JP5737191B2 - Biological motion assist device, control method thereof, and control program - Google Patents

Description

  The present invention relates to a biological operation assisting device that assists the operation of a joint portion of a living body such as a human, a control method thereof, and a control program.

  In recent years, various devices have been developed for the purpose of reducing human movements. For example, a mechanism is known in which a splint is attached to a joint part of a human body and the rotation range of the splint is adjustable (see Patent Document 1).

JP-T-08-511975

  However, in the mechanism shown in Patent Document 1, for example, when the splint stops moving, the user cannot determine whether the splint does not move beyond its movable range or whether it moves due to a catch or the like. It is difficult to clearly recognize the movable range.

  The present invention has been made to solve such problems, and a main object of the present invention is to provide a biological movement assist device that can clearly recognize the movable range of the joint, a control method thereof, and a control program. .

In one aspect of the present invention for achieving the above object, a link mechanism that rotatably supports a joint part of a living body, a drive unit that drives the link mechanism to assist the operation of the joint part of the living body, A biological motion assisting device comprising: an angle detection unit that detects a rotation angle of a joint unit; and a control unit that controls the drive unit based on the rotation angle of the joint unit detected by the angle detection unit. The control means controls to vary the driving torque of the driving means when it is determined that the rotation angle of the joint part is out of a predetermined range based on the rotation angle detected by the angle detection means. This is a biological operation assisting device.
In this aspect, when the control unit determines that the rotation angle of the joint portion is out of a predetermined range based on the rotation angle detected by the angle detection unit, the control unit increases the driving torque of the driving unit, When it is determined that the rotation angle of the joint portion has returned within a predetermined range based on the rotation angle detected by the angle detection means, the drive torque of the drive means may be reduced.
In this aspect, when the control means determines that the rotation angle of the joint portion is out of a predetermined range based on the rotation angle detected by the angle detection means, the drive is performed so that the joint portion vibrates. The driving torque of the means may be controlled.
In this aspect, a changing unit that changes the predetermined range may be further provided.
In this aspect, the link mechanism includes a self-locking mechanism that locks the operation of the joint when the rotation angle of the joint reaches a predetermined angle, and the predetermined range is in the vicinity of the predetermined angle. It may be set to a value smaller than the predetermined angle.
In this aspect, the joint portion is a human knee joint portion, and the link mechanism has a first link whose upper end side is fixed to the thigh and an upper end side rotatable to the lower end side of the first link. A second link that is connected and has a lower end fixed to the lower leg, a third link that is rotatably connected to the lower end of the first link, and an upper end that is rotatable to the lower end of the third link And a fourth link that is rotatably connected to the second link at a lower end side.
In this one aspect, when the control unit determines that the rotation angle of the knee joint part is out of a predetermined range based on the knee joint angle detected by the angle detection unit during walking training of the user, You may control so that the drive torque of a drive means is fluctuated.
On the other hand, according to one aspect of the present invention for achieving the above object, a link mechanism that rotatably supports a joint part of a living body, and a driving unit that drives the link mechanism to assist the operation of the joint part of the living body. And a step of detecting the rotation angle of the joint part, and based on the detected rotation angle, it is determined that the rotation angle of the joint part is out of a predetermined range. And a step of controlling the driving means to vary the driving torque of the driving means.
In this one aspect, when it is determined that the rotation angle of the joint portion is out of a predetermined range based on the detected rotation angle, the driving torque of the driving unit is increased, and based on the detected rotation angle. When it is determined that the rotation angle of the joint has returned within a predetermined range, the driving torque of the driving means may be reduced.
In this aspect, when it is determined that the rotation angle of the joint portion is out of a predetermined range based on the detected rotation angle, the driving torque of the driving means is controlled so that the joint portion vibrates. Good.
Furthermore, according to one aspect of the present invention for achieving the above object, a link mechanism that rotatably supports a joint portion of a living body, and a driving unit that drives the link mechanism to assist the operation of the joint portion of the living body. A control program for a biological motion assisting device comprising: when the rotation angle of the joint portion is determined to be out of a predetermined range based on the rotation angle of the joint portion; The control program of the biological motion assisting device may be characterized by causing a computer to execute the control process as described above.

