Design And Experiments On Master-slave Plane Joint System Actuated By Artificial Muscles

Nowadays deep-sea exploration and development is enhanced due to the great needs of the country, therefore, underwater manipulators which are one type of the most important deep-sea equipment attract more and more attentions all over the world. The water hydraulic artificial muscle pertains to the application in underwater manipulators widely used in ocean development, with high force-to-weight ratio, fast response, and good bio-imitability. In recent years, more and more studies on the water hydraulic artificial muscle appears, using the muscle for the actuation of underwater manipulators. In this thesis, drive characteristics and control methodologies of master-slave joint system actuated by artificial muscles are investigated. A water hydraulic artificial muscle actuated slave joint and a pneumatic artificial muscle master joint are set up to test the PID position and torque control methods. This research contributes to high accuracy and facility for maneuvering underwater manipulators.The thesis is outlined as following:In chapter 1, the state of the art of water hydraulic artificial muscles, artificial muscle joints and master-slave systems is introduced. Key problems of this thesis are analyzed. Purpose, significance and main contents are outlined.In chapter 2, the artificial muscle joints are designed and the relationship of the angle of rotation and rotating wheel radius is obtained. Materials and structures are tested by tension experiments. As a result, the roller chain is selected for connection of the water hydraulic artificial muscle joint.In chapter 3, a static curve for relationship of the rotation angles and operating pressures is derived from the modelling of the water hydraulic artificial muscle joint. The joint position control based on PID method and static test of the rotation angle are carried out on a setup built in our lab. Finally, the system frequency characteristic is analyzed and recognized.In chapter 4, the master-slave joint control methodologies are mainly concerned. First of all, the pneumatic joint position control and torque control were analyzed and tested, then the pneumatic joint control system and water hydraulic joint control system are set up together to achieve a master-slave operation. The influences of load and transmission gain of the feedback torque are investigated through experiments.In chapter 5, all the research contents are summarized, and the future research developments and outlooks are proposed.