WO2022216231A1

WO2022216231A1 - An apparatus for upper –limb motion assistance

Info

Publication number: WO2022216231A1
Application number: PCT/SG2022/050194
Authority: WO
Inventors: Ming Fung Thomas KWOK; Haoyong Yu
Original assignee: National University Of Singapore
Priority date: 2021-04-05
Filing date: 2022-04-05
Publication date: 2022-10-13
Also published as: CN114452157A

Abstract

The present application provides an apparatus for upper-limb motion assistance, which includes an elbow module, aligned, in use, with an elbow joint of the upper-limb and being configured to flex and extend with the elbow joint; a forearm module, held a forearm of the upper-limb and being configured to pronate and supinate the forearm; a driving assembly, cable-driven the elbow module and the forearm module, respectively; and a housing, separated from the elbow module and the forearm module, and configured for receiving the driving assembly therein.

Description

AN APPARATUS FOR UPPER -UIMB MOTION ASSISTANCE

TECHNICAU FIEUD

The present application relates to a portable and powered orthotic apparatus worn by a person with an impaired upper-limb, and more particularly to an apparatus for upper- limb motion assistance.

BACKGROUND

Today, millions of people suffer from stroke, neurological disorders, and muscle atrophy. Since most rehabilitation devices focus on clinic-based training, patients can only receive training or motion assistance in the clinics. However, patientsare unable to perform a daily task outside clinics. Thus, a portable assistive device like this present application is necessary for the patients to maximize their independence in activities of daily living (ADL).

This present application is a portable apparatus that aids the elbow and forearmin ADL. It provides two active degrees of freedom to assist in elbow flexion/extension andforearm pronation/supination indaily life.

SUMMARY

The present application is a portable apparatus that aids the elbow and forearm in activities of daily living (ADL) for people who suffer from a stroke, neurological disorders, or muscle atrophy.

The apparatus is configured toactively assist in two upper-limb motions: elbow flexion/extension and forearm pronation/supination. As for the apparatus frame, the length is adjustable for users with different body dimensions.

In an aspect of the present application, an apparatus for assisting movement of an upper-limb is provided, and the apparatus includes: an elbow module, aligned, in use, with an elbow joint of the upper-limb and being configured to flex and extend with the elbow joint; a forearm module, held a forearm of the upper-limb and being configured to pronate and supinate the forearm; a driving assembly, cable-driven the elbow module and the forearm module, respectively; and a housing, separated from the elbow module and the forearm module, and configured for receiving the driving assembly therein.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the elbow module includes: a first arm brace; a first link assembly, connected to the first arm brace, a second link assembly, connected with the first link assembly and able to rotate relative to the first link assembly; and a first cable-driven mechanism, connected at a joint between the first link assembly and the second link assembly, and configured to be driven by the driving assembly to drive the first link assembly rotating relative to the second link assembly.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the first link assembly includes: a first connecting link, an end of the first connecting link being connected to an end of the first arm brace; and a second connecting link, parallel to the first connecting link and an end of the second connecting link being connected to an opposite end of the first arm brace.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the second link assembly includes: a third connecting link, an end of the third connecting link being connected to an opposite end of the first connecting link; and a fourth connecting link, parallel to the third connecting link and an end of the fourth connecting link being connected to an opposite end of the second connecting link

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the first cable-driven mechanism includes: a wheel, aligned with the elbow joint and connected to the joint between the first link assembly and the second link assembly; and cables, connected between the driving assembly and the wheel; wherein the driving assembly drives the wheel through the cables to rotate to drive the first link assembly rotating relative to the second link assembly.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the first cable-driven mechanism further includes: a wheel supporting member, configured for supporting the wheel, the wheel supporting member is provided with a sheath fixing member, and the sheath fixing member is provided with sheaths configured for the cable sliding therein.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the forearm module is connected to the second link assembly.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the forearm module comprises: a circular guide rail, connected to the second link assembly; a connection member, slidably connected on the circular guide rail; a second arm brace, connected to the connection member; and a second cable-driven mechanism, configured for driving the connection member to slide along the circular guide rail through the driving assembly.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the second cable-driven mechanism includes: pulleys, connected to the second link assembly; and cables, passing through the connection member and connected between the driving assembly and the pulleys; wherein the driving assembly drives the pulleys through the cables to rotate to drive the second arm brace sliding along the circular guide rail.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the apparatus further includes: a third arm brace, connected to the circular guide rail with an extendable beam.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the driving assembly includes at least two actuators that drive the elbow module and the forearm module respectively.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the driving assembly includes a control unit, a power source, and a plate for holding all electronic components.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the housing is a backpack.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the apparatus further includes a sensor system comprising at least one motion, force, muscular, or neuronal sensor or marker for capturing human kinematic and dynamic movement data.

