基于均匀磁场标定的微动力测试平台研究

Research on micro-thruster test platform based on uniform magnetic field calibration

针对微纳卫星的微动力测量问题,设计了一种可对mN级微动力进行测试与分析的扭摆型微动力测试平台;基于电磁力法,采用通电导线和电磁铁组合的方式设计了该测试平台的关键装置--微小标定力产生装置。利用高精度电子天平和激光位移传感器对微动力测试平台进行了静态标定,并通过对导线在磁场中不同位置进行标定实验,得到重复性误差为0.264%,验证了均匀磁场标定的可行性;采用阶跃响应法对测试平台的系统参数进行了标定,最后对微动力测试平台的不确定度和标定方法带来的误差进行了分析。结果表明,该测试平台的测量范围为1~400 mN,分辨率约为1 mN,静态标定的不确定度为8.41 mN,标定方法误差为0.84%,误差较小,能为微动力测量提供一定的技术参考。

Aiming at the problem of micro-thruster measurement of micro-nano satellite,a torsional pendulum micro-thruster test platform with mN-level micro-thrust test and analysis function was designed.Based on the electromagnetic force method,the key device of the test platform,the micro calibration force generating device,was designed by combining electrified wire and electromagnet.The static calibration of the micro-thruster test platform was carried out by using a high-precision electronic balance and a laser displacement sensor.And through the calibration experiment of different positions of the wire in the magnetic field,the repeatability error was determined to be 0.264%,which verify the feasibility of the uniform magnetic field calibration.The system parameters of the test platform were calibrated by using the step response method.And finally,the uncertainty and error brought by the calibration method were analyzed.The results show that the measurement range of the test platform is 1~400 mN,the resolution is about 1 mN,the uncertainty of static calibration is 8.41 mN,and the error of calibration method is 0.84%,which is relatively small.The micro-thruster test platform can provide a certain technical reference for micro-thruster measurement.