JP6717766B2 - Long leg brace with actuator - Google Patents

Description

The present invention relates to a long leg orthosis with an actuator.

As a device for walking assistance or rehabilitation for people with leg disabilities or people with paralysis due to stroke, etc., long leg orthoses supporting knee joints are used, and electric motors etc. that assist leg movements. There is also proposed an actuator-equipped long leg brace provided with an actuator unit including the driving body (see Patent Documents 1 to 3 below).

More specifically, a conventional long leg orthosis with an actuator is attached to a thigh side orthosis attached to a user's thigh, and is attached to the user's lower leg and connected to the thigh side orthosis so as to be rotatable around the user's knee joint. Lower leg orthosis, actuator mounted on the lower leg orthosis and capable of applying auxiliary force around the knee joint to the lower leg orthosis, and lower leg angle sensor for detecting a rotation angle of the lower leg around the knee joint with respect to the thigh. And a control device that controls the operation of the actuator, and the control device is configured to execute the operation control of the actuator based on a detection signal from the lower leg angle sensor.

That is, the conventional long leg orthosis with an actuator detects the movement of the lower leg (the angle around the knee joint of the lower leg with respect to the thigh), which is a control target portion to which assist force is applied by the actuator, by the lower leg angle sensor, The operation control of the actuator is performed so that an assisting force having a magnitude and a direction calculated based on the movement of the actuator is applied to the lower leg.

However, when the patient has paralysis due to a stroke or the like, the walking motion of the thigh (back and forth swing motion of the thigh around the hip joint) can be performed normally, but the walking motion of the lower leg (back and forth motion of the lower leg around the knee joint). In many cases, it cannot be performed normally.

In such a case, in the conventional long leg orthosis with an actuator, the operation control of the actuator is performed based on the movement of the lower leg that cannot perform a normal walking motion, and it is impossible to provide an accurate walking assist force. There was a fear.

It should be noted that an application unit that applies the assisting force, a control unit that controls the operation of the application unit, a detection unit that detects at least one of the hip joint angle and the hip joint angular velocity, and the phase of the thigh based on the detection result of the detection unit. There is proposed a walking assist device including a calculation unit that calculates an angle, and the control unit is configured to control the operation of the application unit based on the phase angle (see Patent Document 4 below).

However, the walking assist device described in Patent Document 4 also detects the movement of the control target site to which the assist force is to be applied, and applies the assist force to the thigh which is the control target site based on the detection result. This is for controlling the operation of the parts, and is based on the same technical idea as the long leg orthoses with actuators described in Patent Documents 1 to 3 above.

Japanese Patent No. 5724312 Japanese Patent No. 5799608 Patent No. 5386253 JP, 2016-002408, A

The present invention has been made in view of the above-described conventional technique, and is a long leg orthosis including an actuator capable of imparting a walking assist force around the knee joint to the lower leg, which allows the lower leg to normally walk. It is an object of the present invention to provide a leg-equipped orthosis with an actuator capable of giving an appropriate walking assist force to the lower leg according to the walking state during a walking cycle even for a user who has difficulty in walking.

In order to achieve the above-mentioned object, the present invention has a thigh-side brace attached to a user's thigh, a thigh-side brace attached to the user's lower leg, and rotatably connected to the thigh-side brace around the user's knee joint Lower leg orthosis, actuator attached to the lower leg orthosis and capable of applying an assisting force around the knee joint to the lower leg orthosis, and thigh posture detection capable of detecting an angle-related signal related to the hip joint angle of the user Means and a controller for controlling the operation of the actuator, wherein the thigh posture detecting means has a three-axis angular velocity sensor for detecting the angular velocity of the thigh and a three-axis acceleration sensor for detecting the acceleration of the thigh, and the control The apparatus calculates the angular velocity data from the triaxial angular velocity sensor at one sampling point based on the angular velocity data obtained by performing drift removal using the angular velocity data input from the triaxial angular velocity sensor at rest. The high frequency component of one Euler angle and the low frequency component of the second Euler angle calculated based on the acceleration data from the three-axis acceleration sensor at the one sampling point are summed up to add up the Euler angle at the one sampling point. Is calculated, and the thigh phase angle at the one sampling point is calculated based on the hip joint angle calculated from the combined Euler angle and the hip joint angular velocity calculated from the hip joint angle, and the thigh phase angle is calculated from the three axes. The heel contact time point detected based on the acceleration data from the acceleration sensor is converted into a heel contact phase angle with the control reference timing, and the thigh phase angle and the lower leg orthosis stored in advance in the control device are given. The heel contact at the one sampling point is applied to the assist force control data indicating the relationship with the assist force to calculate the assist force to be applied to the lower leg brace at the one sampling point, and the assist force is calculated. An actuator-equipped long leg brace configured to perform actuation control of the actuator so that the output is output.

Preferably, the control device, at the time of heel contact detecting Ru is configured to perform a drift removed by adding the correction Euler angle calculated from the 3-axis angular velocity sensor to the summing Euler angles during the heel contact detection.

Preferably, the control device is configured to plot a hip joint angle and a hip joint angular velocity used when calculating the thigh phase angle to create a trajectory diagram representing a periodic motion of the thigh for each walking cycle.

Preferably, the control device is configured to prohibit the operation of the actuator when a vector length defined by the hip joint angle and the hip joint angular velocity used when calculating the thigh phase angle is smaller than a predetermined threshold value. ..

According to the long leg orthosis with an actuator according to the present invention, the control device uses the angular velocity data input from the triaxial angular velocity sensor at rest for the angular velocity data from the triaxial angular velocity sensor at one sampling point. High frequency component of the first Euler angle calculated based on the angular velocity data that has been subjected to drift removal and a low frequency component of the second Euler angle calculated based on the acceleration data from the triaxial acceleration sensor at the one sampling point. And the summed Euler angle at the one sampling point is calculated, and the thigh at the one sampling point is calculated based on the hip joint angle calculated from the summed Euler angle and the hip joint angular velocity calculated from the hip joint angle. A phase angle is calculated, the thigh phase angle is converted into a heel contact phase angle with a heel contact time point detected based on acceleration data from the triaxial acceleration sensor as a control reference timing, and stored in advance in the control device. The heel contact phase angle at the one sampling point is applied to the assist force control data indicating the relationship between the thigh phase angle and the assist force to be applied to the lower leg brace, and the lower leg side at the sampling point. Since it is configured to calculate the assisting force to be applied to the brace and execute the actuator actuation control so that the assisting force is output, for a user who has difficulty walking the lower leg normally. Also, it is possible to apply an appropriate walking assist force to the lower leg according to the walking state during the walking cycle.

Further, according to the long leg brace with an actuator according to the present invention, since the heel contact is used as the walking cycle reference timing, it is possible to accurately grasp the timing when the walking assist force is required during the walking cycle.

FIG. 1 is a perspective view of a long leg orthosis with an actuator according to an embodiment of the present invention. FIG. 2 is a partial front view of the long leg orthosis. FIG. 3 is a partially exploded perspective view of the long leg orthosis, showing a state viewed from the outside in the user width direction. FIG. 4 is a partially exploded perspective view of the long leg orthosis, showing a state seen from the inside in the user width direction. FIG. 5 is an exploded perspective view of a thigh frame and a lower leg frame in the long leg orthosis. FIG. 6 is a partial vertical cross-sectional view of an actuator unit in the long leg orthosis. FIG. 7 is an end view taken along the line VII-VII in FIG. FIG. 8 is a block diagram of hip joint angle calculation in the long leg orthosis. FIG. 9 is a trajectory diagram obtained by plotting the hip joint angle θ and the hip joint angular velocity ω calculated by the control device of the long leg orthosis over one walking cycle. FIG. 10 is a graph in which the thigh phase angle φ calculated by the control device is plotted for each walking cycle. FIG. 11 is a schematic diagram showing the transition of the walking state during one walking cycle. FIG. 12 is a graph showing an example of auxiliary force control data stored in the control device in advance, which shows a relationship between a walking state during one walking cycle and an auxiliary force to be output by the actuator unit. FIG. 13 is a flowchart of the actuator operation control mode executed by the control device.

