Mechanical Engineering Journal (Jan 2017)
The autonomous frontal obstacle avoidance system with trajectory updating function
Abstract
Recently, in order to decrease the number of traffic accident, various automotive safety technologies have been studied. As one of those technologies, the authors have proposed the autonomous frontal obstacle avoidance system, which recognizes a frontal obstacle such as a pedestrian, predicts the location of collision based on the obstacle's motion and avoids collision by autonomous evasive steering. The proposed system calculates avoidance trajectory once at the start of avoidance. Therefore, it cannot handle the situation that the obstacle's motion changes. Especially in the case that the obstacle accelerates after its appearance, the system will cause a collision with the obstacle. Since pedestrians' motion in the real world is not always constant, change of motion of the obstacle must be considered. Therefore, in this paper, the authors improve the system so that it can handle those situations by adding an updating function of avoidance trajectory. This paper first describe the derivation of avoidance trajectory from the vehicle state in evasive motion. Next, the autonomous frontal obstacle system is redesigned by building peripheral functions such as collision forecasting functions and appropriate trajectory selection function and integrating them. The redesigned system is examined by numerical simulations and compared with the previously proposed systems to verify the validity and effectiveness. The results indicate that the system proposed in this paper is valid and more effective than the previously proposed system.
Keywords