Wearable exoskeleton robot

Abstract

To provide a powered exoskeleton that can match the center of rotation thereof with the center of rotation of a wearer's joint, and simultaneously assist flexion and extension required for walking and abduction and adduction moments even by a single actuator so as to enable more natural walking assistance.SOLUTION: The powered exoskeleton comprises: a first fixing portion connected to a wearer's body; a first connecting portion rotatably connected to the first fixing portion; a second connecting portion arranged separated away from the first connecting portion and connected to the first connecting portion via a first link assembly; and a second fixing portion connected to a wearer's arm or leg and connected to the second connecting portion via a second link assembly.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an exoskeleton-type wearable robot that can assist walking more naturally by replacing the rotation joints in the outward and inward rotation directions with a spherical four-bar mechanism to align the center of rotation with the center of rotation of the wearer's joints, and by replacing the rotation joints in the bending and extension directions with a four-bar mechanism, it is possible to simultaneously assist the bending and extension and the abduction and adduction moments required for walking with only a single actuator. [Background technology]

[0002] The hip joint mechanism of existing exoskeleton robots is a type in which rotary joints are connected in series, so the center of rotation of the hip joint of the robot does not match the center of rotation of the wearer's hip joint, resulting in poor comfort and limited range of motion.

[0003] In addition, when only one driving machine is used, it is only possible to assist the moment in the flexion and extension directions, so there is a problem that it is not possible to simultaneously assist the abduction and adduction moments in addition to the flexion and extension necessary for walking.

[0004] In order to simultaneously assist the abduction and adduction moments, an additional actuator was required, but adding an actuator increased the weight of the robot, which reduced responsiveness and increased the burden on the wearer.

[0005] The matters described above as the background art are intended to enhance understanding of the background of the present invention, and should not be construed as corresponding to prior art already known to those skilled in the art. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent Publication No. 9610208B2 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been proposed to solve these problems, and aims to provide an exoskeleton-type wearable robot that can simultaneously assist the bending and extension and the abduction and adduction moments required for walking with only a single actuator by replacing the rotational joints in the outward and inward rotation directions with a spherical four-bar mechanism to align the center of rotation with the center of rotation of the wearer's joints, and by replacing the rotational joints in the bending and extension directions with a four-bar mechanism, it is possible to simultaneously assist the bending and extension and the abduction and adduction moments required for walking with only a single actuator, thereby providing a more natural walking assistance. [Means for solving the problem]

[0008] To achieve the above object, the exoskeleton-type wearable robot according to the present invention includes a first fixed part connected to a wearer's torso, a first connecting part rotatably connected to the first fixed part, a second connecting part disposed apart from the first connecting part and connected to the first connecting part via a first link assembly, and a second fixed part connected to the wearer's arm or leg and connected to the second connecting part via a second link assembly, and may be arranged such that the rotation centers of each connecting point connecting the first link assembly, the second connecting part and the second link assembly are directed toward the center of the wearer's joint.

[0009] The first fixed part is connected to the waist of the wearer, the second fixed part is connected to the thigh of the wearer, and the joint centre of the wearer can be the centre of the hip joint.

[0010] The first and second connecting portions and the multiple links constituting the first and second link assemblies may have a curved shape that is a part of a sphere surrounding the joint center of the wearer.

[0011] The first connecting part may be disposed behind the wearer, and one end may be rotatably connected to the rear surface of the first fixing part.

[0012] The first link assembly is comprised of a pair of links, and the first link assembly together with the first connecting portion and the second connecting portion can form a four-bar mechanism.

[0013] The second link assembly is composed of a pair of links, and the second link assembly, together with the second connecting portion and the second fixed portion, can form a four-bar mechanism.

[0014] The second connecting part may have one side connected to the first connecting part via a first link assembly and the other side connected to the second fixed part via a second link assembly.