  ADVANTAGE OF THE INVENTION According to this invention, the biological body movement assistance apparatus which can recognize the movable range of a joint part clearly, its control method, and a control program can be provided.

It is a block diagram which shows the schematic system configuration | structure of the biological movement assistance apparatus which concerns on Embodiment 1 of this invention. It is a flowchart which shows the control method by the biological movement assistance apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the relationship between a knee joint angle and a knee joint torque command value. It is a figure which shows typically the vibration operation | movement of a user's leg part. It is a figure which shows the link mechanism with which the user's leg part was mounted | worn. (A) It is a figure which shows the operation state of a link mechanism. (B) It is a figure which shows the operation state of a link mechanism. (C) It is a figure which shows the operation state of a link mechanism. (D) It is a figure which shows the operation state of a link mechanism. (E) It is a figure which shows the operation state of a link mechanism. It is a figure which shows the lock state of a link mechanism. It is a figure which shows typically the vibration operation | movement of a user's leg part. It is a figure which shows an example of the user's walking motion during walking training. It is a figure which shows typically the vibration operation | movement of a user's leg part.

Embodiment 1 FIG.
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing a schematic system configuration of the biological movement assist device according to the first embodiment of the present invention. The biological motion assisting device 1 according to Embodiment 1 of the present invention includes, for example, a joint part (a knee joint part, a hip joint part, an ankle joint part, an elbow joint part, a shoulder joint part, a wrist joint) of a human body such as a physically handicapped person. And has a function of assisting the operation of the joint, and allows the wearer to experience and recognize the movable range of the joint.

  The biological motion assist device 1 according to the first embodiment includes, for example, a link mechanism 2 that is attached to a user's leg and rotatably supports the knee joint of the leg, and an angle sensor 3 that detects a knee joint angle. And an actuator 4 that drives the link mechanism 2 to assist the operation of the knee joint, and a controller 5 that controls the actuator 4.

  The link mechanism 2 is configured such that a plurality of links are connected to each other, fixed to the user's thigh and crus, and linked to the operation of the thigh and crus to support the knee joint. ing.

  The angle sensor 3 is composed of, for example, a potentiometer or a rotary encoder, and is provided in the link mechanism 2 to detect the knee joint angle by detecting the rotation angle of each link. The angle sensor 3 is connected to the control unit 5 and outputs the detected knee joint angle to the control unit 5.

  The actuator 4 is constituted by a servo motor, for example, and is connected to the link mechanism 2. The actuator 4 assists the operation of the knee joint by driving the link mechanism 2 in accordance with a control signal output from the control unit 5.

  The control unit 5 calculates a knee joint torque command value for driving the knee joint portion based on the knee joint angle output from the angle sensor 3, and outputs a control signal corresponding to the calculated knee joint torque command value to a drive circuit. Output to the actuator 4 via 6. The control unit 5 includes, for example, a CPU (Central Processing Unit) 5a that performs control processing, arithmetic processing, and the like, a ROM (Read Only Memory) 5b that stores a control program executed by the CPU 5a, an arithmetic program, and the like, processing data The hardware configuration is centered on a microcomputer composed of a RAM 5c or the like for storing the information. The CPU 5a, ROM 5b, and RAM 5c are connected to each other via, for example, a bus 5d.

  In addition to the knee joint angle output from the angle sensor 3, the control unit 5 includes, for example, pressure information output from a pressure sensor provided on the sole of the user's leg, or provided on the user's leg. The actuator 4 may be controlled using myoelectric information output from the obtained myoelectric sensor.

  By the way, in the conventional biological motion assisting device, when the joint portion does not move, the user does not know whether the joint portion does not move beyond the movable range or does not move due to a catch or the like. It has become difficult to recognize clearly.

  Therefore, in the biological motion assisting device 1 according to the first embodiment, the control unit 5 makes the knee joint angle equal to or greater than the first predetermined angle indicating the movable range restriction based on the knee joint angle output from the angle sensor 3. Thus, when it is determined that it is out of the predetermined range, the drive torque of the actuator 4 is controlled to fluctuate to vibrate the knee joint. Thereby, the user can experience that the knee joint angle has deviated from the predetermined range due to the vibration, and can recognize it reliably.

  FIG. 2 is a flowchart showing a control method by the biological motion assisting device according to the first embodiment.

