| The master-slave tele-operation system with tele-presence provides the operator with the interacting information of the slave manipulator with the environment through information feedback, which creates the operator's immersive experience and the interaction situation of the slave with the environment. Based on that the operator can make correct decisions and the complex tasks can be completed effectively. The tele-operated robot can not only protect the operator's health and safety, but also extend the operational capability of people to help the operator to complete the operations which are difficult to complete directly, so the operation efficiency is greatly improved.The common problems of the exiting electric driven force feedback control device are: weak force feedback effect for its small force feedback; in order to obtain the interacting force effect of the slave with the enviorment, the interacting force is employed as the master's force feedback in the control structure, it would be unbearable for the operator when the slave suddenly contacted with the rigid objects. To solve the upon problems, with the National Natural Science Fund Project, this Ph.D. dissertation studied the theory of the force bilateral servo control of the tele-operation 6 DOF hydraulic parallel manipulator, built up isomorphic type of master-slave tele-operation experiment system and the whole information control strategies experimental researches were performed.Innovative results are as follows:1. On the base of analyzing the existing control structures, the master-slave position and force whole information bilaeral servo control structures were developed and made a reasonalbe simplification. Three channels and two channels such as"P-P+F"type of all in four kinds of possible simplified control structures were obtained. Theoretical analysis and experimental studies proved the effectiveness of the proposed control structures.In order to improve the reliability of the control signal, reduce the number of the interactive channel and solve the impact force on the master when the slave force changed suddenlly, deep research on the two channels were made and simplified position feedback control structure of only position sensor employed on the slave side was proposed. The effectiveness and feasibility of the control strategy are proved theoretically. The experimental results show that the control strategy gives great help on eliminating the impact force on the master.2. To solve the problems of small force feedback stiffness and weak force feedback effect of now existing electric driven force feedback manipulator, based on deep analysis of the technical features of now existing force feedback manipulator, 6-DOF force feedback manipulator based on electro-hydraulic servo control and driven by single rod cylinder is developed. Its special structure is both ends of the branch chain are connected by Hook hinge. Driving force matrix of every active kinematic pair is obtained and also the output force matrix of the hydraulic cylinder after researching its kinematics and dynamics, which forms the foundation for the master-slave control.3.Build up 6-DOF isomorphism master-slave teleoperation experiment system. The mechanical properties of the developed parallel 6-DOF force feedback manipulator and four kinds of control structures based on the whole information experiments were performed under no-load, flexible load and rigid load conditions. The results show that the tele-presence Stewart structure 6-DOF parallel force feedback manipulator has fast dynamic response, rigid structure, easy manipulation and satisfactory stability; in a variety of load conditions, the four kinds of control structures all have higher accruacy of position tracking and good force feedback effects. The whole imformation bilateral severo control strategy of F-P type of which force sensors are saved on the slave side can effectively elimanite the impact on the master, improve the system's operational performance and overcome the problems of the existing control straegies.Other research works of this thesis are:1.Deeply analyzed the interactive technology and tele-presence technology, especially the features of force tele-presence technology.2.Made research on the control performance of master-slave bilateral control systems: stability and operating performance. Passive stability, realization and determination method and also its ideal performance conditions were studied.3.Established the mathematical model of hydraulic cylinder with single rod out controlled by nozzle-flapper valve. Dynamic characteristics were studied which forms the foundation of studding the performance of the hydraulic system based on electro-hydraulic control of 6-DOF force feedback manipulator.4.The bilateral tele-operation system control is realized by employing impedance controller on the master side and sliding mode controller on the slave side. Desired objectives were achieved by performing different control structures experiments, which provided an experimental basis for 6-DOF master-slave control.Studies show that the whole information bilateral servo control strategies presented in this thesis are effective when used in the teleoperation system. It has obvious effect of telepresence and certain transparency, additionally, it resolves the problems of the existing force feedback devices. The results have theroretical and practical significance.
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