In addition to one or more of the features described above, or as an alternative to any of the foregoing embodiments, the sensor system is electrically connected to the driving assembly.

The embodiment of straps and fabric in the shoulder module is configured to hold the user’s shoulder and humerus in position and avoid shoulder sub luxation.

Since a cable-driven mechanism is applied, the actuators can be installed in any suitable location like a backpack, so that the apparatus’ inertia to impaired limb motion is reduced, and the users can move freely and comfortably with the apparatus. In actuators' preferred embodiment, series elastic actuators are used to achieve force control and compliant motion. Also, with actuators installed in the backpack, the apparatus becomes portablefor users to carry itaround and perform ADL tasks in various locations. Since the apparatus can serve as different roles, for instance, a human motion assistance provider wherein the apparatus assists the impaired upper-limb, and a human motion capture device wherein at least one sensor measures the upper-limb's real-time motion data to control actuators and evaluate users’ condition. The exemplary application for the apparatus includes unilateral rehabilitation and daily assistance.

BRIEF DESCRIPTION OF THE DRAWINGS

An exemplary embodiment of the present application is illustrated by way of example in the accompanying drawings in which like reference numbers indicate the same or similar elements and in which:

FIG. 1 is a diagrammatic representation of an exemplary apparatus for upper- limb motion assistance in which the present application may be employed;

FIG. 2 is a diagrammatic representation of an exemplary backpack in which the present application may be employed;

FIG. 3 is a diagrammatic representation of an exemplary attaching means for the forearm in which the present application may be employed;

FIG. 4 is a diagrammatic representation of another exemplary attaching means for the forearm and hand in which the present application may be employed; FIG. 5 is a diagrammatic representation of exemplary elbow and forearm modules of the apparatus in which the present application may be employed;

FIG. 6 is a diagrammatic representation of an exemplary cable-driven mechanism for elbow flexion/extension in which the present application may be employed;

FIG. 7 is a diagrammatic representation of an exemplary forearm module of the apparatus in which the present application may be employed;

FIG. 8 is a diagrammatic representation of an exemplary circular motion guide in the forearm module in which the present application may be employed;

FIG. 9 is a diagrammatic representation of an exemplary cable-driven mechanism for forearm pronation/supination in which the present application may be employed; and

FIG. 10 is a diagrammatic representation of exemplary sensors of apparatus in which the present application may be employed.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to make the purpose, the technical solution and the advantages of the present application be clearer and more understandable, the present application will be further described in detail below with reference to accompanying figures and embodiments. It should be understood that the specific embodiments described herein are merely intended to illustrate but not to limit the present application.

It is noted that when a component is referred to as being “fixed to” or “disposed on” another component, it can be directly or indirectly on another component. When a component is referred to as being “connected to” another component, it can be directly or indirectly connected to another component.

In the description of the present application, it needs to be understood that, directions or location relationships indicated by terms such as “length”, “width”, “up”, “down”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, and so on are the directions or location relationships shown in the accompanying figures, which are only intended to describe the present application conveniently and simplify the description, but not to indicate or imply that an indicated device or component must have specific locations or be constructed and manipulated according to specific locations; therefore, these terms shouldn’t be considered as any limitation to the present application.

In an embodiment of the present application, FIG.1 shows an embodiment of an exemplary apparatus for upper-limb motion assistance in which the present application may be employed. The apparatus assists the impaired upper-limb in elbow flexion/extension, and forearm pronation/supination with at least two actuators 301, 302 when operating. Exemplary applications for the apparatus include unilateral motion assistance in activities of daily living (ADL) and rehabilitation.

