And use of a leg support exoskeleton
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.
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.