Practical high curvature path planning algorithm in joint space

Abstract

A practical high curvature path planning algorithm that considers the velocity limit of a mobile robot in joint space is proposed. The existence of obstacles that constrict the smooth movement of mobile robots is inevitable. To avoid incoming collision, the robot is redirected to a new path with respect to the dimensions of the obstacle and a safety factor. The redirected path consists of geometric constraints such as high curvatures on its turning points which cause difficulty in controlling the mobile robot. Thus, a central velocity generation method that considers both velocity limits through a convolution operator and high curvatures at turning points is suggested. The central velocity is able to be within the configured velocity limit, otherwise actual velocity commands in joint space could result. Therefore, interpolation to obtain uniform sampling and velocity downscaling is performed to generate a feasible joint space trajectory. The result shows short travelling time compared with previous methods while satisfying velocity limits in the joint space.