Validation of an Impulse Measurement Technique with High Temporal and Spatial Resolutions

We present a new experimental technique to measure the force-time history of high-velocity impacts and high pressure blast waves. The technique is based on the classic Hopkinson-type strain bar, coupled with an interferometric velocimeter instead of strain gauges. The major benefits of this setup are its accuracy, temporal resolution, and its imperviousness to electromagnetic interferences. We explain the keys concepts behind the technique and describe the experimental setup. We present experimental and numerical data as proof-of-concept and discuss preliminary studies on the effect of plastic deformation of the bar and its consequences on the interpretation of the measured impulse-history.