[0015] The first connecting portion can be positioned behind the wearer, the second fastening portion can be positioned to the side of the wearer, and the second connecting portion can be positioned between the first connecting portion and the second fastening portion.

[0016] The instantaneous rotation axis of the first link assembly is a vertical axis extending vertically from the center of the wearer's joint, and internal and external rotation movements can be realized around the instantaneous rotation axis of the first link assembly.

[0017] The instantaneous axis of rotation of the second link assembly can be changed by abduction or adduction and flexion or extension movements.

[0018] The instantaneous axis of rotation of the second link assembly can be directed toward the wearer's joint center.

[0019] The first fixed part is connected to the wearer's waist, the second fixed part is connected to the wearer's thigh, the wearer's joint center is the center of the hip joint, and during the wearer's stance phase of walking, the instantaneous rotation axis of the second link assembly can change from a direction indicated by the sum of the abduction and extension movement components to a direction indicated by the sum of the adduction and flexion movement components.

[0020] An actuator is provided at a connection point connecting the first fixed part and the first connecting part, and the actuator can provide a rotational force to the first connecting part based on the first fixed part.

[0021] A rotation angle sensor may be provided at at least one of a plurality of connection points respectively connecting the first fixed portion, the first connecting portion, the first link assembly, the second connecting portion, the second link assembly, and the second fixed portion. Effect of the Invention

[0022] According to the exoskeleton-type wearable robot of the present invention, the rotational joints in the outward and inward rotation directions are replaced with a spherical four-bar mechanism, thereby aligning the center of rotation with the center of rotation of the wearer's joints, and the rotational joints in the flexion and extension directions are replaced with a four-bar mechanism, thereby simultaneously assisting the flexion and extension and the abduction and adduction moments required for walking with only a single actuator, thereby enabling more natural walking assistance. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view showing an exoskeleton-type wearable robot according to one embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged perspective view of an exoskeleton-type wearable robot according to one embodiment of the present invention. [Diagram 3] 11A to 11C are diagrams illustrating the external and internal rotation movements of an exoskeleton-type wearable robot according to one embodiment of the present invention. [Figure 4] 11A to 11C are diagrams illustrating the external and internal rotation movements of an exoskeleton-type wearable robot according to one embodiment of the present invention. [Diagram 5] 11A to 11C are diagrams illustrating the external and internal rotation movements of an exoskeleton-type wearable robot according to one embodiment of the present invention. [Figure 6] 13 is a graph showing a change in moment generated during the stance phase of walking of an exoskeleton-type wearable robot according to an embodiment of the present invention. [Figure 7] 13 is a graph showing a change in moment generated during the stance phase of walking of an exoskeleton-type wearable robot according to an embodiment of the present invention. [Figure 8] 13 is a graph showing a change in moment generated during the stance phase of walking of an exoskeleton-type wearable robot according to an embodiment of the present invention. [Figure 9]FIG. 13 is a diagram showing a change in moment generated during the stance phase of walking of an exoskeleton-type wearable robot according to one embodiment of the present invention. [Figure 10] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 11] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 12] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 13] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 14] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 15] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 16] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 17] 13A to 13C are diagrams illustrating the change in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking. [Figure 18] 13 is a graph showing a moment output during a stance phase of walking of an exoskeleton-type wearable robot according to an embodiment of the present invention. [Figure 19] 13 is a graph showing a moment output during a stance phase of walking of an exoskeleton-type wearable robot according to an embodiment of the present invention. [Figure 20] FIG. 2 is a diagram showing the size adjustment function of an exoskeleton-type wearable robot according to one embodiment of the present invention. [Figure 21] FIG. 2 is a diagram showing the size adjustment function of an exoskeleton-type wearable robot according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] FIG. 1 is a perspective view showing an exoskeleton-type wearable robot according to one embodiment of the present invention, FIG. 2 is an enlarged perspective view of the exoskeleton-type wearable robot according to one embodiment of the present invention, FIG. 3 to FIG. 5 are figures for explaining the external rotation and internal rotation movements of the exoskeleton-type wearable robot according to one embodiment of the present invention, FIG. 6 to FIG. 8 are graphs showing changes in moment generated during the stance phase of walking of the exoskeleton-type wearable robot according to one embodiment of the present invention, FIG. 9 is a figure showing changes in moment generated during the stance phase of walking of the exoskeleton-type wearable robot according to one embodiment of the present invention, FIG. 10 to FIG. 17 are figures explaining changes in the instantaneous rotation axis of the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention when walking, FIG. 18 and FIG. 19 are graphs showing moments output during the stance phase of walking of the exoskeleton-type wearable robot according to one embodiment of the present invention, and FIG. 20 and FIG. 21 are figures showing the size adjustment function of the exoskeleton-type wearable robot according to one embodiment of the present invention.

