JP2020062151A - Walking assist device and controller - Google Patents

Abstract

To provide a walking assist device which can be used without a trouble even when lower limbs of a user are located under water, and a controller of the walking assist device.SOLUTION: A walking assist device 10 includes a fluid pressure actuator 201 attached to a thigh part of a user 20, and a fluid pressure actuator 202 attached to a leg part of the user 20, and a controller which controls the fluid pressure actuator 201 according to the pressure in the fluid pressure actuator 202. The fluid pressure actuator 201 and the fluid pressure actuator 202 include respective cylindrical tubes that expand and contract by the fluid pressure. The controller is arranged apart from the fluid pressure actuator 201 and the fluid pressure actuator 202.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a walking assist device and a controller.

  Electric parts such as an electric motor and a position detection sensor are widely used in a walking assist device that assists the walking of a user by using power (see Patent Document 1).

JP, 2017-46779, A

  However, since the above-described conventional walking assist device uses electric parts such as an electric motor and a position detection sensor, it is not suitable for walking assist in a state where the lower limb is located in water, such as walking training in water. There's a problem.

  Therefore, the present invention has been made in view of such a situation, and an object thereof is to provide a walking assist device that can be used without a problem even when a user's lower limb is located in water, and a controller of the walking assist device. To do.

  One aspect of the present invention is a walking assist device that assists walking of a user, including a first fluid pressure actuator provided on the thigh of the user and a second fluid pressure actuator provided on the lower thigh of the user. A fluid pressure actuator and a controller that controls the first fluid pressure actuator based on the pressure in the second fluid pressure actuator are provided, and the first fluid pressure actuator and the second fluid pressure actuator are the fluid pressure. The controller has a cylindrical tube that expands and contracts according to, and the controller is provided separately from the first fluid pressure actuator and the second fluid pressure actuator.

  According to the above-described walking assist device and controller, even when the lower limbs of the user are located in water, they can be used without any problem.

FIG. 1 is a diagram showing an example of walking training using the walking assist device 10. FIG. 2 is a schematic diagram of the walking assist device 10. FIG. 3 is a side view of the fluid pressure actuator 201. FIG. 4 is a functional block configuration diagram of the walking assist device 10. FIG. 5 is an operation flow chart of the walking assist device 10. FIG. 6 is an explanatory diagram of the walking state of the user 20. FIG. 7A is a diagram showing a change example of the air pressure (kPa) in the fluid pressure actuator 202. FIG. 7B is a diagram showing an example of a change in the air pressure differential value (kPa / s) in the fluid pressure actuator 202.

  Hereinafter, embodiments will be described with reference to the drawings. Note that the same functions and configurations are given the same or similar reference numerals, and description thereof will be omitted as appropriate.

(1) Overall Schematic Configuration of Walking Assist Device FIG. 1 shows an example of walking training using the walking assist device 10 according to the present embodiment. As shown in FIG. 1, the walking assist device 10 is attached to the lower leg of the user 20. The walking assist device 10 assists the walking of the user 20.

  In the example shown in FIG. 1, when the user 20 performs walking training using the treadmill 30 installed in the pool, the walking assist device 10 assists the walking motion of the user 20. The treadmill 30 is compatible with underwater use.

  That is, the user 20 executes the walking training in a state where a part (or all) of the lower limbs of the user 20 is located in the water. Walking training with the lower limbs located in the water is light on the knee joints, while water resistance can be used as a load, so a safe and high training effect can be expected.

  FIG. 2 is a schematic diagram of the walking assist device 10. Specifically, FIG. 2 shows the walking assist device 10 mounted on the lower leg of the user 20.

  As shown in FIG. 2, the walking assist device 10 includes a waist band 110, a knee band 120, and a shoe part 130. Although only one leg is shown in FIG. 2, the knee band 120 and the shoe 130 are attached to both legs.

  The waist band 110 is worn on the waist of the user 20. Specifically, the waist band 110 is wrapped around and fixed to the waist and abdomen of the user 20. The end of the waist band 110 is locked to the waist band 110 using a locking member such as a surface fastener.

  The knee band 120 is worn on the knee of the user 20. Specifically, the knee band 120 is wrapped around and fixed to the knee of the user 20. A hook-and-loop fastener or the like may be used for the knee band 120, or may be made of a material having elasticity while having a certain support force.

  The shoe 130 is attached to the foot of the user 20. Specifically, the shoe portion 130 is fixed to the foot portion of the user 20 by sliding the foot portion of the user 20 in. Since the shoe portion 130 is used in water, it is preferably made of rubber or a resin material.

  A fluid pressure actuator 201 is connected to the waist band 110 and the knee band 120. A fluid pressure actuator 202 is connected to the knee band 120 and the shoe 130. That is, two fluid pressure actuators are used for one leg.

