Research On Integrated Navigation Method Of AUV Recovery

Autonomous Underwater Vehicle(AUV)is an important tool for human beings to go deep into the ocean.In recent years,it has become one of the focuses of world research.With the increasing complexity of the application market,auvs require longer battery life,more intelligent autonomy,and greater communication capabilities.Due to the limited power supply and poor underwater communication signal,it is necessary to timely navigation and positioning,distribution recovery for power charging,data exchange and update work requirements.This paper aimed at the problem of low recovery rate caused by poor underwater signal and low navigation accuracy of AUV in underwater recovery,combined with the basic characteristics of all-drive AUV,and participated in the development of AUV autonomous recovery experimental system,and carried out research on the new combined navigation method based on USBL(ultra-short Baseline)recovery.The main research included the development of fully driven AUV underwater recovery system,integrated navigation and positioning system and the lake test of AUV recycling.The specific contents were as follows:Firstly,this paper described the research status and development trend of AUV recovery system and acoustic combined navigation method at home and abroad,and according to the technical requirements of recovery and the self-developed "sea exploration type I" AUV,the recovery strategy and transformation plan of the recovery system were designed.Then,this paper focused on the integrated navigation method of AUV recovery based on USBL,it mainly includes the following aspects:(1)Aimed at the problem of singular value in distance iteration calculation of USBL positioning system,an improved gaussian distance iteration method and an improved Adaptive Kalman Filter(AKF)algorithm were proposed.(2)Based on AUV recovery docking system,the integrated navigation model based on slant distance for SINS,ultra-short baseline USBL,Doppler log(DVL)and depth meter was studied and established.Based on the analysis of error characteristics of SINS/USBL/DVL/depth meter combined navigation information,an improved SINS/USBL/DVL/depth meter combined navigation model based on slant distance was designed to solve the problem of USBL positioning system base array migration.(3)Aimed at the problem of filter divergence in this model,an improved AKF filtering algorithm based on filter convergence criterion and strong tracking filtering idea was designed for organic fusion.(4)Therefore,an asynchronous fusion algorithm based on SINS / USBL / DVL / depth meter integrated navigation system was designed.In this algorithm,the multi-scale system model was recursively obtained by mathematical induction;On the basis of establishing the multi-scale system model,the observation information on each scale was used to filter separately,and the global state estimation value was finally obtained by data fusion.Simulation results showed that this research on integrated navigation made the actual AUV system have higher filtering accuracy and reliability,and providing a guarantee for the safe recovery of AUV in the actual system.Finally,the design of "sea exploration type I" AUV and AUV recovery control system was expounded,and the design of AUV underwater integrated navigation software was introduced in detail.The AUV underwater USBL positioning experiment and underwater integrated navigation positioning experiment were completed,and the lake test experiment proved that AUV had a feasible and stable control system,and the integrated navigation system could meet the needs of recycling.