双轴冗余旋转惯导系统精对准方法

Fine alignment method for biaxial redundant rotating inertial navigation system

冗余旋转惯导系统(RRINS)相比捷联惯导系统可在提高可靠性的同时通过旋转调制技术减小惯性器件常值误差对导航性能的影响。针对该类系统高精度初始对准需求,以正四面体RRINS为例,对其精对准进行研究。建立每3个陀螺仪和3个加速度计组合方式下系统精对准误差模型;设计卡尔曼滤波器及双轴转位方案;将每种组合方式下的精对准结果及陀螺仪和加速度计零偏的均值作为最终估计结果。仿真结果表明,加速度计零偏估计相对误差在0.2%以内,陀螺仪零偏估计相对误差在0.1%以内。精对准实验结果表明,同等时间内,所提方法的精对准误差相比静基座减小75%以上,将实验中估计出的零偏补偿惯性器件测量信息后,导航解算姿态误差减小65%以上,导航性能得到有效提高。仿真和实验结果表明,所提方法可有效提高精对准精度,并可准确估计惯性器件的零偏。

Compared with the strapdown inertial navigation system,the redundant rotating inertial navigation system(RRINS)improves its reliability and reduces the impact of constant error of inertial components on its navigation performance by rotating modulation technology.According to the requirement of high-precision initial alignment of this kind of system,regular tetrahedral RRINS was taken as an example to study its fine alignment.Firstly,the fine alignment error model of combined three gyroscopes and three accelerometers was established.Secondly,the Kalman filter and biaxial transposition scheme were designed.Finally,the fine alignment results of each combination and the mean value of zero bias of the gyroscope and accelerometer were used as the final estimation results.The simulation results show that the relative error of zero bias estimation of the accelerometer is less than 0.2%,and that of the gyroscope is less than 0.1%.The fine alignment experiment results show that the fine alignment error of the proposed method is reduced by more than 75%compared with that of the static base within the same time.The attitude error of the navigation solution is reduced by more than 65%after compensating for the inertial component measurement information with the zero bias estimated in the fine alignment experiment,and the navigation performance is effectively improved.The simulation and experimental results show that the proposed method can effectively improve the fine alignment accuracy and accurately estimate the zero bias of the inertial component.