Contouring control of ball screw mechanism using a practical control method

Abstract

This paper presents an improved practical controller for enhancing the contouring motion of a ball screw mechanism. Practically, a high motion control performance and ease of controller design are desired. A continuous motion nominal characteristic trajectory following (CM NCTF) control has been considered to fulfill the desired performance. The NCTF controller comprises of a nominal characteristic trajectory (NCT) and a PI compensator where the controller parameters are easily determined and it is free from exact modeling. In the present paper, the CM NCTF controller has been proposed in order to enhance the continuous motion performance such as tracking and contouring accuracies of the system. In order to justify the advantages, the CM NCTF controller was examined in tracking motion performances using an AC driven X-Y ball screw mechanism. The bandwidth of the CM NCTF controller is larger compared to the PID controller, therefore, it proved that the CM NCTF controller has fast response as compared with the PID controller. The experimental results proved that the CM NCTF controller achieves better contouring motion performances than the PID controller by showing a two times smaller motion error.