Research On Active Vibration Control Of Gyrowheel System

The Gyro Wheel system is an innovative attitude determination and control device,which meets the development requirements of small spacecraft for small volume,lightweight mass,low cost and high level of integration.The tilt vibration will affect the torques output and attitude sensitivity of the Gyro Wheel system,and even cause the system instability.In this paper,the control of the tilt vibration is investigated.Firstly,according to the physical configuration of the Gyro Wheel system,the complete nonlinear dynamical equations of Gyro Wheel is established by using Lagrange equations,then,the tilt vibration model is obtained.And in order to analyze the tilt vibration characteristics and verify the effectiveness of active vibration control method,the mechanical simulation model of the Gyro Wheel system is built by using Sim Mechanics toolbox.Secondly,the effect on the stability of the Gyro Wheel due to changes in spinning velocity and moment of inertia of rotor is analyzed by using dual-frequency Bode method.Using the same simulation model with the first part,under the open-loop and closedloop conditions of tilt around transverse-axis,the tilt vibration of the Gyro Wheel rotor is analyzed in the time domain and the frequency domain.In addition,the characteristics of the tilt vibration along with the spinning velocity and the unbalance is analyzed.Thirdly,based on the torque coils of Gyro Wheel system,three active vibration control methods are presented.The mechanism analysis method is used to identify the correct torque based on the input torque and the amplitude ratio and phase difference of the output tilt.The influence coefficient method is used to identify the correct torque according to the linear proportional relationship between the output tilt and the input torque.The phase priority determination method inspired by the concept of trial,first of all,based on the minimum amount of tilt vibration,the phase of correct torque is determined.After which the amplitude is determined.According to the simulation results,all of three active vibration control methods mentioned above can control the tilt vibration.Finally,based on the experimental platform of Gyro Wheel prototype,experimental results are presented to verify the effects of the latter two active vibration control methods.