error of datum displacement 基准位移误差
Surface should be used as a fine datum to be processed first, because the precision of the positioning of the surface is more accurate, the smaller the clamping error is.
用作精基准的表面应先加工出来，因为定位其准的表面越精确，装夹误差就越小。
The micro Angle error between optical coordinate and mechanical datum coordinate of robot vision instrument due to mechanical assembly can be corrected by high accuracy calibration.
机器人视觉仪器由于机械安装引起的光学坐标系与机械基准坐标系之间的微小的角度误差可以通过高精度标定修正。
Accoding to the concept, datum contained careless error are rejected, data management is simplified and measure of precision of measurement result is raised.
利用这一概念，可剔除含粗大误差的数据，从而简化数据处理，提高测量结果的精确度。
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