Motorcycle rider perception response times to abrupt- and gradual-onset hazards in a simulator

• Main Author: Wong, Grace Miao En
• Other Authors: Wong Yiik Diew
• Format: Thesis-Master by Research
• Language: English
• Published: Nanyang Technological University 2020
• Subjects: Engineering::Civil engineering::Transportation
• Online Access: https://hdl.handle.net/10356/136848
• Institution: Nanyang Technological University

This project involves the development of a simple motorcycle simulator which, together with an eye tracking device, was then used to study the response times (RTs) and eye gaze patterns of motorcycle riders. The simulator was built by integrating a scrap motorcycle frame with the necessary controls (steer, throttle, brake) and a virtual reality program to render the 3D environment and customised hazard scenarios. The data records of the eye tracking device combined with the recording of the responses of participants on the simulator is a safe and objective way to study the response behaviour of motorcycle riders in the context of their RTs. Test subjects of motorcycle riders were presented with hazards in two modes: hazards that appeared abruptly from behind some visual occlusion (abrupt-onset), and with hazards that appeared gradually (gradual-onset), having been in the field of view of the motorcycle riders for some time before transitioning into a hazard. The hazards occurred in two environments, at the junction and at the link. The hazards entailed right-of-way violation on the part of the other vehicle conflicting with the path of the motorcycle rider. Overall, 88 participants were recruited for this study. In order to control for and examine the effects of experience, three groups of participants were recruited – namely experienced riders, novice riders and unlicensed subjects (not holding a motor-vehicle licence). From the findings of the study, the unlicensed group of participants consistently underperformed relative to the licensed riders (experienced and novice riders). Performance measures included the manner and celerity of accelerator response, their eye gaze behaviour, and their RTs in response to the hazard scenarios. On the other hand, between the two licensed groups, the experienced and novice riders generally performed similarly in terms of their response patterns, propensity of already looking at the hazard area at hazard onset, and the overall RTs. In comparing scenario types, junction scenarios appeared to provoke more anticipatory eye gaze behaviour than link scenarios, consistent with a more top- down cognitive approach in hazard perception when faced with a higher conflict zone. This study also found that gradual-onset hazards resulted in longer overall RTs than abrupt-onset hazards, mainly contributed by the initial time-to-first-fixation sub-component of the RT for gradual-onset hazards, rather than the remaining fixation to response sub-component. The performance advantage to riders responding to abrupt-onset hazards may be attributed to the attention-capturing nature of the sudden appearance of an object in the visual field, but other reasons such as a narrower search field cannot be ruled out.