Smooth and collision-free path planning for holonomic mobile robot based RRT-Connect

Abstract

Robot navigation is a crucial aspect of any mobile robot system. Many path planners generate a path that is zigzag in nature and contains many sharp or angular turns. Such courses are not adequate for a mobile robot to follow as it has to slow down and then speed up at these sharp turns. Thus, the integration of the smoothing function is a vital aspect to generate smooth and continuous paths. Moreover, a collision check after path smoothing needs to be accounted for a possible collision with obstacles surrounding. Herein, a path pruning algorithm is utilized to reduce the total path waypoints. Then a piecewise cubic B-spline smoothing function is applied to ensure the path is smooth and continuous. In addition, a post-smoothing collision checking and improvement algorithm based on mid-point insertion for the collide segments is proposed. Experiments and comparisons with the geometric RRT-Connect path planner have shown that the inclusion of a path pruning algorithm, smoothing function and post-smoothing collision check generates better results with reduced path length.