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Structural fiber-reinforced polymer (FRP) composite materials consisting of a polymer matrix reinforced with layers of high-strength fibers are used in numerous applications, including but not limited to spacecraft, vehicles, buildings, and bridges. Researchers in the past few decades have suggested the necessary integration of sensors (e.g., fiber optic sensors) in polymer composites to enable health monitoring of composites’ performance over their service lives. This work introduces an innovative cognizant composite that can self-sense, compute, and implement decisions based on sensed values. It is a critical step towards smart, resilient infrastructure. We describe a method to fabricate textile sensors with flexible circuitry and a microcontroller within the polymer composite, enabling computational operations to take place in the composite without impacting its integrity. A microstructural investigation of the sensors showed that the amount of oxidative agent and soaking time of the fabric play a major role in the adsorption of polypyrrole (PPy) on fiberglass (FG). XPS results showed that the 10 g ferric chloride solution with 6 h of soaking time had the highest degree of protonation (28%) and, therefore, higher adsorption of PPy on FG. A strain range of 30% was achieved by examining different circuitry and sensor designs for their resistance and strain resolution under mechanical loading. A microcontroller was added to the circuit and then embedded within a composite material. This composite system was tested under flexural loading to demonstrate its self-sensing, computing, and actuation capabilities. The resulting cognizant composite demonstrated the ability to read resistance values and measure strain using the embedded microcontroller and autonomously actuate an LED light when the strain exceeds a predefined limit of 2000 µε. The application of the proposed FRP system would provide in situ monitoring of structural composite components with autonomous response capabilities, as well as reduce manufacturing, production, and maintenance costs.

Speculative design, as a diverse set of methods that aim to offer critique, can be challenging to engage productively. In this design case, we share how a prior, stalled design project--an ambitious vision of interdisciplinary design education partnered with business and housing development projects in Santa Fe, New Mexico--provided compelling precedent as we sought to reframe during the COVID-19 pandemic. We recognized that solution-focused ways of working in the prior project left the design problem undefined. As we began the design work detailed in this case, we leveraged the perspectives and design knowledge of our interdisciplinary team of faculty and students. While design cases often emphasize the designed training or program, we focus on our reframing process, sharing vignettes as we prepared to and participated in activities at a design workshop, and then used our own design practices to engage in problem framing workshops. In sharing these accounts, we characterize the pandemic as a trickster and speculative co-designer, who revealed much about how our efforts were entangled with institutional structures. Across these punctuated vignettes of design work, we highlight how an initial broad problem frame invited this trickster to participate and how the application of problem framing tools wrested framing agency from the trickster. Collectively, this anchored our attention to systemic inequities in ways that troubled notions of sustainability.