Prosthetic foot with tunable performance

• US 8,070,829 B2
• Filed: 04/01/2005
• Issued: 12/06/2011
• Est. Priority Date: 09/30/2003
• Status: Expired due to Fees

• Current Assignee: BioQuest Prosthetics LLC
• Original Assignee: BioQuest Prosthetics LLC
• Inventors: Townsend, Barry W., Claudino, Byron K.
• Primary Examiner(s): Willse, David H
• Assistant Examiner(s): BLANCO, JAVIER G
• Application Number:
  US10/594,796
• Publication Number:
  US 20070213840A1
• Time in Patent Office: 2,440 Days
• Field of Search: 623 47- 55
• US Class Current: 623/55
• CPC Class Codes: A61F 2/60 Artificial legs or feet or parts thereof
• CPC Class Codes: A61F 2/6607 Ankle joints
• CPC Class Codes: A61F 2/70 electrical
• CPC Class Codes: A61F 2/74 fluid , i.e. hydraulic or pneumatic
• CPC Class Codes: A61F 2/741 using powered actuators, e.g. stepper motors or solenoids
• CPC Class Codes: A61F 2/748 Valve systems
• CPC Class Codes: A61F 2/76 Means for assembling, fitting or testing prostheses, e.g. for measuring or balancing, e.g. alignment means
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/5009 having two or more elastomeric blocks
• CPC Class Codes: A61F 2002/501 having an inflatable pocket filled with fluid, i.e. liquid or gas
• CPC Class Codes: A61F 2002/502 for adjusting length
• CPC Class Codes: A61F 2002/5023 along two perpendicular axes
• CPC Class Codes: A61F 2002/503 for adjusting elasticity, flexibility, spring rate or mechanical tension
• CPC Class Codes: A61F 2002/5066 Muscles
• CPC Class Codes: A61F 2002/5079 Leaf springs A61F2002/6657 takes precedence
• CPC Class Codes: A61F 2002/5083 modular
• CPC Class Codes: A61F 2002/607 Lower legs
• CPC Class Codes: A61F 2002/6621 Toes
• CPC Class Codes: A61F 2002/6635 Metatarsals
• CPC Class Codes: A61F 2002/6642 Heels
• CPC Class Codes: A61F 2002/6685 : S-shaped
• CPC Class Codes: A61F 2002/701 : operated by electrically controlled means, e.g. solenoids or torque motors
• CPC Class Codes: A61F 2002/704 : computer-controlled, e.g. robotic control
• CPC Class Codes: A61F 2002/7695 : Means for testing non-implantable prostheses
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws

Abstract

A resilient lower extremity prosthesis comprising a foot, an ankle and a shank above the ankle is provided with an artificial muscle on the shank of the prosthesis for storing energy during force loading of the prosthesis in the active propulsion phase of a person'"'"'s gait and in the later stages of stance-phase of gait releasing the stored energy to aid propulsion of the person'"'"'s trailing limb and body.

Claims

1. A prosthetic foot comprising:

a foot keel extending in a longitudinal direction;

a resilient ankle;

an elongated, upstanding, resilient calf shank above the ankle;

wherein the ankle and calf shank are monolithically formed as a continuous resilient member, the shank extending upward in a substantially anterior facing convexly curvilinear manner over at least most of the height of the shank above the ankle, the ankle being anterior facing convexly curved and extending upwardly anteriorly from a lower portion of the ankle secured to the foot keel and extending posteriorly to a lower end of the resilient member, the resilient member flexing in the longitudinal direction during gait for storing and releasing energy to improve dynamic response of the prosthetic foot in gait;

at least one artificial muscle provided on at least one of the foot, ankle and shank of the prosthetic foot for storing energy during force loading of the prosthetic foot in the active propulsion phase of a person'"'"'s gait and in the later stages of stance-phase of gait releasing said energy to aid propulsion of the person'"'"'s trailing limb and body;

wherein said at least one artificial muscle includes an artificial muscle extending between an upper portion of the calf shank and a lower part of the prosthetic foot.

2. The prosthetic foot according to claim 1, wherein said at least one artificial muscle is preloaded in tension to increase the potential energy of the prosthetic foot.

3. The prosthetic foot according to claim 1, further comprising means for adjusting the energy storage capacity of the prosthetic foot by adjustably preloading the at least one artificial muscle in tension.

4. The prosthetic foot according to claim 3, wherein said means for adjusting is selected from the group consisting of a cam, a pad and a bladder containing pressurized fluid.

5. The prosthetic foot according to claim 1, wherein said at least one artificial muscle includes an artificial muscle on the foot keel of the prosthetic foot.

6. The prosthetic foot according to claim 5, wherein said artificial muscle on the foot keel connects plantar posterior and anterior portions of the foot keel.

7. The prosthetic foot according to claim 5, including a foot shell over the lower extremity of the prosthetic foot and said artificial muscle on the foot keel connects plantar posterior and anterior portions of the foot shell.

8. The prosthetic foot according to claim 1, including an artificial muscle which extends between and connects the prosthetic foot and a socket on a leg stump of a person'"'"'s body when the prosthetic foot is in use.

9. The prosthetic foot according to claim 1, wherein said at least one artificial muscle is provided on said resilient member.

10. The prosthetic foot according to claim 1, wherein an artificial muscle provided on said foot.

11. The prosthetic foot according to claim 1, wherein said at least one artificial muscle is formed at least in part of a viscoelastic material selected from the group consisting of rubber and polymer.

12. The prosthetic foot according to claim 1, further comprising a detector for detecting a force exerted by the prosthetic foot during said force loading of the prosthetic foot, and means responsive to the detected force for adjusting the energy storage capacity of the at least one artificial muscle during said force loading as a function of the detected force.

13. The prosthetic foot according to claim 1, wherein said at least one artificial muscle has a wider cross sectional area at an intermediate portion along the length of the muscle.

14. The prosthetic foot according to claim 1, wherein said at least one artificial muscle is formed at least part of an electroactive polymer-based artificial muscle.