Passive knee mechanical exoskeleton with gait-friendly characteristics

Abstract

This invention primarily discloses a passive knee joint mechanical exoskeleton, which includes a pivot point positioning unit, a relative motion unit, at least one delayed actuation unit, and at least one energy-storing auxiliary unit. Specifically, the pivot point positioning unit is worn on one of the user's thighs, and the relative motion unit is worn on one of the user's lower legs. The pivot point positioning unit and the relative motion unit are pivotally connected via a first pivot unit and a second pivot unit. According to the design of this invention, the at least one delayed actuation unit is configured to restrict or delay the at least one energy-storing auxiliary unit from entering its primary energy-storing actuation state when the rotation angle of the relative motion unit relative to the first pivot unit and the second pivot unit is within a predetermined angle range, thereby avoiding unnecessary auxiliary interference to the knee joint during normal walking.

Claims

1. A passive knee joint mechanical exoskeleton, comprising: A pivot-point positioning unit for wearing on a user's thigh, comprising: a first contact member configured to contact the anterior side of the thigh; a first upper extension arm extending downward from a first end of the first contact member to face the lateral side of the thigh, and having a first upper pivot structure at its bottom end; and a second upper extension arm extending downward from a second end of the first contact member to face the medial side of the thigh, and having a second upper pivot structure at its bottom end; and a relative movable unit for wearing on a user's lower leg, comprising: a second contact member configured to contact the posterior side of the user's lower leg. A first lower extension arm extends upward from a first end of the second contact member to face the lateral side of the lower leg, and its top end forms a first lower pivot structure; and a second lower extension arm extends upward from a second end of the second contact member to face the medial side of the lower leg, and its top end forms a second lower pivot structure; a delayed-actuation unit includes: a receiving member disposed on the first upper extension arm; and a sliding member including a first component and a second component, wherein the first component is connected to the second component and is located within the receiving member; and an energy-storing auxiliary unit connected to the second component via a first connector and connected to the first lower extension arm via a second connector; wherein the first upper pivot structure and the first lower pivot structure are combined to form a first pivot unit, and the first pivot unit faces the lateral side of the user's knee joint. The second upper pivot structure and the second lower pivot structure are combined to form a second pivot unit, and the second pivot unit faces the medial side of the knee joint. When the rotation angle of the relative motion unit relative to the first pivot unit and the second pivot unit is between a first angle and a second angle, the energy storage auxiliary unit drives the second component to move accordingly, thereby causing the first component to move accordingly within the receiving member. When the rotation angle of the relative motion unit reaches the second angle, the slider moves to a stroke endpoint, at which point the sliding stroke of the slider relative to the receiving member is limited. Subsequently, as the relative motion unit further rotates between the second angle and a third angle, the relative motion unit applies an action to the energy storage auxiliary unit during the rotation process, causing the energy storage auxiliary unit to enter an energy storage state.Specifically, when the relative motion unit rotates in the return direction and its rotation angle decreases accordingly from the third angle, the energy storage auxiliary unit switches from an energy storage state to an energy release state to provide restoring torque during the rotation of the relative motion unit in the return direction.

