Method of Using Powered Orthotic Device

• US 20070191743A1
• Filed: 04/19/2007
• Published: 08/16/2007
• Est. Priority Date: 11/21/2002
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Narendran, Kailas, McBean, John
• Granted Patent: US 7,367,958 B2
• Time in Patent Office: Days
• US Class Current: 601/5
• CPC Class Codes: A61B 5/389 Electromyography [EMG]
• CPC Class Codes: A61B 5/4528 Joints A61B5/4533, A61B5/4538 take precedence
• CPC Class Codes: A61F 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61H 1/0277 Elbow
• CPC Class Codes: A61H 2205/06 Arms

Abstract

A method of providing rehabilitation movement training for a person suffering from nerve damage, stroke, spinal cord injury, neurological trauma or neuromuscular disorder in attempting to move a body part about a joint using a powered orthotic device includes sensing at least one electromyographic signal of a muscle associated with motion about the joint, applying in a first direction with respect to the joint a force having a magnitude that is a first function of the at least one sensed electromyographic signal, and applying in a second direction with respect to the joint a return force that is a second function of the at least one sensed electromyographic signal, wherein the second function differs from the first function.

Claims

1. A method of providing rehabilitation movement training for a person suffering from nerve damage, stroke, spinal cord injury, neurological trauma or neuromuscular disorder in attempting to move a body part about a joint using a powered orthotic device, the method comprising:

sensing at least one electromyographic signal of a muscle associated with motion about the joint;

applying in a first direction with respect to the joint a force having a magnitude that is a first function of the at least one sensed electromyographic signal; and

applying in a second direction with respect to the joint a return force that is a second function of the at least one sensed electromyographic signal, wherein the second function differs from the first function.

2. A method according to claim 1, wherein applying in a first direction includes applying a force that has a magnitude proportional to the magnitude of the at least one sensed electromyographic signal.

3. A method according to claim 1, wherein applying in a first direction includes applying a force that is proportional to a first sensed electromyographic signal and is independent of a second sensed electromyographic signal.

4. A method according to claim 1, wherein applying in a second direction includes applying a return force that is a constant, independent of the at least one sensed electromyographic signal.

5. A method according to claim 1, wherein applying in a first direction includes applying a force that is a non-linear function of the at least one sensed electromyographic signal.

6. A method according to claim 1, further comprising:

processing the at least one sensed electromyographic signal, wherein applying in the first direction includes applying a force having a magnitude that is a first function of the at least one sensed electromyographic signal after the at least one sensed electromyographic signal has been processed.

7. A method according to claim 6, wherein processing the at least one sensed electromyographic signal includes implementing a control algorithm for applying the force in the first direction so that the magnitude of the force is not directly proportional to the magnitude of the at least one sensed electromyographic signal.

8. A method according to claim 7, wherein the control algorithm takes into account non-linearities including saturation.

9. A method according to claim 7, wherein the control algorithm implements a pre-programmed series of motions.

10. A method according to claim 1, wherein applying in a second direction with respect to the joint a return force includes applying a spring return force.

11. A method of providing rehabilitation movement training for a person suffering from nerve damage, stroke, spinal cord injury, neurological trauma or neuromuscular disorder in attempting to move a body part about a joint using a powered orthotic device, the method comprising:

sensing an electromyographic signal of a muscle associated with motion about the joint;

applying in a first direction with respect to the joint a force having a magnitude related to a magnitude of the sensed electromyographic signal; and

applying in a second direction with respect to the joint a return force in the absence of a sensed electromyographic signal of the muscle.

12. A method according to claim 11, wherein the force in the first direction has a magnitude proportional to the magnitude of the sensed electromyographic signal.

13. A method according to claim 11, further comprising:

processing the sensed electromyographic signal, wherein applying in the first direction a force includes applying a force having a magnitude related to the magnitude of the sensed electromyographic signal after the sensed electromyographic signal has been processed.

14. A method according to claim 13, wherein processing the sensed electromyographic signal includes implementing a control algorithm for applying the force in the first direction so that the magnitude of the force is not directly proportional to the magnitude of the sensed electromyographic signal.

15. A method according to claim 14, wherein the control algorithm takes into account non-linearities including saturation.

16. A method according to claim 14, wherein the control algorithm implements a pre-programmed series of motions.

17. A method according to claim 11, wherein applying in a second direction with respect to the joint a return force includes applying a spring return force.