應用於非圓形車削之可變刀具進給機構之動態建模與伺服控制

Abstract

本論文主要目的是藉由控制器設計，使得非圓形車削機台具有閉迴路控制，以提升車削精度。文中，首先針對刀具滑台的運動狀態，使用Lagrange方法、Lagrange乘數和虛功法，進行動態建模，再運用達朗貝爾原理(D’Alembert’s principle)推導出動態方程式。在伺服控制上，本文針對滑台自動定位與主軸轉速控制，提出—混合控制法。在滑台定位上，使用雷射位移計作為感測裝置，進行進給量的即時偵測，再由NI Single-Board 9632作為控制平台，並以LabVIEW設計人機介面，以控制進給精度；在主軸轉速控制，本研究直接讀取馬達驅動器的轉速訊號至控制平台，以監控主軸轉速。實驗結果顯示，本文所提出之混合控制比只使用滑台自動定位控制器進行非圓形車削，更能有效地提升成品的精度。In the traditional mechanical factory, the cutting of non-circular workpiece is still mainly achieved by changing the model. However, when cutting other shapes of the workpiece, the model must be redesigned, which will increase the cost. The machine used in this paper has been equipped with servo motor with connecting rod and mechanism, so that when the non-circular workpiece is turned, the model is no longer needed. In this paper, a hybrid controller is designed to make noncircular turning process smoother and more accurate. In dynamic modeling, the Lagrange method along with the Lagrange multiplier and the virtual work principle were applied to device, the equations of motion, then the dynamic equations were simplied using the D’Alembert’s principle. In the hybrid control, a controller for the automatic positioning of the slide table with a laser displacement meter being used for instantaneous detection of the feeding displacement. The NI Single-Board 9632 is used as a control platform with the embedded LabVIEW for human-machine interface design for more accurate feeds. The other controller for the spindle speed directly reads the encoder signal of the motor driver into the control platform to realize the monitoring and control of the spindle speed. From the experimental results, according to the different turning methods, the accuracy of the turning is improved after the correction. Moreover, the proposed hybrid control for turning is better than using the slide table automatic positioning controller based on the accuracy of the finished product. Concludes that the use of the hybrid control, and the calibration is completed first, and the obtained precision of the finished product is better. The research results show the feasibility of the closed loop control proposed in this paper.