Measuring the Motion of Vulnerable Road Users Relative to Moving HGVs

This paper focuses on measuring the motion of a cyclist moving adjacent to a heavy goods vehicle (HGV), from the detections of ultrasonic sensors installed along the side of the vehicle. The measurements are used in a prototype collision avoidance system that predicts the future relative motion and assesses the likelihood of a collision. An array of ultrasonic sensors is adopted to cover the near side of the HGV, where most of fatal collisions with cyclists occur. A method combining quadratic programming and Kalman filtering is developed in this paper for recovering the bearing angles of the cyclist from the detected distances provided by off-the-shelf ultrasonic sensors. The algorithms are developed for use in real time and practical constraints are considered. The simulation and testing results prove the effectiveness of the proposed method for a reasonable range of the speed differential between the cyclist and the HGV.