Hereinafter, one embodiment of a long leg orthosis with an actuator according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 and FIG. 2 show a perspective view and a partial front view of the long leg orthosis 1 according to the present embodiment, respectively.
Further, FIGS. 3 and 4 are partially exploded perspective views of the user 1 of the long leg orthosis viewed from the outer side and the inner side in the width direction, respectively.

The long leg orthosis 1 is a device to be worn by a user who has hemiplegia due to a person with a leg disability or a stroke or the like to assist walking, or for rehabilitation. It is configured so that a walking assist force can be applied to the lower leg.

Specifically, as shown in FIGS. 1 to 4, the long lower limb brace 1 includes a thigh-side brace 10 mounted on the user's thigh, a crus side brace 30 mounted on the user's lower leg, and the thigh-side brace. The actuator unit 100 is attached to the lower leg brace 30 and can apply an assisting force around the knee joint to the lower leg orthosis 30.

In the present embodiment, the thigh-side brace 10 has a thigh mounting body 15 to be mounted on the user's thigh, and a thigh frame 20 connected to the thigh mounting body 15.

The thigh attachment body 15 can take various forms as long as it can be attached to the user's thigh.
In the present embodiment, as shown in FIG. 1, the thigh mounting body 15 has a tubular shape having a mounting hole into which a user's thigh can be inserted and which fits the thigh.

As shown in FIGS. 1 to 4, the thigh frame 20 has a first thigh frame 20(1) extending vertically along the user's thigh on the outer side in the width direction of the user.

In the present embodiment, as shown in FIGS. 1 to 4, the thigh frame 20 further includes the first thigh frame 20(1) sandwiching the user's thigh inserted into the thigh attachment body 10. The second thigh frame 20(2) extends vertically along the user's thigh on the inner side in the width direction of the user so as to face each other.

In the present embodiment, the lower leg orthosis 30 has a lower leg mounting body 35 mounted on the lower leg of the user, and a lower leg frame 40 connected to the lower leg mounting body 35.

The lower leg mount 35 may have various shapes as long as it can be mounted on the lower leg of the user.
In the present embodiment, as shown in FIG. 1, the lower leg mounting body 35 has a tubular shape having a mounting hole into which the lower leg of the user can be inserted and which fits the lower leg.

As shown in FIGS. 1 to 4, the lower leg frame 40 includes a first lower leg frame 40(1) extending vertically along the lower leg of the user on the outer side in the width direction of the user.

In the present embodiment, as shown in FIGS. 1 to 4, the lower leg frame 40 further includes the first lower leg frame 40(1) sandwiching the user's lower leg inserted into the lower leg mounting body 30. The second lower leg frame 40(2) extends vertically along the lower leg of the user on the inner side in the width direction of the user so as to face each other.

In the present embodiment, the crus orthosis 30 further includes a foot mount 65 on which a user places a foot, and a foot frame 60 that supports the foot mount 65 and is connected to the crus frame 40. have.

The lower leg side brace 30 is connected to the thigh side brace 10 so as to be rotatable around the knee joint of the user.
That is, the lower leg frame 40 is rotatably connected to the upper leg frame 20 about the swing axis X of the knee joint of the user.

As described above, in the present embodiment, the thigh frame 20 has the first and second thigh frames 20(1) and 20(2), and the lower leg frame 40 is the first and second lower leg frames 40. (1) and 40(2).

Therefore, the first lower leg frame 40(1) is rotatably connected to the first thigh frame 20(1) about the swing axis X, and the second lower leg frame 40(2) is connected to the second thigh frame 20. It is connected to (2) so as to be rotatable around the swing axis line X.

FIG. 5 shows an exploded perspective view of the thigh frame 20 and the lower leg frame 40.
As shown in FIG. 5, the thigh frame 20 is fixed to the thigh frame body 21 extending in the vertical direction and the thigh frame body 21 by pin connection or welding so as to sandwich the lower end portion of the thigh frame body 21. It has a pair of connecting pieces 22a and 22b.

The pair of connecting pieces 22a and 22b are an outer connecting piece 22a located on the side of the thigh frame main body 21 away from the user's leg and an inner connecting piece on the side of the thigh frame main body 21 close to the user's leg. It has a piece 22b.

The lower leg frame 40 is connected to the pair of connecting pieces 22a and 22b so as to be rotatable around the swing axis X while being inserted between the pair of connecting pieces 22a and 22b.

More specifically, mounting holes 23 and 43 are formed in the upper portion of the pair of connecting pieces 22a and 22b and the lower leg frame 40 coaxially with the swing axis line X along the user width direction.

The first thigh frame 20(1) and the first lower leg frame 40(1) located on the side where the actuator unit 100 is mounted (outer side of the user's corresponding leg in the user width direction) are the first It is rotatably connected about the swing axis line X via a rotation connecting tool 50(1).

The first rotary connector 50(1) includes a first female screw member 51(1) and a first male screw member 55(1) that are separably connected to each other in the mounting holes 23, 43. Have

The first female screw member 51(1) includes a tubular portion 52 inserted into the attachment hole 23 from the side of the inner connecting piece 22b, and the tubular portion 52 at a position closer to the user's leg than the attachment hole 23. And a flange portion 53 that extends radially outward from the cylindrical portion 52, and a threaded hole that opens to the free end side is formed in the cylindrical portion 52.

The first male screw member 55(1) includes a tubular portion 56 inserted into the attachment hole 23 from the side of the outer connecting piece 22a, and the tubular portion at a position separated from the user's leg by the attachment hole 23. 56 and an engaging convex portion 57 extending from 56.

A male screw to be screwed into the screw hole of the first female screw member 51(1) in the mounting holes 23, 43 is formed in the tubular portion 56 of the first male screw member 55(1). There is.

The male screw formed on the first male screw member 55(1) and the female screw of the first female screw member 51(1) are screwed into the mounting holes 23, 43, whereby the first lower leg A frame 40(1) is swingably connected to the first thigh frame 20(1).

The second thigh frame 20(2) and the second lower leg frame 40(2), which are located on the inner side in the user width direction with respect to the leg corresponding to the user, are connected via the second rotation connector 50(2). They are connected so as to be rotatable around the swing axis line X.

The second turning connector 50(2) includes a second female screw member 51(2) and a second male screw member 55(2) that are detachably connected to each other in the mounting holes 23, 43. Have

The second female screw member 51(2) has the same structure as the first female screw member 51(1).

The second male screw member 55(2) includes a tubular portion 56 that is inserted into the attachment hole 23 from the outer connecting piece 22a side, and the tubular portion 56 on the inner side in the user width direction from the attachment hole 23. And a flange portion 58 that extends radially outward from.

The cylindrical portion 56 of the second male screw member 55(2) is formed with a male screw to be screwed into the screw hole of the second female screw member 51(2) in the mounting holes 23, 43. There is.

