Profile Measurement And 3D Reconstruction Of Underwater Cobalt Crusts Simulated Material Based On Ultrasonic Thickness Measurement

Because the bedrock is undulating and the cobalt crust deposition rate is different,and the cobalt crust attached to the bedrock is non-uniform and irregular,the interface between the cobalt crust and the bedrock is a random complex spatial surface.To achieve precise mining of cobalt crusts along the interface between cobalt crusts and bedrock,reduce the mixing of bedrock,and improve the extraction rate of cobalt crusts,the key is to obtain the three-dimensional spatial distribution of cobalt crusts in the mining area to be mined before mining.Therefore,based on the93 kHz ultrasonic detection system,this paper studies the threedimensional orebody reconstruction method of cobalt crusts,and realizes the three-dimensional visualization of cobalt crusts.The main research contents are as follows:(1)Analyzed the Biot theory and improved BISQ theory of the acoustic propagation model for dual-phase porous media.Combined with the classical KC model in permeable media,the two independent acoustic propagation parameters of permeability and porosity are linked,the microscopic parameter permeability is eliminated,and the acoustic propagation model is simplified.According to the similar principle,the cobalt crust simulation material is prepared,and its physical and mechanical parameters are measured,and the sound velocity prediction model and sound attenuation coefficient prediction model suitable for the cobalt crust simulation material are established.(2)Based on the 93 kHz cobalt crust ultrasonic detection system,the sound propagation parameter measurement experiment is carried out.Through nonlinear fitting of porosity,sound velocity and sound attenuation coefficient,the sound velocity fitting formula and sound attenuation coefficient fitting formula are obtained.The coordinate values of the upper surface of the cobalt crust and the coordinate value of the interface between the cobalt crust and the bedrock are calculated,and the low-dimensional data for the three-dimensional reconstruction of the cobalt crust simulants material is determined.(3)Analyze the variogram of the sampling data obtained by the ultrasonic thickness measurement experiment,calculate the prediction error values of the spherical model,exponential model,Gaussian model of the upper surface sampling data and the interface sampling data,and determine the optimal theoretical model.The upper surface sampling data and the interface sampling data are encrypted by ordinary kriging algorithm.(4)Delaunay triangulation is constructed by point-by-point interpolation method to reconstruct the upper surface and the surface of the boundary surface of the mineral seam.Based on the shortest diagonal method,the upper surface mineral layer surface and the boundary surface of the mineral seam are connected by contour to realize the threedimensional reconstruction of the cobalt crust simulation material.The reconstructed 3D ore body of the cobalt crust simulation material can accurately reflect the surface characteristics and 3D thickness of cobalt crust.