Significant progress into the development and use of stretchable sensors for structural health monitoring (SHM) has been made in the last several years. The fusion of stretchable, adaptable sensing materials with highly specialized additive manufacturing techniques allows for the development of highly adaptive, customizable, and easily accessible sensing solutions. However, a significant portion of these works explore SHM topics at a macro level, and with a reduced focus on implementation. As such, little application or experimentation into practical sensing elements, especially those at the micro scale, have followed the advances in sensing technology. In this work, we demonstrate the application of recent developments in stretchable electronics, alongside multiple advanced additive manufacturing processes, to develop a novel flexible microscale sensor. A complex sensor is designed and printed utilizing Digital Light Processing (DLP) to directly fabricate the structure. The printed sensor is then filled with a piezoresistive sensing element of either PEDOT:PSS or carbon-based PDMS (cPDMS), which provided strain readings via resistance change. After being filled with a sensing mixture, the sensor is shown to operate as desired under large deformations. Additionally, the sensor is shown to work effectively when embedded into a separate additively manufactured part. A flexible test coupon is manufactured using the DLP AM process, and a microsensor is embedded inside the coupon structure. This sensing systems is tested in both tension and bending. These results show the feasibility of implementing both modern day AM processes and into current structural health monitoring developments into practical applications.
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This content will become publicly available on June 9, 2024
Roadmap on measurement technologies for next generation structural health monitoring systems
Abstract Structural health monitoring (SHM) is the automation of the condition assessment process of an engineered system. When applied to geometrically large components or structures, such as those found in civil and aerospace infrastructure and systems, a critical challenge is in designing the sensing solution that could yield actionable information. This is a difficult task to conduct cost-effectively, because of the large surfaces under consideration and the localized nature of typical defects and damages. There have been significant research efforts in empowering conventional measurement technologies for applications to SHM in order to improve performance of the condition assessment process. Yet, the field implementation of these SHM solutions is still in its infancy, attributable to various economic and technical challenges. The objective of this Roadmap publication is to discuss modern measurement technologies that were developed for SHM purposes, along with their associated challenges and opportunities, and to provide a path to research and development efforts that could yield impactful field applications. The Roadmap is organized into four sections: distributed embedded sensing systems, distributed surface sensing systems, multifunctional materials, and remote sensing. Recognizing that many measurement technologies may overlap between sections, we define distributed sensing solutions as those that involve or imply the utilization of numbers of sensors geometrically organized within (embedded) or over (surface) the monitored component or system. Multi-functional materials are sensing solutions that combine multiple capabilities, for example those also serving structural functions. Remote sensing are solutions that are contactless, for example cell phones, drones, and satellites. It also includes the notion of remotely controlled robots.
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- Award ID(s):
- 2038761
- NSF-PAR ID:
- 10466434
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Institute of Phisics (IOP)
- Date Published:
- Journal Name:
- Measurement Science and Technology
- Volume:
- 34
- Issue:
- 9
- ISSN:
- 0957-0233
- Page Range / eLocation ID:
- 093001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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