Penetration detection and vital-information recognition for drilling rescue with ultrawideband radar in underground sheltered space

Extensive studies have been reported on the application of ultrawideband (UWB) radar in rescue operations in the case of accidents. However, the identification of vital information in underground shelter spaces should be further improved to ensure successful rescue operations in the event of accidents. Therefore, in this study, a UWB radar vital-information recognition system suitable for drilling rescues was designed and developed. In addition to revealing the transmission attenuation of UWB radar waves in rock masses with different metamorphisms and thicknesses, the effect of vital-information recognition was verified, and effective ranges of vital-information recognition under different conditions were identified. The results indicate that the signal attenuation of the UWB radar wave increased with increasing rock mass thickness. The metamorphism of the rock mass was inversely proportional to the transmission attenuation of the UWB radar waves. Thus, the effective detection range for lignite and long-flame coal was 10 m, whereas that for lean coal was 15 m. When the thickness of the coal sample was < 3 m, the vital-information recognition error was < 1 m. These results have strong implications in ensuring energy safety and improving the survival rate of people trapped during accidents. • The attenuation of radar waves in rock with different characteristics was elucidated. • Effective ranges of vital -information recognition in different cases were proposed. • A UWB radar vital -information recognition system for drilling rescue was developed. • This work will enhance energy safety and the survival rate of trapped people.