And use of a leg support exoskeleton
11241355 ยท 2022-02-08
Assignee
Inventors
- Wayne Tung (Berkeley, CA, US)
- Minerva Pillai (Redwood City, CA, US)
- Homayoon Kazerooni (Berkeley, CA, US)
Cpc classification
International classification
Abstract
A leg support exoskeleton is strapped on as wearable device to support its user during squatting. The exoskeleton includes a knee joint connected to a first line and a second link, which is configured to allow flexion and extension motion between the first link and the second link. A force generator has a first end that is rotatably connected to the first link. A constraining mechanism is connected to the second link and has at least two operational positions. In a first operational position, the second end of the force generator engages the constraining mechanism, where the first link and the second link flex relative to each other. In a second operational position, the second end of the force generator does not engage the constraining mechanism; the first link and the second link are free to flex and extend relative to each other.
Claims
1. A leg apparatus, configured to be coupled to a leg of a wearer, the leg apparatus comprising: a first link; a second link, coupled to the first link and configured to flex and extend relative the first link; a force generator, comprising a first end and a second end, wherein the first end of the force generator is rotatably coupled to the first link; and a constraining mechanism, having at least a first operational mode and a second operational mode, wherein: when the constraining mechanism is moved into the first operational mode, the second end of the force generator gets engaged with the second link and the force generator provides a resistance torque in response to flexion of the first link and the second link relative to each other, and when the constraining mechanism is moved into the second operational mode, the second end of the force generator is disengaged from the second link, and the first link and the second link are free to flex and extend relative to each other.
2. The leg apparatus of claim 1, wherein the constraining mechanism comprises a pawl coupled to the second link, the pawl having at least a first operational position and a second operational position, wherein: when the pawl is in the first operational position, the second end of the force generator engages to the pawl when the first link and the second link flex relative to each other, and when the pawl is in the second operational position, the second end of the force generator does not engage to the pawl, and the first link and the second link are configured to flex and extend relative to each other.
3. The leg apparatus of claim 2, wherein the pawl is rotatably coupled to the second link.
4. The leg apparatus of claim 3, further comprising a manual tab having at least a first position and a second position and operable by the wearer, wherein: the manual tab moves the constraining mechanism to the first operational mode when the wearer moves the manual tab to the first position, and the manual tab moves the constraining mechanism to the second operational mode when the wearer moves the manual tab to the second position.
5. The leg apparatus of claim 4, further comprising an actuator configured to move the pawl between the first position and the second position.
6. The leg apparatus of claim 1, further comprising a manual tab having at least a first position and a second position and operable by the wearer, wherein: the manual tab moves the constraining mechanism to the first operational mode when the wearer moves the manual tab to the first position, and the manual tab moves the constraining mechanism to the second operational mode when the wearer moves the manual tab to the second position.
7. The leg apparatus of claim 6, wherein the manual tab is configured to slide on the second link and relative to the second link between the first position and the second position.
8. The leg apparatus of claim 6, wherein the manual tab comprises a magnet, and wherein the magnet of the manual tab generates magnetic force configured to move the constraining mechanism between the first operational mode and the second operational mode.
9. The leg apparatus of claim 1, wherein the constraining mechanism comprises: an indentation; and an indentation filler, coupled to the second link and having at least a first operational mode and a second operational mode, wherein: when the indentation filler is in the first operational mode, the indentation is not occupied by the indentation filler and the second end of the force generator is engaged with the indentation when the first link and the second link flex relative to each other, and when the indentation filler is in the second operational mode, the indentation is occupied by the indentation filler, the second end of the force generator dis engaged from the indentation, and the first link and the second link are free to flex and extend relative to each other.
10. The leg apparatus of claim 9, further comprising an actuator configured to move the indentation filler between a first filler position and a second filler position.
11. The leg apparatus of claim 1 further comprising a triggering mechanism configured to automatically move the constraining mechanism between the first operational mode and the second operational mode, wherein the triggering mechanism comprises: an actuator, configured to move the constraining mechanism between the first operational mode and the second operational mode; and a stance sensor, configured to detect if the leg of the wearer is in contact with a ground and to generate an electric signal when the leg of the wearer is in contact with the ground, wherein when the leg of the wearer is contacting the ground, the stance sensor generates the electric signal, and the actuator moves the constraining mechanism to the first operational mode.
12. The leg apparatus of claim 11, wherein the stance sensor is selected from the group consisting of a strain gage sensor, a pressure sensor, a force sensor, a piezoelectric force sensor, a force sensor based on force sensing resistors, and any combination thereof.
13. The leg apparatus of claim 1, wherein one of the first link or the second link is configured to be coupled to a thigh of the wearer.
14. The leg apparatus of claim 1, wherein one of the first link or the second link is configured to be coupled with a shank of the wearer.
15. The leg apparatus of claim 1, wherein the force generator is selected from the group consisting of a gas spring, a compression spring, a coil spring, a leaf spring, an air spring, a tensile spring, and a combination thereof.
16. The leg apparatus of claim 1, wherein the constraining mechanism is configured to be moved by the wearer between the first operational mode and the second operational mode.
17. The leg apparatus of claim 1, further comprising an actuator, configured to move the constraining mechanism between the first operational mode and the second operational mode.
18. The leg apparatus of claim 1, wherein the constraining mechanism is in the first operational mode when the leg of the wearer is on a ground.
19. The leg apparatus of claim 1, further comprising at least one stance detector, configured to generate a stance signal, wherein the constraining mechanism moves to the first operational mode if the stance detector declares the leg of the wearer is on a ground.
