Design Of 6-DOF Hydraulic Manipulator And Its Control System For Nuclear Waste Treatment

The operating environment for nuclear waste processing has radioactive radiation,so the use of robots to perform tasks has gradually replaced manual operations.But so far,the handling and sorting of nuclear waste still have problems such as low work efficiency and high energy consumption.Based on the designed hydraulic manipulator arm,this paper conducts a more detailed research on its mechanical structure,kinematics analysis and hydraulic control system characteristics.The main contents are as follows:(1)Construction of the robot arm model.According to its working environment and the main parameters set,the overall plan of the robotic arm is designed,and the basic parameters such as the number of degrees of freedom of the robotic arm,the structure diagram,and the load are determined.the joint model of the manipulator is build by SolidWorks software.According to its structure and its quality attributes,the power components were selected and calculated by analyzing the force of the joints.Finally,SolidWorks was used to model the three-dimensional assembly of the robotic arm.(2)Establishment of mathematical model and dynamic simulation of mechanical arm.The positive kinematics model of the manipulator is established by The improved D-H method.According to the structural characteristics of the model,the inverse kinematics equation of the robotic arm is solved directly by algebraic method,and a posture matrix is chosen to be substituted into the equation for checking.According to the joint range determined above,its point cloud diagram is drew in MATLAB.Dynamic simulation is performed in the mechanical system dynamics analysis software ADAMS to obtain the torque curve diagram of each joint and verify whether the selected hydraulic components meet the working conditions.(3)The trajectory planning of the end of the robotic arm.In order to make the trajectory of the mechanical arm continuous and smooth during the movement,the linear interpolation method is used to determine its path in the Cartesian space,and the double S speed curve is used to plan the end speed.In the joint space,a fifth-degree polynomial is used to plan the joint rotation speed.Setting the driving function in ADAMS,and getting the curve graphs of the driving torque,speed,hydraulic cylinder thrust of each joint after two trajectory planning operations.(4)Hydraulic system design.Combining the structure and movement conditions of the robotic arm,the hydraulic system is divided into three sub-circuit hydraulic systems,which can realize the basic functions of the robotic arm.Combining load-sensing technology and electro-hydraulic proportional control technology,the preliminary designed hydraulic system Improve.The PID control algorithm is used to improve the input signal of the proportional servo valve,the hydraulic system simulation model is established through AMESim,and the position feedback control model is established.The displacement and thrust of the hydraulic cylinder in the trajectory planning are used as input signals,and the difference between the displacement and the actual displacement is calculated to verify the position feedback control accuracy of the system.