Mechanism Design And Control Realization Of The Manipulator Actuated By Pneumatic Muscles

With the development of robot technology, it is hoped that a new type of manipulator with high precision, fast response, large loading capacity and other characteristics, but also a good compliant so as to obtain better security and self-recovery capability. Pneumatic muscles cause the attention of research scholars against this background. Pneumatic muscle is a new kind of pneumatic actuator, which has simple construction, highest power/weight ratio, good flexibility, and the characteristics close to the biological muscles. So that it has a broad application prospect in the area of biomorphic robotics, bionic medicine, service robot and so on. A manipulator which has three joints actuated by pneumatic muscles is designed in this thesis. It makes a new attempt for pneumatic muscles used in the field of humanoid manipulator. The main research works of this thesis are as follows:The scheme of the manipulator prototype system was presented and this system was composed of three subsystems, i.e. shoulder, elbow and wrist. Each joint can achieve two degree of freedom movements. The shoulder joint has two independent executing agencies to realize its freedom of movements respectively. The cross shaft is used in the elbow joint and wrist joint to achieve two degree of freedom movements. The structure of the manipulator is more compact, and it is easier to install and debug for the use of modular design.The static ideal model of pneumatic muscle was proposed on the basis of principle of virtual work. As the actual characteristics of pneumatic muscle are different from the ideal one, an improved static drive model of pneumatic muscle was given, it could compensate the complicated errors due to various factors by adjusting the contraction ratio. Some experiments were performed to validate these works and the results show their effectiveness.Based on the static model of the pneumatic muscles, got the theoretical model of the joints actuated by pneumatic muscles, and gained the conclusion that the linear relationship between joint angle and input pressure different of the pneumatic muscles. When the joint torque is constant, the proportional relationship exists between them. The test results verify the rationality and effectiveness of the joint model.The overall experimental platform of the manipulator prototype system actuated by pneumatic muscle has been set up for testing the whole performance of the manipulator. Analysis of the dynamic response characteristics of the joint actuated by pneumatic muscle was studied with the terminal joint of the manipulator as an example. The text prove that the dynamic response characteristics of the joint is good.