The male screw formed on the second male screw member 55(2) and the female screw of the second female screw member 51(2) are screwed into the mounting holes 23, 43, whereby the second lower leg The frame 40(2) is swingably connected to the second thigh frame 20(2).

Reference numeral 53a in FIG. 5 is a radial outward projection provided on the flange portion 53, and the female screw member 51 is engaged with the concave portion formed on the inner connecting piece 22b so that the inner thread member 51 is connected to the inner connecting member 22b. The piece 22b (that is, the thigh frame 20) is held so as not to be relatively rotatable around the axis.

In the present embodiment, as shown in FIGS. 1 to 4, the long lower limb orthosis 1 further has a lock for prohibiting rotation of the lower leg frame 40 around the swing axis X with respect to the thigh frame 20. It has a member 70.

The locking member 70 surrounds the thigh frame 20 and the lower leg frame 40 to connect the two frames 20, 40, and the lower leg frame 40 rotates relative to the thigh frame 20 about the swing axis X. The locked state for preventing such a situation (the state shown in FIGS. 1 to 4) and the connection between the thigh frame 20 and the lower leg frame 40 are released, and the lower leg frame 40 swings with respect to the thigh frame 20. It is configured to be in a released state that allows relative rotation around the axis X.

In addition, in the present embodiment, the lock member 70 acts on the first thigh frame 20(1) and the first lower leg frame 40(1) and is positioned on the outer side in the user width direction (first lock member 70(). 1) and a second lock member 70(2) located on the inner side in the user width direction that acts on the second thigh frame 20(2) and the second lower leg frame 40(2).

Further, in the present embodiment, as shown in FIG. 5, the upper end surface 45 of the lower leg frame 40 (the end surface facing the thigh frame 20) rotates from one side around the swing axis X to the other side. The lower surface 25 of the thigh frame 20 (the end surface facing the lower leg frame 40) corresponds to the upper end surface 45 of the lower leg frame 40, which is an inclined surface that increases the radial distance from the swing axis X. It is considered to be an inclined surface.

With such a configuration, the lower leg frame 40 is allowed to rotate only on one side around the swing axis X with respect to the thigh frame 20 (the direction in which the user's lower leg bends with respect to the thigh), and to the other side. Allows the lower leg to extend with respect to the thigh and prevents further rotation.

FIG. 6 shows a partial vertical sectional view of the actuator unit 100.
1 to 4 and 6, the actuator unit 100 includes an upper frame 120, a lower frame 340 rotatably connected to the upper frame 120 about a pivot axis Y, and the lower frame 340. A driving body 110 such as an electric motor for generating a driving force for rotating the shaft around the pivot axis Y, an upper coupling body 360 coupling the upper frame 340 to the thigh frame 20, and the pivot axis Y. The rotation center connecting body 180 and the lower connecting body 370 are arranged coaxially with the swing axis line X.

The upper frame 120 and the lower frame 340 are provided with an upper frame mounting hole 120a and a lower frame mounting hole 140a which are arranged coaxially with the pivot axis Y, respectively.

A rotation connecting shaft 151 is fixed to the lower frame mounting hole 140a, and the rotation connecting shaft 151 is supported by the upper frame mounting hole 120a via a bearing member 155 so as to be rotatable around its axis. As a result, the lower frame 340 is rotatably connected to the upper frame 120 about the pivot axis Y.

The driving body 110 includes a driving source 111 such as an electric motor, and a transmission mechanism 115 that transmits the driving force generated by the driving source 111 to the lower frame 340.

The driving source 111 is fixed to the outer surface of the upper frame 120.
In the present embodiment, as shown in FIG. 6, the drive source 111 is fixed to the outer surface of the upper frame 120 with the output shaft 111a extending downward.

In the present embodiment, as shown in FIG. 6, the transmission mechanism 115 includes a drive-side bevel gear 116 supported by the output shaft 111a so as to be relatively non-rotatable, and a lower frame 340 around the pivot axis Y. The driven bevel gear 117 meshes with the driving bevel gear 116 while being connected to the lower frame 340 so as to rotate integrally.

The actuator unit 100 may include a sensor (not shown) that detects a rotation angle of the rotation connecting shaft 151 about the axis, and the sensor may detect a rotation angle of the rotation connecting shaft 151 about the axis. Can be detected to recognize the swing angle of the lower frame 340 around the pivot axis Y.

As shown in FIGS. 3 and 4, the upper connecting body 360 is parallel to the pivot axis Y and is opened outward in the user width direction (toward the upper frame 120) so as to open the first thigh frame 20(1). ) And an engagement pin 362 provided on the upper frame 120 so as to be engaged with the engagement hole 361.

In the present embodiment, the upper coupling body 360 is provided with a lock mechanism.
As shown in FIG. 4, the lock mechanism is movable in the radial direction from the outer surface of the engagement pin 362, and is engaged in the radial direction outward from the outer surface of the engagement pin. And a convex portion 366 that can take a released position retracted in the engagement pin, a biasing member (not shown) that biases the convex portion 366 toward the engagement position, and the engagement pin 362. A concave portion (not shown) provided in the engaging hole so as to engage with the convex portion 366 in a state of being engaged with the engaging hole 361, and the biasing member in response to an external manual operation. And a release operation portion 367 for pushing the convex portion 366 to the release position against the biasing force of the.

As shown in FIGS. 4 and 6, the rotation center connecting body 180 is positioned coaxially with the swing axis X so that the first thigh frame 20(1) or the first lower leg frame 40(1). ), and an actuator-side rotation center connecting member 185 provided on the upper frame 120 or the lower frame 340 so as to be positioned coaxially with the pivot axis Y. Have

In the present embodiment, the engagement convex portion 27 of the first rotation connecting tool 50(1) acts as the equipment-side rotation center connecting member.

The actuator-side rotation center connecting member 185 has an actuator-side concave-convex engaging portion 185a that is detachably concave-convexly engaged with the equipment-side rotation center connecting member (the engaging convex portion 57 in the present embodiment). doing.

In the present embodiment, as shown in FIG. 6, the equipment-side rotation center connecting member (the engagement convex portion 57 in the present embodiment) is attachable to and detachable from the upper frame 120 and rotates about the axis. Engagement recesses that can be engaged are formed, and the engagement recesses act as the actuator-side uneven engagement portion 185a.

As shown in FIGS. 3, 4 and 6, the first lower leg frame 370 may include the first lower leg frame 370 in response to the lower frame 340 rotating around the pivot axis Y with respect to the upper frame 120. The lower frame 340 is connected to the first lower leg frame 40(1) so that the lower frame 40(1) rotates about the swing axis X with respect to the first thigh frame 20(1).

Specifically, as shown in FIG. 6, the lower frame 340 includes a base end portion 341 that is rotatably connected to the upper frame 120 via the rotation connecting shaft 151 and is rotatable about a pivot axis Y. It has a tip portion 345 extending from the end portion 341 toward the side closer to the first lower leg frame 40(1).

As shown in FIG. 6 and the like, in the present embodiment, the base end portion 341 supports the driven-side bevel gear 117 so as to integrally rotate about the pivot axis Y, whereby the drive member is driven. The driven bevel gear 117 and the base end 341 are integrally rotated around the pivot axis Y by the rotational power from 110.
In the present embodiment, the base end 341 has a flat plate shape extending substantially vertically.

As shown in FIGS. 4 and 6, the distal end portion 345 has a distal end surface 346 that forms a facing surface that faces the outer surface of the first lower leg frame 40(1) facing outward in the user width direction.
The front end surface 346 has a predetermined length in the width direction D corresponding to the width direction of the first lower leg frame 40(1) (that is, the front-back direction of the user).
In the present embodiment, the tip portion 345 has a flat plate shape extending substantially horizontally, and the tip surface 346 has a substantially rectangular shape.

