Vibration Reduction Analysis And Trajectory Tracking Control Of Manipulator

With the development of intelligence manufacturing,industrial robots,as a high technology product with advantages of intelligence and precision,have assumed an increasingly important position in the field of industrial automation technology.Series manipulator is one of the most widely used industrial robots.During the operation of the manipulator,the problem of end precision has always been the focus of research.The main factors affecting the end precision include manufacturing errors?assembly error and the vibration of the manipulator.According to the source of vibration,the vibration of the manipulator can be divided into two categories: one is the vibration problem between the base of the manipulator and the ground,and the other is the deformation vibration caused by the force on each member of the manipulator.Both kinds of vibration affect the precision of the manipulator.In order to improve the accuracy during the operation of manipulator,the vibration is studied in this paper.The details of this article are as follows:(1)By analyzing the research status and development trend of industrial robots,the China's research situation of industrial robots,the vibration significance of the research on robot arm is obtained.Thus,the research direction of this paper is proposed.(2)Firstly,the basic knowledge of kinematics and dynamics of the robot is simply introduced,and then a simplified model of three degrees of freedom mechanical rigid arm with load is established.Secondly,taking advantage of Newton-Euler dynamic method to analysis the model's dynamics,solving the mechanical arm model and finding each link's relationship of force and moment balance.Finally,solving the manipulator's force with respect to the base.(3)Taking the base as the research object,the spring and damped vibration models are established in the spatial coordinate system of three degrees of freedom.According to the vibration model,the vibration parameter equations of the base are solved in the spatial coordinate system.Based on the vibration parameter equation,this paper studies the vibration characteristics of the base during the operation of the manipulator.Then proposing measures to reduce the vibration amplitude,setting the parameter value,and using MATLAB to observe the change situation of vibration amplitude.(4)The simplified model of the two degrees of freedom flexible rod with load manipulator is established.The radial and axial deformation of the flexible rod is regarded as the vibration of the flexible rod.Considering the energy generated by the deformation of the flexible rod,the sliding mode control algorithm was used for MATLAB simulation to research the trajectory tracking in the case of vibration.The results show that the new combined dynamics equation has it's feasibility.(5)Analyzing and studying the neural network control algorithm,then giving the Lagrange dynamics equation of the manipulator,and conducting simulation using robot adaptive control algorithm based on RBF neural network compensation to verificate the manipulator's trajectory tracking control.The results show that the reduction of vibration amplitude of the manipulator's base can be realized by two ways.One way is choosing different damp factor and spring factor have different reducing vibration effect.Another way is to adjust the value of the link's mass and the position of the center of mass of the manipulator.When considering manipulator's arm is flexible rod,regarding vibration as the deformation of rob's radial and axial direction changed with time,then using sliding mode control algorithm to simulation.The results show that control moment changed with time in this hypothetical case,providing a reference for the control torque under vibration condition.Taking advantage of the neural network control algorithm,designing the Lyapunov function,observing the tracking situation of manipulator's end,the feasibility of this algorithm is verificated.