SINS In-Motion Coarse Alignment Solution With Partial DVL Measurements

The partial Doppler velocity log (DVL) measurement problem is attracting more and more attention in the coupling period of strapdown inertial navigation system (SINS)/DVL integration system. However, it is seldom discussed in SINS/DVL coarse alignment period, where full 3-D velocity information is still a requisite for the existing attitude determination methods. To expand the initial alignment ability of SINS/DVL integration system under partial DVL measurements scenario, a novel beam velocity-aided SINS in-motion coarse alignment solution is proposed in this work. First, an initial attitude determination model is derived with DVL beam outputs, where the relationship between the original beam Doppler shifts and the initial attitude is investigated, rather than the direct DVL velocity output. Then, a Cubature Kalman filter (CKF)-based parameter estimation algorithm is explored for the nonlinear model. Simulation and field test data are employed to evaluate the performance of the proposed solution, where various DVL configurations and valid beam distributions are involved. The experiment results show the effectiveness of the presented mechanism, confirming the possibility of partial DVL-aided SINS coarse alignment scheme.