针对无陀螺捷联惯导系统姿态解算随时间不断积累的问题，提出一种磁强计辅助无陀螺捷联惯导的组合方案，利用磁强计测量的地磁信息来修正无陀螺惯导系统的姿态角误差，提高了姿态角的解算精度。推导了磁强计输出和姿态角之间的关系，在此基础上提出了一种姿态优化算法，介绍了算法的基本原理；建立了误差四元数的姿态组合模型，并采用反馈校正完成动态条件下姿态的确定；最后对姿态误差角进行了仿真研究，仿真结果表明该方法有效地抑制了误差的发散。

Aiming at the divergence of attitude calculation error in Gyro-Free Strap-down Inertial Navigation Systems(GFSINS),a magnetometer aided GFSINS scheme was proposed,in which the attitude calculation errors of GFSINS could be adjusted by geomagnetic information of magnetometer,and the precision of attitude calculation could be improved.The relation between the magnetometer output and attitude angle was derived,based on which an optimization algorithm of attitude was given,and the theory of the optimization algorithm was introduced.A model based on the quaternion was established,and attitude determination was implemented with the feedback correction.Finally，simulation was made on the attitude errors,and the result showed that the divergence of errors was controlled effectively.