Human machine interfaces for lower extremity orthotics

Patent metadata

Field	Value
Publication number	US-9801772-B2
Application number	US-201113877805-A
Country	US
Kind code	B2
Filing date	Oct 6, 2011
Priority date	Oct 6, 2010
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

A system and method by which movements desired by a user of a lower extremity orthotic is determined and a control system automatically regulates the sequential operation of powered lower extremity orthotic components to enable the user, having mobility disorders, to walk, as well as perform other common mobility tasks which involve leg movements, perhaps with the use of a gait aid.

First claim

We claim:

1. A powered lower extremity orthotic, configurable to be coupled to a person, comprising:
an exoskeleton including a waist portion configurable to be coupled to an upper body of the person, at least one leg support configurable to be coupled to at least one lower limb of the person and at least one actuator for shifting of the at least one leg support relative to the waist portion to enable movement of the lower limb of the person;
a plurality of sensors for monitoring a first orientation of said exoskeleton;
at least one additional sensor for monitoring a second orientation of at least one of an arm of the person or a gait aid used by the person;
a controller configured to receive signals from both the plurality of sensors and the at least one additional sensor and regulating operation of the at least one actuator, said controller configured to establish a present state of said powered lower extremity orthotic from a finite plurality of states based on both the first and second orientations and, based on the present state, control the at least one actuator to cause the powered lower extremity orthotic to follow a series of orientations collectively reproducing a natural human motion; and
at least one gait aid used by the person, with the at least one additional sensor also configured to indicate when the at least one gait aid is in contact with a support surface, the controller further configured to:
determine a first height off a ground contact point of the at least one gait aid based on the at least one additional sensor;
determine a second height off the ground contact point of the powered lower extremity orthotic;
subtract the second height from the first height to calculate a height difference; and
transition the powered lower extremity orthotic into a stair climbing mode when the height difference is larger than a pre-defined value.

2. The powered lower extremity orthotic of claim 1 , wherein the at least one lower limb includes two lower limbs and the second orientation is of the at least one gait aid used by the person, said at least one gait aid being constituted by first and second crutches, with the at least one additional sensor also configured to indicate when either of said first and second crutches is in contact with a support surface, and wherein:
said controller configured to determine when the first crutch is lifted off the support surface from a position behind the person and placed in contact with the support surface in front of the person based on signals from the plurality of sensors and the at least one additional sensor;
said controller configured to lift a first of said two lower limbs off the support surface at a first position and swinging forward the first of said two lower limbs, the first of said two lower limbs being on an opposite side of the person to the first crutch; and
said controller further configured to place the first of two lower limbs back on the support surface at a second position at an end of the swinging forward, whereby said powered lower extremity orthotic causes the person to take a forward step.

3. The powered lower extremity orthotic of claim 2 , wherein said controller is configured to repeat the forward step, alternating between the first and second of said lower limbs and, correspondingly, the first and second crutches configured to be held by arms of the person, whereby said powered lower extremity orthotic causes said person to walk forward.

4. The powered lower extremity orthotic of claim 2 , wherein said controller configured to use a difference between readings of said at least one additional sensor from successive support surface contacts to determine a difference between said first and second positions.

5. The powered lower extremity orthotic of claim 1 , wherein the at least one lower limb includes two lower limbs and the second orientation is of the at least one gait aid used by the person, said at least one gait aid being constituted by first and second crutches, with the at least one additional sensor also configured to indicate when either of said first and second crutches is in contact with a support surface, and wherein:
said controller configured to monitor said plurality of sensors and said additional sensor to determine when the person lifts the first crutch off a support surface at a position in front of the person, and places said first crutch in contact with the support surface substantially behind the person;
said controller configured to lift a first of said two lower limbs off the support surface at a first position and swinging said first of two lower limbs backward, said first of two lower limbs being on the opposite side of the person as said first crutch; and
said controller further configured to place said first of two lower limbs back on the support surface at a second position at the end of the backward swinging, whereby said powered lower extremity orthotic causes the person to take a backward step.

6. The powered lower extremity orthotic of claim 5 , wherein said controller is configured to repeat the backward step, alternating between the first and second of said lower limbs and, correspondingly, the first and second crutches configured to be held by arms of the person, whereby said powered lower extremity orthotic causes said person to walk backward.

7. The powered lower extremity orthotic of claim 5 , wherein said controller configured to use a difference between readings of said at least one additional sensor from successive support surface contacts to determine a difference between said first and second positions.

8. The powered lower extremity orthotic of claim 1 , wherein said at least one gait aid further includes at least one sensor capable of indicating that said at least one gait aid has been substantially weighted;
said controller configured to record data from said plurality of sensors, determining, from said orientation of said powered lower extremity orthotic, that said powered lower extremity orthotic is standing; and
said controller further configured to transition said powered lower extremity orthotic into a sitting mode when all of said at least one gait aid is placed generally behind said person and weighted, and further controlling said powered lower extremity orthotic to cause said person to sit.

9. The powered lower extremity orthotic of claim 1 , wherein said at least one gait aid further includes at least one sensor configured to indicate when said at least one gait aid has been substantially weighted; and
said controller configured to measure an orientation of said powered lower extremity orthotic with a plurality of sensors, determine that said powered lower extremity orthotic is sitting, transition said powered lower extremity orthotic into a standing mode when all of said at least one gait aid is placed generally behind said person and weighted, and control the powered lower extremity orthotic to cause said person to stand.

10. The powered lower extremity orthotic of claim 1 , wherein said controller is configured to maintain said powered lower extremity orthotic in a walking mode until an output from said at least one additional sensor deviates substantially from a trajectory that the output normally follows during walking; and
said controller further configured to stop said powered lower extremity orthotic when said output deviates substantially from the trajectory said output normally follows during walking.

11. The powered lower extremity orthotic of claim 1 ,
wherein said controller is configured to maintain said powered lower extremity orthotic in a walking mode until an output from said at least one additional sensor deviates substantially from a beha

Assignees

• Strausser Katherine
• Zoss Adam
• Swift Tim
• Ekso Bionics Inc
• Univ California

Inventors

• Kazerooni Homayoon
• Strausser Katherine
• Zoss Adam
• Swift Tim

Classifications

• A61H2201/165

  Wearable interfaces · CPC title

• A61H2201/1215

  Rotary drive · CPC title

• A61H2201/1616

  Holding means therefor · CPC title

• A61H2201/5028

  Contact activation, i.e. activated at contact with a surface of the user to be treated · CPC title

• A61H2201/5069

  Angle sensors · CPC title