| On account of the restriction of existence technique of sensor and artificial intelligence, it is not realism to complete various tasks for robot autonomously. The concept of a telerobots system has emerged to reduce the risks facing workers by employing robots in a hazardous environment at a time when the scope of human exploration expands into even an unknown environment. The main function of a teleoperation system is to assist the human operator to perform complex or uncertain tasks in hostile environment, such as nuclear power plant, undersea exploitation, space investigation, life-saving, terrestrial mining, construction, military and police operations, etc. As a kind of special robot, telerobotics system is an effective approach to account for complicated task in uncertain and extreme environment possesses very important status in robot family. And as an important human-machine interface, the study of force-feedback manipulate device has been paying more and more attention to by the researchers.The existing force-feedback manipulate devices, which have been mostly adopted electrical torque-motor as the drive component, the force feedback range have been limited on account of the block up electric current, results in the simulation of teleoperation robot manipulate big load and the force presence effect relatively unperfected. As the developing of mechanism, electricity and fluid power technology, the foundation of developing force-feedback devices driven by electro-hydraulic servo system have been established. Developing new types force-feedback devices which can simulation telerobotic manipulating big stiffness have important significance and applied foreground.This Ph.D. dissertation developed under the project named"Force bilateral servo control of the teleoperation six-degrees-of-freedom (6 DOF) hydraulic parallel manipulator (No.50475011)"supported by National Natural Science Foundation of China and"Study on new type force sense bilateral servo control of teleoperation construction robotic"supported by Excellence Youth Teacher State Program of Ministry of Education (2003). This dissertation aiming at the force-feedback device and the control theory as well as the control strategies of master-slave teleoperation system, a new type device driven by electro-hydraulic servo system is put forward. Aiming at the force-feedback stiffness extremely small and force-feedback effect unconspicuous of the existing devices, a two-degrees-of-freedom (2 DOF) force-feedback device based on two-channel electro-hydraulic servo swing motor servo control system is put forward and developed. The control theory and control strategies of master-slave teleoperation system are analyzed. The mathematic model of the master-slave system is established and the control system design as well as the performance analysis is implemented. Finally, a testing experiment on test-bench of teleoperation system constituting of two same 2 DOF force-feedback devices is carried out to validate the performance and availability of control strategies. The main research work and innovative results of the dissertation are summarized as follows:1. In order to research the two degree of freedom (2 DOF) force feedback manipulator, the control theory and bilateral servo control strategies of master-slave teleoperation robot system with telepresence is studied in detail. According to the alternate combined manner of the kinetic and force information of the master side and slave side, the inherence relationship of the four channels control architecture, three channels control architecture and two channels control architecture are pointed out based on state-space model of the master-slave teleoperation system, and the performance analysis of the control architectures are carried through. The analysis results can provide the reference to the bilateral servo control system design.2. The key technical characteristics of existing force-feedback manipulator relating to develop force-feedback device, including performance requirements, structure design, performance evaluate, drive manner, measure and control system, are analyzed in detail. Based on this, the design scheme of 2 DOF force-feedback manipulator driven by electro-hydraulic servo valve control swing motors is put forward for the first time inland. The structure of the transmission shafts are designed in detail, the main component is selected. The kinematics and dynamics equations of the machine are set up, and the drive capability, isotropy and control stiffness, as well as manipulation performance are analyzed.3. When the isomorphic master-slave teleoperation system is adopted, the mapping of master-slave is simple and intuitionistic, and the problems can be discovered easily. In order to verify the performance of the electro-hydraulic servo 2 DOF force-feedback manipulator and the validity of the bilateral servo control strategies, test-bench is built up by two 2 DOF devices. The hardware and software of measure and control system of the master-slave teleoperation system are designed to constitute the force telepresence system. The experiment is achieved under the zero load and elasticity load by using different bilateral servo strategies respectively, and results shown that the 2 DOF force-feedback manipulator developed in this dissertation can be provided with large control stiffness, stable performance, rapid response, upper displacement control and force-feedback precision as well as the feedback force range can be adjusted to satisfy the requirements of the teleoperation robot.Furthermore, the following research works are put up in this Ph.D. dissertation:1. The development trends, application areas and research focus of teleoperation robot are introduced according to phylogeny of telerobotic technology. The characteristics of telepresence, force telepresence and bilateral control technology are emphasized. The state of arts, existent problems of teleoperation technology especially force-feedback device are analyzed. The research and developing motive and sense of the new type force-feedback device are brought forward. Finally, the main contents are made certain based on the research results of the predecessor.2. It is well known that the performance of force-feedback device can only be exhibited in the master-slave teleoperation system, and the operation performance of the force-feedback device is influenced directly by control theory and bilateral control strategies of master-slave teleoperation system. The passive control technique and strategies based on electro-circuit network theory along with modern control theory are analyzed. The control technique characteristics of master-slave teleoperation system with telepresence are construed inland and oversea. The dynamic model of the master-slave teleoperation system is set up. And the stability conditions, the relationship between the ideal performance and stability of the manipulator are studied by two-port-network model.3. In order to study the performance of the hydraulic system of the 2 DOF force-feedback manipulator, the model of the 2 DOF electro-hydraulic servo valve control swing motor hydraulic system is set up, and the decoupling conditions of two channels valve control motor hydraulic system is educed by simplification of the model. Based on the hydraulic decoupling, the model of the valve control motor force servo control system is deduced, and the dynamic characteristic of the system is studied.4. In order to improve the performance of the manipulator, disturbance observer is adopted to compensate the external disturbance, and simulation is carried through for the system. Toward the nonlinearity and parameter uncertainty of the force servo system, the nonlinear model is established and differential geometry technique is employ to nonlinear optimization control of the system. The optimized controller is designed and the simulation is implemented. The results can provide foundation to improve the device performance and to the controller design.The results shown that the 2 DOF force-feedback manipulator based on electro-hydraulic servo valve control swing motor 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 teleoperation 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 teleoperation system.
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