Experimental Technique Used to Measure Transient Waves through Solids

An experimental technique, based upon the principle of the optical lever, has been used to measure surface oscillations as small as 10μ in amplitude on a thick circular plate, while it deforms under explosive attack. The transient behavior of the plate was determined by means of a long focal-length, sweeping-image camera with a writing speed of 4 mm/μsec. In comparison with the Hopkinson method, the technique yields more information of equivalent, or greater, accuracy. Equations are derived that have been used in the analysis of the experimental data. Experimental results are given as an indication of the precision of the technique.