传感器调零误差对直线误差分离的影响规律及其确定方法分析

分析了多点法直线 EST中传感器初始调零误差对直线误差分离结果的影响 ,指出不同方法的影响规律不同 :时域三点法中调零误差使直线形状误差按抛物线规律呈非线性增大 ,对直线误差评定产生很大影响 ;时域二点法中调零误差使直线形状误差线性增大 ,但对评定无影响 ;频域三点法的直线误差则不受调零误差的影响。提出了通过构造软基准来确定调零误差的两种方法 :时域频域结合法和对称反转配置法 ,可以克服常规方法的局限性

Study of the Influence of Zero Error of Probes on Straightness Error Separation

The zero error of probes has an important effect on the separating results of straightness error. The influences are different for various methods of straightness error separation. For time domain three point method, straightness error accumulates nonlinearly complying with the parabolic curve, and its evaluation is greatly affected by zero error. For time domain two point method, straightness error accumulates linearly, but its evaluation will not be affected. For frequency domain three point method, straightness error will also not be affected by zero error. We present the following two methods: (1) the method combining time domain and frequency domain; (2) the method of symmetrical and reversal arrangement. These methods can be used to obtain the zero error by means of constructing software datum and overcome the limit of conventional method.