Electromagnetic Signals Analysis Method of Coal-rock While Drilling for Anti-punching Drilling Robots

Drilling pressure relief is the primary measure for preventing and controlling impact ground pressure in high stress mines, while accurate identification of coal and rock in the drilling process is a prerequisite for improving the efficiency of drilling pressure relief and guaranteeing intelligent drilling operation. In this paper, we propose a novel time-frequency analysis method of electromagnetic reflected waves of coal and rock while drilling based on CWT and GAPSO-ROA to extract the key time-frequency information of electromagnetic signals for enhancing the accuracy of coal and rock recognition. First, coal and rock drilling electromagnetic detection experiment is carried out to obtain the electromagnetic signals, including lignite, bituminous, anthracite, shale, mudstone, and sandstone. Then, time-frequency analysis method is designed combining the continuous wavelet transform (CWT) and the hybrid swarm intelligence optimization algorithm (GAPSO-ROA) to extract the key time-frequency information of the electromagnetic signals, which more accurately identifies the coal and rock. The experimental results verified the superiority and feasibility of the proposed method.