Stance Controller and Related Methods

• US 20160074180A1
• Filed: 09/14/2015
• Published: 03/17/2016
• Est. Priority Date: 09/12/2014
• Status: Active Grant

• Current Assignee: Rehabilitation Institute of Chicago (Tenet Healthcare Corporation)
• Original Assignee: Rehabilitation Institute of Chicago (Tenet Healthcare Corporation)
• Inventors: Lenzi, Tommaso, Sensinger, Jon
• Granted Patent: US 10,799,373 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61F 2/60 Artificial legs or feet or parts thereof
• CPC Class Codes: A61F 2/64 Knee joints
• CPC Class Codes: A61F 2/6607 Ankle joints
• CPC Class Codes: A61F 2/70 electrical
• CPC Class Codes: A61F 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61F 2/74 fluid , i.e. hydraulic or pneumatic
• CPC Class Codes: A61F 2/80 Sockets, e.g. of suction type
• 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 2002/762 for measuring dimensions, e.g. a distance
• CPC Class Codes: A61F 2002/7625 for measuring angular position
• CPC Class Codes: A61F 2002/7635 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/764 for measuring acceleration

Abstract

Systems and methods are disclosed for operating a joint of a prosthesis during a phase of stance. In an embodiment, a method for such operation comprises determining a joint angle of the joint, determining a walking speed of the prosthesis, retrieving a torque value from a lookup table stored in a memory, on the basis of the joint angle and the walking speed, and initiating a signal to apply a torque to the joint of the prosthesis in an amount based on the torque value.

Claims

1. A method for operating a joint of a prosthesis during a phase of stance, comprising:

a. determining a joint angle of the joint;

b. determining a walking speed of the prosthesis;

c. retrieving a torque value from a lookup table stored in a memory, on the basis of the joint angle and the walking speed; and

d. initiating a signal to apply a torque to the joint of the prosthesis in an amount based on the torque value.

2. The method of claim 1, further comprising determining a ground inclination of the prosthesis, wherein the step of retrieving the torque value from the lookup table stored in the memory is also taken on the basis of the ground inclination.

3. The method of claim 1, wherein the method is used to control the prosthesis during an early phase of stance, a mid-phase of stance, and a late phase of stance.

4. The method of claim 1, wherein the joint is the knee joint.

5. The method of claim 1, wherein the joint is the ankle joint.

6. A method for operating a prosthesis comprising a knee joint and an ankle joint during a phase of stance, comprising performing the method of claim 1 for the knee joint and performing the method of claim 1 for the ankle joint.

7. The method of claim 1, where the torque value is retrieved from the lookup table using interpolation.

8. The method of claim 1, wherein the signal to apply the torque to the joint is modified to normalize the torque to apply, on the basis of the weight of the user of the prosthesis.

9. The method of claim 2, wherein the method is used to control the prosthesis during an early phase of stance, a mid-phase of stance, and a late phase of stance.

10. The method of claim 2, wherein the joint is the knee joint.

11. The method of claim 2, wherein the joint is the ankle joint.

12. A method for operating a prosthesis comprising a knee joint and an ankle joint during a phase of stance, comprising performing the method of claim 2 for the knee joint and performing the method of claim 2 for the ankle joint.

13. The method of claim 2, where the torque value is retrieved from the lookup table using interpolation.

14. The method of claim 2, wherein the signal to apply the torque to the joint is modified to normalize the torque to apply, on the basis of the weight of the user of the prosthesis.

15. A method for operating a joint of a prosthesis, comprising:

a. setting the prosthesis to a first stance phase, and while the prosthesis is in the first stance phase,

determining a first joint angle of the joint;

determining a first walking speed of the prosthesis;

retrieving a first torque value from a lookup table stored in a memory, on the basis of the first joint angle and the first walking speed; and

initiating a first signal to apply a torque to the joint in an amount based on the first torque value;

b. setting the prosthesis to a second stance phase and while the prosthesis is in the second stance phase,

determining a second joint angle of the joint;

determining a second walking speed of the prosthesis;

retrieving a second torque value from a lookup table stored in a memory, on the basis of the second joint angle and the second walking speed; and

initiating a second signal to apply a torque to the joint in an amount based on the second torque value.

16. The method of claim 15, further comprising smoothing the second signal after a transition from the first stance phase to the second stance phase.

17. The method of claim 16, wherein the smoothing occurs during the approximately 20 ms following the transition.

18. The method of claim 15, wherein the step of setting the prosthesis to a second stance phase occurs when the load on the prosthesis is greater than a percentage of the body weight of a user of the prosthesis.

19. The method of claim 15, wherein the step of setting the prosthesis to a second stance phase occurs when the movement of an ankle joint of the prosthesis inverts between dorsiflexion and plantarflexion.

20. A method for operating a prosthesis during a phase of stance, comprising determining an amount of torque to apply to at least one joint of the device, wherein the amount is stored in a lookup table stored in a memory and is determined at least in part on the basis of a joint angle and a walking speed of the prosthesis.