  The fluid pressure actuator 201 is an actuator that uses the pressure of a fluid, and the length of the fluid pressure actuator 201 can be changed. The same applies to the fluid pressure actuator 202.

  In the present embodiment, air is used as the fluid, and the fluid pressure actuator 201 and the fluid pressure actuator 202 have a pressure tank 176 (not shown in FIGS. 1 and 2 through the control valve 161 and the control valve 162). 4) is connected.

  The fluid pressure actuator 201 is provided on the thigh of the user 20. In the present embodiment, the fluid pressure actuator 201 constitutes a first fluid pressure actuator.

  Specifically, the fluid pressure actuator 201 is attached to the front side of the thigh. The fluid pressure actuator 201 assists the walking of the user 20. Specifically, the fluid pressure actuator 201 assists the contracting operation of the muscle (quadriceps femoris muscle or the like) located on the front side of the thigh.

  The fluid pressure actuator 202 is provided on the lower leg of the user 20. In the present embodiment, the fluid pressure actuator 202 constitutes a second fluid pressure actuator.

  Specifically, the fluid pressure actuator 202 is provided from the calf of the user 20 to the ankle. The fluid pressure actuator 202 is used to detect the walking motion of the user 20. Further, in the present embodiment, the fluid pressure actuator 202 also assists the user 20 in walking.

  The fluid pressure actuator 201 and the fluid pressure actuator 202 are actuators that use fluid and do not have any electrical mechanism, and thus can be used in water without problems. Further, as will be described later, the actuator main body 210 (not shown in FIG. 2, see FIG. 3) is extremely lightweight (about 100 g) because it can be made of rubber and organic fibers.

  The fluid pressure actuator 201 and the fluid pressure actuator 202 are controlled by a controller 300 (not shown in FIG. 2, see FIG. 4).

(2) Configuration of Fluid Pressure Actuator FIG. 3 is a side view of the fluid pressure actuator 201 according to the present embodiment. As shown in FIG. 3, the fluid pressure actuator 201 includes an actuator body 210 and a connecting portion 220. In the present embodiment, the fluid pressure actuator 202 has the same configuration as the fluid pressure actuator 201.

  The actuator body 210 includes a tube 211 and a sleeve 212. A fluid flows into the actuator body 210 through the fitting 230 and the passage hole 240. Connection parts 220 are provided at both ends of the fluid pressure actuator 201.

The actuator body 210, by inflow of fluid into the tube 211, shrunk in the axial direction _{D AX} of the actuator body portion 210 expands in the radial direction _{D R.} Further, the actuator body portion 210, the outflow of the fluid from the tube 211, expanded in the axial direction _{D AX} of the actuator body portion 210, to shrink in the radial direction _{D R.}

  The fluid pressure actuator 201 exerts a function as an actuator by such a shape change of the actuator body 210. The fluid pressure actuator 201 is a so-called McKibben type.

  The fluid used to drive the fluid pressure actuator 201 may be a gas such as air or a liquid such as water or mineral oil, but considering that it is used in the walking assist device 10, a hydraulic pressure that exerts a large contracting force. There is no need to drive. Therefore, in the present embodiment, as described above, it is preferable to use air as the fluid used to drive the fluid pressure actuator 201. That is, the fluid flowing into the fluid pressure actuator 201 is air.

  The fitting 230 has a hose 181 (see FIG. 4) connected to a driving pressure source of the fluid pressure actuator 201, specifically, an air compressor 175 and a pressure tank 176 (not shown in FIG. 3, see FIG. 4). So that it protrudes.

  The fluid flowing in through the fitting 230 passes through the passage hole 240 and flows into the inside of the actuator body 210, specifically, the inside of the tube 211.

  The tube 211 is a cylindrical body that expands and contracts due to the pressure of fluid. The tube 211 is made of an elastic material such as butyl rubber because it repeatedly contracts and expands with a fluid. That is, the tube 211 is preferably made of a predetermined rubber material.

  When hydraulically driving the fluid pressure actuator 201, it should be at least one selected from the group consisting of NBR (nitrile rubber) having high oil resistance, hydrogenated NBR, chloroprene rubber, and epichlorohydrin rubber. Is preferred.

  The sleeve 212 has a cylindrical shape and covers the outer peripheral surface of the tube 211. The sleeve 212 is a restraint member made of fibers that restrains the expansion and deformation of the tube 211 by a predetermined amount or more.

  Specifically, the sleeve 212 is a stretchable structure in which cords oriented in a predetermined direction are knitted, and the rhombus shape is repeated by intersecting the oriented cords. By having such a shape, the sleeve 212 is pantograph-deformed, and follows the tube 211 while restricting the contraction and expansion of the tube 211.

