Synchronous and Contouring Control for Multi-Axis Motion System

• Main Authors: Li-Yeh Chen, 陳立業
• Other Authors: 陳金聖
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/etgkcp

博士 === 國立臺北科技大學 === 機電科技研究所 === 100 === In the multi-axis mechanism, all axis are linked with synchronous or series configuration. Hence, the performance index of a multi-axis system is not only to improve the tracking performance of each axis, but also simultaneously consider the synchronous and contouring ability for the multi-axis. In this thesis, two multi-axis synchronous subjects (Chapter 2, 3) and two multi-axis trajectory control algorithms (Chapter 4, 5) are proposed to achieve high speed and high accuracy motion control for multi-axis motion system. After build the model of dual-drive ball screw gantry system, a simple and accurate identification process and algorithm are presented and so does its convergence analysis. For synchronous control of a multi-axis system, a new cross-coupling synchronous controller (CCSC) structure using control scheme with compensation at its reference position command is presented, together with its stability analysis. This research adopts the concept of synchronous error transfer function matrix (SETFM) and the mixed sensitivity problem method to design the CCSC. For multi-axis contouring control, there are two control strategies proposed to improve the contouring error. First, a new cross-coupling position command shaping control (CPCSC) structure using control scheme with compensation at its reference position command is also presented, together with its stability analysis. Although the compensated objects of CPCSC and CCSC are different, the control structure and controller design of CPCSC are similar to CCSC, therefore, all properties of CCSC can be inherited from CPCSC. In contrast, a look-ahead contouring error compensation (LACEC) is presented based on the prediction contouring error. It shapes the position commands of all axis in real-time before the original position commands are fed into the servo loops of the motion system. Finally, the proposed control strategies are all implemented on different motion systems to verify the performance. The experimental results show that our proposed control algorithms can individually improve the synchronous and contouring errors of multi-axis motion systems.