平行式工具機精度校驗分析與CNC工具機之體積誤差與輪廓誤差電腦輔助檢測系統之研發

Study of Calibration for Stewart Platform based Machines and Development of Computer-Aided Measurement System for Volumetric Error and Contouring Error for CNC Machine tools

黃駿達(Chun-Ta Huang)

指導教授 ： 王世明

中原大學/工學院/機械工程研究所/碩士(2005年)

https://doi.org/10.6840/cycu200500647

摘要

中文摘要
為了能提升CNC工具機之精密度，量測出誤差值是必要之步驟，藉由找出誤差值，在加工時修正與補償，以改善加工之精密度。本研究的主要研究內容包括兩大項（1）史都華六軸平台（Stewart Platform based Machines）Ball Joint位置誤差（Location Errors of Ball Joints）的校驗方法。（2）發展精密工具機之體積誤差與輪廓誤差的電腦輔助檢測系統。史都華六軸工具機（Stewart Platform）因為其結構關係，在製造與組裝過程中會造成Ball Joint的位置誤差，Ball Joint位置誤差會影響整個平台整體的伺服精度。由於史都華六軸平台是採用逆向運動方程式驅動，必須知道Ball Joint精確位置才可正確的驅動平台。可結合量測與數值方法求得Ball Joint的正確位置，本研究量測方法以單點法量測位置誤差，再配合兩階段式角度誤差量測量測出平台總體積誤差作為已知條件，再採用牛頓疊代法（Newton-Raphson Method）進行數值計算，以得到Ball Joint的正確位置誤差，進而回饋至逆向運動方程式以正確的驅動平台。研究之另一部份為發展CNC多軸工具機的體積誤差與輪廓誤差電腦輔助量測系統，其係將多軸工具機之總體積誤差（Volumetric Error）及輪廓誤差量測方法與誤差預測與補償方法整合成一系統，除可供作工具機多元精度校驗外，更可進一步用以再提升工具機的加工精度。

關鍵字

Ball Joint誤差 ； 牛頓疊代法 ； 誤差補償 ； 史都華六軸平台 ； 體積誤差 ； 輪廓誤差

並列摘要

ABSTRACT
In order to improve the accuracy of CNC tool machine, error determination is important and necessary for calibration, driving, and compensation. Main research work dedicated in this study was to develop: (1) the method to determine the location errors of a 6-DOF Stewart platform based machine, (2)a computer-aided volumetric/contouring error measurement system for CNC multi-axis machines. Because of the characteristics of structure and the driving method, location errors of Stewart platform must be known. By integrating the 2-step volumetric error measurement method and Newton-Raphson numerical method, the location errors of ball joints of Stewart platform based Machines can be determined for the inverse kinematic model to accurately drive the machine. The other part of this research was to develop a computer integrating system that can directly measure the volumetric errors and contouring errors of a multi-axis machine. The system can directly inspect the total errors of a machine, such as total positional errors, total orientation errors, and contouring errors. It provides a fast and systematic way to determine the final accuracy of a CNC machine. In addition, the system can be integrated with the developed error prediction compensation system to further improve the machining accuracy of a CNC machine.

並列關鍵字

Stewart Platform based Machines ； Volumetric Error ； Error Compensation ； Contouring Error ； Newton-Raphson Method ； Location Errors of Ball Joints

參考文獻

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