Research On Rigid Flexible Coupling Dynamics Theoretical Of Elastic Beams In Large Overall Rotation

With the development of science and technology,mechanical systems in the fields of spacecraft,robot and other engineering begin to develop in the direction of light weight,high speed and high precision.Therefore,the rigid flexible coupling system with flexible components has been applied,and the research on rigid flexible coupling dynamics theoretical of elastic beams in large overall rotating has sprung up.However,most of the dynamic models are only suitable for low-speed,and lack of the rigid flexible coupling dynamic model which can accurately reflect the actual motion of the system at high-speed.In order to realize high-speed and high-precision control of flexible mechanism in large overall rotating,this paper studies the dynamic modeling of elastic beams in large overall rotating.On the basis of the established model,the coupling relationship between the parameters and the vibration characteristics of the system is studied,which provides important data support for reducing the vibration of the system itself and improving the control accuracy of the system.The main research contents of this paper are as follows:(1)The large overall rotating elastic beams was assumed to be Euler-Bernoulli beam.Then,the rigid-flexible coupling dynamic model of the elastic beam was built based on Galerkin method and Hamilton principle of minimum action.Based on this,the friction of the driving motor is included.The traditional dynamics model,the rigid-flexible coupling dynamics model and the rigid-flexible coupling dynamics model considering the output torque and friction of the motor are established.(2)Based on the MATLAB platform,the vibration characteristics of the elastic beam under three different models are analyzed.The effects of the elastic beam center-line deformation and the motor friction on the vibration characteristics of the system are explained.The accuracy of the established model is verified.(3)The coupling relationship between the structural parameters of the elastic beam and the dynamic performance is analyzed.It provides data support for the optimal design of elastic beam length and radius at different specific speeds.The coupling relationship between output torque,coulomb friction,static friction,viscous friction coefficient of the motor and vibration characteristics at different speeds is studied.(4)The research results show that: the output torque of the motor has a greater impact on the vibration characteristics of the system,and the higher the speed,the more obvious it is.Coulomb friction has effect on the system vibration characteristics at low speeds,but its effect also increases as the speed increases.The coefficient of viscous friction has a great influence on the vibration characteristics of the system,and has a linear coupling relationship with the system amplitude.The static friction has a small effect on the vibration characteristics.