[0025] The exoskeleton-type wearable robot according to the present invention includes a first fixing part 100 connected to a wearer's torso, a first connecting part 200 rotatably connected to the first fixing part 100, a second connecting part 400 arranged apart from the first connecting part 200 and connected to the first connecting part 200 via a first link assembly 300, and a second fixing part 600 connected to the wearer's arm or leg and connected to the second connecting part 400 via a second link assembly 500, and the first link assembly 300, the second connecting part 400, and the second link assembly 500 may be arranged such that the rotation centers of the respective connecting points connecting the first link assembly 300, the second connecting part 400, and the second link assembly 500 are directed toward the center of the wearer's joint.

[0026] The present invention relates to an exoskeleton-type wearable robot, which forms a skeleton outside the wearer and supports the wearer's movements. Therefore, in the exoskeleton robot, it is important that the rotation center of the robot coincides with the rotation center of the wearer as much as possible. If the centers of wear do not coincide with each other, the wearer will feel a sense of strangeness and experience inconvenience.

[0027] Specifically, as shown in Fig. 1 and Fig. 2, the present invention can be attached to and driven by various parts of the wearer, and in particular, the first fixing part 100 is connected to the wearer's waist W via part 120, the second fixing part 600 is connected to the wearer's thigh L via part 620, and the wearer's joint center can be the center of the hip joint. As a result, it can be configured to support the wearer's leg L when the wearer walks, and fundamentally, it can support the movement of the wearer's hip joint.

[0028] Specifically, the first fixing part 100 is connected to the waist W of the wearer. By being fixed to the waist W of the wearer, the position of the first fixing part 100 is maintained even when the wearer walks. The first connecting part 200 is connected to the first fixing part 100. The first connecting part 200 is connected to the first fixing part 100 via a motor M, and when the motor M is driven, the first connecting part 200 rotates to assist the wearer in walking.

[0029] The first connecting part 200 is disposed at the rear of the wearer, and one end of the first connecting part 200 may be rotatably connected to the rear surface of the first fixing part 100. The first connecting parts 200 are disposed on the left and right sides, respectively, so that the left and right thighs can be supported independently.

[0030] A second connecting part 400 is provided at an end of the first connecting part 200, which is disposed apart from the first connecting part 200 and connected to the first connecting part 200 via a first link assembly 300. The second connecting part 400 is a bar type with a bent center, and as shown in the figure, one side is connected to the first link assembly 300 and the other side is connected to the second link assembly 500. The first link assembly 300 is composed of a pair of links 310, 320, and the first link assembly 300 can configure a four-bar mechanism together with the first connecting part 200 and the second connecting part 400. The second link assembly 500 is composed of a pair of links 510, 520, and the second link assembly 500 can configure a four-bar mechanism together with the second connecting part 400 and the second fixing part 600.

