加速度计组件冷启动温度模型参数的标定方法

Calibration of temperature model parameters for accelerometer triad during after-power-on process

为补偿激光陀螺捷联惯性系统冷启动过程中的加速度计组件测量误差,建立加速度计组件温度参数的二阶多项式回归模型。为提高温度参数模型的环境温度适应性,提出了一种自然升温环境下,基于不带温箱的三轴转台的加速度计组件连续多次标定方法,借助于激光陀螺的辅助测量,通过构建36状态无系统噪声的特殊卡尔曼滤波器,无需测量噪声的先验信息,以递推方式可有效估计出温度模型参数的各项系数,同时解决了温度模型参数的传统辨识方法过于依赖温箱的问题,并有效缩短了标定时间。实验结果表明,与不进行温度参数补偿的结果相比较,基于温度参数二阶多项式回归模型的补偿方法,3h重力值测量误差均值减小至7.05%,测量误差标准差减小至3.97%,相应的3 h导航定位误差由3897.85 m减小至3508.79 m,从而较好地补偿了加速度计组件在系统冷启动过程中的热漂移误差,实现了系统冷启动后的快速正常工作。

A second-order polynomial regressive model of temperature parameters in the accelerometer triad is established in order to reduce the measure error of the accelerometers during the after-power-on process of the SINS.Considering the better adaptability for the real ambient temperature of the proposed model,a multi-calibration method of the accelerometer triad,based on the three-axis turntable without any incubator,is put forward in the real rising temperature environment.With the aided measurement of the laser gyroscope,a 36-state special Kalman filter is utilized,where the procedure noise is set to be zero,but the unknown measurement noise exists.Then the temperature model parameters can be estimated efficiently by the recursion relation without the prior distribution of the measurement noise.Meanwhile,the severe time-consuming problem can be avoided during the traditional calibration method,which has to make use of the incubator.The test results illustrate that,the three-hour mean value of the residual gravity is reduced to and the standard deviation is reduced to with the temperature compensation of the model parameters,comparing to the case where no temperature factor about model parameters is taken into account.After the temperature compensation,the corresponding orientation error is,from m,decreased to m during the static navigation process.According to the above facts,the measurement error of the accelerometer triad,brought by the thermal drift,is successfully cut down.So the requirement that the SINS effectively operate without warming-up stage has been achieved.