工具機阿貝誤差補償器的研究

Development of an Abbe error compensator for NC machine tools

王綜漢(Tsung-Han Wang)

指導教授 ： 范光照

國立臺灣大學/工學院/機械工程學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.03243

摘要

數控工具機的位置回授是採用位移感測器(光學尺或編碼器)，但是位移感測器的量測軸線無法和切削點的運動軸線同軸，因此角度誤差造成的阿貝誤差，是工具機的體積誤差主要來源。
本研究利用角度干涉儀偵測運動平台的俯仰度、偏搖度。另外，利用兩個四象限感測器配合角藕稜鏡，製作可量測兩維直線度及滾動度誤差之感測器，上述可整合成一套同時量測三角度誤差(pitch、yaw、roll)和二個直線度(horizontal、vertical)之五自由度量測系統。
本研究以立式三軸工具機為對象，依此結構配置、位置回授方式(光學尺、編碼器)、阿貝誤差，推導體積誤差公式。此外針對發那科、PC-based控制器發展阿貝誤差補償器，透過原點漂移的方式補償阿貝誤差。
實驗結果可知，以光學尺作位置回授，其定位誤差主要是阿貝誤差造成，然而編碼器回授方式，其定位誤差除了阿貝誤差影響外，還須考慮線性誤差。在這些的考量下，工具機的精度應可大幅改善。

關鍵字

阿貝誤差 ； 體積誤差 ； 三角度感測器 ； 五自由度量測系統 ； 阿貝誤差補償器

並列摘要

The displacement sensor (optical scale/encoder) is used as the position feedback for NC machine tool. However, all displacement sensors are never in line with the cutter point. Therefore, the accuracy of NC machine tool is mainly caused by angular errors of motion due to the well-known Abbe principle.
In the measurement system, the angle interferometer is developed for the detection of pitch、yaw angular errors. Moreover, a sensor that can measure roll angular error and 2D straightness is fabricated by use of laser source, optical component and two quadrant detectors. Finally, the angle interferometer and the roll sensor are integrated into 5DOF measurement system, which can measure pitch、yaw、roll angular errors and 2D straightness simultaneously.
Based on the 3axis vertical machining center and position feedback type (light scale or rotary encoder), the volumetric error for Abbe error is derived. In addition, the Abbe compensator for FANUC and PC-based controller is also developed.
For light scale position feedback, experiments show that the positioning error is majorly affected by Abbe error. For encoder position feedback, the accuracy is influenced not only by Abbe error but also by ball screw pitch error. Finally, the accuracy of NC machine tool must have a great improvement.

並列關鍵字

Abbe error ； volumetric error ； three angle sensor ； 5 DOF measuring system ； Abbe error compensator

參考文獻

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