| 1. | The buckling analysis of functionally gradient thin elastic plate bonded piezoelectric patches 压电元件驱动的功能梯度弹性薄板的屈曲 |
| 2. | The dynamic model of the section - varying intelligent piezoelectric beams with surface - bonded piezoelectric element is developed and the natural frequencies are analyzed 建立变截面智能压电梁的动态模型,分析表面粘贴压电元件的均质梁的固有频率。 |
| 3. | To discretely distributed sensor / actuator units , on the premise of stable control , different localization of them would lead to different effect of vibration control 对于离散分布的压电元件来讲,在控制器稳定的前提下,不同位置的传感作动单元将产生不同的控制效果。 |
| 4. | It combines finite element method and the optimal design of piezoelectric elements together , and therefore can be applied to the vibration analysis and design of complex smart structures 改进后的方法将结构数值分析方法与压电元件的优化配置问题相结合,更加具有可操作性。 |
| 5. | It is shown that the effects of the stiffness and inertia of the piezoelectric element that lead to higher first natural frequency on the natural frequencies of the beam are significant , and that of the elastic modulus of the bonding layer is small 研究表明,压电元件的刚度和惯量对梁的频率影响很大,变截面智能压电梁的一阶固有频率总是高于等截面梁的固有频率。 |
| 6. | This study adopts active detection technique based on lamb wave to monitor damage in composite materials . pzt ceramics with the diameter of 8mm are bonded on the surface of fiberglass - reinforced composite material acting as both actuators and sensors to generate and collect lamb waves . the waves emitted interact with discontinuities and experience a change in their propagation characteristics when damage is generated 本文采用lamb波主动监测技术,利用粘贴在复合材料板表面的压电元件,通过选择恰当的激励信号,激励出可进行lamb波分析的主动监测信号,进而对监测信号进行分析及模式处理,初步实现了二维结构的损伤定位。 |
| 7. | Then , it deals with the theory of the finite element , experimental modal analysis and hilbert huang transform , which forms the theoretical groundwork of the following experimental investigation aiming at analyzing the effect of the transducer debonging on the dynamic response of composite laminated cantilever beam 再次,采用压电元件做传感器的复合材料悬臂梁结构为试验对象,利用模态分析、 hht变换的方法,对压电元件与复合材料之间的脱胶损伤对结构动态特性的影响进行试验研究。 |
| 8. | Piezoelectric elements can be used as sensors and induced strain actuators in active vibration control systems . since the positioning of piezoelectric elements can affect control performance greatly , it has to be carefully determined , in this dissertation , detailed theoretical analysis and brief experimental study is made on the optimal positioning of piezoelectric elements for active vibration control applications 在智能结构振动主动控制系统中,压电元件可以分别作为传感器和作动器,其在结构中的布置方式对振动控制性能影响很大,是振动主动控制系统设计的重要问题。 |
| 9. | According to the principles of piezoelectric smart concrete structure health monitoring , a mathematic model of monitor system for static performances is discussed . then , the virtual waveform generator based on dds is designed using a data acquisition card and a pc to supply multiform excitation signals to piezoelectric elements in experiment . the theoretical analysis and experimental research demonstrate the performances of the waveform generated by the virtual instrument 为了给压电元件提供多种类型的激励信号,根据直接数字合成原理,设计了利用数据采集卡和计算机实现dds波形发生的虚拟仪器,并对生成波形的各方面性能进行了理论分析和实验研究,从理论和实验两个方面分析了这种波形发生方式所能取得的效果。 |
| 10. | Based on the requirements of high precision pointing / targeting of advanced spacecraft , dynamic modeling of spacecraft with flexible appendages bonded with piezoelectric sensors / actuators , attitude control and active vibration suppression theory are studied deeply in this dissertation , which is funded by the research fund for the doctoral program of higher education of china item ? “ large flexible multi - bodies structure spacecraft active vibration control technology ” ( 20050213010 ) . the main contents of this dissertation are as the follows : an approximate analytical dynamic model of a flexible spacecraft with surface bonded piezoelectric sensors and actuators is derived using hamilton ’ s principle with discretization by the assumed mode method . the model is then converted to state - space form for the purpose of control design 本学位论文结合高等学校博士学科点专项科研基金“挠性多体结构卫星主动振动控制技术研究” ( 20050213010 )课题,从理论上对粘贴有压电智能元件的挠性航天器的建模、姿态控制和主动振动控制理论等展开了深入的研究,其研究内容主要包括以下几个方面:利用hamilton原理推导了挠性航天器的动力学模型、压电元件的作动方程及检测方程,并采用模态分析方法,进一步将挠性航天器的耦合方程规范化,使之适应于姿态控制系统的分析和设计。 |