Single-axis rotary inertial navigation system based on dual-IMU joint modulation

Abstract At present, large and medium-sized ships are usually equipped with two or more sets of inertial navigation systems, but the inertial navigation systems operate independently of each other, and this approach only improves the reliability of the navigation information, and does not improve the accuracy of the navigation information. Aiming at the above problems, this paper proposes a dual-IMU joint modulation scheme, which ensures that there is an IMU in pause at any moment by reasonably designing the rotation strategy of the two sets of IMUs, so as to combine the data of the two IMUs in the time sequence. The scheme utilizes the symmetry of the rotational position to eliminate the error, and at the same time avoids the coupling error caused by the rotational motion of the IMUs, reduces the periodic error, and improves the navigation accuracy. Semi-physical simulation test results show that the improved joint modulation scheme has superior modulation effect on the device errors of inertial devices compared with the traditional rotational modulation scheme.