Active muscle assistance device and method

• US 20040102723A1
• Filed: 11/06/2003
• Published: 05/27/2004
• Est. Priority Date: 11/25/2002
• Status: Active Grant

• Current Assignee: AlterG, Inc.
• Original Assignee: Tibion Corporation (AlterG, Inc.)
• Inventors: Horst, Robert W.
• Granted Patent: US 6,966,882 B2
• Time in Patent Office: Days
• US Class Current: 601/5
• CPC Class Codes: A61H 1/0237 for the lower limbs
• CPC Class Codes: A61H 1/024 Knee A61H1/0255 takes precedence
• CPC Class Codes: A61H 1/0244 Hip A61H1/0255 takes precedence
• CPC Class Codes: A61H 1/0266 Foot
• CPC Class Codes: A61H 1/0274 for the upper limbs
• CPC Class Codes: A61H 2201/0165 Damping, vibration related features
• CPC Class Codes: A61H 2201/1215 Rotary drive
• CPC Class Codes: A61H 2201/123 Linear drive
• CPC Class Codes: A61H 2201/1642 Holding means therefor
• CPC Class Codes: A61H 2201/165 Wearable interfaces
• CPC Class Codes: A61H 2201/1676 Pivoting
• CPC Class Codes: A61H 2201/5007 computer controlled
• CPC Class Codes: A61H 2201/5035 Several programs selectable
• CPC Class Codes: A61H 2201/5061 Force sensors
• CPC Class Codes: A61H 2201/5071 Pressure sensors
• CPC Class Codes: A61H 2230/60 Muscle strain, i.e. measured on the user, e.g. Electromyography [EMG]
• CPC Class Codes: A61H 3/00 Appliances for aiding patients or disabled persons to walk about apparatus for helping babies to walk A47D13/04; orthopaedic devices for correcting deformities of, or supporting, limbs A61F5/0102; exercising apparatus for the feet or toes A63B23/10; stairways or ramps E04F11/00
• CPC Class Codes: A61H 3/008 Using suspension devices for supporting the body in an upright walking or standing position, e.g. harnesses drawing-out devices A61H1/0218
• CPC Class Codes: Y10S 601/23 including biological sensors

Abstract

A method for controlling movement using an active powered device including an actuator, joint position sensor, muscle stress sensor, and control system. The device provides primarily muscle support although it is capable of additionally providing joint support (hence the name “active muscle assistance device”). The device is designed for operation in several modes to provide either assistance or resistance to a muscle for the purpose of enhancing mobility, preventing injury, or building muscle strength. The device is designed to operate autonomously or coupled with other like device(s) to provide simultaneous assistance or resistance to multiple muscles.

Claims

1. An apparatus for controlling joint movement and reducing muscle stress, comprising

a first fastening means;

a second fastening means;

a stationary portion coupled to the first fastening means;

a moving portion coupled to the second fastening means, the stationary and moving portions being attachable proximate to a joint of the human body with the first and second fastening means, respectively, and participating in movements of the joint;

detection means operative to detect joint movements and muscle stress;

an actuator operative, when energized, to exert force between the stationary and moving portions; and

control means responsive to the detection means for controlling the energizing and de-energizing of the actuator, wherein the energizing is controllable for directing the force so that, when assisting, the force reduces the muscle stress and, when resisting, the force opposes joint movement.

2. An apparatus as in claim 1 having user selectable modes of operation, including assist and resist modes.

3. An apparatus as in claim 2 wherein the user selectable modes further include an idle mode.

4. An apparatus as in claim 2, wherein the user selectable modes further include a rehabilitate mode.

5. An apparatus as in claim 2, wherein the user selectable modes further include a monitor mode.

6. An apparatus as in claim 2 wherein the force is exerted for opposing the joint movement in the resist mode.

7. An apparatus as in claim 4 wherein the force is exerted for assisting to reduce the muscle stress in the assist and rehabilitation modes.

8. An apparatus as in claim 1 operative to allow free joint movement before energizing the actuator and when the actuator is de-energized so as to cancel the force between the stationary and moving portions.

9. An apparatus as in claim 1 wherein the detection means is operative to determine if there is joint movement that requires the force for opposing the joint movement.

10. An apparatus as in claim 1 wherein the detection means is operative to determine if a muscle associated with the joint movement is under stress and requiring the force for assisting to reduce the muscle stress.

11. An apparatus as in claim 1, wherein the actuator is an electrostatic actuator.

12. An apparatus as in claim 11, wherein the electrostatic actuator has a stationary component and a moving component movably mounted proximate to the stationary component and capable, when the actuator is not energized, of moving freely in a plane substantially parallel to the surface of the stationary component.

