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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Additive manufacturing as a tool for high-throughput experimentation
Additive manufacturing (AM) is a disruptive technology with a unique capability in fabricating parts with complex geometry and fixing broken supply chains. However, many AM techniques are complicated with their processing features due to complex heating and cooling cycles with the melting of feedstock materials. Therefore, it is quite challenging to directly apply the materials design and processing optimization method used for conventional manufacturing to AM techniques. In this viewpoint paper, we discuss some of the ongoing efforts of high-throughput (HT) experimentation, which can be used for materials development and processing design. Particularly, we focus on the beam- and powder-based AM techniques since these methods have demonstrated success in HT experimentation. In addition, we propose new opportunities to apply AM techniques as the materials informatic tools contributing to materials genome.
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- Award ID(s):
- 2047218
- NSF-PAR ID:
- 10401933
- Date Published:
- Journal Name:
- Journal of Materials Informatics
- Volume:
- 2
- Issue:
- 3
- ISSN:
- 2770-372X
- Page Range / eLocation ID:
- 12
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.20517/jmi.2022.19
