Prosthetic, orthotic, and other rehabilitative robotic assistive devices actuated by smart materials

• US 6,379,393 B1
• Filed: 09/14/1999
• Issued: 04/30/2002
• Est. Priority Date: 09/14/1998
• Status: Expired due to Fees

• Current Assignee: Rutgers University
• Original Assignee: Rutgers University
• Inventors: Mosley, Michael J., Pfeiffer, Charles, DeLaurentis, Kathryn J., Mavroidis, Constantinos
• Primary Examiner(s): Willse, David H.
• Assistant Examiner(s): STEWART, ALVIN J
• Application Number:
  US09/395,623
• Time in Patent Office: 959 Days
• Field of Search: 623/25, 623/24, 623/57, 623/58, 623/59, 623/60, 623/61, 623/63, 623/64, 623/66
• US Class Current: 623/25
• CPC Class Codes: A61F 2/54 Artificial arms or hands or parts thereof
• CPC Class Codes: A61F 2/581 Shoulder joints
• CPC Class Codes: A61F 2/582 Elbow joints
• CPC Class Codes: A61F 2/583 Hands; Wrist joints
• CPC Class Codes: A61F 2/585 Wrist joints
• CPC Class Codes: A61F 2/586 Fingers
• CPC Class Codes: A61F 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61F 2002/5039 allowing only for single rotation
• CPC Class Codes: A61F 2002/5043 with rotation-limiting stops, e.g. projections or recesses
• CPC Class Codes: A61F 2002/5066 Muscles implantable A61F2002/0894
• CPC Class Codes: A61F 2002/5093 Tendon- or ligament-replacing cables implantable A61F2/08
• CPC Class Codes: A61F 2002/5098 with rotation-limiting means
• CPC Class Codes: A61F 2002/543 Lower arms or forearms
• CPC Class Codes: A61F 2002/546 Upper arms
• CPC Class Codes: A61F 2002/587 Thumbs
• CPC Class Codes: A61F 2002/704 computer-controlled, e.g. robotic control
• CPC Class Codes: A61F 2002/7615 Measuring means for implanting artificial joints A61F2/4657
• CPC Class Codes: A61F 2002/7695 Means for testing non-implantable prostheses for testing implantable prostheses A61F2240/008; for implanting artificial joints A61F2/468
• CPC Class Codes: A61F 2210/0033 electrically, e.g. heated by resistor
• CPC Class Codes: A61F 2310/00047 Aluminium or Al-based alloys

Abstract

The present invention is directed to state-of-the-art medical devices using smart materials and related emerging technologies under development for robotics. In particular, the present invention is directed to the development of rehabilitative (i.e. prosthetic, orthotic, surgical) devices actuated by smart material artificial muscles to increase the dexterity and agility of an artificial limb or a dysfunctional body part, so that movement of the limb more accurately simulates movement of a human appendage. A kinetic assistive device is provided is provided which is constructed of a lightweight material (such as aluminum) and has a plurality of smart material actuators attached thereto. A system for detecting environmental stimulation of the device is provided in electrical communication with such actuators to effect movement of said device in response to detection signals produced thereby. The system includes a plurality of sensors, such as proximity detectors, accelerometers, tactile sensors and the like which are mounted on the assistive device and which provide data to computer-controlled command circuitry. This data can be encoded and used to control the movement of the assistive device via the actuators to more accurately predict the performance of the device in relation to that of an actual human limb.

Claims

1. A kinetic prosthesis actuated by artificial muscles providing increased dexterity and agility of an artificial limb, said prosthesis comprising:

an articulated support member releasably mounted to a patient in signal communication with said patient'"'"'s residual muscle and having a free end responsive to electromyographic signals communicated thereby, said support member having a plurality of artificial muscles attached thereto, said artificial muscles comprising smart materials; and

command circuitry in electrical communication with said residual muscles for communicating said electromyographic signals to said artificial muscles so as to effect anthropometrical movement of said articulated support member;

said artificial muscles being in electrical communication with said command circuitry such that when signals are transmitted to said command circuitry, said artificial muscles respond thereto for effecting movement of said articulated support.

