The shock isolator is used for the protection of important equipment during firing, but due to the complexity of the recoil shock, currently most of them rely on experience for design, other than a more scientific design method. In view of this, this paper analyzes the recoil shock signal, proposes an analytical method to calculate the shock response, and develops a design method of shock isolator for sniper rifle under recoil shock. The reconstructed shock signal is obtained using least squares method, then an analytical calculation method of the response under recoil shock is proposed using the reconstructed waveform and Duhamel integral, the correctness of the analytical method is verified by numerical calculation and experiment. Using the pseudo-velocity shock response spectrum (PVSRS) of recoil shock, and combining with the anti-shock characteristics of protected equipment, a design method of shock isolator for sniper rifle is proposed, and the method is verified by analytical calculation and experiment. This method can provide a basic theoretical basis for the design of shock isolator using on sniper rifle, and can be applied to the design of other similar shock isolators.

This paper addresses the challenge of accurately measuring liquid level interfaces in multiphase mixed media by proposing a detection method based on ultrasonic transmission. First, a mathematical model of the ultrasonic measurement system was established, and the acoustic field characteristics of transducers with different frequencies and diameters in slurry were simulated and analyzed to determine the optimal excitation frequency and probe diameter. On this basis, an echo sound pressure calculation model based on the side-incidence method was constructed, and a formula for calculating the liquid level interface height was derived. Finally, an experimental test platform with a multi-layer steel container was built to measure the propagation velocity, attenuation coefficient, and acoustic impedance coefficient of ultrasound in the slurry, verifying the feasibility of the liquid level interface measurement method.