Semi-Active Vibration Suppression Mechanism of Space Flexible Manipulator Based on a Variable Damping Element

Vibration suppression of space flexible manipulators is critical for operational accuracy. Although semi-active control offers advantages in low energy consumption and stability, its practical application in flexible systems remains constrained by the rigid-flexible coupling nonlinear effects introduced by semi-active devices, which significantly complicate system modeling and control. Herein, this paper proposes a semi-active control method for flexible manipulators using magnetorheological (MR) dampers and establishes a high-precision dynamic model that incorporates MR effects and structural flexibility coupling. First, a mathematical model of the damper is developed to characterize the mechanical behavior of MR fluid before and after yielding, with model parameters determined through experimental data fitting. Then, the displacement field of the flexible arm is described using the finite element method (FEM), and a dynamic model of the flexible manipulator is constructed based on Lagrange equations. Finally, the damper-manipulator coupling is realized by the force transmission equation, and the rigid-flexible coupling dynamic model of the system is formed. The dynamic response is solved using the Newmark-[Formula: see text] method. Simulation and experimental results show that the proposed method exhibits significant vibration suppression performance under different working conditions. Furthermore, with the increase of the control current of the damper, the vibration suppression effect shows a nonlinear trend of increasing first and then decreasing. This phenomenon shows that there is an optimal damping parameter configuration interval, which makes the damping effect optimal. This paper uncovers the vibration suppression mechanism of MR damper-space flexible manipulator systems, providing theoretical support for variable damping technology in flexible manipulator vibration control.