[0031] That is, the second connecting part 400 is connected to the first connecting part 200 and the second fixing part 600 via a four-bar mechanism. The second fixing part 600 is connected to the wearer's arm or leg, and is connected to the second connecting part 400 via the second link assembly 500. The rotation centers of the respective connection points connecting the first link assembly 300, the second connecting part 400, and the second link assembly 500 are arranged to face the joint centers of the wearer, so that the rotation center of the robot coincides with the rotation center of the wearer's joint, preventing the wearer from feeling a sense of strangeness when the robot moves.

[0032] Specifically, the first connecting part 200, the second connecting part 400, and the first link assembly 300, the second link assembly 500, may have a curved shape that is a part of a sphere surrounding the center of the wearer's joints. That is, each link and part is arranged on the curved surface of a sphere, and the shape is also formed as a curved surface surrounding the sphere, so that the rotation center of the actual robot is located at the rotation center of the wearer's joints.

[0033] Meanwhile, the second connecting part 400 may have one side connected to the first connecting part 200 via the first link assembly 300, and the other side connected to the second fixing part 600 via the second link assembly 500. The first connecting part 200 may be disposed behind the wearer, the second fixing part 600 may be disposed to the side of the wearer, and the second connecting part 400 may be disposed between the first connecting part 200 and the second fixing part 600.

[0034] In addition, the instantaneous rotation axis of the first link assembly 300 is a vertical axis X1 extending vertically from the center of the wearer's joint, and internal and external rotation movements can be implemented around the instantaneous rotation axis of the first link assembly 300. Figures 3 to 5 are views for explaining the external and internal rotation movements of the exoskeleton-type wearable robot according to an embodiment of the present invention.

[0035] 3 is a schematic diagram of the first four-bar mechanism formed by the first connecting part 200, the first link assembly 300, and the second connecting part 400. The first four-bar mechanism can be understood to be arranged on a spherical coordinate system, and can be conceptually represented as in FIG. 3. As shown in FIG. 3, the instantaneous movement of the second connecting part (link) 400 relative to the first connecting part (link) 200 can be understood to be a rotational movement based on an axis connecting the intersection of a curve on the sphere passing through the joints 304 and 301 and a curve on the sphere passing through the joints 303 and 302 to the center of the sphere. In other words, the first link assembly forms a four-bar mechanism, and this four-bar mechanism rotates on the sphere, ultimately realizing the external and internal rotation movements of the thigh L.

[0036] As shown in Fig. 4, the first four-bar mechanism formed by the first connecting part 200, the first link assembly 300 and the second connecting part 400 realizes the external and internal rotation motions rotating around the vertical axis X1. As a result, as shown in Fig. 5, the first link assembly 300 can perform the internal and external rotation motions of the hip joint while being located behind the buttocks of the wearer, so that it does not interfere with the rotation of the wearer's legs, reducing the sense of strangeness and increasing the range of motion (ROM).

[0037] 6 to 8 are graphs showing changes in moment generated during the stance phase of walking of an exoskeleton-type wearable robot according to an embodiment of the present invention. The human walking cycle is composed of a stance phase and a swing phase. During the stance phase, when the foot strikes the ground, the body receives a ground reaction force (GRF), so the moment generated by the muscles increases. Therefore, the robot of the present invention first presents a structure that can embody the direction of the hip joint moment required during the stance phase. FIGS. 6 to 8 show the hip joint moment required during the stance phase. As shown in FIG. 6, it can be seen that the abduction moment increases-decreases-increases-decreases during the stance phase. And as shown in FIG. 7, it can be seen that the extension-flexion-extension moment appears. It can also be seen that the moments of external rotation and internal rotation appear very small.

[0038] Putting these moment changes together, it can be seen that the rotation component value is very small, and the extension component value changes from + to - while the abduction component value remains +, as shown in Figure 9. In other words, the axis direction of the hip joint moment during the stance phase roughly changes within the plane where the extension / flexion axis and adduction / abduction axis are located, as shown in Figure 9, and moves from the middle of the abduction direction and extension direction to the middle of the abduction direction and flexion direction.

