介绍了新研制的四点法误差分离技术（ＥＳＴ），用来分离工件的形状误差和工作台的误差运动：三个传感器Ａ，Ｂ和Ｃ作ｌ１＝ｌ２＝ｌ的等间距布置，第四个传感器Ｄ与Ｃ的间距为ｌ±ＴＳ，而ＴＳ为采样间隔。只要预置合适的初值并经适当的计算路线，便可重构出工件形状误差和工作台的运动误差。本方法区别于频域三点法的特点是毋需进行ＦＦＴ运算，而区别于时域三点法，则是采样间隔又不受传感器间距的制约。 Introduced the newly developed four-point error separation technology (EST), used to separate the workpiece shape error and table error movement: three sensors A, B and C for l1 = l2 = l equidistant arrangement, the fourth The distance between sensors D and C is l ± TS, and TS is the sampling interval. As long as the proper initial value is preset and the route is calculated properly, the shape error of the workpiece and the movement error of the worktable can be reconstructed. This method is different from the frequency domain three-point method is characterized by the need for FFT computing, but different from the time domain three-point method, the sampling interval is not subject to sensor spacing constraints.