Theory And Experiment Research On Vibration Active Control For Elastic Linkage Mechanisms

In this dissertation, the theory and experiment research on vibration active control for elastic linkage mechanisms are carried out. The dynamic modeling of elastic linkage mechanisms including smart components, vibration active control methods, effects of crank speed changing upon dynamic characteristic of mechanisms and some related difficult issues are thoroughly studied. The main research work is as follows:Dynamic equations for elastic four-bar linkages mechanism are derived using the finite element method and Lagrange Equation and solved. In the established dynamic model, the coupling effects between elastic deformation and rigid body motion of mechanism, between the piezoelectric components and the dynamic and potential energy, and the geometrical non-linear effects due to deformation of linkage are considered. The modified state-space-closed method is adopted for solving these non-linear differential equations with time-variant coefficents. The calculated dynamic responses of elastic four-bar linkages are agreement to the experiment results.A model algorithmic control (MAC) strategy based on discrete state-space equations of linkage mechanisms is proposed for the active control of elastic vibration. The main advantage of MAC strategy lies in no strict requirement for the sysment model and its adaptability to uncertain factors of system. This makes it suitable for vibration control of elastic linkage mechanism involving complicated influence factors. The simulation and experiment investigation are carried out using the proposed method to control vibration responses of an elastic four-bar linkage. The simulation results are compaired with that of optimal control law. It indicates that the results of MAC method are better. Experiment research validates the feasibility of the proposed strategy.On basis of the investagetion of MAC strategy, a predictive functional control (PFC) algorithm is introduced into the vibration active control for elastic four-bar linkage. Reference trace followed by vibration response of mechanism, base functions and voltage constrain conditions are selected according to...