| Master-slave bilateral servo control technology with force telepresence can provide the operator with immersion feeling of operating the slave, which plays important role in the fields of military affairs, deep sea and universe space operation, super scale, micro/nano mechanism operation, micro medical etc. The force feedback manipulator is the key device of the bilateral servo control system, through which the operator can control the slave operating in the remote and obtain the information of the slave contacked with the enviroment, helping the operator fufill a task efficicently. Therefore, the researches on new type, high efficiency, high performance human-machine interface equipment and the control stratege of the master-slave operation system are the hot points in the teleoperation field.The common problems of the existing force feedback manipultor are: poor universal prevalence, less rigid and cann't provide adquate force feedback and so on. In order to overcome the shortcomings of the exsisting manipulators and solve the drawbacks of the exsiting control stategies, this Ph.D. dissertation is developed under the project named"Force bilateral servo control of the teleoperation six-degrees-of-freedom (6 DOF) hydraulic parallel manipulator (No.50475011)"which is supported by National Natural Science Foundation of China. The rigid 6-DOF manipulator with is firstly designed based on the Stewart parallel framework; direct-drive type of position deviation feedback control structure is put forward and analysis the stability and the transparency of the master-slave sytem; the first national isomorphism master-slave operation experimental system with force telepresence is set up and experiments are performed. The main researches and innovative results are as follows:1. New type of 6-DOF force feedback manipulator is designed. The 6-DOF force feedback manipulator is the national first force feedback manipulator with high rigid, compact structure, flexible movement. It resolves the problems such as poor generality, complex structure, less rigid and force feedback not enough of the existing force/hapic feedback manipulator2. Direct-drive and position deviation feedback control type of structure is proposed. The position deviation between the master and the slaves is employeed to drive the master, and the operation force on the master is employeed to drive the slave. This control strategy breaks the current bilateral servo control convention that followed by the international. The problem that the master suffers heavy impact when the slave contacts on rigid mass is solves. The transparece and the tracking features of the master-slave are also improved. 3. Set up the first national isomorphism master-slave operation experimental system with force telepresence. Freedom movement and constrained movement experiments of the slave were performed in the experimental teleoperation sytem. The results show: the designed manipulator has good mechanical perperties and operational performance; the teleoperation system based on position deviation feedback control strategy has certain stability and transparency, and the foce telepresence is significant. The manipulator design and teleoperation system are all achieved the goals of this research project. Other researches are:1. Researches on the movement space and mechanics properties of the manipulator with force feedback. On the theoretical basement of the mechanics and dynamics of the Stewart platform, by using three-dimensional modeling software Solidwork, manipulator entity is constructed according to its assembly relationship. Movement space is simulated, so that the movement space with a certain thichness is obtained, and there is no mechanical interference in the whole space. The manipulator output power is analysized with the screw theory and the relation function of one dimension force to six dimensions force.2. Set up mathematical models of bilateral servo control system and analysis the performance of the system. The components of the master-slave operation system based on the self-developed 6-DOF force feedback manipulator are detailed and the dynamic models are set up the transparecy and steability of the master-slave operation system are analysized by the circuit two-port network model.3. The state observer is applied to compensate the disturbance of the hydraulic servo control system. Point to the problem of the dynamic characteristics of the hydraulic cylinder, control valve differences, the state observer is used to compensate the disturbance of the hydraulic servo system, which effectively improved the performance of electro-hydraulic control system and thecontrol precision.The researches shown that the 6-DOF force-feedback manipulator based on Stewart developed in this dissertation can provide with fast response, convenient manipulate, good credibility, stable performance, large stiffness, satisfying the manipulator big load requirements of the tele-operation robot system, and the force-feedback stiffness extremely small and force-feedback effect unconspicuous of the existing electro-driven devices have been solved. The design scheme can provide reference for the developing the same type force-feedback device, and have academic and practical value for the widen use of master-slave operation system.
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