2. A passive knee joint mechanical exoskeleton, comprising: A pivot point positioning unit for wearing on a user's thigh, comprising: a first contact configured to contact the front side of the thigh; a first upper extension arm extending downward from a first end of the first contact to face the outer side of the thigh, and having a first upper pivot structure at its bottom end; and a second upper extension arm extending downward from a second end of the first contact to face the inner side of the thigh, and having a second upper pivot structure at its bottom end; and a relative movement unit for wearing on a user's lower leg, comprising: a second contact configured to contact the rear side of the user's lower leg; a first lower extension arm extending upward from a first end of the second contact to face the outer side of the lower leg, and having a first lower pivot structure at its top end; and a second lower extension arm extending upward from a second end of the second contact to face the inner side of the lower leg, and having a second lower pivot structure at its top end; A first energy-storing auxiliary unit having a first sliding member; a second energy-storing auxiliary unit having a second sliding member; a first delayed actuation unit; and a second delayed actuation unit; wherein the first upper pivot structure and the first lower pivot structure are combined to form a first pivot unit, the first energy-storing auxiliary unit being disposed within the first pivot unit and facing the outer side of a user's knee joint; wherein the second upper pivot structure and the second lower pivot structure are combined to form a second pivot unit, the second energy-storing auxiliary unit being disposed within the second pivot unit and facing the inner side of the knee joint; wherein the first delayed actuation unit includes a first receiving member formed within the first pivot unit, and the second delayed actuation unit includes a second receiving member formed within the second pivot unit; Specifically, when the rotation angle of the relative motion unit relative to the first pivot unit and the second pivot unit is between a first angle and a second angle, the first sliding member of the first energy storage auxiliary unit changes its position relative to the first receiving member due to the pivoting of the relative motion unit, and does not form force contact with the first receiving member; at the same time, the second sliding member of the second energy storage auxiliary unit also changes its position relative to the second receiving member due to the pivoting of the relative motion unit, and does not form force contact with the second receiving member; Specifically, when the rotation angle of the relative motion unit reaches the second angle, the first slider reaches a first stroke endpoint within the first receiving member, and the second slider reaches a second stroke endpoint within the second receiving member; subsequently, as the relative motion unit further rotates between the second angle and a third angle, the relative motion unit applies an action to the first energy storage auxiliary unit and the second energy storage auxiliary unit during the rotation process, so that the first energy storage auxiliary unit and the second energy storage auxiliary unit enter an energy storage state;Specifically, when the relative motion unit rotates in the return direction and its rotation angle decreases accordingly from the third angle, the first energy storage auxiliary unit and the second energy storage auxiliary unit switch from an energy storage state to an energy release state to provide restoring torque during the rotation of the relative motion unit in the return direction.

3. The passive knee joint mechanical exoskeleton as described in claim 1, wherein, The energy storage auxiliary unit is selected from any one of the groups consisting of hydraulic energy storage damping mechanisms and spring energy storage damping mechanisms.

4. The passive knee joint mechanical exoskeleton as described in claim 1 or 2, wherein, The first contact is fixed to the user's thigh by a fastener, and the first contact has an arc-shaped contact surface, thereby contacting the front (anterior) of the thigh with the arc-shaped contact surface.

5. The passive knee joint mechanical exoskeleton as described in claim 1 or 2, wherein, The second contact is fixed to the user's lower leg by a fastener, and the second contact has an arc-shaped contact surface, thereby contacting the posterior side of the lower leg with the arc-shaped contact surface.

6. The passive knee joint mechanical exoskeleton as described in claim 2, wherein, Both the first energy storage auxiliary unit and the second energy storage auxiliary unit are selected from any one of the groups consisting of torsion springs and double-arm springs.

7. The passive knee joint mechanical exoskeleton as described in claim 1 or 2, wherein, The first upper pivot structure includes: a first receiving groove; and a first bearing disposed in the first receiving groove, having a first through hole; wherein the first receiving groove has a first exposure hole, such that the first through hole portion is exposed through the first exposure hole.

8. The passive knee joint mechanical exoskeleton as described in claim 7, wherein, The second upper pivot structure includes: a second receiving groove; and a second bearing disposed in the second receiving groove, having a second through hole; wherein the second receiving groove has a second exposure hole, such that the second through hole portion is exposed through the second exposure hole.

9. The passive knee joint mechanical exoskeleton as described in claim 8, wherein, The first lower pivot structure includes: a first groove; a first shaft member disposed within the first groove; and a first elastic foot receiving groove communicating with the first groove and serving as the first receiving member; wherein the first energy-storing auxiliary unit is disposed within the first groove, and has an elastic foot serving as the first sliding member and located within the first elastic foot receiving groove; wherein when the first upper pivot structure and the first lower pivot structure are combined, the first shaft member is embedded and fixed within the first through hole of the first bearing; wherein when the relative motion unit rotates between the first angle and the second angle, the elastic foot of the first torsional elastic element is located within the first elastic foot receiving groove and does not form force contact with the groove wall of the first elastic foot receiving groove, thus not entering a torsional state; wherein when the rotation angle of the relative motion unit exceeds the second angle, the elastic foot of the first torsional elastic element forms force contact with the groove wall of the first elastic foot receiving groove, thus entering a torsional state.