Since a cable-driven mechanism allows two actuators 301, 302 to be separated from the frame and installed in other suitable locations like a housing, in the present application, the housing is a backpack 3 that can be attached on the back of the users, so that the inertia of the apparatus to impaired limb motion is reduced, and users can move freely and comfortably with the apparatus. In a preferred embodiment of the actuators, series elastic actuators are used to achieve force control and compliant motion. Also, with actuators installed in a backpack 3 attached on the user’s back by two backpack straps 306, the apparatus becomes portable for users to carry it around and perform ADL tasks in various locations.

In the embodiment of the present application, the apparatus is provided with two modules: the elbow module for elbow flexion/extension, and the forearm module for forearm pronation/supination. The elbow module and the forearm module are connected and attached to the user’s body. As shown in FIG. 1, in the embodiment of the present application, the elbow module is attached to an upper arm with a first arm brace 101 and a first strap 102. Connected to arm brace 101, a fabric 104 with a set of three straps 103 is configured to pull the humerus head into the shoulder glenoid cavity to prevent shoulder joint dislocation. The forearm module is attached to a forearm with a second arm brace 501 and a second strap 502. Further, as for the apparatus frame, the length of the apparatus is adjustable for users with different body dimensions, specifically, a third arm brace 701 connected to a circular motion guide 4 with extendable beam 6 is attached to another forearm position with a third strap 702, so that when the user with a longer forearm, the third arm brace 701 can be used to assist the second arm brace 501 to hold the forearm, due to the extendable beam 6 can be extended according to the actual needs. Another embodiment of the third arm brace 701 will be presented in FIG. 4. When attaching the apparatus to the user’s body, a user can adjust the length of said extendable beam 6 by aligning different hole groups to fit his/her body dimension.

In the present application, the heavy actuators are separated from the apparatus and install them in other suitable locations, such as the backpack above mentioned, the apparatus’s inertia is reduced, and the impedance to impaired limb motion is reduced, and users can move freely and comfortably. Since actuators are separated from the apparatus, their size and weight will not affect the apparatus’s motion. Various actuation methods like electric, pneumatic, and hydraulic can be applied. In an embodiment of the present application, FIG. 2 is a diagrammatic representation of an exemplary backpack 3 in which the present application may be employed. The backpack 3 is contained with a driving assembly, and the driving assembly includes two actuators 301, 302 that respectively connect cables 202, 204, 403, 405, and the cables 202, 204, 403, 405 respectively pass through the cable sheaths 203, 205, 404, 406 mounted on the actuators 301, 302. Further, the driving assembly includes a control unit 303 configured for controlling the actuators 301, 302, a power source 304 configured for powering the actuators 301 , 302, and a plate 305 configured for holding all the electronic components.

FIG. 3 and 4 are diagrammatic representations of two exemplary attaching means for forearm or hand in which the present application may be employed. In one embodiment of the present application, as shown in FIG. 3, the third arm brace 701 is attached to the forearm with the third strap 702; in another embodiment of the present application, as shown in FIG. 4, a fourth arm brace 703 is attached to the forearm and hand with third and fourth straps 702, 704. Hence, the apparatus can apply two embodiments of the arm brace to fulfill different users’ needs: (1) the apparatus with the third arm brace 701 can support the forearm without limiting wrist motions, suitable for the users with intact wrists; and (2) the apparatus with the fourth arm brace 703can support the forearm and hand with fixing wrist motions, suitable for the users with an impaired wrist. In an embodiment of the present application, FIG. 5 is a diagrammatic representation of exemplary elbow and forearm modules of the apparatus in which the present application may be employed. The elbow module, aligning with the elbow joint, assists users in elbow flexion/extension. In one possible embodiment, the elbow module includes a first arm brace 101 used for supporting the upper arm, a first link assembly, connected to the first arm brace; and a second link assembly, connected with the first link assembly and able to rotate relative to the first link assembly. The first link assembly includes a first connecting link 207, an end of the first connecting link 207 being connected to an end of the first arm brace 101; and a second connecting link 208, parallel to the first connecting link 207 and an end of the second connecting link 208 being connected to an opposite end of the first arm brace 101. The second link assembly includes: a third connecting link 209, an end of the third connecting link 209 being connected to an opposite end of the first connecting link 207; and a fourth connecting link 210, parallel to the third connecting link 209 and an end of the fourth connecting link 210being connected to an opposite end of the second connecting link 208. Further, the elbow module includes a first cable-driven mechanism 2 aligned with the elbow, including a wheel 201 connected with two cables, a first sheath fixing member 206, and a third wheel supporting members 211. The wheel 201 is aligned with the elbow joint and connected to the joint between the first link assembly and the second link assembly; and the cables 202, 204 (shown in FIG. 6) are connected between the actuators and the wheel 201; and when the actuator contained in the backpack drives the wheel 201 through the cables 202, 204 to rotate, the first link assembly is rotated relative to the second link assembly to achieve elbow flexion/extension. The first connecting link 207, the second connecting link 208, the third connecting link 209, and the fourth connecting link 210 are formed a bilateral structure to transmit the assistive force firmer and smoother.

