Session: SYMP S-1: Integrated Systems

Paper Number: 141360

141360 - Embedded Fluidic Control in Compliant 2-D Architectures 

The emerging field of soft robotics has simultaneously reshaped traditional robotics applications and introduced new use cases for robots by incorporating soft materials [1]. The vast majority of soft robotics research, though, has targeted actuation and sensing, with control schemes often relying on bulky, rigid electronic infrastructure and precluding intrinsically responsive behavior [2]. Accordingly, researchers have recently developed fluidic controllers in 3D soft elastomeric architectures [3], starting from fluidic analogs to resistors and transistors [4-5], building to fluidic circuits and oscillators [6-7], and finally achieving functionally complete fluidic digital logic controllers [8-9]. These 3D fluidic controllers remain limited, however, in their ability to readily interface with the 2D sheet-based textile architectures characteristic of wearable robots.

 

We address this limitation by embedding fluidic digital logic in a fully textile sheet-based architecture that accepts user input, stores data in memory, and actuates pneumatic devices for mobility assistance based on built-in Boolean logic [10]. Our textile logic modules are flexible and lightweight, can be integrated in regular clothing, withstand tens of thousands of actuation cycles, are robust against washing and rough handling, and can be cascaded successively to implement a wide array of logic functions. We demonstrate the monolithic fabrication of integrated logic circuits—comprising multiple pneumatic inputs, outputs, logic elements, and interconnections—from stacked textile sheets using a scalable and cost-effective process. Finally, we extend this approach to both hybrid digital-analog control and pure analog control by implementing variable sheet-based fluidic resistors composed of compliant microporous open-cell foams.

 

These logic-enabled textiles have the potential to enable future generations of comfortable, low cost, and electronics-free wearable robots for assisting the nearly one billion people worldwide currently living with disabilities. Ongoing work focuses on integration of onboard sources of power [11], miniaturization of fluidic circuitry while retaining high performance, and translation to consumers through scalable manufacturing.

 

References

[1] P. Rothemund, Y. Kim, R.H. Heisser, X. Zhao, R.F. Shepherd, C. Keplinger, "Shaping the Future of Robotics through Materials Innovation," Nature Materials, 20(12), 2021.

[2] B. Jumet, M.D. Bell, V. Sanchez, D.J. Preston, "A Data-Driven Review of Soft Robotics," Advanced Intelligent Systems, 4(4), 2022.

[3] A. Rajappan, B. Jumet, D.J. Preston, "Pneumatic Soft Robots Take a Step Toward Autonomy," Science Robotics, 6(51), 2021.

[4] P. Rothemund, A. Ainla, L. Belding, D.J. Preston, S. Kurihara, Z. Suo, G.M. Whitesides, "A Soft, Bistable Valve for Autonomous Control of Soft Actuators," Science Robotics, 3(16), 2018.

[5] J.D. Hubbard, R. Acevedo, K.M. Edwards, A.T. Alsharhan, Z. Wen, J. Landry, K. Wang, S. Schaffer, R.D. Sochol, "Fully 3D-printed Soft Robots with Integrated Fluidic Circuitry," Science Advances, 7(29), 2021.

[6] D.J. Preston, H.J. Jiang, V. Sanchez, P. Rothemund, J. Rawson, M.P. Nemitz, W.-K. Lee, Z. Suo, C.J. Walsh, G.M. Whitesides, "A Soft Ring Oscillator," Science Robotics, 4(31), 2019.

[7] D. Drotman, S. Jadhav, D. Sharp, C. Chan, M.T. Tolley, "Electronics-free Pneumatic Circuits for Controlling Soft-legged Robots," Science Robotics, 6(51), 2021.

[8] D.J. Preston, P. Rothemund, H.J. Jiang, M.P. Nemitz, J. Rawson, Z. Suo, G.M. Whitesides, "Digital Logic for Soft Devices," Proceedings of the National Academy of Sciences (PNAS), 116(16), 2019.

[9] C.J. Decker, H.J. Jiang, M.P. Nemitz, S.E. Root, A. Rajappan, J.T. Alvarez, J.A Tracz, L. Wille, D.J. Preston, G.M. Whitesides, "Programmable Soft Valves for Digital and Analog Control," Proceedings of the National Academy of Sciences (PNAS), 119(40), 2022. 

[10] A. Rajappan, B. Jumet, R.A. Shveda, C.J. Decker, Z. Liu, T.F. Yap, V. Sanchez, D.J. Preston, "Logic-Enabled Textiles," Proceedings of the National Academy of Sciences (PNAS), 119(35), 2022.

[11] R.A. Shveda, A. Rajappan, T.F. Yap, Z. Liu, M.D. Bell, B. Jumet, V. Sanchez, D.J. Preston, "A Wearable Textile-Based Pneumatic Energy Harvesting System for Assistive Robotics," Science Advances, 8(34), 2022.

Presenting Author: Daniel Preston Rice University

Presenting Author Biography: Dr. Daniel J. Preston directs the Preston Innovation Laboratory at Rice University conducting research at the intersection of energy, materials, and fluids. He is a recipient of the NSF CAREER Award, the ASME Old Guard Early Career Award, and the Energy Polymer Group Certificate of Excellence. His group’s recent work has been published in PNAS, Science Advances, Science Robotics, Nano Letters, and Advanced Science. His lab is funded by NASA, the National Science Foundation, and the Department of Energy, among other sources. Dr. Preston earned his B.S. (2012) in mechanical engineering from the University of Alabama and his M.S. (2014) and Ph.D. (2017) in mechanical engineering from the Massachusetts Institute of Technology. Following his graduate degrees, he trained as a postdoctoral fellow from 2017–2019 at Harvard University in the Department of Chemistry and Chemical Biology prior to joining Rice University as an assistant professor in July 2019.

Authors:

Daniel Preston