Decoupling Hydraulic Servo Shoulder Joint And Its Control System

Robot joint is a basic element of the robot system and the control system is the core of the robot system. They are two of the most important parts of the robot system which determine the function of the robot and influence the development of the robot to a great extent. Based on the analysis and summaries of the previouse and latest research achievements on the robot joint and its control system, a new type 3-DOF (degree of freedom) motion-decoupling hydraulic servo shoulder joint and its control system is designed and researched in this article.Firstly, on the basis of the ideal that a 3-DOF robot joint would be controlled more easily on the condition that it could realize motion-decoupling, the motion-decoupling mechanism is analysed and the motion-decoupling condition is acquired. Then design concept of a new type 3-DOF motion-decoupling hydraulic servo shoulder joint is proposed. Structure project and servo tracking project of the should joint are proposed.According to the design project, the spatial outline of the shoulder joint is layed out. Modern mechanical design methods such as 3D design and virtual design is applied to the detailed structure design of the joint. Then the component and assembly CAD drawings of the joint are completed.As far as the control theory of the shoulder joint is concerned, master-slavery style distributed control system structure which is composed of the upper and the lower computer is adpoted. The control systerm hardware which is composed of industrial computer and DC (direct current) servo motor network is set up and tested.Based on the control system hardware, the software system is programmed and debuged in the platform of Windows OS and Visual C++ 6.0. MSComm is used to realize the serial communication between the industrial computer and DC servo motor network.Finally, a physical prototype of the shoulder joint for experiment is manufactured. The hydraulic experimental system which provides power to the shoulder joint is set up. Then the function of the shoulder joint and its control system is tested after they are integrated. The test results show that the shoulder joint has attained many excepted function.DC servo technique and hydraulic servo technique are integrated in the motion-decoupling hydraulic servo shoulder joint. It has many advantages such as light weight, compact structure, agile motion, large output torque and easy control etc. It is firmly believed that the robot manipulator based on this shoulder joint will play a very important role in the technique improvement and popularization of the industrial robot.