As shown in FIGS. 4 and 6, the lower connecting body 370 includes a support hole 371 formed in the tip portion 345, an engagement pin 372 housed in the support hole 371 so as to be movable back and forth, and the engagement. It has an urging spring 373 for urging the pin 372, and an engagement arm 375 provided on the tip portion 345.

The support hole 371 opens in the opposing surface in the widthwise intermediate region of the opposing surface and extends in a direction substantially orthogonal to the outer surface of the first lower leg frame 40(1).

The engagement pin 372 may have a protruding position in which a tip is protruded from the facing surface and a retracted position in which the engaging pin 372 enters the support hole 371 so as to be separated from the first lower leg frame 40(1) from the protruding position. Further, it is accommodated in the support hole 371 so as to be movable in the axial direction.

The biasing spring 373 biases the engagement pin 371 toward the protruding position.
In the present embodiment, the biasing spring 373 is inserted between the base end portion of the engagement pin 371 and the bottom surface of the support hole 371.

Specifically, in the present embodiment, the support hole 371 is formed in the tip portion 345 so that one end side opens to the facing surface and the other end side opens to the back surface opposite to the facing surface, The other end of the support hole 371 is closed by a closing plate 348 fixed to the back surface of the tip portion 345. In this case, the closing plate 348 forms the bottom surface of the support hole 371.

The engagement arm 375 has an axially extending portion 376 extending along the pivot axis Y from the facing surface to the side closer to the first lower leg frame 40(1).
The axial extension portion 376 is arranged so that the first lower leg frame 40(1) can be arranged between the axial extension portion 376 and the engagement pin 372 in the width direction of the lower frame 340. A widthwise separation distance from the engagement pin 372 is set.

That is, the engagement pin 372 and the axial extension portion are arranged so that the first lower leg frame 40(1) can be located between the engagement pin 372 and the axial extension portion 376 in the user longitudinal direction. The distance in the width direction between 376 is set to be larger than the width of the first lower leg frame 40(1).

Here, the mounting operation of the lower frame 340 to the first lower leg frame 40(1) by the lower connecting body 370 will be described.
FIG. 7 shows an end view taken along the line VII-VII in FIG.

When connecting the lower frame 340 to the first lower leg frame 40(1) by the lower connecting body 370, first, the engaging pin 372 is moved to the retracted position against the urging force of the urging spring 373. While being positioned, the actuator unit 100 is pivoted with respect to the long lower limb orthosis body to a position where the first lower leg frame 40(1) overlaps with the axial extension portion 376 in the direction along the pivot axis Y. Move relative to Y direction.

At this time, preferably, the movement of the engagement pin 372 to the retracted position can be performed via the outer side surface of the first lower leg frame 40(1).
That is, the actuator unit 100 is moved so that the engagement pin 372 moves from the projecting position to the retracted position with the outer surface of the first lower leg frame 40(1) abutting the engagement pin 372. The first lower leg frame 40(1) can be relatively moved in the approach direction.
This state is shown by a broken line in FIG.

When the lower frame 340 is rotated in the connecting direction around the pivot axis Y (clockwise direction in FIG. 7) from the state shown by the broken line in FIG. 7, the engagement pin 372 and the first lower leg frame 40 The contact with (1) is released, and the engagement pin 372 is positioned from the retracted position to the projecting position by the urging force of the urging spring 373.

As a result, the first lower leg frame 40(1) is sandwiched by the engagement pin 372 and the axially extending portion 376 in the width direction of the lower frame 340 (the front-back direction of the user) (see FIG. 7). Solid line), the lower frame 340 is movable relative to the first lower leg frame 40 (1) in the longitudinal direction of the frame, and the rotation of the lower frame 340 around the pivot axis Y with respect to the upper frame 120. An interlocking state in which the first lower leg frame 40(1) is rotated around the swing axis X with respect to the thigh frame 20 in association with the rotation operation appears.

The lower frame 340, which is connected to the first lower leg frame 40(1) by the lower connecting body 370, can be removed by performing an operation reverse to that at the time of wearing.
That is, when the lower frame 340 is connected to the first lower leg frame 40(1) by the lower connecting body 370, the engagement pin 372 is located at the projecting position by the urging force of the urging spring 373. Has been done.

While pushing the engaging pin 372 at the projecting position to the retracted position against the biasing force of the biasing spring 373 by the artificial operation force, the lower frame 340 is released in the direction of releasing the pivot axis Y around the Y axis (in FIG. 7). Is rotated in the counterclockwise direction) so that the tip end portion of the engagement pin 372 comes into contact with the outer surface of the first lower leg frame 40(1) (the state of the broken line in FIG. 7).

Then, the lower frame 340 can be removed from the first lower leg frame 40(1) by relatively moving the first lower leg frame 40(1) and the lower frame 340 in a direction in which they are separated from each other. ..

Preferably, the engagement arm 375 extends from the axially extending portion 376 in a direction closer to the engagement pin 372 with respect to the width direction W of the facing surface, and the lower frame 340 causes the first lower leg frame 40 ( In the state of being connected to 1), the width direction extending portion 377 is opposed to the inner side surface (side surface facing inward in the user width direction) of the first lower leg frame 40(1).

The width direction extending portion 377 is configured such that the first lower leg frame 40(1) includes the engaging pin 372, the tip end surface 346 forming the facing surface, the axial direction extending portion 376, and the width direction extending portion. So that the axial separation distance from the distal end surface 346 is larger than the thickness of the first lower leg frame 40(1) so that the holding space 370S surrounded by 377 (see FIG. 4) can be arranged. Is composed of.

By providing the engagement arm 375 with the widthwise extending portion 377, the lower frame 340 is connected to the first lower leg frame 40(1) by the lower connecting body 370. Also, it is possible to effectively prevent relative movement of the first lower leg frame 40(1) in the direction of separation along the pivot axis Y direction, whereby the lower frame 340 unintentionally moves to the first direction. It is possible to effectively prevent detachment from the lower leg frame 40(1).

In the present embodiment, the engaging arm 375 has first and second engaging arms 375(1), 375(2) provided on one side and the other side in the width direction of the facing surface, respectively. Therefore, the lower frame 340 can be connected to the first lower leg frame 40(1) by rotating the lower frame 340 around the pivot axis Y in any direction from the state shown by the broken line in FIG. It is like this.

In addition, in the present embodiment, as shown in FIG. 7, the swing axis X is the center of the first lower leg frame 40(1) in the width direction (the front-back direction of the user) with respect to the first lower leg frame 40. It is deviated to one side in the width direction (user front-back direction) of (1). In FIG. 7, the swing axis line X is deviated rearward with respect to the front-back direction of the user with respect to the center of the first lower leg frame 40(1) in the width direction.

In such a case, the engagement pin 372 is arranged in the center of the lower frame 40 in the width direction (front-back direction of the user), and the engagement arm 375 sandwiches the engagement pin 372 to sandwich the lower frame. By having the first and second engagement arms 375(1), 375(2) located on one side and the other side of the width direction 40 (front side and rear side in the front-back direction of the user), The actuator unit 100 can be attached to either the left foot side or the right foot side of the long leg orthosis 1.

