Motion Planning for Mobile Manipulators Based on an Improved A Algorithm and Manipulability

To address the problems of long planning time and poor operability of pick-and-place (PAP) movement of a mobile manipulator in an indoor environment, an enhanced regular A* algorithm was proposed to determine the optimal docking position and perform system motion planning, using manipulator operability as the evaluation criterion. Firstly, on the basis of conventional A* algorithm, eight search directions were simplified to five to improve the search efficiency. At the same time, a new heuristic search function was designed, and Floyd algorithm was introduced into the A* algorithm to increase the smoothness of the path. The simulation results show that the running time of the improved A* algorithm is shortened by 59.1%, the path length was reduced by 3.5%, and the number of search nodes is reduced by 41.6%. Secondly, according to the reachable workspace and Jacobian matrix of the manipulator, the maneuverability of the mobile manipulator in different positions near the target object to be PAP was evaluated, a