US20080096724A1

US20080096724A1 - Ankle rehabilitation apparatus

Info

Publication number: US20080096724A1
Application number: US11/768,659
Authority: US
Inventors: Ming-Shaung Ju; Chou-Ching Lin; Bo-Wei Pan
Original assignee: National Cheng Kung University NCKU
Current assignee: National Cheng Kung University NCKU
Priority date: 2006-10-24
Filing date: 2007-06-26
Publication date: 2008-04-24
Also published as: TWM311442U

Abstract

An ankle rehabilitation apparatus is disclosed. The ankle rehabilitation apparatus comprises a base, a rotary plate, a rotary plate, an actuator, a control unit, and a torque detector. The rotary plate is pivotally connected to the base to hold a user's ankle. The actuator has a driving shaft to rotate the base. The control unit is electrically connected to the actuator to control the actuator to rotate the rotary plate. The torque detector is electrically connected to the control unit to detect a torque exerted to the driving shaft, and outputting the torque signal according to the torque to the control unit.

Description

RELATED APPLICATIONS

This application claims priority to Taiwan Application Serial Number 95218794, filed Oct. 24, 2006, which is herein incorporated by reference.

FIELD OF THE INVENTION

This invention relates to an ankle rehabilitation apparatus, and more particularly, to an apparatus that guides the user's ankle to perform rehabilitation movements.

BACKGROUND OF THE INVENTION

From clinical experience, movement disorders due to hemiplegia include reduced range of motion (ROM), weakness, hyperactive reflexes, incoordination, spasticity, and synergy patterns. Patients' daily activities are affected since these disorders do not allow patients to voluntarily contract a single muscle group.
Conventionally, therapists would guide patients to perform continuously passive movements with their bare hands or with assistive equipment. When patients perform continuously active movements, therapists apply adequate resistance or assistance to induce normal synergies. However, in one period of rehabilitation, therapists have to take a lot of time to guide patients to perform a motion continuously and repeatedly. Therefore, conventional rehabilitation is very laborious and time-consuming. Further, therapists' assessments of the degree of rehabilitation are subjective, so that it is hard to objectively assess the degree of rehabilitation.
When conventional rehabilitation apparatus guides the patient's lower limbs to perform rehabilitation movements, for the stability of the rehabilitation, the conventional rehabilitation apparatus is combined with a chair in a single piece. Therefore, the weight and the size the conventional rehabilitation apparatus is very large, and the apparatus is therefore not portable. The patient can only perform rehabilitation movements in a specific location, such as a hospital.

SUMMARY OF THE INVENTION

Therefore, an aspect of the present invention is to provide the ankle rehabilitation apparatus to simulate the therapist's rehabilitation method and to continuously guide the user to perform the rehabilitation movements for a long time, thereby saving labor and time.
Another aspect of the present invention is to provide a portable ankle rehabilitation apparatus to perform rehabilitation movements in any location, and to be adjustable corresponding to the user's bodily form.
Another aspect of the present invention is to provide the ankle rehabilitation apparatus to continuously record the torque between the user's ankle and the apparatus in the rehabilitation process, so as to asses the degree of rehabilitation, thereby setting up an objective quantitative index for clinical rehabilitation assessment, and to amend the rehabilitation movements according to the degree of rehabilitation.
Another aspect of the present invention is to provide the ankle rehabilitation apparatus to the passive rehabilitation process or the active rehabilitation process, so as to raise the user's range of motion (ROM) and increase muscle strength, thereby reforming the user's movement disorders.
According to an embodiment of the present invention, the ankle rehabilitation apparatus comprises a base, a rotary plate, an actuator, a control unit, and a torque detector. The base has a holding frame, a first holder and a second holder, wherein the holding frame, the first holder and the second holder are adjustable corresponding to a user's bodily form, and the first holder holds the user's thigh, and the second holder holds the user's shank. The rotary plate is pivotally connected to the holding frame of the base, wherein the rotary plate has at least one holding member to hold the user's ankle. The actuator is mounted in a fixed position to the holding frame of the base, wherein the actuator has a driving shaft to rotate the rotary plate. The control unit is electrically connected to the actuator, wherein the control unit controls the actuator to rotate the rotary plate. The torque detector is disposed between the rotary plate and the actuator wherein the torque detector is electrically connected to the control unit to detect the torque exerted on the driving shaft and outputs a torque signal corresponding to the torque to the control unit.
Therefore, the ankle rehabilitation apparatus disclosed in the embodiments of the present invention can simulate the therapist's rehabilitation method and guide the user to perform the rehabilitation movements for a long time, thereby saving labor and time. The torque between the ankle and the actuator can be recorded to assess the degree of rehabilitation. The rehabilitation process of the ankle rehabilitation apparatus is determined by the degree of rehabilitation, thereby enhancing the rehabilitation effect. Further, the ankle rehabilitation apparatus of the present invention conveniently performs rehabilitation movements in any location, and can be adjusted to correspond to the shape of the user's body.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a side view showing the ankle rehabilitation apparatus according to a first embodiment of the present invention;

