空间稳定系统加速度计在线标校

摘要

三轴加速度计是惯性导航系统的核心元件之一,其误差对导航精度具有重要影响.提出一种适用于空间稳定系统的加速度计在线标校方法.在三轴加速度计十二系数误差模型基础上,推导比力的模误差与加速度计误差系数之间的关系式.设计一个五维静态Kalman滤波器进行加速度计组合误差系数的在线标定,并讨论了加速度计组合误差的补偿方法.计算机仿真和多组试验结果表明:采用所提方法,空间稳定系统加速度计误差的标校精度达到1×10-5g量级,所用加速度计的长期稳定性优于1.5×10-5g,对实现高精度导航具有实用价值.%Tri-axial accelerometers are one of the key components in inertial navigation systems(INS), whose errors impose important effects on navigation precision. A method of online calibrating and compensating accelerometers is presented for space-stable INS. Based on the twelve-coefficient model of tri-axial accelerometers, the norm error of specific force is derived. A static Kalman filter of five dimensions is designed to calibrate the synthesized error coefficients of accelerometers, and a method of compensating accelerometer synthesized errors is discussed. Results of computer simulations and multi-group experiments show that, with the presented method, the calibration and compensation precision of accelerometer can reach 1×10-5 g for space-stable systems, and the long-term stability of the used accelerometers is better than 1.5× 10-5 g, which are of practical value in realizing high precision navigation.