Abstract

During naturalistic driving studies on Powered Two-Wheelers (PTW), many data are acquired and it is difficult to analyze them all. Therefore, it seems interesting to focus on incident detection in order to reduce the number of driving sequences to be studied. Furthermore, many studies have been conducted regarding crashes, hence the decision to focus on near-crashes. This work deals with the determination of the most adequate PTW’s dynamics parameters and their thresholds for incidents detection.

More than 60 experimental tests were performed on track (braking, slaloms, avoidance manoeuvres…) and on road with an instrumented motorcycle. Data recorded were speed, accelerations, rotation rates, steering angle, steering torque, lean angle, brake pressure and trajectory. The method consists of observing these parameters in parallel with the feeling of the rider when performing the manoeuvres. For example, the rider was not considering to engage strongly the motorcycle capacities strongly for the slalom at 30km/h, while the avoidance manoeuvre at the same speed was considered as an “emergency manoeuvre”.

Next, criteria and thresholds were determined to highlight the suddenness of a manoeuvre and the urgency of a situation. For longitudinal dynamics, the conditions retained are: Longitudinal Speed greater than 10 km/h and deceleration during braking greater than 6 m/s².

Concerning lateral dynamics, two possible criteria were retained: norm of Rotation Rate vector (Roll+Yaw+Pitch) greater than 80°/s or norm of Rotation Acceleration vector (Roll+Yaw+Pitch) greater than 300°/s².

These criteria were then validated on road trips where the rider ensures that he/she is not confronted with an emergency situation.

This study allows determining the PTW dynamic parameters that make it possible to detect incidents or near-crashes. About 30 vehicles were then instrumented to collect a large amount of data on the use of dynamic capacities. In the future these data collection will make it possible to refine the values of these thresholds.