Coupling analysis of shaking table and flexible centrifuge based on multibody dynamics

Abstract

Ground-based testing is essential for many aerospace systems due to the high costs and potential risks of flight testing. Currently, a combination of centrifuge and shaking table is generally employed in ground-based testing to create the linear acceleration and vibration environment experienced during spacecraft launches. However, the centrifuge arm, being a typical beam-like structure, fails to accurately reflect the dynamic characteristics of the combined system when regarded as a rigid body. To address this limitation, a rigid-flexible coupling dynamic model of the centrifuge-shaking table system is developed using the finite volume method and multibody dynamics, and dynamic analysis is performed using MBDyn software. The investigation focuses on the effects of rotation speed, tip mass of the centrifuge arm, and excitation force of the shaking table on the system's dynamic characteristics. The results indicate that as the centrifuge rotation speed increases, the displacement of the additional table increases rapidly, while the natural frequency of the shaking table decreases slightly. Furthermore, the tip mass primarily influences the deflection of the arm corresponding to the second mode shape, and the excitation force induces oscillations in the output angular velocity of the centrifuge arm. These simulation results underscore the non-negligible interaction effects within the combined system.