Path Planning Method For AUV Underwater Terrain Matching Navigation

Precision navigation system is the key to ensure its security and stability work, for AUV(Autonomous Underwater Vehicle) working for a long time and in a large range. In traditional, the INS(Inertial Navigation System) and DR(Dead reckoning) will get a cumulative error, which could be very huge to AUV, with the increase of heading distance and time. The Terrain Matching Aided Navigation method would solve this problem from INS or DR well, which only requires the underwater terrain information, avoiding AUV floating for GPS. This advantage makes sure that AUV would work underwater for a longer time and better hiding. This paper aims to make a proper path planning for AUV stably working underwater for a long time and in a large range.Firstly, this paper gives an account of matching algorithm using in TAN(Terrain Aided Navigation), such as TERCOM,Bayesian Estimation and SITAN. These methods are described in detail about the basic principle, the matching process and the advantages &disadvantages. What's more,promoting various parameters used to measure the characteristics of area terrain, and giving their definitions, formulas and the range and so on.Particularly, explaining the terrain elevation entropy issues. By MATLAB simulation, verify that the smaller entropy, the better algorithm precise. Meanwhile, promoting the critical terrain elevation entropy and giving a way to find it. Thirdly, in order to make a proper path autonomous for AUV heading in a long way, this paper puts forward a new method which is called sector searching suitable area method. In this method, there are three parameters described in detail which are the sector angle, the limit line and the goal-aided area. It is also testified that the method could be effective by MATLAB simulation. Finally, through the artificial force field and the limitation of the critical terrain elevation entropy, finding a better way for AUV heading.This paper studies the adaptation problem of area terrain entropy, and puts forward the concept of critical terrain elevation entropy. At the same time, In order to find a path for AUV heading, puts forward the new method, sector searching suitable area method, searching the suitable matching area on AUV heading path. Finally, optimizing the path with artificial force field method and the limitation of the critical terrain elevation entropy.