一种在较大初始数学平台误差角下提高AUV自主导航精度的新方法

o strapdown inertial navigation system (SINS) in autonomous underwater vehicle (AUV), launch shock or insufficient alignment time may result in considerable initial misalignment errors, and the header misalignment error is a major factor to reduce AUV position accuracy. In this paper, soon after AUV launch, dead-reckoning (DR) and strapdown gyro-compass alignment (GA) algorithms are synchronously executed using raw data from strapdown inertial measurement unit (SIMU) and Doppler velocity log (DVL). After a short-time of GA level tune stage, DR level attitudes are corrected to diminish level errors, but DR header is corrected only when GA is convergent during the azimuth adjustment stage. Header error between GA and DR is calculated, and DR position errors can be estimated by the similarity theory of DR course and AUV actual course. Hence, AUV navigation accuracy can be improved. In the end, the simulation results show that the proposed method can perfectly correct position errors related to initial misalignment errors, but excluding position errors caused by DVL scale error. In the simulation case, AUV position errors diminish to 18.9% after error compensation.