In the embodiment of the present application, FIG. 6 demonstrates a first cable- driven mechanism 2 in which the present may be employed. The first cable-driven mechanism 2 provides one active degree of freedom for elbow flexion/extension. The wheel 201 is configured to flex and extend the elbow joint with first and second cables 202, 204 sliding inside first and second sheaths 203, 205, driven by the actuator 301. A first sheath fixing member 206 with two sheath fixers is configured to fix the first and second sheaths 203, 205 so that the first and second cables 202, 204 can slide forward and backward without moving the first and second sheaths 203, 205.

In the embodiment of the present application, the first and second cables 202, 204 can also be a single cable.

In the embodiment of the present application, FIG. 7 is a diagrammatic representation of an exemplary forearm module of the apparatus in which the present application may be employed. The forearm module assists users in forearm pronation/ supination. In one possible embodiment, the forearm module is connected to the elbow module through third and fourth connecting links 209, 210. The forearm module further provides a second cable-driven mechanism 4, the second cable-driven mechanism 4 includes two sets of two pulleys 409, 410, a circular motion guide connected with third and fourth cables 403, 405, the circular motion guide is provide with a circular guide rail. The third and fourth cables 403, 405 are sliding inside the third and fourth sheaths 404, 406, and second and third sheath fixing members 407, 408 connected on the third and fourth connecting links 209, 210. The second and third sheath fixing members 407, 408 are configured to fix the third and fourth sheaths 404, 406 so that the third and fourth cables 403, 405 can slide forward and backward without moving the third and fourth sheaths 404, 406. Additionally, the forearm module has the second arm brace 501 attached to a circular guide rail 402.

In the embodiment of the present application, FIG. 8 is a diagrammatic representation of an exemplary circular motion guide in the forearm module in which the present application may be employed. Apart from the circular guide rail 402 attached to the third and fourth connecting links 209, 210, the second circular motion guide also consists of four rollers 401 and a connection member 411, shown in FIG. 8. The connection member 411 is configured to connecting the rollers 401 to the extendable beam 6 and slide along the circular guide rail 402.

As for actuation, FIG. 9 demonstrates the second cable-driven mechanism 4 in which the present application may be employed. The second cable-driven mechanism 4 provides one active degree of freedom for forearm pronation/ supination by pulling the connection member 411 through the third and fourth cables 403, 405. The dotted line in FIG. 9 represents the third and fourth cables 403, 405 inside the circular guide rail 402. When pulled by the third and fourth cables 403, 405, the connection member 411 slides along the circular guide rail 402 actively. Two sets of two pulleys 409, 410 are configured to change the driving direction of the third and fourth cable 403, 405 perpendicularly so that the third and fourth cables 403, 405 can be parallel to the user’s forearm.

Although the apparatus can work without sensors, FIG. 10 shows an embodiment of the apparatus with a sensor system electrically connected to the actuators, the sensor system may include at least one motion, force, muscular, or neuronal sensor or marker for capturing human kinematic and dynamic movement data. In an embodiment, an inertia measurement unit (IMU) 802 is mounted on the forearm, wherein the IMU captures the supper-limb motion for various purposes, such as, but not limited to, actuation control, patient evaluation, and virtual reality (VR) interaction. Also, an encoder 801 captures upper-limb motion for actuation control and other non-limiting purposes.