FIG. 2 is a three-dimensional view showing the ankle rehabilitation apparatus according to a first embodiment of the present invention;

FIG. 3 is a cross-sectional view showing the ankle rehabilitation apparatus according to a first embodiment of the present invention;

FIG. 4 is a partially exploded view showing the torque detector of the ankle rehabilitation apparatus according to a first embodiment of the present invention; and

FIG. 5 is the rehabilitation method flow diagram showing the torque detector of the ankle rehabilitation apparatus according to a first embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In order to make the illustration of the present invention more explicit and complete, the following description is stated with reference to FIG. 1 through FIG. 5.
Refer to FIG. 1. FIG. 1 is a side view showing the ankle rehabilitation apparatus according to a first embodiment of the present invention. The ankle rehabilitation apparatus comprises a base 100, a rotary plate 200, an actuator 300, a torque detector 400 and a control unit 500. The rotary plate 200 rotates relative to the base 100 and holds a user's ankle (such as a hemiplegia patient with movement disorders), so that the ankle can actively or passively perform reciprocating rotation in the rotary plate 200, thereby achieving rehabilitation effects. The actuator 300 provides rehabilitation resistance or assistance, thereby simulating the therapist's rehabilitation method. When users rotate their ankle for rehabilitation, the torque detector 400 detects a torque between the ankle and the actuator 300, and the degree of rehabilitation can be assessed objectively by the torque. The control unit 500 controls the actuator 300 to guide the user to perform the rehabilitation movements, and amends the actuation of the actuator 300 according to the degree of rehabilitation that is assessed by the torque detected. The ankle rehabilitation apparatus of the first embodiment is portable apparatus, thereby making it easier to perform rehabilitation movements at any location.
Refer to FIG. 2 and FIG. 3. FIG. 2 is a three-dimensional view showing the ankle rehabilitation apparatus according to a first embodiment of the present invention. FIG. 3 is a three-dimensional view showing a base of the ankle rehabilitation apparatus according to a first embodiment of the present invention. The base 100 of this embodiment may be a rectangular base, which can be combined with a chair to perform rehabilitation movements. The base 100 has a holding frame 110, a first holder 120, a second holder 130, a plurality of supporters 140 and a plurality of assembly holes 150. The holding frame 110 is laterally mounted to the base 100 and is positioned corresponding to the user's ankle, whereby the rotary plate 200 and the actuator 300 can be disposed thereon. The first holder 120 and the second holder 130 are mounted to the base 100 and are also positioned corresponding to the user's bodily form for holding the user's legs. For example, the first holder 120 can hold the user's thigh, and the second holder 130 can hold the user's shank. Therefore, when performing rehabilitation movements, the first holder 120 and the second holder 130 can securely hold the user's legs, thereby reducing the user's discomfort and promoting rehabilitation stability. Besides, the first holder 120 and the second holder 130 are adjustable corresponding to the user's bodily form, thereby making the rehabilitation convenient for the user. The supporters 140 are disposed below the base 100 to support the base 100. The heights of the supporters 140 are adjustable, thereby adjusting the height of the base 100 corresponding to the user's bodily form. The assembly holes 150 is disposed on the base 100, and may be a plurality of screw holes or notches for assembling the holding frame 110, the first holder 120 and the second holder 130 on the base 100. Therefore, the position of the holding frame 110, the first holder 120 and the second holder 130 can be adjusted to correspond to the shape of the user's body by means of the assembly holes 150.
Refer to FIG. 2 and FIG. 4. FIG. 4 is a partially exploded view showing the ankle rehabilitation apparatus according to an embodiment of the present invention. The rotary plate 200 of this embodiment is pivotally connected to the holding frame 110 of the base 100 and is adjusted to correspond to the shape of the user's body to hold the user's ankle. The rotary plate 200 has a holding member 210 and a supporting portion 220. The holding member 210 may be a holding belt to hold user's ankle. The supporting portion 220 is disposed according to the size of user's ankle. Therefore, when performing rehabilitation movements, user's ankle is held by the rotary plate 200, and then is rotated by the actuator 300, so as to perform rehabilitation movements.
Refer to FIG. 2 and FIG. 4 again. The actuator 300 of this embodiment is mounted in a fixed position on the holding frame 110 of the base 100 and is electrically connected to the control unit 500 and controlled by the control unit 500. The actuator 300 has a motor 310, a driving shaft 320 and a reset counter 330. One end of the driving shaft 320 is connected to the motor 310 and the other end thereof is connected to the rotary plate 200. Therefore, when the motor 310 of the actuator 300 operates, the motor 310 can rotate the rotary plate 200. The reset counter 330 has a curved rail 331 and a light breaker 332. The light breaker 332 is mounted to one end of the curved rail 331 and corresponds to the shape of the user's ankle, such as corresponding to the natural position thereof, thereby detecting if the rotary plate 200 returns to the initial status and counts the number of rounds that the rotary plate rotates to assess the degree of rehabilitation.
