基于微机电系统(MEMS)的自主式行人导航系统通常安装在步行者的足部,利用零速校正来提高系统的定位精度。针对零速校正航向不精确问题,提出了基于等式约束卡尔曼滤波的双微型惯性测量组合(MIMU)行人导航方案。根据所设计的双MIMU系统在物理空间的相对位置关系,构造二阶非线性等式约束方程,并详述了等式约束卡尔曼滤波的解算过程。结合MEMS真实试验进行研究,对脚部负载双MIMU系统离线数据处理。根据试验结果验证了相比较于单MIMU行人导航方案,基于等式约束的双MIMU行人导航系统具有更高的定位精度。
Independent pedestrian navigation system which increases the accuracy of positioning through zero velocity updates(ZUPT)based on MEMS technology is usually foot-mounted.A dual miniature inertial measurement unit(MIMU)pedestrian navigation scenario based on equality constraint Kalman filtering is proposed,which focus on solving the problem that the heading can′t be precisely estimated during the procedure of ZUPT.Achieve nonlinear second order equality constraint with reference to relative position of two MIMU systems and work of data fusion applying a Kalman filter-type estimator in the presence of such constraint is reviewed.The considered scheme is researched with data in real MEMS experiment of foot-mounted MIMU,then off-line process the data of dual footmounted MIMU.According to the test results which is compared to a single MIMU pedestrian navigation scheme,equality constrained dual MIMU pedestrian navigation system has higher positioning accuracy.