That is, when the actuator unit 100 is mounted on the left foot side of the long leg orthosis 1, the first lower leg frame 40(1) is moved by the engagement pin 372 and the first engagement arm 375(1). On the other hand, when the actuator unit 100 is mounted on the right foot side of the long leg orthosis 1 while sandwiched, the first lower leg frame 40(1) is formed by the engagement pin 372 and the second engagement arm 375(2). Can be sandwiched.

In addition, in the present embodiment, as shown in FIG. 7, the actuator unit 100 includes the engagement pin 372 and the first engagement arm 375(1) located forward in the front-back direction of the user. When the first lower leg frame 40(1) is mounted so as to sandwich the lower leg frame 40(1) and the rotation angle for rotating the first lower leg frame 40(1) with respect to the first thigh frame 20(1) is widened, Attach the actuator unit 100 so as to sandwich the first lower leg frame 40(1) by the engagement pin 372 and the second engagement arm 375(2) located rearward with respect to the front-rear direction of the user. You can

That is, when the first lower leg frame 40(1) is sandwiched by the engagement pin 372 and the first engagement arm 375(1) located forward in the front-back direction of the user, the initial posture of the lower frame 340 (the above-mentioned The posture of the lower frame 340 when the user takes the substantially upright posture with the actuator unit 100 mounted, and the posture shown by the solid line in FIG. 7) is the horizontal posture when viewed from the inside in the user width direction ( 7) (the posture indicated by the broken line in FIG. 7) is rotated clockwise about the pivot axis Y by a predetermined angle α.

Here, considering the movement of the left leg when the user wears the long leg brace 1 with the actuator unit 100 on the left leg and walks, the lower leg is bent with respect to the thigh. The first lower leg frame 40(1) rotates in the clockwise direction with respect to the first thigh frame 20(1) when viewed from the inside in the user width direction.

Therefore, in the initial posture in which the actuator unit 100 is mounted on the long leg orthosis 1, the lower frame 340 is in the horizontal posture (the posture shown by the broken line in FIG. 7) when viewed from the inside in the user width direction. Assuming that the user is rotating clockwise about the pivot axis Y by a predetermined angle α, the range in which the lower leg can be pushed in the bending direction with respect to the thigh to assist the user in bending the knee, that is, the lower frame. When the 340 is viewed from the inside in the user width direction, the rotation range in which the 340 can be rotated in the clockwise direction around the pivot axis Y is narrowed by the predetermined angle α with reference to the horizontal posture.

On the other hand, the actuator unit 100 is mounted so that the first lower leg frame 40(1) is sandwiched by the engagement pin 372 and the second engagement arm 375(2) located rearward with respect to the front-back direction of the user. Thus, the lower frame 340 is pivoted from the horizontal posture (the posture shown by the broken line in FIG. 7) when viewed from the inside in the width direction of the user in the initial posture (the posture in which the user is in a substantially upright state). It takes a posture rotated in the counterclockwise direction around Y by a predetermined angle α.

Therefore, in a range in which pushing force can be applied in the direction of bending the knee to assist the walking motion of the user, that is, when the lower frame 340 is viewed from the inside in the user width direction, the lower frame 340 is rotated clockwise around the pivot axis Y. It is possible to widen the possible rotation range by the predetermined angle α with reference to the horizontal posture.

Here, the control structure of the long leg orthosis 1 according to the present embodiment will be described.
The long leg orthosis 1 according to the present embodiment is configured to control the operation of the actuator unit 100 that applies a walking assist force to the lower leg based on the thigh posture of the user.
That is, the long lower limb orthosis 1 detects the movement of the thigh different from the lower leg which is the control target portion, and applies the walking assist force to the lower leg which is the control target portion based on the movement of the thigh. It is configured to control the operation of the.

Specifically, as shown in FIG. 1 and FIG. 3, the long lower limb orthosis 1 includes a thigh posture detecting means 510 capable of detecting an angle-related signal related to the thigh swing angle of the user, and the actuator unit 100. And a control device 500 that controls the operation.

The thigh posture detection means 510 is configured to detect the angle-related signals at a plurality of sampling points at predetermined timings during one walking cycle and transmit the signals to the control device 500.

The control device 500 includes a calculation unit including a control calculation unit that executes a calculation process based on a signal input from the thigh posture detection unit 510, an artificial operation member, or the like, a ROM that stores a control program, control data, or the like. A non-volatile storage means in which set values and the like are saved in a state where they are not lost even when the power is turned off, and the set values and the like are rewritable And a storage unit including the like.

The control device 500 calculates the thigh phase angle at the one sampling point based on the angle-related signal at the one sampling point, and the thigh phase angle and the lower leg stored in the control device 500 in advance. An assist to be applied to the lower leg orthosis 30 at the one sampling point by applying the thigh phase angle at the one sampling point to assist force control data indicating a relationship with the magnitude of the assist force to be applied to the side brace. The magnitude of the force is calculated, and the operation control of the actuator unit 100 is executed so that the auxiliary force of the magnitude is output.
That is, the control device 500 provides the thigh phase angle calculation means for calculating the thigh phase angle at the one sampling point based on the angle-related signal at the one sampling point, the thigh phase angle, and the lower leg brace. The assisting force to be applied to the lower leg orthosis 30 at the one sampling point by applying the thigh phase angle calculated by the thigh phase angle calculating means to assisting force control data indicating the magnitude of the assisting force to be applied. Acting as an assisting force calculating means for calculating the magnitude of the above, and an actuator operation controlling means for executing the operation control of the actuator unit 100 so that the assisting force of the magnitude calculated by the assisting force calculating means is output. Is configured.

As described above, by performing the operation control of the actuator unit 100 that applies the walking assist force to the lower leg based on the phase angle of the thigh, it is possible to accurately walk even for a user who has hemiplegia due to a stroke or the like. Auxiliary power can be supplied.

That is, the conventional walking assist device configured to apply the walking assist force by the actuator unit detects the movement of the control target portion to which the assist force is applied by the actuator unit, and based on the detection result, the actuator unit. It is configured to control the operation of the.

For example, in a conventional walking assistance device that supplies a walking assistance force to the thigh, it is supposed that the operation control of an actuator that applies the walking assistance force to the thigh is performed based on the detection result of the movement of the thigh. ..
Further, in a conventional walking assist device that supplies a walking assist force to the lower leg, it is supposed to control the operation of an actuator that applies the walking assist force to the lower leg based on the detection result of the movement of the lower leg. ..

However, in the case of a patient with hemiplegia due to stroke or the like, the walking motion of the thigh (back and forth swing motion around the hip joint) can be performed relatively normally, but the walking motion of the lower leg (back and forth swing motion around the knee joint). Often cannot be done normally.

When an attempt is made to give a walking assist force to the lower leg to such a patient, in the conventional walking assist device, the walking assist force is applied to the lower leg based on the movement of the lower leg that cannot perform a normal walking motion. Since the operation control of the provided actuator is performed, there is a possibility that an accurate walking assist force cannot be provided.

On the other hand, the long lower limb orthosis 1 according to the present embodiment is configured to perform the operation control of the actuator unit 100 that applies the walking assist force to the lower leg based on the thigh phase angle as described above. Has been done.
Therefore, even when the user has hemiplegia due to stroke or the like, it is possible to supply an appropriate walking assist force to the lower leg.

The thigh posture detecting means 510 may have various forms such as a gyro sensor, an acceleration sensor, and a rotary encoder as long as it can directly or indirectly detect the swing angle (hip joint angle) of the thigh.
For example, the thigh posture detecting means 510 may be configured to have only an acceleration sensor, and in this case, walking based on the acceleration (or position) and speed of the acceleration sensor without calculating the hip joint angle. The inside phase angle can be calculated.
In the long leg orthosis 1 according to the present embodiment, the thigh posture detecting means 510 includes a triaxial angular velocity sensor (gyro sensor) 511 (see FIG. 8 below) capable of detecting the angular velocity of the thigh. The control device 500 is configured to calculate the hip joint angle by integrating the thigh angular velocity detected by the triaxial angular velocity sensor 511.