Refer to FIG. 4 again. The torque detector 400 of this embodiment is disposed between the rotary plate 200 and the actuator 300 and is electrically connected to the control unit 500, thereby detecting the torque applied to the driving shaft 320, and transmitting the torque signal to the control unit 500. The torque detector 400 has a plurality of ring portions 410, an isolation member 420 and a detecting circuit (not shown). The isolation member 420 may be made of engineering plastics and is disposed between the motor 310 and the torque detector 400 to isolate the signal noise therebetween.
In one embodiment of the present invention, the detecting circuit of the torque detector 400 is formed on the driving shaft 320. The detecting circuit may be a full bridge circuit formed by a plurality of strain gauges to detect the strain of the driving shaft 320 when the torsion is applied to the driving shaft 320, and to transmit a voltage signal to the control unit 500, so that the torque detector 400 can detect the torque.
Refer to FIG. 1 again. The control unit 500 of this embodiment may be a programmable control chip or computer apparatus. The control unit 500 can control the actuator 300 to rotate the rotary plate 200 in advance, so as to guide the user to perform the rehabilitation movements, or to amend the actuation of the actuator 300 according to the degree of rehabilitation that is assessed by the detected torque. The control unit 500 has a display 510 to display a trace point (not shown). The user can perform trajectory-tracking, thereby performing the rehabilitation movements actively according the trace point, thereby simulating the therapist's rehabilitation method.
Refer to FIG. 5. FIG. 5 is the rehabilitation method flow diagram showing a torque detector of the ankle rehabilitation apparatus according to a first embodiment of the present invention. The ankle rehabilitation apparatus of this embodiment may be portable to make performing rehabilitation movements convenient for the user and can perform a passive rehabilitation process or an active rehabilitation process. When performing the passive rehabilitation process, the user's ankle is relaxed and held by the rotary plate 200, and the first holder 120 and the second holder 130 can be adjusted to correspond to the user's bodily form, and the actuator 300 rotates the rotary plate 200, thereby guiding the user to perform the rehabilitation movements. First, the user's ankle is assessed, such as the largest full range of the joint and the muscle tone thereof, thereby determining if the ankle is allowed to perform the rehabilitation movements, the rehabilitation process and the largest angle the rotary plate 200 can be rotated, such as the largest dorsiflexion or the plantarflexion angle the user can tolerate. Then, the actuator 300 rotates the rotary plate 200 smoothly and repeatedly. The angle the rotary plate 200 rotates is increased gradually, such as a predetermined angle for the increment is increased. When the rotating angle of the rotary plate 200 meets the maximum rotating angle, the rotary plate 200 maintains the status for 5 seconds. Then, the rotary plate 200 returns to the initial position and repeats the foregoing rehabilitation process. In the passive rehabilitation process, the torque detector 400 continuously detects the torque to assess the passive rigidity and the muscle tone of the ankle, thereby determining if the rehabilitation process guided by the ankle rehabilitation apparatus is improper, and protects the user from damage or injury. Therefore, the ankle rehabilitation apparatus of the present invention can simulate the therapist's rehabilitation method to increase the user's range of motion (ROM) and to reduce the passive rigidity and the muscle tone of the ankle.
Refer to FIG. 1 again. When performing the active rehabilitation process, the display 510 of the control unit 500 displays the trace point, and the user can actively rotate the rotary plate 200 to follow the trace point. In the active rehabilitation process, the actuator 300 applies resistance or assistance torque to the user's ankle, namely the rotating direction of the actuator 300 is the same as or different to the rotating direction of the user's ankle, thereby assisting or resisting the ankle to rotate. Therefore, the strength of the ankle can be raised by the active rehabilitation process, and further the user's movement disorder is reformed.
Therefore, the ankle rehabilitation apparatus can simulate the therapist's rehabilitation method and guide the user to perform rehabilitation movements for a long time, thereby saving labor and time, and the torque between the ankle and the actuator can be recorded to assess the degree of rehabilitation, thereby setting up an objective quantitative index for clinical rehabilitation assessment. The ankle rehabilitation apparatus can perform passive rehabilitation or active rehabilitation that is determined by the degree of rehabilitation, thereby promoting the rehabilitation effect. Further, The ankle rehabilitation apparatus of the present invention is portable and conveniently performs rehabilitation movements in any location, and can be adjusted to correspond to the user's body shape.
As is understood by a person skilled in the art, the foregoing embodiments of the present invention are strengths of the present invention rather than limiting of the present invention. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structure.