13. An apparatus as in claim 11 wherein the electrostatic actuator is configured as a rotary actuator in which the moving and stationary components share an axis running through their midpoints around which the moving component rotates clockwise or counter clockwise depending on the joint movement.

14. An apparatus as in claim 1 in which the actuator is coupled to both the stationary and moving portions to facilitate the assistance or resistance with extension and flexion associated with the joint movement.

15. An apparatus as in claim 1 being configured with an exoskeletal frame for attachment to a limb above and below the joint such that the actuator is located on a lateral side of the limb.

16. An apparatus as in claim 1 wherein the actuator is coupled to the stationary portion, moving portion, or both, at a location proximate to a pivot point of the joint.

17. An apparatus as in claim 11 wherein the electrostatic actuator is configured with two portions one of which being capable of moving in a plane substantially proximate and parallel to the other, each portion having a plurality of electrodes which in the portion capable of moving are connected to ground and in the other portion are electrically connected in a predetermined order to a multi-phase driving signal for inducing an electrostatic field therebetween.

18. An apparatus as in claim 17 wherein the multi-phase driving signal is one of sinusoidal and pulsed.

19. An apparatus as in claim 17 wherein the portion capable of moving is supported rotatbaly over the other part.

20. An apparatus as in claim 11, wherein the electrostatic actuator has a stator made of a first plurality of two-dimensional structures stacked over each other and a moving part, made of a second plurality of two-dimensional structures stacked over each other and interleaved with the first plurality of two-dimensional structures of the stator such that adjacent two-dimensional structures are electrically isolated from each other.

21. An apparatus as in claim 20, wherein the moving part has at least one set of electrodes connected to a fixed voltage, and the stator has multiple sets of electrodes with each set independently switchable between high and lower voltages.

22. An apparatus as in claim 1 wherein the stationary portion, moving portion, or both, have a rigid structure.

23. An apparatus as in claim 1 wherein the detection means includes a stress sensor in response to which the assistance is provided and a movement sensor in response to which the resistance is provided.

24. An apparatus as in claim 1 further comprising a low battery warning indication coupled to the control means and communicated to a user by a vibration mode of the actuator.

25. An apparatus as in claim 5 further comprising means for recording measurements associated with joint movements in the monitor mode.

26. An apparatus as in claim 1 wherein the apparatus fits and can be worn under a person'"'"'s garment.

27. An apparatus as in claim 1 wherein the actuator is mechanically coupled with a gear or belt for exerting the force.

28. An apparatus as in claim 1 configured as a knee assistance and rehabilitation device.

29. An apparatus as in claim 1 wherein transitioning from de-energizing to energizing, and vice-versa, of the actuator is controllable to dampen such transitions and prevent a joint from buckling.

30. An apparatus as in claim 1 further comprising a regenerative braking circuit coupled to a power supply for absorbing any external force induced on the actuator by the joint movement.

31. An apparatus as in claim 1 wherein the actuator is a DC motor, servomotor, or gear motor.

50. An apparatus as in claim 1 further comprising a regenerative braking circuit coupled to a power supply for absorbing any external force induced on the electrostatic actuator by the joint movement.

32. An apparatus for controlling joint movement and reducing muscle stress, comprising

a first fastening means;

a second fastening means;

a stationary portion coupled to the first fastening means;

a moving portion coupled to the second fastening means, the stationary and moving portions being attachable proximate to a joint of the human body with the first and second fastening means, respectively, and participating in movements of the joint;

detection means operative to detect joint movements and muscle stress;

an electrostatic actuator operative, when energized, to exert force between the stationary and moving portions; and

control means responsive to the detection means for controlling the energizing and de-energizing of the electrostatic actuator, wherein the energizing is controllable for directing the force so that, when assisting, the force reduces the muscle stress.

33. An apparatus as in claim 32 wherein the energizing is further controllable for directing the force so that, when resisting, the force opposes joint movement.

34. An apparatus as in claim 33 having user selectable modes of operation, including assist and resist modes.

35. An apparatus as in claim 34 wherein the user selectable modes further include an idle mode.

36. An apparatus as in claim 34, wherein the user selectable modes further include a rehabilitate mode.

37. An apparatus as in claim 34, wherein the user selectable modes further include a monitor mode.

38. An apparatus as in claim 32, wherein the electrostatic actuator has a stationary component and a moving component movably mounted proximate to the stationary component and capable, when the actuator is not energized, of moving freely in a plane substantially parallel to the surface of the stationary component.

