Optimal Placement And Vibration Control Of Intelligent Cantilever Beam

A intelligent structure can be defined as a structure or structure component with bonded or embedded sensors and actuators as well as an associated control system, which enables the structure to respond simultaneously to external stimuli exerted on it and then suppresses undesired effects or enhance desired effects. It involves multi-discipline knowledge, such as materials science, mechanical engineering, control theory, and computer science. The performance requirements of future space structures, jet fighters and concept automobiles have brought much interest to the area of smart structures.A cantilever beam with smart materials is study in this paper. Firstly, by the piezoelectric material's positive piezoelectric effect and negative piezoelectric effect, the sensing and actuating abilities are articularly analyzed in this paper, and gained the sensing and actuating equations espectively. This paper analyses the interaction between piezoelectric materials film and the vibration system of piezoelectric smart cantilever beam, the dynamical model and close-loop control state equation are established with regard to some pairs of piezoelectric materials sensors and actuators. The independent modal space control technique which is based on a negative velocity feedback control law is put forth, and the control unit is designed. At last, the emulational example in this paper has proved the validity of the method. The influence of piezoelectric materials film's position and length and it's thinness to the control performance is studied, they explain the interaction between these parameters, and help to the design of active vibration control system of piezoelectric smart cantilever beam. Based on the maximum deformation theory, a effective sensor and actuator placement for energy dissipation is proposed. This thesis also took the minimum stored energy algorithm in which the actuator locations and feedback gain were taken as design variables as the objective function in terms of control cost and control effect.Particle swarm optimization (PSO) is an optimization algorithm based on swarm intelligence developed by Kennedy and Eberhart in 1995. The particles warm algorithm finds out the optimal regions in complex search space through the interaction of individuals in a population of particles. What makes PSO predominant is that it is easy to calculate, simple to imply and can be used widely in many field. This paper combined the particle swarm optimization (PSO) algorithm, presented the optimal actuator placements and feedback gain.At last, the validity of active vibration control for intelligent structure is demonstraled by means of the computer simulation. And some significant conclusions and results are obtained.