HUMAN EXOSKELETON

Abstract

A human exoskeleton includes a first skeletal structure with a first coupling unit for coupling to a first part of a human body, a second skeletal structure connected to the first skeletal structure in an articulated manner and including a second coupling unit for coupling to a second part of the human body. An adjustment unit acts between the first and second skeletal structures, and includes at least one adjustable flow rate hydraulic actuator unit and a hydraulic unit that acts thereon and which has two pump connections. The first pump connection is fluidly connected to a working chamber of the actuator unit via a pressure line. An outlet line has a flow throttle and a calming tank is downstream of the throttle. The first pump connection is fluidly connected to the second pump connection via the outlet line and the calming tank, the outlet line having a flow therethrough when pressure is applied to the working chamber.

Claims

1-17. (canceled)

18. A human exoskeleton for coupling to a human body, comprising: a first skeletal structure with a first coupling unit suitable for coupling to a first part of the human body; a second skeletal structure connected to the first skeletal structure in an articulated manner and having a second coupling unit suitable for coupling it to a second part of the human body; an adjustment unit acting between the first skeletal structure and the second skeletal structure, the adjustment unit comprising; at least one hydraulic actuator unit having a working chamber; and a hydraulic unit which acts on the at least one hydraulic actuator unit, the hydraulic unit having first and second pump connections and being configured to have an adjustable flow rate; a pressure line connecting the working chamber of the at least one hydraulic actuator unit to the first pump connection of the hydraulic unit; an outlet line having a flow throttle disposed therein; and a calming tank downstream of the flow throttle; wherein the first pump connection of the hydraulic unit is fluidly connected to the second pump connection via the outlet line and the calming tank, the outlet line having a flow therethrough when pressure is applied to the working chamber of the at least one hydraulic actuator unit.

19. The exoskeleton according to claim 18, wherein the hydraulic unit comprises a variable-speed electric motor.

20. The exoskeleton according to claim 18, wherein the hydraulic unit comprises a hydraulic pump which is adjustable in flow rate.

21. The exoskeleton according to claim 18, wherein the flow throttle is adjustable.

22. The exoskeleton according to claim 18, wherein the calming tank is configured as a closed expansion tank.

23. The exoskeleton according to claim 18, wherein: the working chamber is a first working chamber; the at least one actuator unit further comprises a second working chamber acting in an opposite direction to the first working chamber; and the hydraulic unit is reversible.

24. The exoskeleton according to claim 23, further comprising: a second pressure line connecting the second pump connection of the hydraulic unit to the second working chamber of the at least one actuator unit; a second outlet line having a second flow throttle disposed therein, the calming tank being downstream of the second flow throttle; wherein the second pump connection of the hydraulic unit is fluidly connected to the first pump connection via the second outlet line and the calming tank, the second outlet line having a flow therethrough when pressure is applied to the second working chamber of the at least one hydraulic unit.

25. The exoskeleton according to claim 24, wherein the at least one actuator unit comprises at least one double-acting linear actuator having the first and the second working chamber.

26. The exoskeleton according to claim 25, wherein the at least one actuator unit comprises at least one linear actuator configured as a synchronized cylinder.

27. The exoskeleton according to claim 26, wherein the at least one linear actuator comprises exactly one linear actuator.

28. The exoskeleton according to claim 24, wherein the at least one actuator unit comprises two linear actuators operating in opposite directions and configured as differential cylinders.

29. The exoskeleton according to claim 28, wherein the at least one actuator unit comprises two double-acting differential cylinders in cross-connection to one another.

30. The exoskeleton according to claim 24, further comprising a suction line assembly with two suction line portions each bypassing one of the flow throttles.

31. The exoskeleton according to claim 30, wherein the suction line assembly comprises a shuttle valve.

32. The exoskeleton according to claim 30, wherein the suction line assembly comprises two separate check valves.

33. The exoskeleton according to claim 18, wherein: the working chamber is a first working chamber; the at least one actuator unit further comprises a second working chamber acting in an opposite direction to the first working chamber; and the hydraulic unit is a non-reversible hydraulic unit with a downstream flow reversing valve.

34. The exoskeleton according to claim 18, wherein the at least one hydraulic actuator unit comprises a rotary actuator.

35. The exoskeleton according to claim 18, further comprising a shut-off valve operable to shut off the at least one working chamber.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a schematic view of a first exemplary embodiment of an exoskeleton configured for coupling to a leg in accordance with the invention; and

[0021] FIG. 2 is a schematic view of a second exemplary embodiment of an exoskeleton configured for coupling to a leg in accordance with the invention.

DETAILED DESCRIPTION OF THE PERFERRED EMBODIMENT

[0022] The human exoskeleton shown in FIG. 1 of the drawing in its intended use, namely coupled to a human leg, comprises a first skeletal structure 1 and a second skeletal structure 3 connected to it via a joint 2. The first skeletal structure 1 has a first coupling unit 6 suitable for coupling to a first part 4 of the leg, namely the thigh 5; and the second skeletal structure 3 has a second coupling unit 9 suitable for coupling to a second part 7 of the leg, namely the lower leg 8.

[0023] An adjustment unit 10 acts between the first skeleton structure 1 and the second skeleton structure 3. It comprises a hydraulic actuator unit 11 and a hydraulic unit 12 which acts upon it. The actuator unit 11 comprises two linear actuators 14 which are configured as double-acting differential cylinders 13. These are mechanically positively coupled to each other and operate in opposite directions in that when the second skeleton structure 3 is pivoted relative to the first skeleton structure 1 with respect to the joint 2 (arrows , ), the piston rod 15 of one of the linear actuators 14 retracts, whereas the piston rod 15 of the other linear actuator 14 extends. The two linear actuators 14 are cross-connected in the sense that the piston working chamber 16 of one linear actuator 14a and the piston rod working chamber 17 of the other linear actuator 14b are pressurized from a common first pressure line 18a. Accordingly, the piston rod working chamber 17 of one linear actuator 14a and the piston working chamber 16 of the other linear actuator 14b are pressurized from another common second pressure line 18b.