39. An apparatus as in claim 32 wherein the electrostatic actuator is configured as a rotary actuator in which the moving and stationary components share an axis running through their midpoints around which the moving component rotates clockwise or counter clockwise depending on the joint movement.

40. An apparatus as in claim 32 in which the electrostatic actuator is coupled to both the stationary and moving portions to facilitate the assistance or resistance with extension and flexion associated with the joint movement.

41. An apparatus as in claim 32 being configured with an exoskeletal frame for attachment to a limb above and below the joint such that the electrostatic actuator is located on a lateral side of the limb.

42. An apparatus as in claim 32 wherein the electrostatic actuator is coupled to the stationary portion, moving portion, or both, at a location proximate to a pivot point of the joint.

43. An apparatus as in claim 32 wherein the electrostatic actuator is configured with two portions one of which being capable of moving in a plane substantially proximate and parallel to the other, each portion having a plurality of electrodes which in the portion capable of moving are connected to ground and in the other portion are electrically connected in a predetermined order to a multi-phase driving signal for inducing an electrostatic field therebetween.

44. An apparatus as in claim 43 wherein the multi-phase driving signal is one of sinusoidal and pulsed.

45. An apparatus as in claim 43 wherein the portion capable of moving is supported rotatbaly over the other part.

46. An apparatus as in claim 32, wherein the electrostatic actuator has a stator made of a first plurality of two-dimensional structures stacked over each other and a moving part, made of a second plurality of two-dimensional structures stacked over each other and interleaved with the first plurality of two-dimensional structures of the stator such that adjacent two-dimensional structures are electrically isolated from each other.

47. An apparatus as in claim 46, wherein the moving part has at least one set of electrodes connected to a fixed voltage, and the stator has multiple sets of electrodes with each set independently switchable between high and lower voltages.

48. An apparatus as in claim 32 wherein the apparatus fits and can be worn under a person'"'"'s garment.

49. An apparatus as in claim 32 wherein transitioning from de-energizing to energizing, and vice-versa, of the electrostatic actuator is controllable to dampen such transitions and prevent a joint from buckling.

51. A method for movement control with a powered device, comprising:

fastening a powered device at points above and below a joint, the powered device having an actuator;

setting a desired mode of operation of the powered device;

detecting, at the powered device, an indicia of joint movement or muscle stress with flexion or extension of the joint; and

activating the actuator to exert force, the activating being controllable for directing the force so that, when assisting, the force reduces the muscle stress and, when resisting, the force opposes the joint movement.

52. A method as in claim 51 wherein the desired mode of operation is user selectable and includes assist and resist modes.

53. A method as in claim 52 wherein the desired mode further includes idle, rehabilitate and monitor modes.

54. A method for movement control with a powered device, comprising:

fastening a powered device at points above and below a joint, the powered device having an electrostatic actuator;

setting a desired mode of operation of the powered device;

detecting, at the powered device, an indicia of joint movement or muscle stress with flexion or extension of the joint; and

activating the electrostatic actuator to exert force, the activating being controllable for directing the force so that, when assisting, the force reduces the muscle stress.

55. A method as in claim 54, wherein the activating is further controllable for directing the force so that, and, when resisting, the force opposes the joint movement.

56. A method as in claim 55 wherein the desired mode of operation is user selectable and includes assist and resist modes.

57. A method as in claim 56 wherein the desired mode further includes idle, rehabilitate and monitor modes.

58. A computerized system for controlling movement, comprising:

a processing unit;

detection means for detecting joint movement and muscle stress;

an actuator operative to exert force; and

a memory with program code for causing the processing unit to receive an indication as to which mode of operation is selected and in response thereto obtain from the detector means, based on the selected mode, an indicia of muscle stress or joint movement, or both, the program code further causing the processor, based on the selected mode and indicia, to activate the actuator or maintain it idle, the activating being controllable for directing the force so that, when assisting, the force reduces the muscle stress and, when resisting, the force opposes the joint movement.

59. A computerized system for controlling movement, comprising:

a processing unit;

detection means for detecting joint movement and muscle stress;

an electrostatic actuator operative to exert force; and

a memory with program code for causing the processing unit to receive an indication as to which mode of operation is selected and in response thereto obtain from the detector means, based on the selected mode, an indicia of muscle stress or joint movement, or both, the program code further causing the processor, based on the selected mode and indicia, to activate the electrostatic actuator or maintain it idle, the activating being controllable for directing the force so that, when assisting, the force reduces the muscle stress.

60. A computerized system as in claim 59 wherein the activating is further controllable for directing the force so that, when resisting, the force opposes the joint movement.