Claims

1. An ankle rehabilitation apparatus, comprising:

a base having a holding frame, a first holder and a second holder, wherein the holding frame, the first holder and the second holder are adjustable corresponding to a user's bodily form, and the first holder holds the user's thigh, and the second holder holds the user's shank;

a rotary plate pivotally connected to the holding frame of the base, wherein the rotary plate has at least one holding member to hold the user's ankle;

an actuator fixedly mounted to the holding frame of the base, wherein the actuator has a driving shaft for rotating the rotary plate;

a control unit electrically connected to the actuator, wherein the control unit controls the actuator to rotate the rotary plate;

a torque detector disposed between the rotary plate and the actuator wherein the torque detector is electrically connected to the control unit to detect the torque exerted on the driving shaft and outputting a torque signal corresponding to the torque to the control unit.

2. The ankle rehabilitation apparatus as claimed in claim 1, wherein the base has a plurality of assembly holes for assembling the holding frame and the holder on the base.

3. The ankle rehabilitation apparatus as claimed in claim 1, wherein the holding member is a holding belt.

4. The ankle rehabilitation apparatus as claimed in claim 1, wherein the actuator further has a motor to rotate the driving shaft.

5. The ankle rehabilitation apparatus as claimed in claim 4, wherein the torque detector has an isolation member disposed between the motor and the torque detector to isolate the signal noise there between.

6. The ankle rehabilitation apparatus as claimed in claim 1, further comprising:

a reset counter to detect if the rotary plate returns to the initial status and count the number of rounds that the rotary plate rotates.

7. The ankle rehabilitation apparatus as claimed in claim 6, wherein the reset counter includes a light breaker disposed and arranged corresponding to the user' ankle.

8. The ankle rehabilitation apparatus as claimed in claim 1, wherein the torque detector is disposed on the outer peripheral of the driving shaft.

9. The ankle rehabilitation apparatus as claimed in claim 1, wherein the control unit is a computer apparatus.

10. The ankle rehabilitation apparatus as claimed in claim 1, wherein the control unit is a programmable control chip.

11. The ankle rehabilitation apparatus as claimed in claim 1, wherein the control unit controls the actuation of the actuator according to the torque exerted on the driving shaft.

12. The ankle rehabilitation apparatus as claimed in claim 1, further comprising;

a display to display a trace point adapted to be tracked by a user to perform a trajectory tracking task.