【作者】 姜晶；

【导师】 邹鸿生；

【作者基本信息】 哈尔滨工业大学 ， 机械设计及理论， 2013， 博士

【摘要】 将智能材料作为传感器及作动器，层合于空间板壳结构表面或嵌入其内部，实现对结构的智能控制已经成为航空、航天领域的一个重要发展方向。与传统的作动器（如压电作动器、记忆合金作动器及电致伸缩作动器等）相比，当采用基于光电材料镧改性锆钛酸铅（PLZT）的光控作动器时，由于作动器与控制光源间无需线路连接，因此可以避免电磁干扰，并且符合航空、航天结构轻质化发展的趋势，具有重大的理论研究价值。本文将开展利用光控作动器的板壳结构振动控制的研究，提出利用沿厚度（0-3）方向极化的PLZT（简称PLZT（0-3））作动器及光控压电混合驱动两种方式实现板壳结构的振动控制，针对光控作动器产生驱动应变的本构模型、光电层合板壳结构系统动力学建模、面向不同应用背景的分布式光控作动器的构型设计及光控作动器的激励策略等问题展开系统的研究，为此类智能结构在航空航天领域的具体应用提供理论依据。分别建立了PLZT（0-3）作动器及光控压电混合驱动方式的本构方程。基于PLZT在光－电－热－力等多能场耦合作用下的反常光生伏打效应及光致伸缩机理，研究光照强度及PLZT（0-3）作动器的尺寸参数对其产生的饱和光致应变及时间常数的影响，从而建立了PLZT（0-3）作动器在光照阶段产生驱动应变的数学模型；提出了利用PLZT在紫外光照射下产生的光电压驱动压电作动器的光控压电混合驱动方式，利用等效电路模型，建立了光控压电混合驱动下作动器产生应变的本构方程；通过实验证明了所建立的数学模型能准确描述在不同光强下，光控作动器产生的驱动应变随光照时间的动态响应。基于Hamilton原理和多层薄壳理论，建立了可适用于不同结构类型、不同几何参数的光控层合板壳结构的通用动力学模型；基于所建立的动力学模型，利用模态展开技术建立了光控层合板壳结构的模态控制方程及分布式光控作动器在激励信号的作用下，对结构产生的模态控制力数学模型。为研究作动器布局及构型设计奠定理论基础。基于作动器边界条件的的变化，开展了能产生多自由度非均匀控制力/力矩的新型光致伸缩作动器构型的研究。基于平面位移变分法，建立了特定边界条件下，作动器在激励信号的作用下对结构产生的非均匀控制力及力矩的分布函数；以开口圆柱壳为例，利用模态控制因子，参数评价了新型作动器的尺寸、布局对其产生模态控制行为的影响；针对PLZT（0-3）光致伸缩作动器“单向驱动性”的特点，提出了对新型作动器各区域的速度反馈半周期激励的控制策略；利用Newmark-β法对开口圆柱壳的模态控制方程进行数值仿真分析，仿真结果证明了本文所提出的控制策略的有效性，并且表明增大光照强度可以提高作动器的响应速度，从而改善新型作动器对结构的模态控制效果。研究表面成型式作动器构型，以实现对结构的光控独立模态控制。针对典型结构，推导了实现结构独立模态控制的光控作动器表面电极形状函数；以悬臂梁结构为例，分别研究了基于PLZT（0-3）作动器及光控压电混合驱动，实现结构的独立模态控制。针对PLZT（0-3）作动器，提出了作动器各个区域双面粘贴，两个光源ON/OFF的激励策略；针对光控压电混合驱动，提出了多片PLZT与压电作动器正/反接控制的激励策略；结合速度反馈定光强控制的控制算法，分别对两种光控方式下悬臂梁的独立模态控制进行了数值仿真分析，仿真结果证明了针对光控板壳结构独立模态控制，作动器表面电极形状函数设计及控制策略的正确性。对光控压电混合驱动的激励策略及光控结构独立模态主动控制进行实验研究。针对光控压电混合驱动提出四种激励策略，并对其可行性进行了实验分析；搭建了实验平台，对模态传感器的正交模态性进行了实验验证；通过对不同光照强度下悬臂梁独立模态主动控制的实验研究，有力地支撑了本文关于成型式传感/作动器的理论推导及参数评价的相关结论。更多还原

