Personal Space of Autonomous Car’s Passengers Sitting in the Driver’s Seat

Abstract

This article deals with the specific context of an autonomous car navigating in an urban center within a shared space between pedestrians and cars. The driver delegates the control to the autonomous system while remaining seated in the driver's seat. The proposed study aims at giving a first insight into the definition of human perception of space applied to vehicles by testing the existence of a personal space around the car. It aims at measuring proxemic information about the driver's comfort zone in such conditions. Proxemics, or human perception of space, has been largely explored when applied to humans or to robots, leading to the concept of personal space, but poorly when applied to vehicles. In this article, we highlight the existence and the characteristics of a zone of comfort around the car which is not correlated to the risk of a collision between the car and other road users. Our experiment includes 19 volunteers using a virtual reality headset to look at 30 scenarios filmed in 360°from the point of view of a passenger sitting in the driver's seat of an autonomous car. They were asked to say "stop" when they felt discomfort visualizing the scenarios.As said, the scenarios voluntarily avoid collision effect as we do not want to measure fear but discomfort. The scenarios involve one or three pedestrians walking past the car at different distances from the wings of the car, relative to the direction of motion of the car, on both sides. The car is either static or moving straight forward at different speeds. The results indicate the existence of a comfort zone around the car in which intrusion causes discomfort. The size of the comfort zone is sensitive neither to the side of the car where the pedestrian passes nor to the number of pedestrians. In contrast, the feeling of discomfort is relative to the car's motion (static or moving). Another outcome from this study is an illustration of the usage of first person 360°video and a virtual reality headset to evaluate feelings of a passenger within an autonomous car.

Risk Assessment by a Passenger of an Autonomous Vehicle Among Pedestrians: Relationship Between Subjective and Physiological Measures

“…These findings are compatible with the concept of the “safe field of travel” that was introduced by Gibson and Crooks ( 1938 ), according to which an individual represents a dynamic area in which their vehicle can navigate safely. In comparison with the experiment conducted by Ferrier-Barbut et al ( 2018 ), who used a virtual-reality helmet to test the impact of proximity between pedestrians and a vehicle, this experiment utilized a driving simulator that lacked a physical vehicle cab, which may have made it difficult to estimate the vehicle's width and its lateral distance from object (Mecheri and Lobjois, 2018 ). Although Walker et al ( 2019b ) demonstrated that medium-level driving simulators remain appropriate for the study of risk perception, the lack of a physical cab simulator and the absence of real danger may have limited the participants' abilities to gauge their proximity to the pedestrians.…”

“…In this case, new metrics must be used to study risk perception. Ferrier-Barbut et al ( 2018 ) revealed the existence of a comfort zone that is perceived by the passenger of an autonomous vehicle when the vehicle is passing close to a pedestrian. This suggests that absolute distance is a factor in the passenger's perception.…”

Intersection AEB implementation strategies for left turn across path crashes

“…A large safety zone can compensate for these and ensure more reliable activation in crash conditions (better true positive performance) but might also trigger premature activation in passing conditions (worse false positive performance). This makes the safety zone an important yet not well-documented parameter for the expected benefits and merits further investigation for its effects on balancing real-world true positive and false positive performance as well as its perceived subjective benefit and nuisance as, for example, explored in Ferrier- Barbut et al (2018) for pedestrian passing distances.…”

A Pilot Study on the Dynamics of Online Risk Assessment by the Passenger of a Self-driving Car Among Pedestrians

“…These considerations raise the question of the perceived comfort or risk on board an autonomous vehicle during a travel among other road users. Unfortunately, there are very few studies in the literature on passenger risk perception in an autonomous vehicle (e.g., [7][8][9]). We propose here to study this phenomenon in a dynamic context using a driving simulator.…”