10. The passive knee joint mechanical exoskeleton as described in claim 9, wherein, The first stroke endpoint is the relative displacement of the elastic foot of the first energy storage auxiliary unit to a limit position during the pivoting process of the relative motion unit relative to the first pivot unit, and the limit position is defined by the force contact formed between the elastic foot and the groove wall of the first elastic foot receiving groove.

11. The passive knee joint mechanical exoskeleton as described in claim 10, wherein, The second lower pivot structure includes: a second groove; a second shaft member disposed within the second groove; and a second elastic foot receiving groove communicating with the second groove and serving as the second receiving member; wherein the second energy storage auxiliary unit is disposed within the second groove, and has an elastic foot serving as the second sliding member and located within the second elastic foot receiving groove; wherein when the second upper pivot structure and the second lower pivot structure are combined, the second shaft member is embedded and fixed within the second through hole of the second bearing; wherein when the relative motion unit rotates between the first angle and the second angle, the elastic foot of the second torsional elastic element is located within the second elastic foot receiving groove and does not form force contact with the groove wall of the second elastic foot receiving groove, thus not entering a torsional state; wherein when the rotation angle of the relative motion unit exceeds the second angle, the elastic foot of the second torsional elastic element forms force contact with the groove wall of the second elastic foot receiving groove, thus entering a torsional state.

12. The passive knee joint mechanical exoskeleton as described in claim 11, wherein, The second stroke endpoint is the relative displacement of the elastic foot of the second energy storage auxiliary unit to a limit position during the pivoting process of the relative motion unit relative to the second pivot unit, and the limit position is defined by the force contact formed between the elastic foot and the groove wall of the second elastic foot receiving groove.

13. The passive knee joint mechanical exoskeleton as described in claim 1, wherein, The first connector has a first receiving hole, and the second connector has a second receiving hole.

14. The passive knee joint mechanical exoskeleton as described in claim 13 further includes: A mounting member is disposed on the first lower extension arm; a lower connecting member includes a base plate, a lower rod portion and a lower spherical end portion; and an upper connecting member includes an upper rod portion and an upper spherical end portion; wherein the base plate is fixed on the mounting member, and the lower spherical end portion is partially received in the second receiving hole, thereby enabling the second connector to connect the first lower extension arm through the lower connecting member and the mounting member; wherein the upper rod portion extends vertically from the second member, and the upper spherical end portion is partially received in the first receiving hole, thereby enabling the first connector to connect the first upper extension arm through the upper connecting member.

15. The passive knee joint mechanical exoskeleton as described in claim 1, wherein, The receiving member has a side opening slot through which the first component enters the receiving member.

16. The passive knee joint mechanical exoskeleton as described in claim 15, wherein, The side-opening slot has an upper end side and a lower end side, and the travel endpoint is the upper end side.

17. The passive knee joint mechanical exoskeleton as described in claim 16, wherein, The delayed actuation unit further includes: a limiting member selectively disposed at a position between the upper end side and the lower end side; wherein, when the limiting member is not disposed, the upper end side serves as the stroke endpoint when the slider moves; wherein, when the adjustable limiting member is disposed between the upper end side and the lower end side, the limiting member serves as the stroke endpoint when the slider moves.

18. The passive knee joint mechanical exoskeleton as described in claim 12, wherein, The delayed actuation unit further includes: a first limiting member disposed at one position in the first elastic foot receiving groove; and a second limiting member disposed at one position in the second elastic foot receiving groove; wherein, when the first limiting member is not disposed, the first stroke endpoint is defined by the force contact formed between the elastic foot of the first energy storage auxiliary unit and the groove wall of the first elastic foot receiving groove; wherein, when the first limiting member is disposed in the first elastic foot receiving groove, the first limiting member is used to define the first stroke endpoint before the force contact is formed between the elastic foot of the first energy storage auxiliary unit and the groove wall of the first elastic foot receiving groove; wherein, when the second limiting member is not disposed, the second stroke endpoint is defined by the force contact formed between the elastic foot of the second energy storage auxiliary unit and the groove wall of the second elastic foot receiving groove. When the second limiting member is disposed in the second elastic foot receiving groove, the second limiting member is used to define the second stroke endpoint before the elastic foot of the second energy storage auxiliary unit forms the force contact with the groove wall of the second elastic foot receiving groove.

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