For example, (a) the control unit 5, when the knee joint angle phi from the angle sensor 3 is determined to have become the first predetermined angle or more phi _alpha (YES in step S101), the following equation (1) of the gain alpha and / Alternatively, by changing the constant β (step S102), the knee joint torque command value τ _α (φ) is rapidly increased (step S103) (FIG. 3).
τ _α (φ) = α · τ (φ) + β (φ ≧ φ _α ) (1) In the above equation (1), α is a gain and β is a constant.

As described above, increases the driving torque by causing rapid increase knee joint torque command value, since the knee joint is pushed back (step S104), and the knee joint angle is returned within a first predetermined angle phi _alpha ( FIG. 4).

(B) the controller 5 when the knee angle phi is determined that returned within a first predetermined angle phi _alpha (YES in step S105), the equation (1) of the gain alpha and / or constants β original value By returning to (step S106), the knee joint torque command value is decreased (step S107). Thereby, the drive torque with respect to a user's knee joint part reduces, and the force which pushes back a knee joint part becomes weak. For this reason, when the user applies a force to the knee joint, the knee joint angle φ becomes equal to or larger than the first predetermined angle φ _α again.

By repeating the above (a) and (b), so that the knee joint by the first predetermined angle phi _alpha to the boundary vibrates. As a result, the user can experience the first predetermined angle φ _α indicating the movable range limitation of the knee joint, and can clearly recognize the movable range.

In the above embodiment, the control unit 5, when the knee joint angle phi from the angle sensor 3 is determined to have become the first predetermined angle or more phi _alpha, an example of a control for varying the driving torque of the actuator 4 Description However, it is not limited to this. For example, the control unit 5, when the knee joint angle phi from the angle sensor 3 is determined to have become the first predetermined angle or more phi _alpha, sharply increases the gain of the PID control, destabilizing to intentionally diverge Thus, the knee joint may be vibrated. Further, when the control unit 5 determines that the knee joint angle φ is equal to or greater than the first predetermined angle φ _α , the control unit 5 intentionally diverges and destabilizes the PID control by giving an arbitrary disturbance, so that the knee The joint part may be vibrated or may be vibrated using any control method.

Further, the gain α, the constant β, and the first predetermined angle φ _α in the above equation (1) can be arbitrarily set and changed by the user via the input device 7 (one specific example of the changing unit). Thereby, the user can experience and recognize the limitation of the movable range of the knee joint more clearly by setting the gain α and the constant β optimally. Furthermore, the user, via the input device 7, by setting the first predetermined angle phi _alpha optimally, it is possible to set the movable range restriction in response to the knee joint of the user.

In the first embodiment, the case where the biological motion assisting device 1 is applied to the knee joint has been described. However, other living bodies such as the hip joint, the ankle joint, the elbow joint, the shoulder joint, and the wrist joint can be used. In the case of applying to the joint part, it can be applied in the same manner as the knee joint part. Further, when the control unit 5 determines that the knee joint angle φ output from the angle sensor 3 is equal to or _larger than the first predetermined angle φ _α or equal to or smaller than the third predetermined angle φ _β and is out of the predetermined range, the driving of the actuator 4 is performed. The knee joint may be vibrated by controlling the torque to vary.

  As described above, in the biological motion assisting device 1 according to the first embodiment, the control unit 5 is based on the knee joint angle output from the angle sensor 3 so that the knee joint angle is equal to or greater than the first predetermined angle indicating the movable range limitation. Thus, when it is determined that it is out of the predetermined range, the drive torque of the actuator 4 is controlled to fluctuate to vibrate the knee joint. Thereby, the user can feel that the knee joint angle has deviated from the predetermined range due to the vibration, and can recognize the movable range. That is, the user can clearly recognize the movable range of the joint. In addition, by vibrating as described above, only the user wearing the biological movement assisting device 1 can recognize that the knee joint angle is out of the predetermined range. Simultaneously with the above vibration, a warning sound may be output or a warning light may be turned on.

