Adaptive Energy Absorbers for Drop-induced Shock Mitigation

Abstract

This study addresses the non-dimensional analysis of adaptive magnetorheological energy absorbers (MREAs) for drop-induced shock mitigation. The control objective to ensure that the payload mass comes to rest at the end of the available stroke of the MREA, that is, a ‘soft landing.’ The governing equation of motion of a single-degree-of-freedom system with an MREA was derived. The Bingham number was defined and its effect on the system response was examined. A comprehensive non-dimensional analysis was conducted using non-dimensional stroke, velocity and acceleration, where Bingham number and time constant were key parameters. An optimal Bingham number - based on drop velocity, payload mass, and passive damping - minimized the drop-induced shock loads transmitted to the payload by utilizing maximum damper stroke.

Keywords

magnetorheological fluids magnetorheological damper energy absorber impact damper optimal control Bingham number.

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