| Parallel Robot (PR) is characterized by the high rigidity, large load handling capability, and non-accumulation of position error. PR is the supplement of Series-Robot (SR) and has become the focus of research in robotics. At present, PR has extensive and important applications in many aspects such as space flight, aviation, busywork in sea and land, underground exploitation, manufacturing, computer-aided medical instrument, biological engineering and micro mechatronics system and so on.However, despite the plentiful research achievements in the practical application and theory study in 6-DOF PR, there are many challenging problems in mechanics, kinematics, dynamics, singular pose, kinetic control and path planning. In this dissertation, Based on the laboratory model made by Yanshan University under the pecuniary aid of the Natural Science Fund, the dynamics and control strategies of PR were researched, in order to look for the practical and acceptable control strategies in engineering.Firstly, the structure, development survey and application prospect of PR are introduced in this dissertation. From the view of controlling, current development survey of control methods related to PR is presented subsequently. Currently the dynamics study of PR is not sufficient, so the dynamics model of PR is complex or established mechanically, which restrict the study of control theories and control engineering scholars. Thus this paper present a simple and easy-realized control idea, namely, the force and torque of every joints determined by the inverse-solution of mechanics about link mechanism are regarded as changeable load force (disturbance) applied in hydraulic servo system (hydraulic cylinder, and hydraulic piston), the displacement of hydraulic cylinder is regarded as the output of hydraulic servo system. Then the position close-loop is constituted and trajectory track control is realized.On the base of new-established model, an improved LQ control scheme is introduced to realize the trajectory tracking of robotic manipulators. Dynamics of link mechanism is regard as the disturbance on the hydraulic cylinder of servo system, so the robotic manipulators control become the control of servo system, with the robust for disturbance. To enhance anti-disturbance capability of system further, a discrete LQ optimal trajectory track control method with disturbance compensation is used. The simulation results validate the effectiveness and feasibility of the proposed scheme.Based on the device in existence, we do the real experiment. The results express that the control objects have been realized.In this paper, the trajectory tracking of robotic manipulators is also realized through Discrete Sliding-model Variable Structure Control (DSVSC). The control method exercises the advantage of invariability to disturbance of VCS to the full and turn the anti-disturbance into reality.The trajectory tracking of PR is also realized by integrating CMAC Neural Network into PD controller. CMAC Neural Network learns the model of robot backward-dynamics and PD controller adjusts the error, in this way, the dynamic performance is improved and the robustness of system is enhanced greatly.Considering the presence of the uncertain factor in robot control, a robust-adaptive control strategy which does not depend on the dynamic model of PR is demonstrated. The robust -control schemes such as robust-adaptive control, robust-adaptive decentralized control and parameter decentralized robust-adaptive control are discussed in theory. The simplified structure controller is presented, which neither reckon the characteristic of backward dynamic nor the regress matrix during the control, decrease the calculation greatly, guarantees the asymptotic stability of track error and realizes the PTP control preferably.Finally, robust-adaptive decentralized control of PR is designed, aiming at the uncertain upper bound of PR model. Do not require the regress matrix, The only complex task is to estimate parameter of uncertain upper bound, which is...
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