Embodiment 2. FIG.
In the biological motion assist device 1 according to Embodiment 2 of the present invention, the link mechanism 2 includes a first link 21 whose upper end is fixed to the thigh 101 and an upper end that is rotatable to the lower end of the first link 21. The second link 22 is connected and the lower end is fixed to the lower leg 102, the third link 23 is connected to the lower end of the first link 21 so that the upper end is rotatable, and the upper end is connected to the lower end of the third link 23. It is configured as a four-joint link mechanism having a fourth link 24 that is rotatably connected to the second link 22 and has a lower end that is rotatably connected to the second link 22 (FIG. 5).

6A to 6E are diagrams illustrating an example of the operating state of the link mechanism 2. FIG.
For example, when the knee joint portion 103 is gradually bent counterclockwise from the extended state (a) of the knee joint portion 103, the second link 22 also gradually rotates counterclockwise in accordance with the rotation of the lower leg portion 102. ((B), (c), (d), (e)). In conjunction with the rotation of the second link 22, the connecting portions of the third and fourth links 23 and 24 are gradually bent outward.

  The link mechanism 2 includes a self-locking mechanism that locks the operation of the knee joint portion 103 when the knee joint angle reaches the second predetermined angle. When the link mechanism 2 is in the locked state, as shown in FIG. 7, the third and fourth links 23 and 24 are self-locked in a straight state.

  Here, for example, in a state where the user is sitting on a chair or the like, the knee joint portion 103 of the leg portion is extended, the knee joint angle becomes the second predetermined angle, and the lock state of the link mechanism 2 as described above can occur. I want to avoid as much as possible.

Accordingly, the living body motion assisting apparatus 1 according to the second embodiment, the first predetermined angle phi _alpha, for example, to prevent the locked state of the link mechanism 2 described above, than the second predetermined angle at a second predetermined angle near A small value is set (FIG. 8). Here, the first predetermined angle φα is set to a value slightly smaller than, for example, a knee joint angle of 120 degrees when the link mechanism 2 is locked. Then, the control unit 5, based on the knee joint angle phi outputted from the angle sensor 3, when the knee joint angle phi is determined to become the first predetermined angle or more phi _alpha, to vary the driving torque of the actuator 4 And the knee joint 103 is vibrated.

As a result, even when the user extends the leg, vibration is generated at the first predetermined angle φ _α before the link mechanism 2 is locked (second predetermined angle), and the link mechanism 2 is locked. You can feel and be sure to recognize that there is a possibility of becoming. Therefore, the user can reliably avoid the locked state before the link mechanism 2 is locked.

Embodiment 3 FIG.
The biological movement assistance device 1 according to Embodiment 3 of the present invention is applied to user walking training. For example, as shown in FIG. 9, when a user performs walking training using a conventional biological motion assisting device, the timing is not good and the knee joint is bent and the foot of the leg is bent. Frequently happens to land. In this case, there is a possibility that the user loses balance due to knee breakage.

Therefore, in the biological motion assisting apparatus 1 according to the third embodiment, the control unit 5 determines that the knee joint angle φ is the first based on the knee joint angle φ output from the angle sensor 3 during the user's walking training. It becomes more than a predetermined angle phi _alpha, when it is determined that out of a predetermined range, performs control so as to vary the driving torque of the actuator 4 (Fig. 10). Here, the first predetermined angle phi _alpha, for example, is set to a slightly smaller value than the knee joint angle 20-30 degrees commonly knee bending occurs.

  Accordingly, the user can quickly detect the state of the knee break during walking training and prevent the balance from being lost. In addition, the control part 5 can judge that a user is under walking training based on the output signal from a mode switch etc., for example.

Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.
In the above-described embodiments, the present invention has been described as a hardware configuration, but the present invention is not limited to this. In the present invention, for example, the processing executed by the control unit 5 can be realized by causing the CPU 5a to execute a computer program.

  The program may be stored using various types of non-transitory computer readable media and supplied to a computer. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer readable media are magnetic recording media (eg flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg magneto-optical disks), CD-ROM, CD-R, CD-R / W. Semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM).

