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Bi-Behavioral Prosthetic Knee Enabled by a Metamorphic Compliant Mechanism

  • Shannon Zirbel
  • Shane Curtis
  • Rachel Bradshaw
  • Luke Duffield
  • Greg Teichert
  • Nicholas Williams
  • Ron Rorrer
  • Spencer Magleby
  • Larry Howell
Conference paper

Abstract

Metamorphic mechanisms with two distinct behaviors were designed using compliant mechanism theory with a potential application as a prosthetic knee. The mechanism has discrete “locking” points to restrict rotation when under a compressive load. The designs use cross-axis flexural pivots, either in inversion or isolation, with engaging teeth to carry loads at distinct angles. Inverted compliant mechanisms function by inverting the mechanism so the compliant members are in tension when a compressive load is applied. Compliant mechanisms in isolation provide an alternative loading pattern which redirects the load to a passive rest. The mechanism incorporates teeth which engage during weight-bearing in flexion at up to 60° of flexion to lock the mechanism. When tension is applied to the device, the teeth are disengaged and the mechanism is allowed to rotate freely. The purpose of this design is to hold compressive loads both when un-flexed and flexed. The concept is applied in the preliminary design of a prosthetic knee joint. Proof-of-concept prototypes successfully demonstrate the metamorphic behavior.

Keywords

Compliant mechanisms Compression joint Prosthetic knee Cross-axis flexural pivot Weight-bearing in flexion 

Notes

Acknowledgements

The authors gratefully acknowledge the support of BYU faculty members Matt Seeley, Mark Colton, and Anton Bowden for their insightful feedback in design reviews. We also express our appreciation to Lane Ferrin of Northwest Orthotics and Dale Price for their collaboration on this project.

References

  1. 1.
    Guerinot AE, Magleby SP, Howell LL (2004) Preliminary design concepts for compliant mechanism prosthetic knee joints. Proceedings of ASME DETC, Salt Lake CityGoogle Scholar
  2. 2.
    Dai J, Jones JR (2005) Matrix representation of topological changes in metamorphic mechanisms. J Mech Des 127:837–840CrossRefGoogle Scholar
  3. 3.
    Dai J, Jones JR (1999) Mobility in metamorphic mechanisms of foldable/erectable kinds. J Mech Des 121:375–382CrossRefGoogle Scholar
  4. 4.
    Kandel ER, Schwartz JH, Jessell TJ (2000) Principles of neural science, 4th edn. McGraw-Hill, New YorkGoogle Scholar
  5. 5.
    Wilson AB (1968) Recent advances in above-knee prosthetics. Artif Limbs 12:1–27Google Scholar
  6. 6.
    Radcliffe CW (1977) Above-knee prosthetics. Knud-Jansen Lecture, New YorkGoogle Scholar
  7. 7.
    Patil KM, Chakraborty JK (1991) Analysis of a new polycentric above-knee prosthesis with a pneumatic swing phase control. J Biomech 24:223–233CrossRefGoogle Scholar
  8. 8.
    Johansson JL, Sherrill DM, Riley PO et al (2005) A clinical comparison of variable-damping and mechanically passive prosthetic knee devices. Am J Phys Med Rehab 84:563–575CrossRefGoogle Scholar
  9. 9.
    Howell LL (2001) Compliant mechanisms. Wiley, New YorkGoogle Scholar
  10. 10.
    Guerinot AE, Magleby SP, Howell LL, Todd RH (2005) Compliant joint design principles for high compressive load situations. J Mech Des 127:774–781CrossRefGoogle Scholar
  11. 11.
    Mankame ND, Ananthasuresh GK (2002) Contact aided compliant mechanisms: concept and preliminaries. Proceedings of ASME DETC conference, Montreal, Canada, pp 109–121Google Scholar
  12. 12.
    Jensen BD, Howell LL (2002) The modeling of cross-axis flexural pivots. Mech Mach Theory 37:461–476zbMATHCrossRefGoogle Scholar
  13. 13.
    Xu P, Jingjun Y, Guanghua Z (2010) An effective pseudo-rigid-body method for beam-based compliant mechanisms. Precis Eng 34:634–639CrossRefGoogle Scholar
  14. 14.
    Hongzhe Z, Shusheng B (2010) Stiffness and stress characteristics of the generalized crossspring pivot. Mech Mach Theory 45:378–391zbMATHCrossRefGoogle Scholar
  15. 15.
    Whittle MW (2007) Gait analysis: an introduction, 4th edn. Butterworth-Heinemann, OxfordGoogle Scholar

Copyright information

© Springer-Verlag London 2012

Authors and Affiliations

  • Shannon Zirbel
    • 1
  • Shane Curtis
    • 1
  • Rachel Bradshaw
    • 1
  • Luke Duffield
    • 1
  • Greg Teichert
    • 1
  • Nicholas Williams
    • 2
  • Ron Rorrer
    • 2
  • Spencer Magleby
    • 1
  • Larry Howell
    • 1
  1. 1.Brigham Young UniversityProvoUSA
  2. 2.University of Colorado DenverDenverUSA

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