[0024] The hydraulic unit 12 is configured to be adjustable in flow rate. For this purpose, it has a variable-speed electric motor 19. And in addition, the hydraulic pump 20 of the hydraulic unit 12 is adjustable in the flow rate. Furthermore, hydraulic unit 12 is reversible, so that it can be operated with two flow delivery directions a, b.

[0025] The first pressure line 18a and a first outlet line 23a leading to a calming tank 22 both communicate with a first pump connection 21a of the hydraulic pump 20. A first flow throttle 24a is integrated in the first outlet line 23a. The same applies to the second pump connection 21b of the hydraulic pump 20, with which not only the second pressure line 18b and the second outlet line 23b communicate, but also a first suction line portion 25a connecting the second pump connection 21b of the hydraulic pump 20 with the calming tank 22, with an integrated check valve 26a. The same applies in turn to the first pump connection 21a of the hydraulic pump 20 by communicating with a second suction line portion 25b.

[0026] To actively bend the knee by moving the second skeletal structure 3 at the joint 2 relative to the first skeletal structure 1 in the direction of arrow , hydraulic unit 12 is operated with the first flow delivery direction a. As a result, both the piston working chamber 16 of one linear actuator 14a and the piston rod working chamber 17 of the other linear actuator 14b are pressurized via the first pressure line 18a, so that both the piston working chamber 16 of one linear actuator 14a and the piston rod working chamber 17 of the other linear actuator 14b form a first working chamber A in this sense. At the same time hydraulic fluid is displaced via the first outlet line 23a into the calming tank 22. That hydraulic fluid which is displaced from the piston rod working chamber 17 of one linear actuator 14a and the piston working chamber 16 of the other linear actuator 14b in accordance with the movement of the second skeleton structure 3 relative to the first skeleton structure 1, passes through the second pressure line 18b to the second pump connection 21b. In the illustrated embodiment of the exoskeleton, the quantity of hydraulic fluid displaced from actuator unit 11 via the second pressure line 18b essentially corresponds to that which is supplied to actuator unit 11 via the first pressure line 18a. Thus, in absence of a significant compensating flow (see above) the quantity of hydraulic fluid which the pump 20 sucks in at its second pump connection 21b via the first suction line portion 25a from the calming tank 22 essentially corresponds to the flow rate displaced into the calming tank 22 via the first outlet line 23a. A qualitatively appropriate pressurization takes place if the exoskeleton is to resist the stretching of the leg (arrow ) by means of the body's own muscles.

[0027] To dissipate the heat loss generated by the circulation of the hydraulic fluid through the outlet line 23a, which takes place permanently parallel to the pressurization of the working chamber A, the calming tank 22 has both internal ribs 27, which are washed around by the hydraulic fluid, and external cooling fins 28, which release the corresponding waste heat to the environment. The ribs 27 additionally ensure a maximum dwell time of the hydraulic fluid in the calming tank 22 by preventing a flow-related short circuit between the outlet line 23a and the suction line portion 25a. Also the ribs 27 prevent a flow-related short circuit by their arrangement in each case between the first outlet line 23a and the second suction line portion 25b or between the second outlet line 23b and the first suction line portion 25a in such a way that hydraulic fluid (correspondingly disturbed) which reaches the calming tank 22 through an outlet line 23 and the flow throttle 24 arranged therein can be immediately sucked in again via the adjacent suction line portion 25 when the flow delivery direction of the hydraulic unit 12 is reversed.

[0028] For reverse motion sequences, i.e. to actively stretch the knee using the exoskeleton (arrow ) or to resist bending the leg (arrow a) using the body's own muscles, hydraulic unit 12 is operated in reverse direction b. In this operating mode, both the piston rod working chamber 17 of one linear actuator 14a and the piston working chamber 16 of the other linear actuator 14b form a second working chamber B which acts in the opposite direction to the first working chamber A. In a modification, the two suction line portions 25a and 25b could be part of a suction line assembly comprising a common shuttle valve; in this case, the two check valves 26a and 26b would be omitted.

[0029] Unless otherwise stated in the following explanations, the above explanations apply accordingly to the second embodiment shown in FIG. 2 of the drawing. To avoid repetition, only the relevant differences are explained.

[0030] On the one hand, the actuator unit 11 here comprises only a single double-acting linear actuator 14, configures as a synchronized cylinder 29. Furthermore, instead of a reversible hydraulic unit, a non-reversible hydraulic unit 12 with a downstream flow reversing valve 30 is provided. A shut-off functionality is additionally integrated into the flow reversing valve 30, so that it also represents a shut-off valve 31 blocking both working chambers A and B. Furthermore, the flow throttle 24 integrated in the (only) outlet line 23 is adjustable. It should be emphasized that the differences between the embodiment shown in FIG. 2 and the embodiment shown in FIG. 1 do not depend on each other, so that they can be implemented independently of each other. For example, an actuator unit as shown in FIG. 1 can also be operated using the pressure supply unit illustrated in FIG. 2. Furthermore, instead of a combined valve unit, in which the flow reversing valve 30 and the shut-off valve 31 are combined, these two valves can also be installed separately and independently of each other.