As described above, by calculating the hip joint angle based on the angular velocities detected by the triaxial angular velocity sensor 511, the degree of freedom in designing the long leg orthosis 1 is increased as compared with the configuration in which the hip joint angle is detected by the rotary encoder. Can be improved.

That is, when the hip joint angle is detected by the rotary encoder, the relative movement angle between the body side detector fixed to the body and the thigh side detector fixed to the thigh so as to swing integrally with the thigh is calculated. Therefore, it is necessary to detect the solid-state detector and the thigh-side detector so that the solid-state detector and the thigh-side detector are not displaced from the body and the thigh, respectively.

On the other hand, according to the method of calculating the hip joint angle based on the angular velocity detected by the triaxial angular velocity sensor 511, the degree of freedom of design of the long leg orthosis 1 is improved without being restricted as described above. Can be made.

FIG. 8 shows a block diagram of a method for calculating the hip joint angle.
As shown in FIG. 8, in the long leg orthosis 1 according to the present embodiment, the thigh posture detecting means 510 has a triaxial acceleration sensor 515 in addition to the triaxial angular velocity sensor 511.

In this case, the control device 500 controls the high frequency component of the first Euler angle calculated based on the angular velocity data from the triaxial angular velocity sensor 511 and the second Euler angle calculated based on the acceleration data from the triaxial acceleration sensor 515. A low frequency component of the angle is summed to calculate a summed Euler angle, and a thigh phase angle is calculated based on a hip joint angle calculated from the summed Euler angle and a hip joint angular velocity calculated from the hip joint angle. To be done.

More specifically, as shown in FIG. 8, the control device 500 inputs angular velocity data based on the sensor coordinate axes from the triaxial angular velocity sensor 511 at predetermined sampling times, and uses the predetermined conversion formula for the angular velocity data. Are converted into angular velocity data (Euler angular velocity) indicating the correlation between the sensor coordinate axis and the global coordinate axis (space coordinate axis with the vertical direction as a reference).
Then, the control device 500 calculates the first Euler angle by integrating the angular velocity data (Euler angular velocity).

Preferably, the control device 500 uses the angular velocity data input from the triaxial angular velocity sensor 511 when stationary, and uses the angular velocity data based on the sensor coordinate axis input from the triaxial angular velocity sensor 511 at every predetermined sampling time. The drift can be removed.

Further, the control device 500 inputs the acceleration data based on the sensor axis from the three-axis acceleration sensor 515 at a predetermined sampling interval via the low-pass filter 520, and obtains the acceleration data and the gravitational acceleration that are input at rest. Based on the acceleration data input through the low-pass filter 520, the second Euler angle indicating the correlation between the sensor coordinate axis and the global coordinate axis (the spatial coordinate axis with the vertical direction as a reference) is calculated.

The control device 500 obtains the high frequency component of the first Euler angle obtained through the high pass filter 530 and the low frequency component of the second Euler angle obtained through the low pass filter 535. The hip joint angle θ is calculated from the combined Euler angle and the unit vector indicating the orientation of the thigh.

Preferably, the control device 500 detects the heel contact based on the acceleration data from the acceleration sensor 515, and at the time of detecting the heel contact, the correction Euler angle calculated from the angular velocity data from the triaxial angular velocity sensor 511 is added to the combined Euler. Drift can be removed by adding it to the corner.

The thigh phase angle φ is calculated by the following method.
When the control device 500 calculates the hip joint angle θn at the n-th sampling point Sn (n is an integer of 1 or more) from the walking cycle reference timing among the sampling points at predetermined intervals, the control device 500 differentiates the hip joint angle θn. The hip joint angular velocity ωn at the point Sn is calculated.

Then, the control device 500 calculates the thigh phase angle φn (=−Arctan(ωn/θn)) at the sampling point Sn based on the hip joint angle θn and the hip joint angular velocity ωn at the sampling point Sn.

FIG. 9 shows a trajectory diagram obtained by plotting a walking state defined by the hip joint angle θ and the hip joint angular velocity ω over one walking cycle.
As shown in FIG. 9, the thigh phase angle φ determined by the hip joint angle θ and the hip joint angular velocity ω is defined to change between 0 and 2π in one walking cycle.

Specifically, the hip joint angles when the thigh is positioned in front of and behind the user's body axis are “positive” and “negative”, respectively, and the hip joint angular velocity when the thigh is swung forward and backward. Are "positive" and "negative", respectively.

Under this condition, if the phase angle in the state where the hip joint angle is maximum in the “positive” direction and the hip joint angular velocity is “zero” (point P in FIG. 9) is 0, the walking area A1 (hip joint angle θ is The walking angle from the state where the hip joint angular velocity ω is “zero” to the maximum in the “positive” direction to the state where the hip joint angular velocity ω is “zero” and the hip joint angular velocity ω is the maximum in the “negative” direction) is the phase angle It corresponds to 0 to π/2.

In addition, the walking area A2 in FIG. 9 (where the hip joint angle θ is “zero” and the hip joint angular velocity is maximum in the direction of “negative”, the hip joint angle is maximum in the direction of “negative” and the hip joint angular velocity is “zero”). The walking area up to the state becomes equivalent to the phase angle π/2 to π.

Furthermore, the walking area A3 in FIG. 9 (when the hip joint angle θ is maximum in the direction of “negative” and the hip joint angular velocity ω is “zero”, the hip joint angle θ is “zero” and the hip joint angular velocity ω is “positive”). The walking area up to the maximum in the direction corresponds to the phase angle π to 3π/2.

Further, the walking area A4 (where the hip joint angle θ is “zero” and the hip joint angular velocity is maximum in the direction of “positive” from the maximum state in the direction of the hip joint angle “positive” and the hip joint angular velocity is “zero” in FIG. The walking area up to the state of (1) corresponds to a phase angle of 3π/2 to 2π.

The sampling interval of the thigh posture detecting means 510 is set so that a plurality of sampling points are included in one walking cycle, and the control device 500 calculates the thigh phase angle φ for each sampling point.

FIG. 10 shows a graph in which the thigh phase angle φ calculated by the control device 500 is plotted for each walking cycle.
In FIG. 10, the thigh phase angle φ in the four walking cycles from the first walking cycle C1 to the fourth walking cycle C4 is plotted.

Here, in the control device 500, assist force control data indicating the relationship between the thigh phase angle φ and the magnitude (including direction) of the walking assist force by the actuator unit 100 to be output to the lower leg is previously stored. Remembered
The assisting force control data is set for each user and for each user's rehabilitation degree through experiments or the like.

That is, when the control device 500 calculates the thigh phase angle φn at one sampling point Sn, the control device 500 applies the thigh phase angle φn to the assist force control data to determine the walking state defined by the thigh phase angle φn. At this time, the magnitude (including the direction) of the walking assist force to be output by the actuator unit 100 is acquired, and the operation control of the actuator unit 100 is performed so that the magnitude (including the direction) of the walking assist force is output. To execute.

As described above, the walking state in one walking cycle can be recognized based on the thigh phase angle φ. Therefore, by performing the operation control of the actuator unit 100 based on the thigh phase angle, the walking motion of the lower leg can be normally performed. It is possible to apply an appropriate walking assist force to the lower leg even for a user who is difficult to perform.