[0039] 10 to 17 are diagrams illustrating instantaneous changes in the rotation axis when the second link assembly of the exoskeleton-type wearable robot according to one embodiment of the present invention walks.

[0040] 10 and 11 show the case where the patient is extended 20 degrees backward, FIGS. 12 and 13 show the neutral state, FIGS. 14 and 15 show the case where the patient is bent 20 degrees forward, and FIGS. 16 and 17 show the case where the patient is bent 40 degrees forward.

[0041] The link of the second fixing part 600 and the link of the second connecting part 400 are connected via a spherical four-bar mechanism (joints 501, 502, 503, 504) having one degree of freedom. The instantaneous movement of the second fixing part 600 with respect to the second connecting part 400 can be understood as a rotational movement based on an axis X2 connecting the intersection of a curve on a sphere passing through the joints 501 and 502 and a curve on a sphere passing through the joints 504 and 503 to the center of the sphere, as shown in Figs. 10 and 11. Thus, as shown in Figs. 10 to 17, when the wearer performs a movement from extension to flexion, the instantaneous rotation axis of the second fixing part 600 with respect to the second connecting part 400 moves from between the adduction axis and the flexion axis to the direction of the flexion axis, and then moves between the flexion axis and the abduction axis.

[0042] 18 and 19 are graphs showing the moment output during the stance phase of the exoskeleton-type wearable robot according to an embodiment of the present invention, comparing the direction of the moment required during the stance phase with the direction of the output moment that the hip joint mechanism can apply to the wearer during the stance phase. FIG. 18 shows the φ value, which is the angle formed with the Z-axis direction when the moment direction is viewed in spherical coordinates, and FIG. 19 shows the θ value, which is the angle in the XY plane. In the graph, a is the output moment of the robot, and b is the moment required during the stance phase of the wearer. It can be seen that the angle between the output moment and the required moment matches well in the main middle part where the moment size is large. In particular, it can be seen that the φ value is related to the ratio of the abduction moment and the flexion moment among the moment components, and matches almost in the main section (20% to 90%). That is, it can be seen that the hip joint mechanism proposed here can realize a three-dimensional moment in the direction required for walking even if only a single actuator is used.

[0043] Accordingly, an actuator M is provided at a connection point connecting the first fixed part 100 and the first connecting part 200, and the actuator M can provide a rotational force to the first connecting part 200 based on the first fixed part 100. Such an actuator M can be exemplified by a motor, and even a single motor M can naturally express all of the abduction / adduction and flexion / extension movements and provide a support force for the wearer's walking. In addition, for the kinetic analysis and inverse kinematic analysis of each four-bar mechanism, each mechanism can be provided with a rotation angle sensor S1, S2 for measuring a link rotation angle. Thus, at least one of a plurality of connection points connecting the first fixed part 100, the first connecting part 200, the first link assembly 300, the second connecting part 400, the second link assembly 500, and the second fixed part 600 can be provided with a rotation angle sensor S1, S2.

[0044] 20 and 21 are diagrams showing the size adjustment function of an exoskeleton-type wearable robot according to an embodiment of the present invention. As shown in the figures, a pair of first connecting parts 200 are connected to the left and right of the fixing part, and the distance between each of the first connecting parts 200 can be adjusted by sliding the first connecting parts 200. This allows the lateral position adjustment of the first connecting part 200 and the motor M to fit the wearer's body shape. A second fixing part 600 is connected to the wearer's thigh L via a part 620, and the relative distance between the second fixing part 600 and the part 620 coupled to the wearer's thigh L can also be adjusted.

[0045] According to the exoskeleton-type wearable robot of the present invention, the rotational joints in the outward and inward rotation directions are replaced with a spherical four-bar mechanism, thereby aligning the center of rotation with the center of rotation of the wearer's joints, and the rotational joints in the flexion and extension directions are replaced with a four-bar mechanism, thereby simultaneously assisting the flexion and extension and the abduction and adduction moments required for walking with only a single actuator, thereby enabling more natural walking assistance.