The aforementioned embodiments are only preferred embodiments of the present application, and should not be regarded as being limitation to the present application. Any modification, equivalent replacement, improvement, and so on, which are made within the spirit and the principle of the present application, should be included in the protection scope of the present application.

Claims

What is claimed is :

1. An apparatus for assisting movement of an upper-limb, comprising: an elbow module, aligned, in use, with an elbow joint of the upper-limb and being configured to flex and extend with the elbow joint; a forearm module, held a forearm of the upper-limb and being configured to pronate and supinate the forearm; a driving assembly, cable-driven the elbow module and the forearm module, respectively; and a housing, separated from the elbow module and the forearm module, and configured for receiving the driving assembly therein.

2. The apparatus for assisting movement of an upper-limb according to claim 1, characterized in that the elbow module comprises: a first arm brace; a first link assembly, connected to the first arm brace; a second link assembly, connected with the first link assembly and able to rotate relative to the first link assembly; and a first cable-driven mechanism, connected at a joint between the first link assembly and the second link assembly, and configured to be driven by the driving assembly to drive the first link assembly rotating relative to the second link assembly.

3. The apparatus for assisting movement of an upper-limb according to claim 2, characterized in that the first link assembly comprises: a first connecting link, an end of the first connecting link being connected to an end of the first arm brace; and a second connecting link, parallel to the first connecting link and an end of the second connecting link being connected to an opposite end of the first arm brace.

4. The apparatus for assisting movement of an upper-limb according to claim 3, characterized in that the second link assembly comprises: a third connecting link, an end of the third connecting link being connected to an opposite end of the first connecting link; and a fourth connecting link, parallel to the third connecting link and an end of the fourth connecting link being connected to an opposite end of the second connecting link.

5. The apparatus for assisting movement of an upper-limb according to claim 2, characterized in that the first cable-driven mechanism comprises: a wheel, aligned with the elbow joint and connected to the joint between the first link assembly and the second link assembly; and cables, connected between the driving assembly and the wheel; wherein the driving assembly drives the wheel through the cables to rotate to drive the first link assembly rotating relative to the second link assembly.

6. The apparatus for assisting movement of an upper-limb according to claim 5, characterized in that the first cable-driven mechanism further comprises: a wheel supporting member, configured for supporting the wheel, the wheel supporting member is provided with a sheath fixing member, and the sheath fixing member is provided with sheaths configured for the cable sliding therein.

7. The apparatus for assisting movement of an upper-limb according to claim 2, characterized in that the forearm module is connected to the second link assembly.

8. The apparatus for assisting movement of an upper-limb according to claim 7, characterized in that the forearm module comprises: a circular guide rail, connected to the second link assembly; a connection member, slidably connected on the circular guide rail; a second arm brace, connected to the connection member; and a second cable-driven mechanism, configured for driving the connection member to slide along the circular guide rail through the driving assembly.

9. The apparatus for assisting movement of an upper-limb according to claim 8, characterized in that the second cable-driven mechanism comprises: pulleys, connected to the second link assembly; and cables, passing through the connection member and connected between the driving assembly and the pulleys; wherein the driving assembly drives the pulleys through the cables to rotate to drive the second arm brace sliding along the circular guide rail.

10. The apparatus for assisting movement of an upper-limb according to claim 8 or 9, characterized in that the apparatus further comprises: a third arm brace, connected to the circular guide rail with an extendable beam.

11. The apparatus for assisting movement of an upper-limb according to any one of claims 1-10, characterized in that the driving assembly comprises at least two actuators that drive the elbow module and the forearm module respectively.

12. The apparatus for assisting movement of an upper-limb according to any one of claims 1-10, characterized in that the driving assembly comprises a control unit, a power source, and a plate for holding all electronic components.

13. The apparatus for assisting movement of an upper-limb according to any one of claims 1-10, characterized in that the housing is a backpack.

14. The apparatus for assisting movement of an upper-limb according to any one of claims 1-10, characterized in that the apparatus further comprises a sensor system comprising at least one motion, force, muscular, or neuronal sensor or marker for capturing human kinematic and dynamic movement data.

15. The apparatus for assisting movement of an upper- limb according to claim 14, characterized in that the sensor system is electrically connected to the driving assembly.