Here, the walking assist force required for walking will be described.
FIG. 11 shows a schematic diagram of a walking state that changes during one walking cycle.
As shown in FIG. 11, one gait cycle includes a heel contact period (a period before and after the stepped foot touches the floor) X1 including a heel contact point in which the heel is grounded in front of the user's body axis, and after the heel contact. Standing from the end of the stance phase X2, and the stance phase (the period in which the lower limb touching the floor moves rearward relative to the body) X2 in which the heel-contacted leg is moved relative to the rear side while being grounded. And the swing period X3 in which the legs are pulled up and relatively moved forward.

FIG. 12 shows an example of a change pattern of the assisting force defined by the assisting force control data.
In the example shown in FIG. 12, the assist force control data is the first torque pattern for preventing the knee bending by rotating the lower leg orthosis 30 in the knee extension direction around the knee joint in the heel contact period X1. Y1, a second torque pattern Y2 for rotating the lower leg brace 30 in the knee extension direction around the knee joint in the stance phase X2 to prevent knee bending, and stance from the end of the stance phase X2. In the initial stage X3a of the swing phase X2 in which the leg is pulled up and relatively moved forward, a third torque pattern for assisting the pulling up of the leg by rotating the lower leg orthosis 30 in the knee bending direction around the knee joint. Y3 and a fourth torque pattern Y4 for rotating the lower leg orthosis 30 in the knee extension direction around the knee joint in the latter stage X3b of the swing phase X3.

As described above, by performing the operation control of the actuator unit 100 using the assisting force control data indicating the relationship between the thigh phase angle φ and the walking assisting force, it is possible to perform appropriate walking assist according to the user. ..

Preferably, the control device 500 sets the thigh phase angle φn calculated at one sampling point Sn in the current walking cycle to the thigh phase angle at the corresponding sampling point Sn in the past walking cycle which has already been completed. The corrected phase angle φ(ave) is calculated by using the corrected phase angle φ(ave), and the corrected phase angle φ(ave) is applied to the auxiliary force control data to control the operation of the actuator unit 100.

According to such a configuration, even if the thigh phase angle φn(current) calculated at one sampling point Sn in the current walking cycle includes a large error for some reason, the same sampling point in the past walking cycle is included. Since the thigh phase angle φn(past) at Sn is used for correction (equalization), it is possible to smoothly supply the auxiliary force.

Specifically, the modified phase angle φ(ave) can be calculated by the following method.
The control device 500 calculates and stores the thigh phase angle φ at each of all sampling points included in one walking cycle.
Then, when the control device 500 detects the completion of one walking cycle, the controller 500 finds a predetermined phase pattern function representing a change pattern of the thigh phase angle φ with respect to the walking cycle based on the thigh phase angles φ at all sampling points by the least square method. Calculate using.

The phase pattern function is, for example,
φ(x)=a+bx+cx ² +dx ³ +ex ⁴ +fx ⁵
Can be
Then, the control device 500 is configured to calculate the coefficients a to f of the phase pattern function using the least squares method based on the thigh phase angles at all sampling points every time one walking cycle is completed. To be done.

Completion of one walking cycle can be determined by, for example, the control device 500 whether or not the walking state defined by the hip joint angle and the hip joint angular velocity has returned to the preset walking cycle reference timing.

In the example shown in FIG. 12, the heel contact is set as the walking cycle reference timing.
In this way, by using the heel contact as the walking cycle reference timing, it is possible to accurately grasp the timing during which the walking assist force is required during the walking cycle.

The timing of heel contact can be recognized by various methods.
For example, when the hip joint angular velocities when the thigh is swinging forward and backward with respect to the body axis of the user are positive and negative, respectively, the control device 500 calculates the calculated hip joint angular velocities. It can be configured to recognize as a heel contact time a time point when the phase angle advances from the positive value to zero (P in FIG. 9) by a predetermined phase angle Δα.

Instead of this, the long lower limb orthosis 1 is provided with heel contact detection means for detecting a heel contact, and the control device 500 recognizes the timing detected by the heel contact detection means as a heel contact time point, and at that timing, It is also possible to configure so that the thigh phase angle φ of is recognized as the heel contact phase angle.

When the acceleration sensor 515 is provided as in the long leg orthosis 1 according to the present embodiment, the acceleration sensor 515 can also be used as the heel contact detection means.
Alternatively, a pressure sensor capable of detecting the ground contact of the heel may be separately provided, and the pressure sensor may act as the heel contact detecting means.

When the completion of one walking cycle is detected in this way, the control device 500 calculates the phase pattern function based on the phase angle in the already completed walking cycle including the walking cycle that has been completed most recently.

Specifically, when the walking cycle C1 in FIG. 10 is completed, the control device 500, based on the thigh phase angle φ at all sampling points in the walking cycle C1,
φ(x)(C1)=a(1)+b(1)x+c(1)x ² +d(1)x ³ +e(1)x ⁴ +f(1)x ⁵
And φ(x)(C1) is stored as a phase pattern function of the thigh phase angle.

When the walking cycle C2 is completed, the control device 500, based on the thigh phase angle at the sampling point in the walking cycle C2 and the thigh phase angle at the sampling point in the walking cycle C1,
φ(x)(C2)=a(2)+b(2)x+c(2)x ² +d(2)x ³ +e(2)x ⁴ +f(2)x ⁵
Is calculated, and φ(x)(C2) is overwritten and saved as a phase pattern function of the thigh phase angle.

Specifically, in the second and subsequent walking cycles, the control device 500 stores the thigh phase angle φn(current) at the sampling point Sn in the current walking cycle (for example, the walking cycle C2) and at that time. The average value with the thigh phase angle φn(past) at the sampling point Sn in the past walking cycle calculated by the phase pattern function φ(x)(C1) ).

When the current walking cycle (for example, walking cycle C2) is completed, the control device 500 calculates the phase pattern function (for example, φ(x)(C2)) based on the corrected thigh phase angles at all sampling points. ,save.

In addition, as a mean value of the thigh phase angle φn(current) at the sampling point Sn in the current walking cycle and the thigh phase angle φn(past) at the corresponding sampling point Sn in the past walking cycle, the current walking cycle and the past walking are calculated. It is also possible to use the calculated value obtained by averaging the thigh phase angles in all walking cycles including the cycle under an equal condition, or weighting the thigh phase angles φn(current) of the current walking cycle and averaging them. It is possible to use the calculated value calculated, or it is also possible to use the calculated value obtained by weighting the thigh phase angle φn(past) in the past walking cycle and calculating the average.
Furthermore, it is also possible to correct the thigh phase angle of the current walking cycle using only the thigh phase angle at the sampling point in a predetermined walking cycle of the past walking cycles.

In the present embodiment, the corrected thigh phase angle is used as the thigh phase angle applied to the assist force control data.
For example, if the current walking cycle is the walking cycle C3 and the thigh phase angle at the sampling point Sn in the current walking cycle C3 is φn(C3), the control device 500 is stored at that time. Using the phase pattern function (φ(x)(C2) in this example), the thigh phase angle φn(C2) at the sampling point Sn in the past walking cycle is calculated, and the thigh phase angle φn(C3) and the thigh phase angle are calculated. The corrected thigh phase angle at the sampling point Sn is calculated based on φn(C2).

The control device 500 applies the corrected thigh phase angle calculated in this way to the assist force control data to determine the magnitude of the assist force to be output by the actuator unit 100 at the sampling point Sn in the current walking cycle C3. (And direction) is acquired, and the operation control of the actuator unit 100 is performed.

