Improved precision of strapdown inertial navigation system brought by dual-axis continuous rotation of inertial measurement unit

When systemic rotation autocompensation technique is implemented in inertial navigation system (INS), inertial measurement unit (IMU) undergoes intentionally devised mechanical motions. This technique is one of the strategies of improving the system precision performance at the system level. A dual-axis continuous rotation scheme is introduced, and system error equation is derived. The behaviors of different errors are analyzed. It is concluded that the whole error of INS is attenuated effectively. The error model of the dual-axis continuous rotation INS is designed on digital computer, and the theoretical conclusion is validated.