Research On Nonlinear Robust Control Of Flexible Manipulator With Base Vibration Based On Singular Perturbation Method

Ammunition transfer manipulator,as the core component of automatic loading system for artillery ammunition,the accuracy of positioning control and loading time will directly affect the performance of the whole weapon system.At present,the main problems that restrict the development of ammunition automatic loading system are: vibration interference caused by Complex pavement condition and recoil;dynamic contact impact caused by excessive structural rigidity;and low load weight ratio.Therefore,In order to improve the performance of the ammunition transmission manipulator,in this paper,flexible joints and flexible link are introduced into the model,then,we discussed the modeling process and control theory of flexible Ammunition transfer manipulator with base vibration.The main work of this article includes:(1)This dissertation introduces the structure and working principle of the ammunition transmission manipulator,and analyzes the influence of the chassis vibration on the system.The vibration types are divided into three types: vertical vibration,pitching vibration and sway vibration.According to three types of base vibration modes,the dynamic equations of the ammunition transmission manipulator are established.The three dynamic models are transformed into a unified foem to analyze the effects of different vibrations on the system.(2)The position control and flexible vibration suppression of ammunition transfer manipulator under vibration base considering flexible joints and flexible link characteristics are studied.Flexible joint and flexible link are simplified to linear spring and Euler-Bernoulli beam,respectively.For two different flexible systems,the vibration of the base is regarded as an external uncertain disturbance,and we establishe the coupling models of flexible ammunition transmission manipulator with base vibration.Using the singularly perturbed technique,the system is reduced to two subsystems,namely,slow subsystem and fast subsystem.The slow subsystem represents the rigid motion of the manipulator and the low-frequency vibration of the base;the fast subsystem represents flexible motion and the high-frequency vibration of base.In this regard,a robust nonsingular terminal sliding mode neural network controller and LQR controller are designed for flexible link manipulator.A robust controller based on neural network and a velocity differential feedback controller are designed for flexible joint manipulator.The simulation results show that the designed hybrid controller can not only overcome the disturbance of base vibration,but also achieve precise position control of the manipulator and suppress the flexible vibration rapidly(3)The flexible joint and flexible link are introduces into the ammunition transmission manipulator mounted on vibration bases.The base vibration is regarded as the external uncertain disturbance,and the dynamic model of the vibration based composite flexible ammunition transmission manupulator is established.Through double-time scale technology,different vibration states are decomposed,and the whole system would be decomposed into three subsystems:rigid slow motion subsystem,flexible joint vibration subsystem and flexible manipulator vibration subsystem.Aiming at the slow motion,robust controller based on neural network is designed.Aiming at the slow motion,LQR controller and velocity differential feedback controller were designed.The simulation shows that the hybrid controller can compensate the vibration of the base,achieves precise positioning control and suppressed two kinds of flexible vibrations at the same time.