The Research And Realization Of Attitude And Heading Reference System Based On MEMS Sensors Used For Ship

Low-cost Attitude and Heading Reference Systems based on MEMS inertial sensors have broad application prospects both in the field of national defense and civilian areas. The paper relies on the going project of the laboratory which is low-cost shipborne satellite antenna micro attitude measurement system, makes a study of correlation algorithms of an integrated attitude measurement system based on MEMS inertial sensors, magnetometers and GPS, and the approach is verified to be feasible and effectiveness by simulations.The work makes a foundation for the practical application of the MEMS Attitude and Heading Reference System on the shipborne satellite antenna stable system.(1) The large random drift of MEMS gyro is the great factor on impacting the accuracy of attitude algorithm. Aiming at the unknown nature of its error model, the paper establishes a gyro random drift of ARMA models using the time series analysis through the static test data, and applied it to the compare of the following attitude estimation algorithm.(2) On the condition of without GPS, taking the characteristic of the shipborne movement and the AHRS working application requirements into account, through the theoretical analysis and the comparison of simulation results about the various attitude updating algorithms, the paper finds that the calculational complexity of the modified Rodrigues parameter algorithm is significantly smaller than the quaternion algorithm and the rotation vector algorithm, the calculational accuracy is similar to the quaternion algorithm, while overcoming redundant when using quaternion to descript the attitude. It supplies the gist for choosing the attitude updating algorithm.(3) According to the above analysis, the extended Kalman filter for attitude estimation algorithm is derived with gyro bias and the modified Rodrigues parameters for the state vector and output of accelerometers, and magnetometer for the observation vector, and used the switch between the modified Rodrigues parameters and its shadow parameters to solve the singularity problem.. The validity and superiority of the algorithm are verified by the simulation under the conditions of the whole attitude and the swing movement.(4) To checkout the applicability of the ARMA model, through the simulation of the conditions of the static and swing motions, the paper obtained the conclusion that in static condition the estimation algorithm based on the ARMA model for gyro bias has higher precision both of the attitude estimation and the gyro bias compensation than the random walk model. However, under the conditions of swing movement the accuracy is less than the estimation algorithm with the random walk model for gyro bias, while the calculating amount is larger. Therefore, the MRP EKF estimation algorithm used random walk model for gyro bias has more universality. In the precondition of adjusting the observation noise variance matrix, to minish the output error ulteriorly in the condition of the gravity and magnetic vectors are disturbed, the GPS information is introduced, and carries out a study of loosely coupled Kalman filter algorithm for MEMS AHRS/GPS integrated system, and the simulation verified the feasibility of the algorithm.