Higher order approximation of the generalized kinematic error compensation model for robots

Abstract

This article presents a higher-order approximation of the “generalized” kinematic error compensation model to enhance position accuracy and repeatability of robotic manipulators. The “generalized” model originally proposed by Driels and Pathre is successfully extended to include non-linear coupling effects among all error parameters. A pertubration technique is used in which second-order error terms are retained for improvement to the Denavit-Hartenberg A and T matrices. The model is called “generalized” in a sense that it incorporates ten error parameters (all six possible errors and four link parameter errors) per manipulator's joint axis. The second-order terms in the model become important when considering large robot structure size or when input kinematic errors increase in their magnitudes. The formulation of the generalized Jacobian matrix is also presented including second-order error terms in the analysis.