Design, Optimization and Experimental Verification of a Metal Rubber Isolator for Momentum Wheels

Abstract

The inertial actuator, such as momentum wheels, is the key mechanical component of spacecraft for attitude stability and accuracy maintenance. However, the inertial actuators are under excessive vibration during the rocket launch phase. In order to prevent the inertial actuators from structural damage and equipment failure, isolating vibration from the base must be considered. Metal rubber (MR) is a kind of porous functional damping material, manufactured through the process of entangling, stretching, weaving and molding of metallic wires. With its excellent mechanical properties of high damping, designable stiffness and environmental adaptability, MR is widely used in the area of aerospace and aviation for vibration isolation. To this end, a method to design and optimize a MR isolator for momentum wheels is developed. The MR isolator consists of a transverse groove spring and MR in parallel. A FEM model coupling the transverse groove spring and the simplified momentum wheel is established to assist in the optimization of the configuration of the spring, and the goal is to minimize the frequency bandwidth of the first six modes. The influence of the parameters on the frequency of the first six modes is also discussed. The MR is then designed to provide damping and additional stiffness. Finally, the performance of the MR isolator is analyzed by simulation and verified through experiments.