幾何誤差對工具機而言,是評估性能的關鍵指標之一。要提高工具機加工精度,則須要量測機器誤差並改善。本論文引用徐永源教授之建模方法建立五軸幾何誤差模型,該模型包括了43項幾何誤差,用以預測關鍵性的誤差項。並提出角度補償技術。 目前業界對於體積誤差補償方法為針對定位、直線度與垂直度做補償,而偏擺所造成的誤差卻沒有補償。實驗中發現偏擺角度(pitch、roll、yaw)對體積誤差有極大影響,故本論文針對Y軸搖擺角度做量測,可得知X方向之水平直度與Y方向定位的偏差量,進而開發出角度補償程式,該程式能規劃出補償Y軸行走範圍內,由yaw角度影響的偏移誤差路徑碼。 本論文由量測結果推算補償關係式,成功發展一個路徑補償程式,以路徑補償的方式進行補償,達到快速補償的效果,可將誤差補償至±2 μm內。
The geometric errors is one of the key indicators to define performance of machine tools. In order to improve the precision, the error of the machine tools should be measured and improved. In this accuracy, the geometric error model of the five-axis machine tool, using homogeneous transformation matrix has been proposed. The model based on the ISO standard is composed of 43 geometric errors. In this paper. The correctness of the proposed geometric model was carried out by the laser interferometer. According to the ISO standard, the three rotational and three translational errors of a single-axis case error in position on a workpiece. In position and horizontal straightness error measurement process, the measurement results will be effected by modifying the angle parameters in different position. For example, the YAW angle error of Y-axis will effect the straightness of X-direction and positioning of Y-direction. In this thesis, a path compensation program based on calculating formula has been proposed. The error can be compensated less than ±2 μm quickly.