Miniature Shock Absorber Based on SMA Foil Actuation

The design, fabrication and performance of a novel Shape Memory Alloy (SMA) foil-based shock absorber are being presented. A cold-rolled NiTi SMA showing one-way Shape Memory Effect (owSME) at room temperature is used for the device fabrication. We explore the damping behaviour under vertical shock loading. Most of the energy associated with the shock loading is dissipated by material hysteresis. Shape recovery using a short duration heating pulse below 100 ms enables near-adiabatic heating of the device. The shock response of the shock absorber is governed by the recovery force of the SMA device upon application of heating pulse, enabling mass stabilization without oscillations. The recovery time and settling behaviour remain nearly identical irrespective of the mass and device pre-strain, while maintaining a constant total loading strain on the device.