Comparison of unconstrained and constrained calibration methods.

Abstract

The idea of using a passive end point motion constraint to calibrate robot manipulators is of particular interest because no measurement equipment is required. The accuracy attained using this method is compared to the accuracy attained by an unconstrained calibration using computer simulated measurements. A kinematic model is established for each configuration using the Denavit- Hartenberg methodology. The kinematic equations are formulated and are used in the computer simulated calibration to determine the actual kinematic parameters of the manipulator. The results are discussed in terms of the effect of measurement noise and the number of experimental observations on the accuracy of parameter identification. Robot calibration