Adaptive Adjustment Method For Navigation Based On Integration Of Current With UUV’s Position And Attitude

Unmanned Underwater Vehicle (UUV) has been attributed to one of availabilityequipments for exploring marine environment. Its navigation efficiency and security havebeen a substantial focus for academicals and technical researchers. Current information ofunknown environment, as inputs to the filter designed, including speed and direction, can beobtained using Acoustic Doppler Current Profilers (ADCP). The output information of thefilter will assist to choose an appropriate path as UUV navigating. The navigation efficiencyand influence from cross-flow are considered primarily in the process of path optimization.The main contents in this paper are shown as following.Firstly, the reference frames, such as the global coordinate system, UUV bodycoordinate system, ADCP instrument coordinate system and sonar beam coordinate system,are introduced. And transform relationships between each two relation systems are analyzed.With appropriate transformations, the current information from ADCP is converted to becorresponding data in global coordinate, on the basis of which, the current disturbance modelis established.Secondly, filtering algorithm is designed by integrating current information with UUV’sposition and attitude. Current information is displayed using WinRiver and WinADCP.Considering noise interfused into current data as UUV navigation in complicated marineenvironment, an improved colorless Kalman filter method is introduced to filtering data. Thefeasibility of filtering algorithm is verified using current data, position and attitude of vehiclecollected in sea trial.At last, an adaptive adjustment method for navigation with current information filtered ispresent, and a comprehensive evaluation function taken into account the constraints fromnavigation efficiency and cross-flow is proposed. Under constant flow and time-varying flowconditions, it is validated that an appropriate path can be selected.In this paper, an adaptive adjustment method of dynamic planning is designed bycombining the position and attitude of UUV with current information measured using ADCP.Different cases are clarified to verify performance of the method proposed. Simulation resultsshow that the navigation time is reduced obviously and the disadvantage from cross-flow canbe avoided using method designed of Adaptive adjustment.