Identification of and compensation for backlash on the contouring accuracy of CNC machining centres

The paper describes a technique for the identification of and compensation for backlash on the contouring accuracy of computer numerically controlled (CNC) machining centres. A circular rest that has been developed for rapidly checking the contouring accuracy of CNC machine tools is used to measure the contouring error due to backlash. Backlash error on the contouring profile is found as the direction of motion is reversed. A compensation strategy based on a simulated annealing (SA) optimisation algorithm is then developed to reduce the backlash error. Computational simulations and experimental rests have shown that the contouring error dire to backlash can be greatly reduced by using this new approach.