基于激光干涉比长的大范围线位移动态校准系统研究

Research on dynamic calibration system of large range linear displacement based on laser interference comparator

为解决大范围、高精度的线位移传感器连续自动校准问题,在用于校准高精度线纹尺的激光干涉比长仪标准装置上研制线位移传感器动态校准系统。采用基于环境参量测量的激光波长实时补偿的激光干涉仪作为标准位移发生器,实现位移传感器示值误差校准的高精度直接溯源;设计基于标准激光干涉仪细分脉冲的同步触发系统,实现在运动过程中对标准干涉仪信号和被测位移传感器输出信号的同步实时采集。对校准系统进行测量不确定度评定及利用多种位移传感器进行试验验证,结果表明本系统实现动态位移自动校准,测量范围可达1m,测量不确定度0.02μm+1.0×10^(-6)L(k=2)。

In order to solve the problem of continuous automatic calibration of linear displacement sensor with large range and high precision,a dynamic calibration system of linear displacement sensor is developed on the standard device of laser interferometer for the calibration of high-precision linear scale.The laser interferometer with the real-time compensation of laser wavelength based on the measurement of environmental parameters is used as the standard displacement generator to realize the high-precision direct tracing of the error calibration of the displacement sensor.The synchronous triggering system based on the subdivided pulse of the standard laser interferometer is designed,and the synchronous real-time acquisition of the standard interferometer signal and the output signal of the measured displacement sensor is realized during the motion process.The measurement uncertainty of the calibration system is evaluated,and various displacement sensors were used for test verification.The results show that the system realized automatic dynamic displacement calibration,its measures range up to 1000 mm,its measurement accuracy isρ=0.02μm+1.0×10^(-6)L(k=2).