Research On The Precise Mining Method Of Cobalt Crusts By Four-degree-of-freedom Mining Robot

The ocean bottom is rich in cobalt resources,which are attached to the upper layer of bedrock in the form of cobalt crust.The distribution of cobalt crusts on the sea floor is complex.The traditional spiral drum mining head will cause a large number of bedrock mixing in the process of cobalt crusts mining,which reduces the economic benefits of mining and is not conducive to the commercial mining of cobalt crusts.In order to improve the economic benefit,it is necessary to study the accurate mining technology of cobalt crust,improve the mining rate of cobalt crust and reduce the mixing rate of waste rock.This paper mainly studies the precise mining technology of cobalt crust based on the four degree of freedom mining robot.The main research contents are as follows:(1)Taking the improved conical mining head as the research object,the effects of the working parameters of the mining head on the pick load,specific energy consumption and chip cross-sectional area are analyzed.Taking the traction speed and rotational speed of the mining head as the optimization variables,the multi-objective optimization mathematical model of the pick load,specific energy consumption and chip crosssectional area of the mining head is established,and the working parameters of the mining head suitable for cobalt crusts with different thickness range are obtained by global optimization using genetic algorithm.(2)Taking the four degree of freedom mining robot as the research object,the coordinate system is established based on the D-H parameter method,the forward and inverse motion processes are analyzed and solved,and the kinematics modeling and simulation are carried out in MATLAB to verify the correctness of the mathematical model.Aiming at a certain terrain,the trajectory planning of the mining robot is carried out,so that it can adjust the position and attitude of the mining head according to the change of terrain,and complete the accurate mining of cobalt crust.(3)Taking the two degree of freedom manipulator of the mining robot as the research object,the dynamic equation is established by Lagrange method.Based on this,the design and Simulation of the controller of the mining robot are completed,and the trajectory tracking characteristics of the manipulator are studied.(4)Based on the physical and mechanical properties of real cobalt crusts,select appropriate materials and proportion to complete the production of cobalt crusts simulation material,complete the mining experiment of cobalt crusts simulation material by mining head with the working parameters optimized by genetic algorithm,and evaluate the mining effect of the test-bed from the two important indexes of crushing particle size and mining rate.