Optimal trajectory planning of robot manipulators in the presence of moving obstacles

A method for computing the optimal motions of robot manipulators in the pre sence of moving obstacles is presented. The algorithm considers the nonline ar manipulator dynamics, actuator constraints, joint limits and obstacle av oidance. The optimal traveling time and the minimum mechanical energy of th e actuators are considered together to build a multicriterion function. Seq uential unconstrained minimization techniques have been used for the optimi zation. Given the initial and final points the trajectories are defined usi ng spline functions and are obtained through off-line computation for on-li ne operation. The obstacles are considered as objects sharing the same work space performed by the robot. The obstacle avoidance is expressed in terms of the distances between potentially colliding parts and the motion is repr esented using translation and rotational matrices. Numerical applications i nvolving a Stanford manipulator are presented. (C) 2000 Elsevier Science Lt d. All rights reserved.