A Low-cost MEMS IMU/DVL/Pressure Sensor Integrated Navigation System for Autonomous Underwater Vehicle

An integrated underwater navigation system for AUV is presented. The system uses a 3DM-GX1 MEMS IMU with the aided by a DVL and a pressure sensor. To reduce the effect of inaccurate depth data, a complementary filter can be deployed to estimate the depth of the AUV. With a Kalman filter and complementary filter, a novel algorithm based on MEMS IMU /DVL /Pressure sensor integration has been developed for the AUV. The advantage of the novel algorithm is that it can estimate all the bias of inertial sensors using minimum error state numbers. Both numerical simulations and field test were implemented based on the type of IMU, DVL, pressure sensor and a magnetometer used in this study. The results of simulation show that the attitude error can be estimated thoroughly and be corrected using DVL and magnetometer. The estimated position error of the integrated navigation system is confined with 1.5 meters after 4000 seconds. The test result also shows that this robust MEMS IMU/DVL/Pressure sensor integrated system has the capability of providing continuous and reliable position information for autonomous underwater vehicles.