DVL/SINS松紧组合的等价性分析及改进的虚拟波束辅助紧组合算法

Equivalence analysis between DVL/SINS loosely and tightly coupled systems and improved virtual beam-aided tightly coupled algorithm

系统地研究了不同波束可用情况下的多普勒计程仪(Doppler velocity logger,DVL)/捷联惯性导航系统(strapdown inertial navigation system,SINS)紧组合导航算法。证明了3个或4个波束可用情况下,DVL/SINS波束域紧组合的定位精度与三维速度松组合系统具有等价性,并给出了松组合中量测协方差阵的确定方法。针对紧组合系统定位精度随可用波束减少而降低的问题,考虑DVL的误差参数,基于载体运动约束和压力深度计提出一种改进的虚拟波束辅助紧组合算法。实验结果表明,3个或4个波束可用时的松组合与紧组合的定位精度等价;改进的虚拟波束辅助紧组合算法可以准确跟踪故障的波束速度,有效提升了不同波束可用情况下紧组合的定位精度。

This paper systematically studies the Doppler velocity logger(DVL)/strapdown inertial navigation system(SINS)tightly coupled navigation system with different available beams.It is demonstrated that the positioning accuracy of tightly coupled system for DVL/SINS beam domain is equivalent to the 3D velocity-aided loosely coupled system when three or four beams are available,and the determination method of measurement covariance matrix in loosely coupled system is given.To address the problem that the positioning accuracy of tightly coupled system decreases with the reduction of available beams,considering the error parameters of DVL,an improved virtual beam-aided tightly coupled algorithm is proposed based on the motion constraint and pressure sensor(PS)measurements.Experimental results show that the loosely and tightly coupled systems have equivalent positioning accuracy when three or four beams are available,and the improved virtual beam-aided tightly coupled system can accurately track the velocity of outage beams,which effectively improves the positioning accuracy of tightly coupled system when different beams are available.