  As the cord forming the sleeve 212, it is preferable to use a fiber cord of aromatic polyamide (aramid fiber) or polyethylene terephthalate (PET). However, the fiber cord is not limited to this kind of fiber cord, and may be a high-strength fiber such as PBO fiber (polyparaphenylenebenzobisoxazole) or a metal cord composed of an ultrafine filament.

  The details of the fluid pressure actuator 201 may be the same as, for example, the configuration described in International Publication No. 2017/010304.

(3) Functional Block Configuration of Walking Assist Device FIG. 4 is a functional block configuration diagram of the walking assist device 10. In FIG. 4, the control valve 161, the control valve 162, the pressure sensor 170, the air compressor 175, the pressure tank 176, the hose 181, the hose 182, the fluid pressure actuator 201, and the fluid pressure actuator 202, which are the components of the walking assist device 10, are shown. Also, the controller 300 is schematically shown.

  The control valve 161 and the control valve 162 are controlled by the controller 300. The control valve 161 and the control valve 162 are connected to the pressure tank 176.

  An air compressor 175 is connected to the pressure tank 176. The air compressor 175 supplies air to the pressure tank 176. The pressure tank 176 maintains the air sent by the air compressor 175 at a predetermined pressure.

  The air compressor 175 supplies air to the pressure tank 176 when the pressure inside the pressure tank 176 drops below a predetermined value due to the operation of the fluid pressure actuator 201 and the fluid pressure actuator 202.

  The control valve 161 is connected to the fitting 230 (see FIG. 3) of the fluid pressure actuator 201 via the hose 181. Compressed air is sent to the fluid pressure actuator 201 via the control valve 161.

  Similarly, the control valve 162 is connected to the fitting 230 (see FIG. 3) of the fluid pressure actuator 202 via the hose 182. Compressed air is sent to the fluid pressure actuator 202 via the control valve 162.

  The pressure sensor 170 is connected to the control valve 162 and detects the pressure in the fluid pressure actuator 202.

  The controller 300 controls the fluid pressure actuator 201 based on the pressure in the fluid pressure actuator 202. Accordingly, the walking assist device 10 assists the walking of the user 20. In the present embodiment, as will be described later, the controller 300 also controls the fluid pressure actuator 202 to assist the user 20 in walking.

  The controller 300 includes, as hardware elements, a processor, a memory, an input device, an external interface, and the like. The function provided by the controller 300 is realized by executing a computer program (software) using the hardware element. It should be noted that some or all of the functions provided by the controller 300 may be realized by a digital signal processor (DSP) or an Application Specific Integrated Circuit (ASIC).

  The controller 300 is provided separately from the fluid pressure actuator 201 and the fluid pressure actuator 202. Specifically, as shown in FIG. 4, the fluid pressure actuator 201 and the fluid pressure actuator 202 are located in water, but the control valve 161, the control valve 162, the pressure sensor 170, the air compressor 175, and the pressure tank 176. The controller 300 is provided on the ground.

  The controller 300 controls the inflow timing of the fluid into the fluid pressure actuator 201 and the outflow timing of the fluid from the fluid pressure actuator 201 based on the change in the pressure in the fluid pressure actuator 202.

  Specifically, the controller 300 controls the control valve 161 based on the change in the air pressure inside the fluid pressure actuator 202 measured by the pressure sensor 170, and controls the timing of inflow of air into the fluid pressure actuator 201. . Further, the controller 300 controls the control valve 161 to control the outflow timing of the air that has flowed into the fluid pressure actuator 201.

  More specifically, a constant air pressure is applied to the fluid pressure actuator 202. When the user 20 starts walking, the pressure inside the fluid pressure actuator 202 changes due to the change in the length of the fluid pressure actuator 202. The controller 300 detects the intention of the user 20 to walk using the change in the pressure.

  Further, the controller 300 determines the walking cycle of the user 20 (may be referred to as a walking cycle or a walking pitch) based on whether or not the value indicating the pressure (air pressure) in the fluid pressure actuator 202 is below a predetermined threshold value. To detect.

  The controller 300 detects the walking cycle based on whether or not the value indicating the air pressure is out of the predetermined threshold range. The predetermined threshold value is set to a value that causes a state in which the value indicating the air pressure falls below at least once for each walking cycle of the user 20. The controller 300 can detect the walking cycle based on whether the value indicating the air pressure is below a predetermined threshold value or above a predetermined threshold value.

  The controller 300 controls the inflow timing of air into the fluid pressure actuator 201 and the outflow timing of air from the fluid pressure actuator 201 based on the detected walking cycle. The specific detection operation of the walking cycle will be described later.

