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US-12624478-B2 - Tensile jamming fibers

US12624478B2US 12624478 B2US12624478 B2US 12624478B2US-12624478-B2

Abstract

The present invention relates to fiber jamming systems capable of tuning tensile stiffness of soft systems within seconds without the use of high voltage or temperature changes. The systems employ segmented fibrils of interspersed segments of stretchable and non-stretchable materials. Applying a vacuum to the fibrils in an enclosed volume elicits a large interfacial shear resistance to tensile displacement. In the absence of a vacuum, the fibrils are free to stretch and bend in any direction.

Inventors

  • Bilige Yang
  • Robert Baines
  • Xiaonan Huang
  • Rebecca Kramer-Bottiglio
  • Dylan Shah

Assignees

  • YALE UNIVERSITY

Dates

Publication Date
20260512
Application Date
20220930

Claims (20)

  1. 1 . A tensile jamming fiber, comprising: a length extending between a first end and a second end; at least a first and a second segmented elastic fibril, each extending between the first end and the second end and each comprising alternating segments of an elastic material and an inextensible material; and an elastic membrane enclosing the first and second segmented elastic fibrils in an interior space and forming an airtight and watertight housing; wherein the first and second segmented elastic fibrils are fused to the elastic membrane at the first end and the second end, and wherein segments of inextensible material in the first segmented elastic fibril partially overlap segments of inextensible material in the second segmented elastic fibril.
  2. 2 . The fiber of claim 1 , wherein the interior space of the elastic membrane is configured to support a vacuum.
  3. 3 . The fiber of claim 1 , wherein the elastic membrane comprises one or more ports fluidly connected to the interior space.
  4. 4 . The fiber of claim 1 , wherein the fiber comprises an unjammed state wherein the interior space of the elastic membrane comprises a positive pressure.
  5. 5 . The fiber of claim 4 , wherein the fiber comprises a jammed state wherein the interior space of the elastic membrane comprises a negative pressure, such that each of the segmented elastic fibrils are compressed together by the elastic membrane.
  6. 6 . The fiber of claim 5 , wherein the fiber in the unjammed state comprises an elasticity configured to permit stretching the length of the fiber by 200% or more.
  7. 7 . The fiber of claim 5 , wherein the fiber in the jammed state comprises an elasticity configured to permit little to no stretching of the length of the fiber.
  8. 8 . The fiber of claim 5 , wherein the fiber in the unjammed state comprises a first tensile stiffness that is lesser than a second tensile stiffness of the fiber in the jammed state.
  9. 9 . The fiber of claim 8 , wherein the second tensile stiffness is about 20× greater or more than the first tensile stiffness.
  10. 10 . The fiber of claim 5 , wherein the fiber in the unjammed state comprises a first bending stiffness that is substantially the same as a second bending stiffness of the fiber in the jammed state.
  11. 11 . The fiber of claim 5 , wherein the fiber is configured to switch between the unjammed state and the jammed state within a tenth of a second.
  12. 12 . The fiber of claim 1 , wherein the elastic material and the elastic membrane each comprise a material selected from the group consisting of: silicone rubber, neoprene rubber, nitrile rubber, and latex rubber.
  13. 13 . The fiber of claim 1 , wherein the inextensible material comprises a material selected from the group consisting of: polyester, nylon, acrylic, cotton, and carbon fiber.
  14. 14 . The fiber of claim 1 , wherein each segmented elastic fibril comprises a percentage of inextensible material relative to elastic material that is between about 50% and about 90%.
  15. 15 . A linear actuator device comprising a flexible cylindrical body and one or more fibers of claim 1 attached thereto.
  16. 16 . A planar actuator device comprising a flexible planar body and one or more fibers of claim 1 attached thereto.
  17. 17 . A method of fabricating a tensile jamming fiber, comprising the steps of: providing rectangular sections of a first sheet of a first elastic material; arranging the rectangular sections into at least two adjacent rows, wherein each row comprises regularly spaced rectangular sections having embedded segment lengths of an inextensible material in alignment, and adjacent rows are offset from each other such that rectangular sections of a first row at least partially overlap rectangular sections of a second row; coating the arranged rectangular sections in a second elastic material to form a second sheet; cutting the second sheet into fibers, wherein each fiber comprises a single row of regularly spaced embedded segment lengths of inextensible material in alignment; bundling at least two fibers in an elastic membrane, wherein the single row of regularly spaced embedded segment lengths of inextensible material in each fiber is offset from each other; and sealing the elastic membrane with the at least two fibers at their respective opposing ends to form an airtight and watertight interior space in the elastic membrane.
  18. 18 . The method of claim 17 , wherein the step of providing rectangular sections of a first sheet of a first elastic material includes embedding lengths of an inextensible material in parallel in the sheet of the first elastic material.
