| Recently,because of its faster movement speed and less energy consumption,the flexible link manipulator has been widely employed in industrial manufactory,daily life,aerospace field and so on.However,due to the low stiffness of its link,the flexible manipulator may vibrates during the motion,which affects the motion precision of its tip.At the same time,the vibration can not be eliminated quickly only by the damping of the flexible manipulator itself.It is a challenge for the flexible link manipulator controlling.Therefore,this paper proposes a control method of the single flexible link manipulator with controllable damping,which can track the desired trajectory and suppress vibration.This paper will be organized as follows:In chapter one,a wide range of applications and the significance of the research of the flexible manipulator are first introduced.The researches of the flexible manipulator are also introduced at home and abroad,including the modeling methods,identification approaches,control methods and the vibration suppression devices.At last,the main aspects of the research and the article organization structure are explained.In chapter two,the dynamic model of the flexible link manipulator is established.The bending vibration equation of the cantilever is analyzed.Then,the complete dynamic model of the flexible manipulator is established based on the extended Hamilton's Principle and assumed model method,taking into consideration of the higher order modal truncation error of the flexible manipulator.The flexible manipulator actuator is taken as a simplified DC motor model with Coulomb friction.Finally,the motion of the flexible manipulator is analyzed according to the dynamic model of a rotating motor-driven flexible manipulator system.In chapter three,the system identification is conducted to estimate the unknown parameters of the flexible manipulator.Four identification methods are proposed for the flexible manipulator,including frequency domain identification,least square identification,subspace identification and subspace identification with compensation model errors.Then,the system excitation signal of model parameter estimation is designed and the identification results are analyzed to compare the accuracy of the aforementioned identification methods.In chapter four,an adaptive robust controller(ARC)is designed for the flexible manipulator tip tracking and vibration suppression.The design difficulties of the controller of the flexible ma-nipulator are analyzed.Then the ARC is designed based on the dynamic model of the flexible manipulator.Adaptive model compensation control is adopted to eliminate the influence of un-certain parameters.Robust feedback control is adopted to restrain disturbance.Vibration feedback control is adopted to suppress the small tip vibration.Theoretically,the Lyapunov stability of the designed closed-loop system is proved.Finally,the comparative experiments are conducted on the rotating flexible manipulator testing bed,including the proposed ARC,the conventional PID controller and LQR controller.The results show that the proposed algorithm not only achieves the tracking accuracy,but also reduces the vibration.In chapter five,the control method for the flexible manipulator with controllable damping is presented,to achieve the dual objectives of vibtration suppression and tip trajectory tracking.First,the experiment platform is designed as the linear motor driven flexible manipulator with magnetorheological damper.The whole dynamic model of the flexible manipulator with magne-torheological damper is established by Lagrange method.The control method for the flexible ma-nipulator with magnetorheological damper is designed by damping control combined with ARC.At last,the simulation results verifies the effectiveness of the proposed control method.In chapter six,the whole paper is summarized and the prospective study of the flexible ma-nipulator with magnetorhological damper is explored. |
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