Research On Autonomous Task Fuzzy Control Technology Of Four DOF Construction Robot

During the process of exploitation of the sea, underground resources and astrospace, Tasks are often carried out in the limit working environment which is difficult or hazardous for mankind to approach such as high temperature, high pressure, strong radiation, suffocation etc. In order to complete the complex operations in such harsh circumstances, the teleoperation construction robot technology based on the telepresence has been used widely. Due to the interference of the cosmic rays and the limitation of the transfer condition, the signals being sent back are always with noises and remarkable length of time-delay, the system will be unable to work normally in severe situation. In recent years, the teleoperation construction robot system having autonomous function has been asked for. When the transmission lines are disrupted and teleoperation can not be carried out, the autonomous task system still can complete the key task which must completed in the part-time independent nodes automatically. Such research and development have great theoretical significance and practical value.This thesis combines the project of national natural science fund (No. 50475011), does extensive investigation on domestic and international research on robot intelligent control technology, relying on the experiment platform of four degree of freedom teleoperation hydraulic-servo manipulator in mechatronic engineering laboratory of Jilin University, sets up a autonomous task digital PID control system and fuzzy control system of construction robot, researches and develops the autonomous task control system of the construction robot.In order to realize the Autonomous Task of construction robot, the thesis firstly, using coordinate transformation method, has established the four degrees of freedom construction robot's kinematics equation and the relation of the manipulator various joint angle to its gripping device terminal position .Secondly, The research on the control algorithm about autonomous task of construction robot is studied in this thesis. In the digital PID control algorithm's foundation, the fuzzy controller based on fuzzy control theory is designed. Thirdly, capture detection and clamp judgment technology between the manipulator and the target object were studied in this thesis. Capture detection and clamping judgment are the basis judge that whether the target object has been transferred to appointed position according to the pre-setting path. Finally, the autonomous task control experiments are carried out on the four degree of freedom construction robot platform. The test contents include identification of target objects and spatial positioning, trajectory planning and capture judgment.The thesis consists of six chapters, The main content of each chapter has been accomplished as follow:(1) The thesis outlines the development history of robot control theory and introduces the development about robot control technology. The present technology of robot intelligent control is analyzed, and then the development orientation of autonomous task fuzzy control technology of four degree-of-freedom construction robot is made certain.(2) A scheme of autonomous task control system of four degree of freedom construction robot is designed. The principle and composition of autonomous task control system of four degree of freedom construction robot are expatiated. The functions and mutual relations of each subsystem﹑the sensor and equipment which are used in the experiment are introduced.(3) The thesis, using coordinate transformation method, has established the relation of the manipulator various joint angle to its gripping device terminal position. The construction robot's forward kinematics equation and the inverse kinematics equation have been inferred, and the validity of kinematics equation has been confirmed through the simulation analysis. (4) Aiming at the construction robot's structure and movement characteristics, as well as to the performance analysis of the autonomous task of four degree of freedom construction robot, based on the conventional PID controller, for the purpose of improving the stability and reliability of the construction robot's movement, The autonomous task fuzzy controller of construction robot is designed.(5) The four degree of freedom construction robot was taken as the study object, and then the complete autonomous task fuzzy control system of construction robot is structured, and by successful trajectory planning and target grasp detection and control, the autonomous task of construction robot is preliminarily realized. From the experimental the empirical datum chart 5-11, the thesis can be drawn that fuzzy control enhances 50% compared to the conventional PID control in response time.(6) The summary about my thesis is given and what should be done in future research is also described. Proved through the experiment that the autonomous task fuzzy control system of the four degree of freedom construction robot have preliminarily been able to complete their task, and the task process is smooth. The research work done in this article provided valuable experience and success examples for the deeper autonomous task technology of the teleoperation robot in the future.