Trajectory planning for mobile manipulators including Manipulability Percentage Index

This article addresses the problem of the achievement of Operational Point to Point Tasks by mobile manipulators (MMs). An operational target point (tp) is the objective to be reached by the end-effector of a manipulator mounted on a wheeled mobile robot. The assigned task is realizable from many ways. Several potential feasible trajectories can be generated and several final postures of the robot can be selected to reach the tp. Dealing with the presented problem means finding the best way to reach tp. New singularity avoidance metric named Manipulability Percentage Index (MPI) is introduced in this article in order to place the mobile robot on areas guaranteeing regular reachability. The MPI is included in a trajectory planning process for reaching tp. The compromise between the minimum time for performing the task and the value of the MPI index is discussed.