Screen Printed Piezoceramic Actuators/Sensors Microfabricated on Organic Films and Stretchable Networks

Integration, deployment, and installation of SHM network hardware remains a significant challenge inhibiting fielding of SHM systems. SHM systems typically consist of sparse arrays of numerous transducers and large scale wiring in order to span target structures. These systems are currently assembled, one piece at a time, and installed by hand leading to significant labor costs. Because of the size and weight of the components they adversely affect and are parasitic to the host structure. This is particularly detrimental to high performance aerospace structures. Microfabricated stretchable sensor networks have received a lot of interest recently and have the potential to overcome these issues. These systems leverage nonstandard C-MOS processing techniques to mass fabricate micro and nano-scale device in a single integrated system. The complete system of devices with interconnecting wires is then expanded to span an area orders of magnitude greater than the original fabrication area. The result is a complete integrated network of numerous of small scale devices that will have minimal parasitic effects on a host structure and can be installed monolithically over large areas. However, fabrication limitations previously restricted the types of systems that could be created on these networks to passive, resistive devices like resistive temperature sensors and wiring. This paper presents an overview of recent research that has enabled the mass fabrication and deployment of screen printed piezoceramic transducers on organic stretchable network substrates including fabrication, deployment, and testing. Ultrasonic signals typical to SHM were actuated and detected as were strain waves from impacts. Results indicate that the screen printed piezoceramic transducers released and deployed on an organic substrate produce similar signal amplitudes as a baseline sample as printed on a silicon substrate. This work enables the mass fabrication and deployment of large arrays of microfabricated sensors, applicable to ultrasonic damage detection systems, on stretchable networks. This has the potential to revolutionize structural health monitoring by simplifying fabrication, installation and reducing the parasitic effects on host structures like added weight or volume.