[0046] While particular embodiments of the present invention have been shown and described, it will be apparent to those skilled in the art that various modifications and variations of the present invention can be made without departing from the spirit and scope of the present invention as defined by the following claims. [Explanation of symbols]

[0047] 100 1st fixed part 200 1st connection part 300 First link assembly 310, 320 Links 400 2nd connection part 500 Second link assembly 501, 502, 503, 504 Joints 510, 520 Link 600 2nd fixed part

Claims

1. A first fastening part that is connected to a wearer's torso; A first connecting portion rotatably connected to the first fixed portion; a second connecting portion disposed apart from the first connecting portion and connected to the first connecting portion via a first link assembly; a second fixed portion connected to an arm or leg of a wearer and connected to the second connecting portion via a second link assembly; The rotation centers of the connection points connecting the first link assembly, the second connection portion, and the second link assembly are arranged to face the joint center of the wearer, An exoskeleton-type wearable robot, characterized in that the first connecting portion and the second connecting portion, and the multiple links that constitute the first link assembly and the second link assembly, have a curved shape that is part of a sphere that surrounds the joint center of the wearer.

2. The exoskeleton-type wearable robot according to claim 1 , wherein the first fixed part is connected to the wearer's waist, the second fixed part is connected to the wearer's thigh, and the wearer's joint center is the center of the hip joint.

3. The exoskeleton-type wearable robot according to claim 1 , wherein the first connecting part is disposed behind the wearer, and one end of the first connecting part is rotatably connected to a rear surface of the first fixing part.

4. The exoskeleton-type wearable robot according to claim 1 , wherein the first link assembly is composed of a pair of links, and the first link assembly, together with the first connecting portion and the second connecting portion, constitutes a four-bar mechanism.

5. The exoskeleton-type wearable robot according to claim 1 , wherein the second link assembly is composed of a pair of links, and the second link assembly, together with the second connecting portion and the second fixed portion, constitutes a four-bar mechanism.

6. 2. The exoskeleton-type wearable robot according to claim 1, wherein one side of the second connecting part is connected to the first connecting part via a first link assembly and the other side is connected to the second fixed part via a second link assembly.

7. 2. The exoskeleton-type wearable robot according to claim 1, wherein the first connecting portion is disposed behind the wearer, the second fixing portion is disposed to the side of the wearer, and the second connecting portion is disposed between the first connecting portion and the second fixing portion.

8. 2. The exoskeleton-type wearable robot according to claim 1, wherein the rotation axis of the first link assembly is a vertical axis extending vertically from a joint center of the wearer, and internal and external rotation movements are realized around the rotation axis of the first link assembly.

9. The exoskeleton-type wearable robot according to claim 1 , wherein the rotation axis of the second link assembly is changed by abduction or adduction and flexion or extension movements.

10. The exoskeleton-type wearable robot according to claim 9 , wherein the rotation axis of the second link assembly is directed toward a joint center of the wearer.

11. 11. The exoskeleton wearable robot according to claim 10, wherein the first fixed part is connected to the wearer's waist, the second fixed part is connected to the wearer's thigh, the wearer's joint center is the center of the hip joint, and during the wearer's stance phase of walking, the rotation axis of the second link assembly changes from a direction indicated by the sum of abduction and extension movement components to a direction indicated by the sum of adduction and flexion movement components.

12. 2. The exoskeleton-type wearable robot according to claim 1, wherein an actuator is provided at a connection point connecting the first fixing part and the first connecting part, and the actuator provides a rotational force to the first connecting part based on the first fixing part.

13. 2. The exoskeleton wearable robot according to claim 1, wherein a rotation angle sensor is provided at at least one of a plurality of connection points respectively connecting the first fixed part, the first connecting part, the first link assembly, the second connecting part, the second link assembly, and the second fixed part.

Images