Configuration-based compliance control of kinematically redundant robot arm Part II: Experimental validation

Abstract

This two-part paper presents an approach to the control of robot endpoint compliance, i.e., elasto-mechanical interaction between a robot and its environment using kinematic redundancy instead of actuation redundancy. In Part I this approach is developed by proposing the Configuration-based Stiffness Control (CSC) method for kinetostatically consistent control of robot compliant behaviour, based on the gradient projection of the cost function which minimizes the norm of off-diagonal elements of the jointspace matrix. In Part II validity of the proposed compliance control method is tested by simulation experiments using as a simulation platform two specific cases of most simple kinematically redundant robot arms: Case 1 - experiments with onedimensional taskspace (m=1) and minimal possible redundancy, r = (n - m) = 1, and Case 2 - experiments with onedimensional taskspace (m=1) and minimal possible hyper-redundancy, r = 2 and r > m. In both cases the singularity and joint limits were not considered.

Keywords

• kinematic redundancy
• compliance control
• nullspace