Vibration Suppression Of A Flexible Manipulator Based On Sliding Mode Control

With the wide application of flexible manipulators in industrial robots and aerospace engineering,the research on vibration suppression of flexible manipulators becomes more and more in-depth.In this thesis,the modeling method and the design of the controller will be studied deeply,so as to realize the fast and reliable contro l.In this paper,the dynamic modeling of the flexible manipulator is established firstly.The flexible manipulator is abstracted as the Euler-Bernoulli beam according to the propert ies of the flexible manipulator.The Lagrange equation and the hypothesis mode method are used to model the flexible manipulator.The state space equation is calculated by the actual measured parameters.It provides a theoretical model for the follow-up research work.Based on the integer-order PID contro l theory,an PD contro ller for suppressing the vibration of the flexible manipulator is designed.Through the simulation and actual test,it is found that it can quickly realize the positioning process of the flexible manipulator,have a good suppressio n effect on the vibrat ion of the flexible manipulator,but the amplitude of vibrat ion is large.Secondly,the sliding mode contro ller is designed for the flexible manipulator by understanding the sliding mode contro l theory.Through the simulation research of the traditional sliding mode controller,it is found that although it can achieve the rapid positioning of the flexible arm,it will introduce high-frequency jitter phenomenon.Therefore,the sliding mode contro ller need to be improved,the integral switch gain sliding mode controller is designed.Through the simulation and actual test,it is found that it can meet the positioning accuracy,have a good suppression effect on the vibration of the flexible manipulator,and suppress the high frequency jitter.Then,by introducing the basic theory of fractional calculus,it is applied to the design of sliding mode contro ller.A fractional exponential approximation law sliding mode controller is designed for the flexible manipulator.Through the simulation and practical test,it is concluded that it can achieve fast and accurate positioning,the vibrat ion of the flexible manipulator is well restrained,and the high frequency jitter is suppressed.It achieves a good control effect.Finally,the experimental platform for vibration suppression of flexible manipulator is designed.The control effects of various control algorithms are tested on the platform.By analyzing the test results,the advantages and disadvantages ofvarious control methods for the positioning control and vibration suppression of flexible manipulator are obtained.