Local Smooth Path Planning for Turning Around in Narrow Environment

In this paper, we introduce a local smooth path planning algorithm for turning around in narrow environment. The algorithm uses a combination of the minimum turning radius arc and the Bezier curve to generate a near optimal smoothing turn-around path in narrow roads or cluttered environments. The algorithm will generate a smooth trajectory that conforms to the kinematic constraints of unmanned ground vehicle (UGV), by adjusting the heading to the target angle through several minimum-radius turns, and smoothly connecting to the global reference path via Bezier curve. We analyze the surrounding congestion and narrowness to choose appropriate turn-around area by integrating obstacle distribution and road edges before path planning. The algorithm was tested at IN2BOT UGV in our campus and 2018 Cross Dangers & obstacles. The experimental results indicated that the algorithm works efficiently with our previous work and shows good performance in accuracy and computational time.