20. A leg apparatus configured to be coupled to a leg of a wearer, the leg apparatus comprising: a first link; a second link, coupled to the first link and capable of flexion and extension motion relative the first link; and a force generator, comprising a first end and a second end wherein the first end of the force generator is coupled to the first link, wherein while the leg of the wearer is on a ground, the second end of the force generator is automatically engaged with the second link when the first link and the second link flex relative to each other, and while the leg of the wearer is not on the ground, the second end of the force generator is automatically disengaged from the second link, and the first link and the second link are free to flex and extend relative to each other.
21. The leg apparatus of claim 20 further comprising a stance sensor, configured to detect if the leg of the wearer is in contact with the ground and to generate a first electric signal when the leg of the wearer is in contact with the ground and to generate a second signal when the leg of the wearer is not in contact with the ground.
22. The leg apparatus of claim 21, wherein the stance sensor is located in a location selected from the group consisting of inside a shoe of the wearer, at a bottom of the shoe of the wearer, in a sole of the shoe of the wearer, and any combination thereof.
23. The leg apparatus of claim 21, wherein the stance sensor is selected from the group consisting of a strain gage sensor, a pressure sensor, a force sensor, a piezoelectric force sensor, a force sensor based on force sensing resistors, and any combination thereof.
24. The leg apparatus of claim 20, further comprising an actuator, configured to engage the second end of the force generator with the second link.
25. The leg apparatus of claim 24, wherein the actuator is selected from the group consisting of a solenoid, a linear motor, an electric motor, a servo, a DC motors, a voice coil actuator, a piezoelectric actuator, a spring loaded solenoid, a spring loaded motor, and any combination of these.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
(22)
(23)
(24)
(25)
(26)
(27)
(28)
(29)
(30)
(31)
DETAILED DESCRIPTION
(32) Various embodiments of the invention include an exoskeleton leg that supports the user's leg and knee while squatting. A device according to the invention reduces leg muscle strain while squatting, but allows the user to walk freely without any interference. Various embodiments of the invention are described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown in the figures. These inventions may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements.
(33)
(34)
(35) In operation, when constraining mechanism 130 is moved into its first operational position (or mode), second end 114 of force generator 108 gets rotatably latched to second link 104, only when first link 102 and second link 104 move in the first direction 120 relative to each other. This causes force generator 108 to create a force resisting motion in the first direction 120 of first link 102 relative to second link 104. It is important to realize that, in this first operational position, if first link 102 and second link 104 are moving in the second direction 118 relative to each other, constraining mechanism 130 does not constrain second end 114 of force generator 108 to the second link 104.
(36) In operation when constraining mechanism 130 is moved into its second operational mode (or mode), second end 114 of force generator 108 is free to move and slide on second link 104 at all times (move unimpeded in both first direction 118 and second direction 120).
(37) In summary, exoskeleton leg 100 provides assistance during squatting by moving into its first operational position, but allows for free and unconstrained walking by moving into its second operational position. In the first operational mode, force generator 108 provides a force to support the person during squatting; while in the second operational position, force generator 108 does not interfere with the person's walking and the person is free to walk without any interference from exoskeleton leg 100.
(38)
(39)
(40)
(41)
(42) In some embodiments, exoskeleton leg 100 includes a manual tab 134 having at least two positions and operable by person 200. In some embodiments, as shown in
(43) In some embodiments, manual tab 134 includes a magnet where the magnetic force moves constraining mechanism 130 between its two positions. This arrangement reduces the necessary linkage between manual tab 134 and constraining mechanism 130.
(44)
(45)
(46) In some embodiments, stance detector 160 is located inside user's shoe 212. In some embodiments, stance detector 160 is located on the bottom of user's shoe 212. In some embodiments, detector 160 is located in user's shoe sole. An ordinary person skilled in the art will recognize transmission line 162 can be selected from a set consisting of rope, wire rope, twine, thread, nylon rope, chain, and rod, and any combination of these.
(47)
(48) In some embodiments as shown in
(49) In operation, when stance sensor 164 declares person's leg 208 is on the ground, actuator 166 moves indentation filler 142 away from indentation 140 allowing force generator 108 to engage indentation 140. This allows a supporting force to be generated during squatting. This decreases the person's knee torque and provides support for person 200. However, when stance sensor 160 declares the person's leg 208 is not on the ground, actuator 166 moves indentation filler 142 into indentation 140 preventing force generator 108 from engaging indentation 140. In this position, force generator 108 does not engage indentation 140 when person 200 squats, walks, or doing any movements. This allows person 200 to move freely and unimpeded.
(50)
(51) In some embodiments, stance sensor 164 is located inside user's shoe 212. In some embodiments of the invention, stance sensor 164 is located on the bottom of user's shoe 212. In some embodiments of the invention, stance sensor 164 is located in user's shoe sole.
(52) An ordinary person skilled in the art will recognize stance sensor 164 can be selected from a set consisting of strain gage sensors, pressure sensors, force sensors, piezoelectric force sensor, and force sensors based on force sensing resistors, and any combination of these. An ordinary person skilled in the art will recognize actuator 166 can be selected from a set consisting of solenoids, linear motors, electric motors, servos, DC motors, voice coil actuators, piezoelectric actuators, spring loaded solenoids, and spring loaded motors, and combination of these.
(53) In some embodiments, exoskeleton leg 100 further includes a foot link mechanism 183. In some embodiments, as shown in
(54) As shown in
(55)
(56) This description of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications. This description will enable others skilled in the art to best utilize and practice the invention in various embodiments and with various modifications as are suited to a particular use. The scope of the invention is defined by the following claims.