无陀螺捷联惯导系统中加速度计动态误差分析及补偿

Analysis and Compensation on Dynamic Error of Accelerometer in GFSINS

无陀螺捷联惯导系统中,加速度计直接固定在载体上,所以其动态误差对系统精度有显著影响。首先,建立了加速度计动态误差数学模型,给出了动态误差对于九加速度计系统角速度解算的影响,然后,结合三轴转台模型及测试原理,通过网络结构简单、收敛速度快而不存在局部极小值问题的线性神经网络一次性标定了加速度计所有动态误差系数,最后对动态误差标定及补偿结果进行了仿真。仿真结果表明,标定系数的精度随着三轴转台转速的提高而提高,误差标定并补偿后角速度解算精度得到了明显改善。

In the Gyro Free Strapdown Inertial Navigation System （GFSINS）,the precision of system is obviously affected by the dynamic error of accelerometer because accelerometers are directly fixed in the carrier.Firstly,mathematic model of dynamic error of accelerometer was built,and the effect of dynamic error for angular velocity calculation in a nine-accelerometer configuration system was given.Then,based on the model and test theory of three-axis turntable,all dynamic error coefficients were calibrated at one time by using linear neural network which has simple network structure,rapid convergence speed and no part minimum value.Finally,the calibration and compensation results of dynamic error of accelerometer for GFSINS were simulated.Simulation results show that the calibrating precision of coefficients is improved by increasing angular velocity of three-axis turntable,and the accuracy of angular velocity calculation is effectively improved.