With the rapid development of the modern manufacture, industrial robot makes a more important role in modern industry. A lot of researchers have devoted their efforts to modeling and control of robot based on the rigid model. Nevertheless, industrial robots generally have flexible elements in the transmission systems which introduce flexibility into the joints. Especially for a high-speed operating robot with large load, joint flexibility is remarkable. Joint flexibility will decrease the natural frequencies of robot and vibrations are easily induced by the external force and inertia force. These vibrations may limit the trajectory accuracy and positioning precision, destroy the system stability and reliability. Therefore, the control algorithm designed assuming perfect rigidity at joints has limits in high precision robot control. In order to improve dynamic performance and quality of industrial robot, joint flexibility should be taken into account in both modeling and control and vibrations should be reduced. In this thesis, joint flexibility is considered and vibration control methods for industrial robot are studied. First of all, the research background and research significance of this paper are introduced. Then reasons of the joint flexibility and the research history of the flexible joint robot are summarized. A survey of work concentrated on the vibration control of flexible joint robot is presented and problems faced in vibration control for industrial robot are also analyzed. Based on the review and analysis of vibration control method for flexible joint robot, the research work is conducted. The main work and contributions of this thesis are: Firstly, the dynamical model of the rigid link flexible joint (RLFJ) robot with the structural of industrial robot is built based on the Lagrange energy method. Moreover, the vibrations properties of the model are addressed and vibration control methods are studied based on this model. Secondly, a novel trajectory planning algorithm is proposed which can insure the continuity of the positions, velocities, accelerations and jerks. Besides, the algorithm can be used when robot is at singular configurations with the inexistence of velocity. Finally, the algorithm can be applied to on-line tasks as well as off-line tasks. A forth-order feedforward controller is used in the control system to reduce the vibration of the robot in some extent, which can use the smoother trajectory information from the propo...
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