  19. 19 . The method of claim 18 , further comprising cutting the first sheet of the first elastic material into rectangular sections such that the embedded lengths of inextensible material in each rectangular section are cut to a desired segment length.
  20. 20 . The method of claim 17 , wherein the inextensible material comprises a material selected from the group consisting of: polyester, nylon, acrylic, cotton, and carbon fiber, and wherein the first elastic material, second elastic material, and elastic membrane each comprise a material selected from the group consisting of: silicone rubber, neoprene rubber, nitrile rubber, and latex rubber.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a U.S. national phase application filed under 35 U.S.C. § 371 claiming benefit to International Patent Application No. PCT/US2022/077370, filed Sep. 30, 2022, which is entitled to priority of U.S. provisional application No. 63/250,402 filed on Sep. 30, 2021, the contents of which are each incorporated by reference herein in their entirety. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT This invention was made with government support under Grant Nos. 1830870 and 1333468 awarded by the National Science Foundation. The government has certain rights in the invention. BACKGROUND OF THE INVENTION Biological organisms are able to adjust their anatomical structures, stiffness, and behaviors to accommodate a variety of tasks and environmental demands (Shah D et al., Advanced Materials. 2021 May, 33 (19): 2002882). Octopus tentacles, for example, can access nearly infinite trajectories, yet also form joint-like structures to adapt articulated limb control strategies for precise point-to-point movements (Sumbre G et al., Nature. 2005 February; 433 (7026): 595-6; Sumbre G et al., Current Biology. 2006 Apr. 18; 16 (8): 767-72). Caterpillars undulate and engage in inchworm gaits but can rapidly curl into a wheel form and propel themselves away from predators (Brackenbury J, Nature. 1997 December; 390 (6659): 453; Brackenbury J, Journal of insect physiology. 1999 Jun. 1; 45 (6): 525-33). Rapid reconfiguration capabilities make a body versatile; they are a hallmark of biological systems that thrive in the natural, unstructured world. Yet these capabilities have long eluded conventional robots, which are limited by rigid structures and discrete joints. To extend reconfiguration capabilities to artificial systems, researchers have leveraged continuously deformable materials to create soft robot bodies and actuators. Commonly, multiple actuators are patterned into a soft robot body, and a subset of those actuators is activated to achieve a desired body configuration (Tadokoro S et al., Twelfth IEEE International Conference on Micro Electro Mechanical Systems (Cat. No. 99CH36291) 1999 Jan. 21 (pp. 37-42); Hawkes E et al., Proceedings of the National Academy of Sciences. 2010 Jul. 13; 107 (28): 12441-5; Nguyen C T et al., Sensors and Actuators A: Physical. 2017 Nov. 1; 267:505-16; Zhou J et al., IEEE Robotics and Automation Letters. 2018 Jun. 28; 3 (4): 3379-86; Shah D S et al., IEEE Robotics and Automation Letters. 2019 Feb. 27; 4 (2): 2204-11). For example, several works have presented 3-degree-of-freedom (DOF) actuator modules containing three pneumatic actuators evenly spaced in a cylindrical configuration (Suzumori K et al., IEEE Control systems magazine. 1992 February; 12 (1): 21-7; Shih B et al., 2017 IEEE/RSJ international conference on intelligent robots and systems (IROS) 2017 Sep. 24 (pp. 494-501); Robertson M A et al., Science Robotics. 2017 Aug. 30; 2 (9); Martinez R V et al., Advanced materials. 2013 Jan. 11; 25 (2): 205-12; Xie R et al., 2018 IEEE International Conference on Robotics and Biomimetics (ROBIO) 2018 Dec. 12 (pp. 618-623)). These pneumatic multi-actuator systems are capable of bending in various directions, yet multiple chambers take up significant radial space and make miniaturizing such systems difficult for applications like minimally invasive surgery, where a smaller outer diameter is desired (Elsayed Y et al., Soft Robotics. 2014 Dec. 1; 1 (4): 255-62; Runciman M et al., Soft robotics. 2019 Aug. 1; 6 (4): 423-43). As an alternative to multi-chamber actuators, a single volumetrically expanding soft body can achieve controlled and complex motion when coupled with thin strain-limiting components (like woven meshes or fibers) that bias deformation in a programmed way (Galloway K C et al., 2013 16th International Conference on Advanced Robotics (ICAR) 2013 Nov. 25 (pp. 1-6); Sun Y et al., 2013 IEEE/RSJ International Conference on Intelligent Robots and Systems 2013 Nov. 3 (pp. 4446-4453); Deimel R et al., The International Journal of Robotics Research. 2016 January; 35 (1-3): 161-85; Connolly F et al., Proceedings of the National Academy of Sciences. 2017 Jan. 3; 114 (1): 51-6). Several recent studies have attempted to create inflatable soft actuators with re-programmable strain-limiting layers, thereby enabling a single actuator to attain multiple trajectories by controlling material properties at the actuator surface. One approach employed reconfigurable tensile strain-limiting adhesive patches that can be manually repositioned over the soft body to direct inflation (Kim S Y et al., Nature communications. 2019 Aug. 1; 10 (1): 1-8). Other approaches relied on thermally-responsive materials, such as low-melting point-alloy (LMPA) particulate composites (Buckner T L et al., Advanced Functional Materials. 2019 December; 29 (50): 1903368; Tonazzini A et al., Advanced Materials. 2016 December; 28 (46): 10142-8) and shape memory