2. The prosthesis of claim 1 wherein said artificial muscles comprise a bundle of elongate elements.

3. The prosthesis of claim 2 wherein said elements are selected from the group of artificial muscle configurations consisting of wires, ribbons, sheets and springs.

4. The prosthesis of claim 2 wherein said elements are mechanically connected in spaced parallel relation to one another.

5. The prosthesis of claim 4 wherein said elements are arranged electrically in a combination of series and parallel current paths.

6. The prosthesis of claim 1 wherein said artificial muscles are selected from the group of smart materials consisting of electrostrictive polymers, electroactive polymers, conductive polymers, electrostatic devices, piezoelectric polymers, mechano-chemical polymers and gels, shape memory polymers and shape memory alloys.

7. The prosthesis of claim 1 further comprising a detector system for detecting environmental stimuli sensed by said articulated support member and for producing detection signals in response thereto, and for transmitting said detection signals to said command circuitry through said artificial muscles.

8. The prosthesis of claim 7 wherein said system includes a plurality of sensors mounted on said articulated support member for detecting said environmental stimuli.

9. The prosthesis of claim 8 wherein said sensors are selected from the group of sensors consisting of force sensors, torque sensors, tactile sensors, thermal sensors, accelerometers and proximity detectors.

10. The prosthesis of claim 9 wherein said sensors produce detection signals corresponding to said environmental stimulation and transmit said detection signals to said command circuitry.

11. The prosthesis of claim 8 further comprising a portable device in electrical communication with said command circuitry.

12. The prosthesis of claim 11 wherein said portable device includes a belt wearable by said patient having a microcontroller therewithin for control of said member movement.

13. The prosthesis of claim 11 wherein said portable device includes circuitry for converting sensory inputs from said sensors into detection signals corresponding to said environmental stimulation.

14. The prosthesis of claim 1 wherein said articulated support member free end includes an anthropometrical element defined thereat.

15. The prosthesis of claim 14 wherein movement of said anthropometrical element is effected by said artificial muscles.

16. A method of effecting movement in an artificial limb wherein said limb is in signal communication with electromyographic signals obtained from a patient'"'"'s residual muscles, said method comprising the steps of:

providing an articulated support member releasably mounted to said patient in signal communication with said patient'"'"'s residual muscles, said member having at least one joint with a joint axis defined therethrough and further having a free end responsive to electromyographic signals communicated thereby;

attaching a plurality of artificial muscles comprising smart materials to said articulated support member so as to effect movement of said member corresponding to contraction or expansion of said artificial muscles; and

providing command circuitry in electrical communication with said residual muscles for communicating said electromyographic signals to said artificial muscles so as to effect said member movement;

said artificial muscles being in electrical communication with said command circuitry such that transmission of signals to said command circuitry effects movement of said member.

17. The method of claim 16 wherein said artificial muscles comprise a bundle of elongate elements.

18. The method of claim 17 wherein said elements are selected from the group of artificial muscle configurations consisting of wires, ribbons, sheets and springs.

19. The method of claim 17 further comprising the step of mechanically connecting said elements in spaced parallel relation to one another.

20. The method of claim 19 further comprising the step of arranging said elements electrically in a combination of series and parallel current paths.

21. The method of claim 20 further comprising the step of applying a voltage to said elements to effect a change in length thereof.

22. The method of claim 16 wherein said artificial muscles are selected from the group of smart materials consisting of electrostrictive polymers, electroactive polymers, conductive polymers, electrostatic devices, piezoelectric polymers, mechano-chemical polymers and gels, shape memory polymers and shape memory alloys.

23. The method of claim 16 further comprising the step of determining a fixed attachment point for said artificial muscles.

24. The method of claim 23 wherein said attachment step is effected proximate said joint axis to enable large angular movements of said member.

25. The method of claim 23 further comprising the step of folding at least one of said artificial muscles in an overlapping configuration along a length of said articulated support member.

26. The method of claim 16 further comprising the step of providing a system for detecting environmental stimulation of said articulated support member and producing corresponding detection signals in response thereto, and for transmitting said detection signals to said command circuitry.

27. The method of claim 26 wherein said system includes a plurality of sensors mounted on said articulated support member to detect environmental stimulation thereof.

