Optimal motion planning of robotic manipulators removing mobile objects grasped in motion

The following study deals with motion optimization of robot arms having to transfer mobile objects grasped when moving. This approach is aimed at perf orming repetitive transfer tasks at a rapid rate without interrupting the d ynamics of both the manipulator and the moving object. The junction locatio n of the robot gripper with the object, together with grasp conditions, are partly defined by a set of local constraints. Thus, optimizing the robot m otion in the approach phase of the transfer task leads to the statement of an optimal junction problem between the robot and the moving object. This o ptimal control problem is characterized by constrained final state and unkn own traveling time. In such a case, Pontryagin's maximum principle is a pow erful mathematical tool for solving this optimization problem. Three simula ted results of removing a mobile object on a conveyor belt are presented; t he object is grasped in motion by a planar three-link manipulator.