| Ferroelectric ceramics material is capable of producing a strain on its surface in response to a high-energy light. It can be used as actuators or sensors by laminating on the space beam, plate and shell or embedding inside the structure to realize the active control of the shape of the structure. Photostrictive actuators with many advantages over the those actuators which activated by electric or magnetic signals(piezoelectric actuators, electrostrictive actuators, SMA actuators.etc.),such as no hard-wired connection, remote control, and immunity from electric and magnetic disturbances. It is very suitable for applying a non-contact excitation and control in the space environment and conform to the lightweight trend. In this paper, the research of constitutive model of photostrictive actuator, mechanics model of photostrictive beam structure and optimization problem of morphing structures based on different polarized photostrictive actuators are studied.The ferrodielectric ceramic material and the optical-electric-mechanical-thermal coupling effect of photostrictive actuator are first expounded in this paper. Analytical models is derived with surface bonded 0-1 and 0-3 polarized photostrictive optical actuators and an finite element model is established based on enhanced assumed strain and assumed natural strain methods to improve the element’s performance. Numerical simulation result show the proposed method and the finite element model are robust and effective.A general optimization system is designed for flexible structure by using finite element software and genetic algorithm based on the UMAT subroutine of photostrictive actuators.The displacement of morphing wing is chosen as objective function and the position and the number of photostrictive optical actuators are taken as design parameters in this optimization system. Numerical simulation results verify the optimization method can realize the displacement optimization of morphing wing structure. |
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