Study of advanced integrated piezoelectric sensor systems for the evaluation of structures and materials

用于评估结构和材料的先进集成压电传感器系统的研究

• 批准号: RGPIN-2014-06448
• 负责人: Wang, Xiaodong
• 金额: $ 1.75万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=567809
• 关键词: Study; advanced; integrated; piezoelectric; sensor

Developing compact, sensitive, durable, inexpensive real-time sensors for mechanical measurements represents a significant engineering challenge and has received considerable attention from research and industrial communities. Among the commonly used sensors, piezoelectric sensors are often the most attractive, which offer the highest power density and the relative ease of application. Their high electromechanical coupling and almost instantaneous response time enable the effective conversion of mechanical measurements into electric signals with a relatively high sensitivity and high resolution. Piezoelectric sensors are currently used in various engineering applications, such as the nondestructive evaluation of structures to detect cracks and damage, the characterization of the mechanical property of thin films to determine their thickness and modulus, and the chemical and biological surface-acoustic-wave devices to identify chemical and biological species, to name a few. Major impediments to the wider application of piezoelectric sensors are (i) the limitation by their minimum detectable stress, and (ii) the difficulty in integrating signals from multiple sensors. Existing techniques based on individual piezoelectric sensors can only be used in situations where a very limited number of parameters need to be determined. This results in major difficulties in quantitative nondestructive evaluation of structures containing embedded damage and in the detection of multiple chemical and biological species in surface-acoustic-wave devices. It is, therefore, the objective of the current project to study highly sensitive integrated piezoelectric sensors and develop an imaging technique for the quantitative evaluation of structural integrity. To develop highly sensitive sensors, study of metamaterial-based piezoelectric sensors will be conducted. Metamaterials refer to new types of composites exhibiting exceptional properties not commonly observed. The new piezoelectric sensors will be composites containing carefully designed local structures, from which high sensitivity can be achieved through the internal interaction between them. For damage imaging, by integrating signals from multiple piezoelectric sensors, the wave propagation near the sensors can be regenerated and studied. An inverse process based on the signals from the multiple sensors will then be established to quantitatively identify the anomalies, which have disturbed the wave propagation. Both theoretical and experimental studies will be conducted. The main steps of the research include: (i) Developing a unified and fundamental dynamic model of interacting piezoelectric elements, in forms of fibres and sheets, under different loading and boundary conditions, (ii) Using the developed model to evaluate the behaviour of new piezoelectric sensors with designed local structures, which form interacting piezoelectric elements, and study the relation between the sensitivity of the sensors and the arrangements of the local structures, (iii) Studying sensor response to different embedded anomalies, and developing an inverse technique to quantitatively identify embedded defects, (iv) Conducting experimental studies for verifying the theoretical predictions, evaluating new sensor designs and studying integrated multiple sensors for quantitative imaging of damage. The proposed study will significantly improve the understanding and provide important knowledge for the design of piezoelectric sensors. The project also represents a new topic in nondestructive evaluation and other related areas. Its feasibility has been clearly shown from our recent research results. In the long term, the outcome of the research can be used in the design of next generation piezoelectric sensors.

开发紧凑、灵敏、耐用、廉价的机械测量实时传感器是一项重大的工程挑战，已经受到了研究和工业界的广泛关注。在常用的传感器中，压电传感器往往是最具吸引力的，因为它具有最高的功率密度和相对容易的应用。它们的高机电耦合和几乎瞬时的响应时间使得机械测量有效地转换为具有相对高灵敏度和高分辨率的电信号。压电传感器目前用于各种工程应用，例如无损评价结构以检测裂纹和损伤，表征薄膜的力学性能以确定其厚度和模量，以及化学和生物表面声波装置以识别化学和生物物种，仅举几例。压电传感器广泛应用的主要障碍是：(i)其最小可检测应力的限制，以及（ii）难以整合来自多个传感器的信号。现有的基于单个压电传感器的技术只能用于需要确定非常有限数量的参数的情况。这导致了对含有嵌入损伤的结构进行定量无损评估以及在表面声波装置中检测多种化学和生物物种的主要困难。因此，当前项目的目标是研究高灵敏度集成压电传感器，并开发一种用于结构完整性定量评估的成像技术。为了开发高灵敏度的传感器，将进行基于超材料的压电传感器的研究。超材料指的是新型复合材料，它们表现出不常见的特殊性能。新的压电传感器将是包含精心设计的局部结构的复合材料，通过它们之间的内部相互作用可以实现高灵敏度。对于损伤成像，通过对多个压电传感器的信号进行积分，可以对传感器附近的波传播进行再生和研究。然后建立一个基于多个传感器信号的逆过程，以定量识别干扰波传播的异常。将进行理论和实验研究。研究的主要步骤包括：(1)建立了在不同载荷和边界条件下纤维和片状相互作用的压电元件的统一和基本的动力学模型；(2)利用所建立的模型来评估具有设计的局部结构的新型压电传感器的行为，这些局部结构形成相互作用的压电元件，并研究传感器的灵敏度与局部结构布置之间的关系；（iii）研究传感器对不同嵌入异常的响应，并开发一种反演技术来定量识别嵌入缺陷；（iv）进行实验研究以验证理论预测，评估新的传感器设计，研究集成多传感器的损伤定量成像。本文的研究将大大提高对压电传感器的理解，并为压电传感器的设计提供重要的知识。该项目也为无损评估及其他相关领域开辟了一个新课题。我们最近的研究结果清楚地表明了它的可行性。从长远来看，该研究成果可用于下一代压电传感器的设计。