On the Effect of the End-effector Point Trajectory on the Joint Jerk of the Redundant Manipulators

Abstract. This paper is focused on investigating the joints jerk of industrial serial redundant manipulators with 6 degrees of freedom (6-DOF) under the variation of the end-effector point (EEP) trajectory in the workspace. The EEP trajectories are initially built in the basic planes because of their simplicity, verification and experimentation are smooth, and most of the actual welded structures are performed on these basic planes. The jerk is determined by solving the inverse kinematics problem of the redundant system. This problem is solved based on the algorithm which is used for adjusting the increments of the generalized coordinate vector (AGV). The efficiency of this algorithm is shown through the error between a given trajectory and the recalculated trajectory through the forward kinematics problem. The result of this study allows us to evaluate the effect of the change of the trajectory on the kinematics characteristics of the robot in general and the jerk of the joints in particular. On the other hand, these results can be used as the basis for planning the EEP trajectory for redundant robots, developing algorithms to reduce joint jerky, increase the life of robot systems, and improve the accuracy of the redundant robot movement. © 2021 Published by Shahid Chamran University of Ahvaz