A COMPUTER-SIMULATION ENVIRONMENT FOR THE TRAJECTORY PLANNING OF COMPLEX ROBOTIC SYSTEMS

This paper presents a trajectory-planning scheme and a simulation envi ronment, for redundant manipulators with a treelike topology. The meth od is based on Liegeois' local trajectory-planning algorithm and combi nes obstacle avoidance and joint limit constraints. An underdetermined linear system of equations is first obtained from the velocity equati ons. Then, the singular value decomposition is used and a weighted min imum norm solution of the system is computed A correction to this solu tion is then generated as two joint velocity vectors lying in the null space of the Jacobian matrix and which are added to the minimum norm s olution in order to avoid the obstacles and the joint limits. A simula tor of mt complex 24-dof system is finally introduced and described Th e simulation environment can he used for the development of automatic trajectory planning or shared trajectory-planning strategies as well a s for the training of operators. Examples of results obtained with the simulator are given.