Rough coal-rock boundary identification method for exposed coal walls based on multi-domain robust features of GPR images and improved FCM algorithm
TIAN Ying
LI Chunzhi
CHEN Shuo
WANG Zihao
LYU Fuyan
ZHANG Qiang
HU Chengjun
Abstract:In the confined space of mining faces,where sensor deployment is restricted,developing a coal-rock structural perception sys-tem based on a single ground-penetrating radar(GPR)device holds significant engineering value.The accurate identification of rough coal-rock boundaries on exposed coal walls represents a critical challenge in constructing such a system.To address the limitations of single-do-main or homogeneous multi-feature representations in fully capturing the electrical differences between coal and rock,and to overcome the accuracy degradation of the conventional Fuzzy C-Means(FCM)algorithm caused by its equal-weighting strategy,a rough coal-rock boundary identification method is developed by integrating multi-domain robust features of radar images with an improved FCM al-gorithm.Twelve electromagnetic features capable of characterizing coal-rock electrical differences are first extracted from the time do-main,frequency domain,time-frequency domain,and wavelet domain,and their effectiveness is validated through forward simulations.Subsequently,three rough-surface models with varying root-mean-square heights are constructed to compute the mean coefficient of vari-ation and Pearson correlation coefficients among features.Seven features—envelope area,pulse width,spectral centroid,phase variation rate,mean instantaneous frequency,mean instantaneous phase,and scale energy ratio—are selected to establish a multi-domain robust fea-ture space for identifying transition zones of rough coal-rock interfaces.Based on the FCM framework,position encoding,L1-norm dis-tance metric,fuzziness criterion,label median filtering,and ground-truth judgment strategies are introduced to enhance the perception of spatial continuity in coal-rock distributions.Furthermore,an attention mechanism is incorporated to dynamically adjust feature weights,enabling adaptive clustering of coal-rock transition regions.Finally,the spatial distribution characteristics of the coal-rock interface within the transition zone are utilized to achieve precise boundary identification.Experimental results demonstrate that the proposed method ef-fectively identifies rough coal-rock boundaries on exposed coal walls,achieving a recognition error of 2.6%.
Keywords:ground penetrating radar(GPR)rough coal-rock interfacemulti-domain featuresattention mechanismFuzzy C-Means(FCM)
Publication Date:2025-11-30
Online Publishing Date:2025-12-15(First online date of this platform, not the publication date of the document)
Pages:13( 229-241 )
Coal Science and Technology

Coal Science and Technology

ISTICPKUEICSCD
ISSN:0253-2336
Year, Vol.(Issue):2025,53(11)