Hybrid terrain-adaptive lower-extremity systems

• US 8,419,804 B2
• Filed: 09/01/2009
• Issued: 04/16/2013
• Est. Priority Date: 09/04/2008
• Status: Active Grant

• Current Assignee: Otto Bock HealthCare LP (Nader Holding GmbH & Co. KG)
• Original Assignee: iWalk Incorporated (Ottobock SE & Co. KGaA)
• Inventors: Herr, Hugh Miller, Casler, Rick, Han, Zhixiu
• Primary Examiner(s): Willse, David H.
• Application Number:
  US12/552,036
• Publication Number:
  US 20100113980A1
• Time in Patent Office: 1,323 Days
• Field of Search: None
• US Class Current: 623/24
• 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 2/72 Bioelectric control, e.g. myoelectric
• CPC Class Codes: A61F 2002/5003 having damping means, e.g. shock absorbers
• CPC Class Codes: A61F 2002/5007 having elastic means different from springs, e.g. including an elastomeric insert
• CPC Class Codes: A61F 2002/5018 for adjusting angular orientation
• CPC Class Codes: A61F 2002/503 for adjusting elasticity, flexibility, spring rate or mechanical tension
• CPC Class Codes: A61F 2002/5033 for adjusting damping
• CPC Class Codes: A61F 2002/5079 Leaf springs A61F2002/6657 takes precedence
• CPC Class Codes: A61F 2002/5087 Sound-damping or noise-reducing means
• CPC Class Codes: A61F 2002/6614 Feet
• CPC Class Codes: A61F 2002/6836 Gears specially adapted therefor, e.g. reduction gears
• 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 2002/7625 for measuring angular position
• CPC Class Codes: A61F 2002/763 for measuring spatial position, e.g. global positioning system [GPS]
• CPC Class Codes: A61F 2002/7635 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/764 for measuring acceleration
• CPC Class Codes: A61F 2002/7645 for measuring torque, e.g. hinge or turning moment, moment of force
• CPC Class Codes: A61F 2002/7665 : for measuring temperatures
• CPC Class Codes: A61F 2005/0155 : with actuating means
• CPC Class Codes: A61F 2005/0169 : with damping means
• CPC Class Codes: A61H 1/0266 : Foot
• CPC Class Codes: A61H 2003/001 : on steps or stairways
• CPC Class Codes: A61H 3/00 : Appliances for aiding patients or disabled persons to walk about apparatus for helping babies to walk A47D13/04 ; applying electrical currents by contact electrodes for stimulating motor muscles, e.g. walking assistance A61N1/36003
• CPC Class Codes: B25J 9/0006 : Exoskeletons, i.e. resembling a human figure
• CPC Class Codes: G01L 5/0028 : Force sensors associated with force applying means G01L5/0052, G01L5/0057, G01L5/0061 take precedence
• CPC Class Codes: G01L 5/0061 : Force sensors associated with industrial machines or actuators for the specific machine or actuator involved see relevant class, e.g. F01, F04, F16, B66, E21
• CPC Class Codes: G01P 21/00 : Testing or calibrating of apparatus or devices covered by the preceding groups
• CPC Class Codes: H02K 7/06 : Means for converting reciprocating motion into rotary motion or vice versa
• CPC Class Codes: H02K 7/116 : with gears

Abstract

Hybrid terrain-adaptive lower-extremity apparatus and methods that perform in a variety of different situations by detecting the terrain that is being traversed, and adapting to the detected terrain. In some embodiments, the ability to control the apparatus for each of these situations builds upon five basic capabilities: (1) determining the activity being performed; (2) dynamically controlling the characteristics of the apparatus based on the activity that is being performed; (3) dynamically driving the apparatus based on the activity that is being performed; (4) determining terrain texture irregularities (e.g., how sticky is the terrain, how slippery is the terrain, is the terrain coarse or smooth, does the terrain have any obstructions, such as rocks) and (5) a mechanical design of the apparatus that can respond to the dynamic control and dynamic drive.

Claims

1. A method for minimizing the effect of accelerometer and rate gyro errors on a lower extremity prosthesis or orthosis comprising a foot member, a lower leg member, and an ankle joint for connecting the foot member to the lower leg member, the method comprising using a controller on the prosthesis or orthosis for:

determining at least one velocity error contribution for an accelerometer signal output by an accelerometer coupled to the lower leg member when the ankle joint is substantially stationary during a walking cycle of the prosthesis or orthosis; and

determining at least one velocity error contribution for an inertial pose misalignment signal output by an inertial measurement unit coupled to the lower leg member when the ankle joint is substantially stationary during a walking cycle of the prosthesis or orthosis by solving a set of strapdown integration equations to derive at least one world frame-referenced ankle joint parameter.

2. The method of claim 1, wherein the inertial pose misalignment signal output by the inertial measurement unit is a rate gyro signal output by a rate gyro.

3. The method of claim 2, comprising computing the pose of the lower leg member using signals output by the accelerometer and rate gyro.

4. The method of claim 3, comprising correcting the computed pose of the lower leg member using the velocity error contributions.

5. The method of claim 1, wherein the velocity error contributions are determined during a portion of a controlled dorsiflexion state of the walking cycle.

6. The method of claim 2, comprising determining velocity error contributions for an accelerometer signal and rate gyro signal output by an accelerometer and rate gyro coupled to a thigh member of the prosthesis or orthosis when the ankle joint is substantially stationary during a walking cycle of the prosthesis or orthosis.

7. The method of claim 2, comprising determining velocity error contributions for an accelerometer signal and rate gyro signal output by an accelerometer and rate gyro coupled to a thigh member of the prosthesis or orthosis when a computed position on a foot member is substantially stationary.

8. The method of claim 6, comprising measuring the angle of the lower leg member relative to the thigh member.

9. The method of claim 6, comprising determining velocity error contributions for an accelerometer signal and rate gyro signal output by an accelerometer and rate gyro coupled to a wearer'"'"'s torso when the ankle joint is substantially stationary during a walking cycle of the prosthesis or orthosis.

10. The method of claim 9, comprising measuring the angle of the thigh member relative to the wearer'"'"'s torso.

11. The method of claim 1, wherein the inertial measurement unit comprises at least one of the accelerometer and the rate gyro.

12. The method of claim 1, wherein the ankle joint parameter is selected from the group consisting of position, velocity, and orientation.