【Abstract】 Smart materials can be used as sensors and actuators by laminating on orinserting in space plate and shell structures to realize Smart control, which has beenan important direction in the aerospace field. In contrast to traditional actuators(e.g.,piezoelectric actuators, SMA actuators, electrostrictive actuators.etc.), photostrictiveactuators or actuators actuated by hybrid photovoltaic/piezoelectric actuationmechanism does not require hard-wird connections to control light source. Thus, thecontrol commands will not be influenced by undesirable electric noises. Withoutaccessorial devices and connecting wires, photonic control which conforms to thelightweight trend of space structure has great research value. In this paper, twomethods which are the lanthanum modified lead zirconate titanate (PLZT) with0-3polarization photostrictive laminated smart structure and hybridphtovoltaic/piezoelectric actuation mechanism are proposed respectively to realizevibration control of shell structures. Systematical theoretical research on theestablishment of constitutive model of photostrictive actuator, dynamic model of thephotostrictive laminated plate and shell, actuator configuration theory and controlscheme of actuator are carried out. This research can provide theoretical proof forapplications of this kind of smart structure in the field of space aviation.Constitutive equations defining the photo-induced time dependent strains ofactuator for the two photonic control method are established respectively. In view oflight-electric-thermal-elastic coupling, the photovoltaic effect and photostrictivemechanism of PLZT are studied. Equations are established to define the effect ofgeometric parameters of0-3polarized PLZT (PLZT(0-3)) acuator and light intensityon photo-induced saturated strain and time constant. Constitutive equations definingthe time history response of photo-induced strain for PLZT(0-3) actuator areaccordingly established. The novel hybrid photovoltaic/piezoelectric actuationmechanism is proposed. The ultraviolet light-driven PLZT induced voltages are usedto drive piezoelectric actuator. Based on the equivalent electrical model, equationsare derived to define the actuation strain of piezoelectric acutuator driven byphotovoltage. These two constitutive model are verified by experimentsrespectively.Based on the Hamilton’s principle and composite shell theory, the systematicdynamic model of the photostrictive laminated shell are set up, which can be appliedto shell with different structure types and geometric parameters. Based on the modalexpansion technique, the modal control actions of photostrictive actuator are st udied,which can technically support the design of actuator location and configuration. By specifically configuring the boundary condition of the actuator, askew-quad actuator system inducing multi-DOF non-uniform control forces andcontrol moments is proposed. Based on the variation method, the distributionfunctions of induced forces and moments are calculated. In the case study of opencylindrical shell, control actions of the skew-quad actuator system with differentlocations and sizes are calculated to define the better placement and the size of thenew actuator system. According to the characteristic of one-way actuation of PLZT（0-3） photostrictive actuator, the control schemes of half cycle illumination toeach region of skew-quad actuator system together with the constant light intensitycontrol based on velocity feedback is proposed. Based on the Newmark-β method,the modal control equation is numerically analyzed, and the results show that theshell vibration can be effectively controlled by this proposed control scheme. Thesimulation results of different light intensity show that the increase of light intensitywill increase the response speed of PLZT(0-3) actuator which accordingly improvethe control effectiveness of shell structures.In order to realize photonic independent modal control of smart structure, theshaped orthogonal actuator theory is studied. Electrode shape functions of theactuators are disigned for some typical structures. Independent modal control of thecantilever beam based on the PLZT(0-3) photostrictive actuator and on the hybridphotonic/piezoelectric actuation mechanism is studied respectively. According to thecharacteristic of one-way actuation of PLZT(0-3) photostrictive actuator, theactuation strategy of double side ON/OFF actuation with two light sources for eachregion of shaped orthogonal photostrictive actuator is proposed. In order to realizethe independent modal control of cantilever beam using hybridphotovoltaic/piezoelectric actuation mechanism, orthogonal sensors are designed.The ON/OFF control of positive/negative connection between PLZT andpiezoelectric actuator is used, combining with constant light control algorithm basedon velocity feedback. Dynamic modal control equations of the cantilever beamlaminated with orthogonal actuators based on the two photonic control methods arenumerically simulated respectively. The simulation results show that the orthogonalsensors/actuators designed and control schemes proposed for the two photonicmethod can effectively realize photonic independent modal control of cantileverbeam.Experiments for the actuation srategies of hybrid photovoltaic/piezoelectricactuation mechanism and active independent modal control of beam are carried out.Four actuation srategies are proposed and their feasibility are tested. Experimentalplatform for active beam independent modal control is set up, and the modalorthogonality of orthogonal sensors is tested. The validity of theoretical derivationand evaluation results of shaped photostrictive actuator configuration theory can be verified by the experimental results of different light intensity.更多还原