Research And Optimization Of Strong Nonlinear Dynamic Characteristics Of Photostriction Material Controller

Traditional piezoelectric materials and magnetostrictive materials have good self-adaptive ability,but because they need the relationship between peripheral wires and auxiliary equipment,they inevitably have electromagnetic interference.Compared with traditional smart materials,photostrictive materials only need a specific light source to drive,which enables photostrictive materials to reduce unnecessary electromagnetic interference.Therefore,photostrictive materials have good application prospects in aerospace active control structures.Lanthanum modified lead zirconate titanate ceramics(PbLaZrTi,abbreviated as PLZT)is a typical and widely used photostrictive material.At present,the dynamics research of PLZT materials mainly focuses on weak nonlinear theory,and ignores the random interference problem of light source.In this paper,the combination of theory,numerical simulation and finite element simulation is used to carry out strong nonlinear dynamic analysis and optimization design of PLZT composite structure.The main research contents can be divided into the following aspects:1)Through the study of the previous constitutive model of PLZT wafers,we found that the light intensity can be regarded as a constant,and then the constitutive model can be constructed by using the nonlinear function expression of the electric field and independent variables.On this basis,the constitutive relation of the PLZT wafer based on the van-der-Pol hysteresis model is established,and it is simulated.The comparison with the experimental data shows that the constitutive model established in this paper can be better It reflects the constitutive relationship between electric field and strain,temperature-electric field-strain,and stress-strain of PLZT wafer.2)By solving the PLZT composite beam model,the dynamic response equation of the cantilever beam structure is obtained.Using the multi-scale method to solve the dynamic response equation,the general solutions of the system under autonomous and non-autonomous conditions are obtained,and the stability of the system is further discussed.The obtained conclusions provide a certain theoretical basis for the practical application of the PLZT wafer lamination mechanism.3)Considering the inevitable random interference of the emitted light source,the dynamic equations of the PLZT wafer composite beam model and the PLZT composite plate model under random excitation are established.Then,the system is solved by the stochastic averaging method and the energy function averaging method,the Fokker-Planck-Kolmogorov(FPK)equation of the system is obtained,and the critical condition of the stochastic Hopf bifurcation is studied.Finally,the effects of the length and width of the PLZT wafer on the perturbation of the free end of the PLZT composite were simulated using finite element simulation software.The simulation results show that for the cantilever beam system in this paper,the coverage rate of 10% is the best;for the cantilever plate system in this paper,the coverage rate of the length direction is 10%,and the coverage rate of the width direction is 50%.