Performance evaluation of high g accelerometers

A numerical model for the split Hopkinson bar fly-away technique is presented to evaluate the performance of accelerometers measuring large amplitude pulses. Simulation results based on the numerical model indicate that the rise time of the incident stress pulse in the incident bar and the disk length are of appropriate lengths for the disk response to be accurately approximated as a rigid-body motion. Strain-time histories demonstrate that the incident strain pulse is non-dispersive. The rigid-body acceleration of the disk is derived from analytical models with stress at the incident bar/disk interface, incident strain-time data, and particle velocity on the free end of the disk calculated from numerical results. Thus, accelerations measured using the accelerometer and those derived from the models can be compared. These acceleration-time pulses show good agreement. The numerical model of the split Hopkinson bar fly-away technique can be used to calibrate high g accelerometers.