Research On Chatter Suppression Strategy Of Rigid And Flexible Connectors

In the field of human-machine compatibility,robots are required to have the characteristics of combining rigidity and flexibility.The introduction of flexible arms and elastic joints is accompanied by a series of problems such as decreased positioning accuracy and end flutter.For complex rigid flexible connectors,this article introduces three vibration suppression strategies:feedback control,feedforward control,and hybrid control,establishes quantitative evaluation indicators for vibration suppression,and achieves rapid vibration suppression during the motion process.The research content includes the description of elastic deformation of the flexible arm,and the establishment and derivation of dynamic models for rigid flexible connectors;Research on vibration suppression of linear quadratic form optimal control optimized by genetic algorithm;Research on joint trajectory planning and vibration suppression for particle swarm optimization;Optimization analysis of piezoelectric actuator configuration and negative feedback experimental research,etc.The main work and research content are as follows.(1)Dynamic modeling of rigid-flexible connectors.Based on the vibration displacement during the motion process of the flexible robotic arm,drawing on the Euler Bernoulli beam theory,applying mechanical vibration,Newton’s laws of mechanics,and relevant knowledge of material mechanics,the motion equation of the transverse vibration of the flexible beam model is established,and the natural frequency and main mode function are determined.The accuracy of the elastic deformation description of the flexible arm is verified using ANSYS modal analysis method.The dynamic equations of rigid flexible connections are established using the assumed mode method and Lagrange method,providing a basis for the design of vibration controllers and simulation experimental research.(2)Research on flutter suppression method for optimal control of linear quadratic type.Using feedback control,according to the optimal control principle of linear quadratic type,the state space expression of rigid-flexible connectors is solved by performance index function and Riccati differential equation,and the influence of weighted matrix diagonal parameter value on the control effect is explored.The genetic algorithm is used to optimize the diagonal parameters of the weighted matrix,and three vibration suppression evaluation indexes are established,MATLAB numerical simulation and chatter suppression evaluation index results show that the linear quadratic form optimal control can achieve good vibration suppression effect,and the linear quadratic form optimal control optimized by genetic algorithm has better vibration suppression effect.(3)Research on tremor inhibition method for joint trajectory planning.Using feedforward control,based on the characteristics and constraints of joint trajectory planning,a fifth degree polynomial function,a cycloid function,and a sine trapezoidal basis function are selected to construct a flexible arm trajectory planning function for rigid flexible connections.The law of the influence of different joint angular velocities on control effectiveness is explored.The particle swarm optimization algorithm is used to optimize the sine trapezoidal basis function and find an optimal vibration suppression trajectory.The simulation results show that the interpolation of the sine trapezoidal basis function optimized by the particle swarm algorithm can better attenuate the vibration displacement of the flexible arm during motion,achieving good vibration suppression effects.(4)Active vibration control and experimental research with additional piezoelectric actuators.Elaborate on the working principle of piezoelectric actuators,combined with optimization analysis of piezoelectric actuator configuration,nine control schemes were designed,including passive control,active control,and active passive hybrid control.Based on the concept of vibration detection and closed-loop negative feedback real-time control,a closed-loop experimental device is constructed that integrates flexible robotic arms,real-time data acquisition,data processing,and controlled driving components.The negative feedback control program is developed using Lab VIEW software,achieving functions such as closed-loop synchronous control of vibration suppression,real-time recording of piezoelectric actuator reverse vibration,vibration displacement,and automatic generation of data curves.The highlights and characteristics of the research work are reflected in ANSYS modal analysis,numerical method solutions,analytical solutions,and model accuracy verification;Genetic algorithm optimizes the selection of linear quadratic form optimal control parameters,and particle swarm optimization optimizes the parameters of sine trapezoid basis function;The construction of a closed-loop experimental device that integrates flexible robotic arms,real-time data acquisition,data processing,and controlled driving components.