Patent ID: 11880208
Assignee: CHINA UNIVERSITY OF MINING AND TECHNOLOGY
Field: Control (Instruments)
Classification: CPC G | IPC G

Claim 2:
3. The method for drivable area detection and autonomous obstacle avoidance of unmanned haulage equipment in deep confined spaces according to claim 1, wherein in step S113, the process of performing image filtering processing on an enhanced image obtained in step S112 by using an image filtering algorithm based on bilateral filtering comprises the following steps:
S1131: for the enhanced coal mine roadway image obtained in step S112, constructing an n*n convolution template to carry out a convolution operation;
S1132: based on a spatial area and a range area, performing weight assignment on the convolution template in step S1131 according to the following formula:, {
  
   
    
     
      
       
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           2, where, Gα is a weight of the spatial area, Gβ is a weight of the range area, (xi, yi), (xj, yj) are respectively central pixel coordinates of the convolution template and pixel coordinates of the convolution template in step S1131, σ is a smoothing parameter, gray ( ) is a pixel gray value of the image, i is a center pixel of the convolution template, and j is a pixel of the convolution template;
S1133: according to the convolution template in step S1131 and the weights in step S1132, performing traversal computation of the left and right coal mine roadway images by using the following formula to obtain a filtered image:, {
  
   
    
     
      
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         ), where, S is the convolution template in step S1131, is an original input image, h is the filtered image, and wi is a normalization factor.