Online Calibration Method of DVL Error Based on Improved Integrated Navigation Model

For the strap-down inertial navigation system (SINS)/Doppler velocity log (DVL) integrated navigation system, the installation error angle and the DVL scale factor error are the key factors affecting the accuracy of the integrated navigation system. Aiming at this problem, based on the traditional Kalman filter calibration method, this article discusses the estimation of calibration parameters under different models. On the one hand, according to the observability of state variables, an improved calibration model is proposed, and the corresponding state equation and measurement equation are given. On the other hand, the traditional calibration model based on DVL 3-D velocity information is abandoned, DVL four-channel beam velocity information is introduced, a tight integrated calibration model is established, and a tight integrated model calibration method is proposed. Combined with the traditional calibration model and the two improved models in this article, the River test is designed. The experimental results show that the improved model proposed in this article has better calibration accuracy than the traditional model. At the same time, the integrated navigation results based on the SINS/DVL show that the model proposed in this article has a smaller position error.