Nonlinear deformation measurement method based on IMU for ship

Ship deformation is generally divided into static deformation and dynamic deformation that are usually considered as a small angle. However, in real situation, it can be a large angle in heading direction between IMU in the large ship because of the limitation of IMU installation location, which leads to the nonlinear of the error model. Establishing the nonlinear error model and processing it with nonlinear filter can effectively solve the ship deformation problem above. The simulation results show that UKF method has more high estimate precision and faster convergence speed than EKF, which can reach less than 0.1´.