Simulation of vibration characteristics of IMU with controllable magnetorheological isolation system

An important way to improve the dynamical test accuracy of an inertial measurement unit (IMU) is to suppress its vibration. In this paper, the dynamics model of a laser gyro strapdown IMU is developed based on the Riccati transfer matrix method for multibody systems. The vibration responses of the elements in the IMU system and the IMU isolation system under different excitations are calculated numerically. Combining with different control algorithms, the acceleration of the IMU shell is taken as the control object and the vibration characteristics of system are analysed. The simulation results show that only "internal damping " mode cannot achieve a good damping effect. The working situation of the IMU can be significantly improved by adopting magnetorheological elastomer isolators with fuzzy control. This provides a new technical means of upgrading the output precision of IMU.