正弦加速度激励下石英加速度计的标定方法

Calibration method of quartz accelerometer under sine acceleration

为更充分激励加速度计误差模型中高阶项误差系数,提出了采用盘式离心机进行动态加速度激励的试验方法。首先,通过分析离心机误差源,建立了离心机主轴正弦角速度、离心机位姿误差、加速度计安装误差与加速度计精确比力输入之间的内在联系,同时建立了包含了工具误差的加速度计的完整误差模型。其次,提出了误差模型辨识的三姿态试验方法,并通过最小二乘法完成对加速度误差模型误差系数和测试设备仪表误差的辨识。所提出的三姿态试验法相对于传统的十姿态试验法显著提高了标定效率。仿真试验结果表明,在高阶参数的辨识中消除了离心机工具误差和加速度计的安装误差对加速度计误差模型标定精度的影响,误差模型系数辨识的精度可控制在模型系数的5%以内。

In order to more fully excite error coefficients of higher-order terms in the accelerometer error model,a test method using a precision centrifuge to generate a dynamic acceleration excitation is proposed.Firstly,by analyzing the error source of the centrifuge,the intrinsic relationship between the sinusoidal angular velocity of the centrifuge spindle,the attitude error of the centrifuge,the installation error of the accelerometer and the precise specific force input of the accelerometer are established.Meanwhile,the complete error model of accelerometer including tool errors of the centrifuge is established.Secondly,a three-position test method for error model identification is proposed,and the error coefficients of acceleration error model and instrument error of test equipment are identified by the least square method.Compared with traditional calibration methods,the calibration efficiency is greatly enhanced by reducing the installing positions of the accelerometer from ten to three.The simulation results show that the influence of centrifuge tool error and accelerometer installation error on the calibration accuracy of the accelerometer error model is eliminated in the identification of higher-order parameters,and the identification accuracy of the error model coefficient can be controlled within 5%.