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Thin, flexible sheets can be patterned and bonded to form internal fluidic networks, which enable actuation, sensing, and control, but failure of these sheet-based systems—and how to take advantage of this failure—remains relatively unexplored. Here, we examine this concept using heat-sealable textiles as a material platform. We determine the effects of geometry and material processing on bond strength and burst pressure; these findings can ensure a sheet-based fluidic system is sufficiently robust for a given use case. Building on this framework, we introduce a fuse-like component into which failure is deliberately programmed. In addition to limiting damage in the case of overpressurization, we leverage this programmed failure to enable distinct capabilities including (1) the binary selection of operating modes and (2) the sequencing of a series of tasks with a single pressure input. These findings will facilitate the development of more intelligent sheet-based fluidic systems.
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SOFT ROBOTICS: FLUID-DRIVEN SELF-FOLDING PAPERS
We demonstrate a self-folding paper robot with capillary force driven fluid. When water is sprayed on fluidic channels patterned on paper, the 2-D sheet of paper can be controllably self-folded into various 3-D structures; half-oval, circle, round-edge square, triangle, half-circle, and table. The self-folding paper sheet can be readily fabricated via a double-sided wax printing method, forming a bilayer structure of the fluidic channel and the hydrophobic wax, in which these two layers have different swelling/shrinking properties. The patterned paper performs folding actuation with water and unfolding behavior with evaporation without being mechanically manipulated by external forces or moments. Finally, we create a paper gripper based on this self-folding actuation, conveying a low-weight object. This report demonstrates the possibility of paper microfluidics for self-folding actuation and soft robotics.
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- Award ID(s):
- 1503462
- PAR ID:
- 10377142
- Date Published:
- Journal Name:
- Technical digest SolidState Sensor Actuator and Microsystems Workshop
- ISSN:
- 1539-204X
- Page Range / eLocation ID:
- 163-166
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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