28. The method of claim 27 wherein said sensors are selected from the group of sensors consisting of force sensors, torque sensors, tactile sensors, thermal sensors, accelerometers and proximity detectors.

29. The method of claim 27 wherein said sensors produce said detection signals to correspond to said environmental stimulation and transmit said detection signals to said command circuitry.

30. The method of claim 29 further comprising the step of providing a portable device in electrical communication with said command circuitry.

31. The method of claim 30 wherein said portable device includes a belt worn by said patient and having a microcontroller therewithin for controlling movement of said articulated support member.

32. The method of claim 30 wherein said portable device includes circuitry for converting sensory inputs from said sensors into said detection signals.

33. An assistive device actuated by artificial muscles which provides increased dexterity and agility of an artificial or dysfunctional limb, comprising:

an articulated member having at least one joint pivotable about a corresponding joint axis and having a plurality of artificial muscles comprising smart materials affixed thereto wherein said artificial muscles are in signal communication with a system of sensors mounted on said member, said sensors detecting environmental stimulation of said member and producing detection signals corresponding to said stimulation, said sensors further transmitting said detection signals to command circuitry in electrical communication with said artificial muscles so as to effect anthropometrical movement of said member in response thereto.

34. The device of claim 33 wherein said artificial muscles are fabricated from at least one bundle of elongate elements.

35. The device of claim 34 wherein said elements are selected from the group of artificial muscle configurations consisting of wires, ribbons, sheets and springs.

36. The device of claim 34 wherein said elements are mechanically connected in spaced parallel relation to one another between a pair of end plates.

37. The device claim 36 wherein said elements are arranged electrically in a combination of series and parallel current paths.

38. The device of claim 37 wherein a voltage is applied to said elements to effect a change in length thereof.

39. The device of claim 33 wherein said artificial muscles are selected from the group of smart materials consisting of electrostrictive polymers, electroactive polymers, conductive polymers, electrostatic devices, piezoelectric polymers, mechano-chemical polymers and gels, shape memory polymers and shape memory alloys.

40. The device of claim 33 wherein said artificial muscles are fixed proximate said joint axis to enable large angular movements of said member.

41. The device of claim 33 wherein at least one of said artificial muscles is folded in an overlapping configuration along a length of said member.

42. The device of claim 33 wherein said sensors are selected from the group of sensors consisting of force sensors, torque sensors, tactile sensors, thermal sensors, accelerometers and proximity detectors.

43. The device of claim 33 further comprising a portable device in electrical communication with said command circuitry.

44. The device of claim 43 wherein said portable device includes a belt worn by said patient and having a microcontroller therewithin for control of said member movement.

45. The device of claim 43 wherein said portable device includes circuitry for converting sensory inputs from said sensors into said detection signals.

46. A method of effecting movement in an artificial limb wherein said limb is in signal communication with electromyographic signals obtained from a patient'"'"'s residual muscles, said method comprising the steps of:

providing an articulated support member releasably mounted to said patient in signal communication with said patient'"'"'s residual muscles, said member having at least one joint with a joint axis defined therethrough and further having a free end responsive to electromyographic signals communicated thereby;

attaching a plurality of artificial muscles comprising smart materials to said articulated support member at a location proximate said joint axis so as to enable large angular movements of said member corresponding to contraction or expansion of said artificial muscles; and

providing command circuitry in electrical communication with said residual muscles for communicating said electromyographic signals to said artificial muscles so as to effect said member movement;

said artificial muscles being in electrical communication with said command circuitry such that transmission of signals to said command circuitry effects movement of said member.

47. The method of claim 46, wherein said artificial muscles are selected from the group of smart materials consisting of electrostrictive polymers, electroactive polymers, conductive polymers, electrostatic devices, piezoelectric polymers, mechano-chemical polymers and gels, shape memory polymers and shape memory alloys.

48. The method of claim 46, further comprising the step of folding at least one of said artificial muscles in an overlapping configuration along a length of said articulated support member.

