Velocity estimation and cooperative localization for AUV swarm based on factor graph
LI Xin-bin
YUAN Rui-xia
YAN Lei
HAN Song
Abstract：With the development of marine technology,autonomous underwater vehicles(AUVs)are widely used for executing collaborative missions.Accurate positioning of AUVs is fundamental for cooperative operation of a AUV swarm.However,in the cooperative positioning system,the asynchronous clock between AUVs affects the ranging accuracy,and the velocities deduced by the inertial measurement system have large errors.In this paper,we propose an error correction method by using distance measurement and Doppler shift measurement for the cooperative positioning problem in AUV cluster system.Firstly,the Taylor algorithm is used to estimate clock parameters,which solves the asynchrony of onboard clocks and in turn addresses the impact of clock asynchrony when obtaining distance measurements.Subsequently,a factor graph model is established with position and velocity information as variable nodes and distance measurement and Doppler frequency shift measurement as function nodes.The marginal distribution of the variables is calculated,and thus acquiring the estimated position and velocity information.Finally,in response to the errors caused by the linearization programs,a self-adapting factor based on the covariance matrix of variables in the message passing process of the factor graph is proposed to change the estimation of the variable nodes.Simulation results demonstrate that the proposed clock parameter can be accurately estimated.Additionally,the proposed algorithm is shown to effectively mitigate the cumulative errors of the inertial navigation system.
Keywords：autonomous underwater vehiclescooperative localizationfactor graphvelocity estimationasynchronous clock
Publication Date：2023-12-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：11( 2277-2287 )