One of the key technologies to solve the dilution problem of cobalt crust is to calculate the best exploitation depth by surface elevation information. A single-beam swing ultrasonic micro-terrain detection method was proposed based on occurrence of cobalt crust and mining method. To test the feasibility of the method a laboratory bench has been successfully built, and the fact that the detection accuracy of vertical bench can achieve centimeter level has been verified. Subsequently. an improved data windowing algorithm to further improve the accuracy of removing exceptional elevation value was submitted; linear correlation coefficient method was adopted to choose linear and nonlinear regression support vector.It is proposed and proved that Gaussian radial basis function parameter σ can be determined according to the slope, slope length information on measuring line.