49. A method of effecting movement in an artificial limb wherein said limb is in signal communication with electromyographic signals obtained from a patient'"'"'s residual muscles, said method comprising the steps of:

providing an articulated support member releasably mounted to said patient in signal communication with said patient'"'"'s residual muscles, said member having at least one joint with a joint axis defined therethrough and further having a free end responsive to electromyogrpahic signals communicated thereby;

attaching a plurality of artificial muscles comprising smart materials to said articulated support member so as to effect movement of said member corresponding to contraction or expansion of said artificial muscles;

folding at least one of said artificial members in an overlapping configuration along a length of said articulated support member; and

providing command circuitry in electrical communication with said residual muscles for communicating said electromyographic signals to said artificial muscles so as to effect said member movement;

said artificial muscles being in electrical communication with said command circuitry such that transmission of signals to said command circuitry effect movement of said member.

50. The method of claim 49 further comprising the step of providing a system for detecting environmental stimulation of said articulated support member and producing corresponding detection signals in response thereto, and for transmitting said detection signals to said command circuitry.

51. The method of claim 50 wherein said system includes a plurality of sensors mounted on said articulated support member to detect environmental stimulation thereof.

52. The method of claim 51 wherein said sensors produce said detection signals to correspond to said environmental stimulation and transmit said detection signals to said command circuitry.

53. The method of claim 52 further comprising the step of providing a portable device in electrical communication with said command circuitry.

54. An assistive device actuated by artificial muscles which provides increased dexterity and agility of an artificial or dysfunctional limb, comprising:

an articulated member having at least one joint pivotable about a corresponding joint axis and having a plurality of artificial muscles comprising smart materials affixed thereto wherein said artificial muscles are in signal communication with a system of sensors mounted on said member, said sensors detecting environmental stimulation of said member and producing detection signals corresponding to said stimulation, said sensors farther transmitting said detection signals to command circuitry in electrical communication with said artificial muscles so as to effect anthropometrical movement of said member in response thereto, said artificial muscles being arranged electrically in a combination of series and parallel current paths such that upon application of voltage to said artificial muscles a change in dimension of said artificial muscles is effected, to thereby cause movement of said member.

55. The device of claim 54, wherein said artificial muscles are mechanically connected between a pair of end plates.

56. The device of claim 54, wherein said artificial muscles are fixed proximate said joint axis to enable large angular movements of said articulated member.

57. The device of claim 54, wherein at least one of said artificial muscles is folded in an overlapping configuration along a length of said articulated member.

58. An assistive device actuated by artificial muscles which provides increased dexterity and agility of an artificial or dysfunctional limb, comprising:

an articulated member having at least one joint pivotable about a corresponding joint axis and having a plurality of artificial muscles comprising smart materials affixed thereto wherein said artificial muscles are in signal communication with a system of sensors mounted on said member, said sensors detecting environmental stimulation of said member and producing detection signals to command circuitry in electrical communication with said artificial muscles so as to effect anthropometrical movement of said member in response thereto, said artificial muscles comprising a bundle of elongate elements that are adapted to change dimension in response to said detection signals resulting in expansion or contraction of such elements and movement of said member.

59. An assistive device according to claim 58, wherein said detection signals are adapted to provide a voltage to said elements.

60. An assistive device according to claim 58, wherein said detection signals are adapted to provide pressure to said elements.

61. An assistive device according to claim 58, wherein said detection signals are adapted to provide a change in temperature to said elements.

62. A method of effecting movement of an artificial limb comprising of steps of:

providing an artificial limb having an articulated support member releasably mounted to a patient;

attaching a plurality of artificial muscles comprising smart materials to said articulated support member for movement of said member corresponding to contraction or expansion of said artificial muscles; and

subjecting selected artificial muscles to a physical condition to cause a change in dimension of said selected artificial muscles, resulting in contraction or expansion of such artificial muscles and thereby effecting movement of said articulated member.

63. The method of claim 62, wherein said subjecting step comprises the application of voltage to said selected artificial muscles.

64. The method of claim 62, wherein said subjecting step comprises the application of pressure to said selected artificial muscles.

65. The method of claim 62, wherein said subject step comprises the application of a change in temperature to said selected artificial muscles.

66. The method of claim 62, wherein said artificial muscles are provided in communication with residual muscles of said patient for communicating electromyographic signals to said artificial muscles so as to produce said physical condition.