Design and Experimental Verification of Position-Dependent Passive Electromagnetic Damping

Abstract

A linear dashpot is a common equipment used in shock and vibration isolation. It has been shown theoretically that the vibration isolation performance can be significantly improved by a damping profile that depends on the piston relative position. In this study, a position-dependent damping profile is realized by using electromagnetic principles. The idea is to have multiple coil windings on the outer cylinder and to use a magnet as a piston. The damping profile is tuned by changing the number of turns at each coil. As a result of the magnet-coil arrangement, the architecture also has the capability of being regenerative. A unique experimental setup is constructed that measures damping electrically in a multiple coil arrangement. Least-squares optimization method is used to tune the number of turns. It is shown that the coil turns can be successfully tailored to realize a desired damping profile. The position-dependent damping architecture has the potential to be used in future regenerative dampers.