an orientation cue by the central nervous system. The results are discussed in the context of methodological consequences for VIMS research and potential limitations of the use of abstract stimuli.

User interface considerations to prevent self-driving carsickness

Self-driving cars have the potential to bring significant benefits to drivers and society at large. However, all envisaged scenarios are predicted to increase the risk of motion sickness. This will negatively affect user acceptance and uptake and hence negate the benefits of this technology. Here we discuss the impact of the user interface design in particular, focusing on display size, position, and content and the relationship with the degree of sensory conflict and ability to anticipate the future motion trajectory of the vehicle, two key determinants of motion sickness in general. Following initial design recommendations, we provide a research agenda to accelerate our understanding of self-driving cars in the context of the scenarios currently proposed. We conclude that basic perceptual mechanisms need to be considered in the design process whereby self-driving cars cannot simply be thought of as living rooms, offices, or entertainment venues on wheels.

Towards Adaptive Ambient In-Vehicle Displays and Interactions: Insights and Design Guidelines from the 2015 AutomotiveUI Dedicated Workshop

Informing a driver of a vehicle’s changing state and environment is a major challenge that grows with the introduction of in-vehicle assistant and infotainment systems. Even in the age of automation, the human will need to be in the loop for monitoring, taking over control, or making decisions. In these cases, poorly designed systems could lead to needless attentional demands imparted on the driver, taking it away from the primary driving task. Existing systems are offering simple and often unspecific alerts, leaving the human with the demanding task of identifying, localizing, and understanding the problem. Ideally, such systems should communicate information in a way that conveys its relevance and urgency. Specifically, information useful to promote driver safety should be conveyed as effective calls for action, while information not pertaining to safety (therefore less important) should be conveyed in ways that do not jeopardize driver attention. Adaptive ambient displays and peripheral interactions have the potential to provide superior solutions and could serve to unobtrusively present information, to shift the driver’s attention according to changing task demands, or enable a driver to react without losing the focus on the primary task. In order to build a common understanding across researchers and practitioners from different fields, we held a “Workshop on Adaptive Ambient In-Vehicle Displays and Interactions” at the AutomotiveUI‘15 conference. In this chapter, we discuss the outcomes of this workshop, provide examples of possible applications now or in the future and conclude with challenges in developing or using adaptive ambient interactions.

Motion Sickness in Automated Vehicles: The Elephant in the Room

Automation disuse and associated loss of automation benefits may occur if users of automated vehicles experience motion sickness. Compared to conventional vehicles, motion sickness will be of greater concern due to the absence of vehicle control and the anticipated engagement in non-driving tasks. Furthermore, future users are expected to be less tolerant to the occurrence of motion sickness in automated vehicles compared to other means of transport. The risk of motion sickness may be manageable if we understand underlying causes and design our vehicles and driver-vehicle interactions appropriately. Guided by three fundamental principles, an initial set of design considerations are provided reflecting the incorporation of basic perceptual mechanisms.

Compatibility between Trust and Non-Driving Related Tasks in UI Design for Highly and Fully Automated Driving

Acceptance of highly and fully automated vehicles will depend on system trust and the ability to comfortably engage in non-driving related tasks (NDRT). We here hypothesize a potential trade-off between the two. The paper describes the development of two UI concepts based on trust factors derived from the literature and benchmarking of current (concept) UIs to explore the balance between trust and engagement in NDRT. The concepts were inspired by the Valeo Mobius User Interface concept. The level of intrusiveness of trust related information was the key parameter differentiating the two concepts and was manipulated by adopting a single head up display versus a distributed display configuration also including a central console display. A comparative simulator study is underway to explore the balance between trust and comfortable engagement in NDRT and areas of future research are discussed.

Looking forward : In-vehicle auxiliary display positioning affects carsickness

Carsickness is associated with a mismatch between actual and anticipated sensory signals. Occupants of automated vehicles, especially when using a display, are at higher risk of becoming carsick than drivers of conventional vehicles. This study aimed to evaluate the impact of positioning of in-vehicle displays, and subsequent available peripheral vision, on carsickness of passengers. We hypothesized that increased peripheral vision during display use would reduce carsickness. Seated in the front passenger seat 18 participants were driven a 15-min long slalom on two occasions while performing a continuous visual search-task. The display was positioned either at 1) eye-height in front of the windscreen, allowing peripheral view on the outside world, and 2) the height of the glove compartment, allowing only limited view on the outside world. Motion sickness was reported at 1-min intervals. Using a display at windscreen height resulted in less carsickness compared to a display at glove compartment height.

Information Expectations in Highly and Fully Automated Vehicles

Vehicle automation fundamentally changes the relationship with our vehicles whereby system trust and occupant comfort will become key user requirements. We here explored what information users expect to receive across a wide range of traffic scenarios in urban and peri-urban environments for both highly and fully automated vehicles. Results indicated that users expected the HMI to provide information to promote system transparency, comprehensibility, and predictability. Visual presentation using Head Up Display technologies was the preferred method but older users in particular expressed a preference for auditory interfaces. In hazardous or uncertain situations, participants expressed a desire to be able to override or confirm vehicle actions. Results indicated that information requirements might however change with experience signifying the potential role for adaptive and configurable HMI solutions for future vehicles.

Human-Machine Interface Design Development for Connected and Cooperative Vehicle Features

This paper discusses the design and evaluation of a number of connected and cooperative vehicle sign designs which have been developed within the UK Connected Intelligent Transport Environment project (UKCITE). As part of the first phase of the project, the sign design of four different applications were developed and evaluated: Emergency Electronic Brake Lights, Emergency Vehicle Warning, Traffic Condition Warning, and Road Works Warning. Whereas some of the feature made use of existing signs (e.g. road works warning), other applications required new signs. Appropriateness of the signs were evaluated by 21 participants who were shown videos of relevant traffic scenarios with the different signs displayed at appropriate moments. Results are discussed in the context of their appropriateness and suggest that existing standard signs may not appropriately represent new connected vehicle features requiring new design solutions.