航天器转动惯量和惯性积的集成一体化测试方法

Research on Integration Testing Method on Rotational Inertia and Product of Inertia for Spacecraft

通过测量扭摆台的扭摆周期测试卫星的惯量张量,测试在不同安装角度下的惯性矩计算转动惯量和惯性积,用矩阵变换原理计算惯性在主轴的大小、方向和纵横惯量比。分析发现影响转动惯量测量精度的主要因素是摆动周期测量误差,以及试验方法和测量工装产生的误差。采用空载摆动周期尽量长(大于1s)、多次测量(6次以上)的平均值并用最小二乘法对数据进行处理,以提高转动惯量和惯性积的测量精度。给出了某卫星质量特性的测试过程,用扭摆法测得其转动惯量、惯性积和纵横惯量比,测试结果均满足指标要求。该法还适于大型弹箭和空间飞行器的转动惯量和惯性积测试。

The inertia tensor of a satellite is tested by measuring the oscillatory period of torsion pendulum table. The rotational inertia and product of inertia are tested using the measured values of the moment of inertia at different installation angles. Based on the principle of matrix transformation, the size and direction of inertia in principal axis and inertia ratio of vertical to horizontal are calculated. Through analysis, it is found that the main factors affecting the testing accuracy of rotational inertia are the measurement error of oscillatory period and the error caused by testing methods and measuring tooling. In order to improve the testing accuracy, the measures have been taken, including prolonging the oscillatory period as long as possible（longer than 1 s）, using mean value of multi-testing（more than 6 times） and using the least square method to process testing data. The test procedure of some satellite was given. The testing results of rotational inertia, product of inertia and the inertia ratio of vertical to horizontal were obtained, which all met the index requirements. The method proposed in this paper is also suitable for the test of rotational inertia and product of inertia for large missiles and rockets, as well as three-axis stabilized satellites.