Offset-Based Path Planner for Lane Keeping of Autonomous Bus

Compared to passenger cars, buses have longer lengths and wheel-bases. Therefore, additional planning techniques are required to keep all the edges of the bus within the lane boundary. In this paper, we propose an offset-based planner which calculate drivable-offset from the center line. The proposed planner can be divided into three stages. First, road curvature for the lane is approximated using Bezier curve method. Then, the outer and inner offsets for each lane point is derived from the curvature and vehicle’s parameters. Finally, a new reference path is created based on the selected offsets. The proposed method is verified under actual driving conditions, including left and right turns.