According to such a configuration, even if the thigh phase angle calculated at one sampling point in the current walking cycle (walking cycle C3 in the above example) contains a large error for some reason, the thigh phase angle is the same in the past walking cycle. Since the thigh phase angle at the sampling point is used for correction (equalization), it is possible to supply an appropriate assisting force by the actuator unit 100.

FIG. 13 shows a flow of the actuator operation control mode executed by the control device 500.

The control device 500 activates the actuator operation control mode in response to the activation signal input.
The activation signal is input, for example, in response to a manual operation by a user on a manual operation member such as a start button.

When the actuator operation control mode is activated, the control device 500 determines the hip joint angle θn at the one sampling point Sn based on the angle-related signal from the thigh posture detection means 510 at the one sampling point Sn. It is calculated (step S11), and the hip joint angular velocity ωn at the one sampling point Sn is calculated based on the hip joint angle θn (step S12).

The control device 500 calculates the thigh phase angle φn at the one sampling point Sn based on the hip joint angle θn and the hip joint angular velocity ωn (step S13).

Here, preferably, the control device 500 can determine whether or not the vector length of the vector Vn (see FIG. 9) defined by the hip joint angle θn and the hip joint angular velocity ωn exceeds a predetermined threshold value ( Step S14).

By including the step S14, it is possible to effectively prevent the actuator unit 100 from operating even though the walking motion is not started.
That is, a user who has hemiplegia or the like is likely to cause a posture change in a minute range against the intention before the start of a walking motion.
Such a slight posture variation is detected as a vector having a short vector length.

Therefore, the walking motion is determined by determining that the walking motion is performed only when the vector length of the vector Vn (see FIG. 9) defined by the hip joint angle θn and the hip joint angular velocity ωn exceeds the predetermined threshold. It is possible to effectively prevent the actuator unit 100 from accidentally operating even though the operation has not been started.

If NO in step S14, the control device 500 determines that the walking motion is not performed, and returns to step S11 without operating the actuator unit 100.

In the case of YES in step S14, the control device 500 calculates the thigh phase angle φn (curren) at the sampling point Sn in the current walking cycle calculated in step S13 in the previously completed walking cycle. Correction is performed using the thigh phase angle φn(past) at the corresponding sampling point Sn to calculate the corrected phase angle φn(ave) (step S15).
For example, when the control device 500 already calculates and stores the phase pattern function based on the walking data in the past walking cycle every time the walking cycle ends, the thigh phase at the sampling point Sn in the current walking cycle. The corrected phase angle φn(ave) at the sampling point Sn can be calculated based on the angle φn(curren) and the thigh phase angle at the sampling point Sn in the past walking cycle obtained based on the phase pattern function.

By including the step S15, even if the thigh phase angle calculated at one sampling point in the current walking cycle includes a large error for some reason, the thigh phase angle at the same sampling point in the past walking cycle is included. Since it is corrected (equalized) using, it is possible to supply an appropriate walking assist force according to the walking stage.

The control device 500 detects whether or not heel contact is performed (step S16), and if step S16 is YES (that is, heel contact is performed), the corrected phase angle calculated in step S15. Is stored as the heel contact phase angle corresponding to the heel contact (step S17), and the process proceeds to step S18.

In step S18, the control device 500 calculates the phase angle deviation between the corrected phase angle φ(ave) calculated in step S15 and the heel contact phase angle stored in step S17.
That is, in step 18, the control device 500 converts the corrected phase angle calculated in step S15 into a phase angle with the heel contact as the control reference timing.
In this way, by using the heel contact as the control reference timing, it is possible to more appropriately grasp the walking stage (walking state) during the walking cycle.

In addition, when the process proceeds to step 18 via step 17, the phase angle deviation becomes zero.
On the other hand, when step 17 is bypassed and step 18 is proceeded to, that is, when step 16 is NO, in step S18, the corrected phase angle calculated in step 15 and the heel contact phase stored at that time are stored. The deviation from the angle is the phase angle deviation.

The control device 500 applies a phase angle deviation to pre-stored “assist torque/phase angle” data to determine the magnitude and direction of the walking assist force to be output by the actuator unit 100 at the sampling point Sn. It is acquired (step S19), and the actuator unit is operated so that the walking assist force in the magnitude and direction is output (step S20).

The control device 500 determines whether or not one gait cycle has ended (step S21), and when it judges that one gait cycle has ended, the controller 500 uses the least squares method for the modified phase angle. The pattern function is calculated and stored (step S22).
If one walking cycle has not ended, step S22 is bypassed.

The control device 500 determines whether or not the end signal of the actuator operation control mode is input (step S23). If the end signal is not input, the process returns to step S11, and if the end signal is input. Ends the control mode.
The end signal is input, for example, in response to a user's manual operation on an artificial operation member such as an end button.

1 Long Lower Limb Orthosis 10 Thigh Orthosis 30 Lower Thigh Orthosis 100 Actuator Unit 500 Control Device 510 Thigh Posture Detecting Device 511 3-Axis Angular Velocity Sensor 515 3-Axis Acceleration Sensor

Claims (4)

A thigh-side brace attached to the user's thigh, a lower thigh-side brace attached to the user's lower leg and rotatably connected to the thigh-side brace around the user's knee joint, and attached to the thigh-side brace An actuator capable of applying an assisting force around the knee joint to the lower leg brace, and a thigh posture detecting means capable of detecting an angle-related signal related to a hip joint angle which is a front-back swing angle of a user's thigh; With a control device that controls the operation of the actuator,
The thigh posture detecting means has a three-axis angular velocity sensor for detecting the angular velocity of the thigh and a three-axis acceleration sensor for detecting the acceleration of the thigh,
The control device is calculated based on angular velocity data obtained by performing drift removal on the angular velocity data from the triaxial angular velocity sensor at one sampling point using the angular velocity data input from the triaxial angular velocity sensor at rest. The high frequency component of the first Euler angle and the low frequency component of the second Euler angle calculated based on the acceleration data from the triaxial acceleration sensor at the one sampling point, and summed at the one sampling point. calculates the Euler angles, the calculated femoral phase angle at said one sampling point based on the hip joint angular velocity is calculated as the hip joint angle calculated from the hip joint angle from summation Euler angles, the femoral phase angle, wherein The heel contact time point detected based on the acceleration data from the triaxial acceleration sensor is converted into a heel contact phase angle with the control reference timing, and the thigh phase angle and the crus side orthosis stored in advance in the control device. The heel contact phase angle at the one sampling point is applied to the assist force control data indicating the relationship with the assist force to be applied, and the assist force to be applied to the lower leg brace at the one sampling point is calculated. A long lower limb orthosis with an actuator, wherein the actuation control of the actuator is executed so that the assisting force is output. The control device removes drift by adding a corrected Euler angle calculated from the three-axis angular velocity sensor to a summed Euler angle at the time of detecting the heel contact when the heel contact is detected . Long leg brace with actuator. The control device according to claim 1 or, characterized in that to create a trajectory diagram representing the cyclic operation of the femoral hip joint angle and walking every cycle by plotting the hip joint angular velocity used for calculating the femoral phase angle The long leg orthosis with an actuator according to 2 . The control device according to claim 1 vector length bounded by the hip joint angle and the hip joint angular velocity used for calculating the femoral phase angle is smaller than a predetermined threshold value, characterized in that to prohibit the operation of the actuator 4. A long leg orthoses with an actuator according to any one of 3 to 3 .