Project 9
Attaching Microdevices to Fibers for Soft and Breathable Electronics
(Prof. Cindy harnett, ECE)
Above: Springy MEMS pop-ups released under a woven fabric grip onto fiber bundles (bundle diameter: 100 microns). Fabricated in the University of Louisville REU program.
This REU student will work at the boundary of microfabrication and textile engineering toward electronics on soft surfaces. It’s not only about putting wearable displays on your shirt! Breathable circuit boards will put electronics in new places: cell-growth scaffolds, air handling filters, coolant-flushed systems, and other locations where fluids need to flow through and around sensors.
Three grippers in parallel, powering light-emitting diodes from wires. Both examples were fabricated by previous REU students on this project.
Our previous REUs successfully attached microdevices to conductive fibers [1,2]. Now we’re thinking about a key difference between a rigid circuit board and a conductive fiber mesh: the mesh can wrinkle and distort, making it great for wearables and soft robotics applications, but tricky to align with other circuits and connectors when building a system. The specific goal for this summer is for the REU to create a fiber that blocks “wrong way” electrical signals using diodes. We have already achieved an alignment-free contact grid in previous work using a diode array on a conventional printed circuit board that does not bend or stretch [3]. You will be trained to attach these small components and evaluate the mechanical and electrical properties of the resulting fibers. Beyond technical experience, the REU students on this project will gain professional experience as they work alongside other research staff and students in the cleanroom and the Harnett lab (www.harnettlab.org). Each REU in the lab has co-authored a research paper and one is a co-inventor on a pending patent.
References
[1] Challa, Sushmita, Canisha Ternival, Shafquatul Islam, Jasmin Beharic, and Cindy K Harnett. 2019. “Transferring Microelectromechanical Devices to Breathable Fabric Carriers with Strain-Engineered Grippers.” MRS Advances, February 2019, pp. 1–8.
[2] Islam, M. S., S. Challa, M. H. Yassin, S. S. Vankayala, J. Beharic, and C. K. Harnett. "MEMS Bimorph Fiber-Gripping Actuators." In 2022 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), pp. 1-6. IEEE, 2022.
[3] Harnett, C. K. "Tobiko: A Contact Array for Self-Configuring, Surface-Powered Sensors." In Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems, pp. 2024-2028
