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The experiments have a key role in the initiation and transition studies of solid high explosives. Detonic has forced scientist to improve their experimental approach by designing relevant setup and developing accurate metrological devices. For example, the wedge or pop-plot test was developed in the 50's and remains a legacy experiment in the characterization of high explosive. However, for 70 years, it has been widely improved, because of the accurate measurements need. This paper aims to review the main improvements performed on the pop-plot test and analyze a series of results acquired on melt-cast and castcured high explosives. We first describe the current setup with its new metrological devices. Then, we discuss the results and limitations of this test.

A thermochemical code, SIAME, dedicated to the study of high explosives, is currently being validated. From this code, both the parameters of the JWL equation of state of a given composition are calibrated from the calculated adiabatic curve and tabulated equations of state are constructed. SIAME code uses BKW equations with a specific calibration presented in this study. Calculated adiabatic curves are compared with the one obtained with the American code CHEETAH with the BKWC, BKWS and EXP6 calibrations for two different high explosive formulations: a melt-cast one (RDX/TNT 60/40 % wt.) and a pressed one (HMX/ Viton 96/4 % wt.). The validity of the constant entropy curves obtained with the JWL EOS and the tabulated EOS is investigated from the Chapman-Jouguet state to several dozens of megapascals to cover all the high explosive effects. Experimental results obtained for the two high explosives with the cylinder test and the impedance matching test are presented in this study and offer a set of validation points.

In this paper, we demonstrate that a compact and inexpensive interferometric sensor based on the self-mixing effect in the laser cavity can be used for the characterization of shock waves. The sensor measures the changes in the refractive index induced by the shock wave. It is based on the self-mixing interferometry scheme. We describe the architecture of the dynamic sensor and the design of the experimental setup used for the characterization that involves a shock tube. Thus, we detail the experimental measurements for shock wave pressure amplitude of 5 bar and address their interpretation with regard to the most admitted models for acousto-optics.