https://doi.org/10.15407/iopt.2025.60.119
Optoelektron. napìvprovìd. teh. 60, 119-123 (2025)
L. V. Borkovska, V. P. Kyslyi, V. O. Morozhenko, Y. G. Seryozhkin, E. A. Solovyov, V. M. Nastych
ACOUSTO-OPTICAL INVESTIGATION OF RESONANT VIBRATION OF BURIED OBLECTS IN SOIL
The subject of the work relates to the solution of the problem of humanitarian demining, which, with the beginning of the Russian military aggression against Ukraine, has become relevant for our country. This work is part of a series of works on the creation of a laser-acoustic mine detection complex based on a laser Doppler vibrometer, which was created at the V.E. Lashkaryov Institute of Semiconductor Physics of the National Academy of Sciences of Ukraine. Its purpose is to study the vibrations of buried objects under various conditions to increase the accuracy of their detection and identification. Attention was paid to the study of the parameters of acoustic resonances in soils with different humidity. Simple for analysis objects were used for the research, which were round hollow containers made of metal and plastic. They were buried in river sand in such a way that the surface of the sand was parallel to the wide side of the object. The immersion depth was 10-11 mm. The excitation of soil surface vibrations was carried out by acoustic white noise in the frequency range of 50–1000 Hz using a loudspeaker. The sound volume on the surface was 92-94 dB. Acoustic vibrations penetrated the sand and generated seismic waves that interacted with the object. Studies have shown that the resonant response of the object depends on the interaction between the object and the environment. Sand acts as a medium that can damp or change the resonant frequencies of a buried object. It has been established that the change in the elastic parameters of the soil with a change in humidity changes the spectrum of surface vibrations above the buried object, shifting the resonant lines of surface vibrations to the region of higher frequencies. In this case, the width of the resonances increases. The studies shown that the laser Doppler vibrometer developed at the V.E. Lashkaryov Institute of Semiconductor Physics of the NAS of Ukraine can be successfully used in humanitarian demining, but it requires design changes to increase the signal-to-noise ratio.
Keywords: detection of underground objects, laser Doppler vibrometer, humanitarian demining.