中文摘要：

研究了基于距离量测的主从式自主水下航行器（AUV）协同定位系统观测性问题。主AUV可以利用装备的高精度导航设备进行精确定位，从AUV装备低精度导航设备，需融合主从AUV之间的距离量测进行水下定位。针对控制输入对协同定位系统可观测性的影响，建立了从AUV在主AUV体坐标系中的运动学模型，并选取主从AUV间的距离值作为观测量，利用基于Lie导数的非线性系统观测性秩判据分析了不同控制输入下协同定位系统的观测性。仿真结果表明，对于可观测的协同定位系统，从AUV的位置估计具有良好的收敛性和定位精度。

英文摘要：

Sections 1 through 3 of the full paper explain our observability analysis mentioned in the titile, which we believe is effective and whose core consists of： （ 1 ） in the leader-follower structure, the leader can use high preci- sion navigation system for precise localization but the follower is equipped with only low precision navigation sys- tem ; thus, the followers need to combine the range measurements to the leader for underwater localization ; （2） ai- ming at finding the influence of control inputs on the observability properties, we develop a kinematics model of the followers in the leader＇s body coordinate system; considering the range measurements as the observation, we per- form an observability analysis for the cooperative localization with different control inputs with nonlinear observabili- ty rank condition based on Lie derivatives. Simulation results, presented in Figs. 2 through 4, and their analysis show preliminarily that, for the observable system, the position estimation of each follower has a good convergence and positioning accuracy.