Redundancy Control With Position Prior Orientation Of Serial Manipulators Using The Concept Of Task Priority

Abstract

In this thesis work, the redundancy resolution of serial robot manipulators is performed. Redundant manipulators have the characteristics that there exists infinite solutions to the inverse kinematic problem. Out of those infinite solutions, it is possible to choose certain specific solutions on merit, which can be selected on the basis of some performance criteria or priority of some tasks over the other. These priority subtasks can be position prior to orientation (PPO), torque minimization, obstacle avoidance, singularity avoidance etc. Out of these parameters, this thesis is focused on position prior to orientation. The concept of task priority is used, which is implemented in relation to the inverse kinematics problem of redundant manipulators. A required task is divided into a number of subtasks according to the order of priority. The redundancy resolution is performed to achieve the required orientation of the end effector while tracing a given trajectory. The entire procedure is formulated using the pseudoinverse of the Jacobian matrix. A number of numerical simulations are performed for different trajectories which includes straight line, rectangular, triangular, circular trajectories to show the efficacy of the redundancy control scheme. Also to show the validity of the formulation, these cases are discussed further by tuning the parameters.