  The program may be supplied to the computer by various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

DESCRIPTION OF SYMBOLS 1 Biological operation | movement assistance apparatus 2 Link mechanism 3 Angle sensor 4 Actuator 5 Control part 6 Drive circuit 7 Input device 21 1st link 22 2nd link 23 3rd link 24 4th link

Claims (9)

A first link having an upper end fixed to a part of the living body, and a second link having an upper end rotatably connected to the lower end side of the first link and a lower end fixed to the other part of the living body. A link mechanism for rotatably supporting the joints of
Drive means for driving the link mechanism to assist the operation of the joint portion of the living body;
An angle detection means for detecting a rotation angle between the first link and the second link ;
A biological motion assisting device comprising: control means for controlling the drive means based on the rotation angle detected by the angle detection means;
When the control means determines that the rotation angle is equal to or greater than the first predetermined angle based on the rotation angle detected by the angle detection means, the control means returns the rotation angle to the first predetermined angle or less. performs control of increasing the driving torque of the driving means, or performs control for vibrating the driving torque of said driving means,
A biological motion assisting device. The biological movement assist device according to claim 1,
The control means includes
When it is determined that the rotation angle is equal to or greater than a first predetermined angle based on the rotation angle detected by the angle detection means, the drive torque of the drive means is increased,
When it is determined that the rotation angle is smaller than a first predetermined angle based on the rotation angle detected by the angle detection unit, the driving torque of the driving unit is decreased.
A biological motion assisting device. The biological movement assist device according to claim 1 or 2 ,
A biological movement assisting device further comprising changing means for changing the first predetermined angle . The biological movement assist device according to any one of claims 1 to 3 ,
The link mechanism has a third link whose upper end side is rotatably connected to the lower end side of the first link, an upper end side is rotatably connected to the lower end side of the third link, and the lower end side rotates to the second link A fourth link that can be connected, and when the rotation angle of the joint portion reaches a second predetermined angle , the third link and the fourth link are self-locked, thereby Includes a self-locking mechanism that locks the operation,
The biological motion assisting device, wherein the first predetermined angle is set to a value smaller than the second predetermined angle . The biological movement assist device according to claim 4 ,
The joint is a human knee joint;
The link mechanism includes a first link whose upper end is fixed to the thigh, a second link whose upper end is rotatably connected to the lower end of the first link, and whose lower end is fixed to the lower leg, A third link whose upper end is rotatably connected to the lower end of the first link, and an upper end which is rotatably connected to the lower end of the third link, and a lower end which is rotatably connected to the second link. A living body motion assisting device comprising four links. The biological movement assist device according to any one of claims 1 to 5 ,
When the control unit determines that the rotation angle is equal to or greater than a first predetermined angle based on the rotation angle detected by the angle detection unit during a user's walking training, the control unit calculates a drive torque of the drive unit. Control to fluctuate,
A biological motion assisting device. A first link having an upper end fixed to a part of the living body, and a second link having an upper end rotatably connected to the lower end side of the first link and a lower end fixed to the other part of the living body. A biological movement assisting device comprising: a link mechanism that rotatably supports the joint part; and a driving unit that drives the link mechanism and assists the movement of the joint part of the biological body,
Detecting a rotation angle between the first link and the second link ;
Based on the detected rotation angle, when it is determined that the rotation angle is equal to or greater than a first predetermined angle, the drive torque of the driving means is increased so as to return the rotation angle to within the first predetermined angle. Or control to vibrate the driving torque of the driving means ,
Steps,
A control method for a biological motion assisting device, comprising: It is a control method of the living body operation auxiliary device according to claim 7 ,
Based on the detected rotation angle, when it is determined that the rotation angle is equal to or greater than a first predetermined angle , the driving torque of the driving means is increased,
When it is determined that the rotation angle is smaller than a first predetermined angle based on the detected rotation angle, the driving torque of the driving means is decreased.
A control method for a biological movement assist device. A first link having an upper end fixed to a part of the living body, and a second link having an upper end rotatably connected to the lower end side of the first link and a lower end fixed to the other part of the living body. A control program for a biological motion assisting device comprising: a link mechanism that rotatably supports the joint portion; and a drive unit that drives the link mechanism to assist the operation of the joint portion of the biological body,
Based on the rotation angle between the first link and the second link, when it is determined that the rotation angle is equal to or greater than a first predetermined angle, the drive means is configured to return the rotation angle to be within the first predetermined angle. A process of increasing the driving torque of the driving means, or performing a control of vibrating the driving torque of the driving means ,
A control program for a biological operation assisting device, which is executed by a computer.

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