基于无陀螺微惯性测量单元的惯性恒星罗盘

为满足微纳航天器对姿态确定系统的体积、重量、功耗、精度等严格要求,提出用无陀螺微惯性测量单元(GFMIMU,Gyroscope-Free Micro Inertial Measurement Unit)和星敏感器组成惯性恒星罗盘(ISC,Inertial Stellar Compass)的姿态确定方案.根据无陀螺的测量原理建立了ISC的状态方程,将星敏感器的姿态测量信息作为观测量,修正GFMIMU长时间工作误差的积累.利用卡尔曼滤波器对ISC的定姿误差进行估计,并采用可观测性分析理论证明滤波器的滤波稳定性.最后,对ISC进行了系统仿真,仿真结果证明ISC可以满足微纳航天器的使用要求. 

Novel inertial stellar compass based on gyroscope-free micro inertial measurement unit

Micro/nano spacecrafts need an attitude determination system performance in high accuracy,compact size,small mass and low power consumption.A novel inertial stellar compass(ISC) was designed to meet these requirements,which based on the gyroscope-free micro inertial measurement unit(GFMIMU) and integrated a star camera.The theory about how GFMIMU works to measure attitude angle was established.The state equation for ISC was modeled based on such theory,and the estimation equation was built up using measure information of the star camera.A Kalman filter approach was constructed to compensate the GFMIMU error in long-term working conditions,and the stability of the filter was proved using the observability analysis theory.A simulation of ISC was introduced finally,and the simulation results verify the proposed ISC can be used in micro/nano spacecrafts.