Dynamic modeling and open-loop analysis of a control moment gyroscope considering the influence of a flexible vibration isolator

Abstract The microvibrations that affect the output performance of control moment gyroscopes (CMGs) are important in spacecraft attitude control systems. To reduce the influence of vibrations, researchers have done much work to isolate the vibrations between the CMG and the satellite. However, the deformation of the flexibility isolator affects the direction of the angular momentum, which affects the dynamic performance of the CMG inverse. In this research, using the Lagrange’s equation, the dynamic model of the CMG-isolator coupling system with the exciting force of the dynamic unbalance torque, the CMG’s gyro torque and the gimbal motor torque is developed. Based on this model, the coupling relationship between the gimbal rotation and the isolator deformation is established. For this CMG-isolator coupling system, we conduct the simulations to study the influence of the flywheel speed and the isolator stiffness on the CMG’s output performance and its gimbal’s rotation. Finally, the experiments on a CMG prototype are conducted, which verify the dynamic model and the simulation results of the CMG-isolator coupling system.