  Further, the value of the air pressure in the fluid pressure actuator 202 itself may be used to detect the walking cycle, or the differential value of the air pressure may be used. Alternatively, both may be used together.

  Further, the controller 300 also controls the inflow timing of the fluid into the fluid pressure actuator 202 and the outflow timing of the fluid from the fluid pressure actuator 202 based on the change in the pressure in the fluid pressure actuator 202. That is, the fluid pressure actuator 202 is used not only for detecting the walking cycle of the user 20, but also for assisting the walking of the user 20.

(4) Operation of Walking Assist Device Next, the operation of the walking assist device 10 will be described. Specifically, an operation example of walking assist by the walking assist device 10 will be described.

  FIG. 5 is an operation flow chart of the walking assist device 10. As shown in FIG. 5, the walking assist device 10 detects the pressure (pneumatic pressure) of an actuator provided on the calf of the user 20, specifically, a fluid pressure actuator 202 (see FIG. 2 and the like). Yes (S10).

  More specifically, the walking assist device 10 detects the air pressure detected by the pressure sensor 170 (see FIG. 4) connected to the fluid pressure actuator 202.

  The walking assist device 10 determines, based on the detected air pressure, whether or not the user 20 is in a walking state, specifically, the walking intention of the user 20 (S20).

  When it is determined that the user 20 is in a walking state, the walking assist device 10 is provided in the fluid pressure actuator 201 provided in the thigh and the calf shin in accordance with the walking cycle of the user 20. Pressure is applied to the active fluid pressure actuator 202 (S30).

  The operation of detecting the walking intention of the user 20 by the walking assist device 10 and the walking assist operation will be further described.

  FIG. 6 is an explanatory diagram of the walking state of the user 20. As shown in FIG. 6, the user 20 starts walking (2 in the figure) from a stationary state (1 in the figure). After that, when the leg of the user 20 (the right leg in FIG. 6) enters the forward swing period, the walking assist device 10 detects the intention of the user 20 to walk by the fluid pressure actuator 202 (in the figure). 3)).

  As described above, the fluid pressure actuator 202 is in a state in which a constant air pressure is applied. In the fluid pressure actuator 202, when the length of the fluid pressure actuator 202 is extended, the pressure inside the fluid pressure actuator 202 increases. Then, in the swing phase, the length of the fluid pressure actuator 202 is shortened and the pressure of the fluid pressure actuator 202 is reduced.

  Specifically, it is stretched during the standing phase of the user 20, and then, during the front swing phase, the user 20 quickly contracts with the kicking motion of the ground. When the fluid pressure actuator 202 contracts within a short time, the response of the control for maintaining a constant pressure cannot catch up, and the pressure inside the fluid pressure actuator 202 temporarily decreases.

  The walking assist device 10 detects the walking intention of the user 20 by utilizing the change in the pressure.

  When the right leg of the user 20 enters the swing phase, the walking assist device 10 sends air to the fluid pressure actuator 201 and the fluid pressure actuator 202 provided on the thigh of the user 20, and the walking assistance device 10 of the user 20 moves. Assists walking.

Specifically, the fluid pressure actuator 201 and the fluid pressure actuator 202 contract in the axial direction D _AX (see FIG. 3) when air is sent, and assist the walking motion of the right leg of the user 20 (in the figure). 4)). Specifically, the walking assist device 10 assists the exercise of the right leg along the direction of the thick line with an arrow shown in 4) in the figure.

  When the right leg of the user 20 enters the stance phase, the walking assist device 10 ends the walking of the user 20 (5 in the figure)).

  7A and 7B show examples of changes in pressure inside the fluid pressure actuator 202 mounted on the user 20. Specifically, FIG. 7A shows a change example of the air pressure (kPa) in the fluid pressure actuator 202. FIG. 7B shows a change example of the differential value (kPa / s) of the air pressure in the fluid pressure actuator 202. That is, FIG. 7B shows a value obtained by differentiating the air pressure shown in FIG. 7A.

  The walking assist device 10 may detect that the air pressure is below a predetermined threshold value by using the air pressure value itself shown in FIG. 7A, or the air pressure differential value shown in FIG. 7B may be a predetermined threshold value (in the figure). (See the dotted line in FIG. 3) may be detected.

  The walking assist device 10 detects the walking cycle T of the user 20, based on whether or not the value indicating the air pressure (air pressure or air pressure differential value) deviates from a predetermined threshold range. Specifically, the walking assist device 10 detects, for each leg of the user 20, a walking cycle T including a stance period, a front swing period, and a swing period.

  When the user 20 continues to walk, the walking assist device 10 controls the timing of walking assist by the fluid pressure actuator 201 and the fluid pressure actuator 202 based on the walking cycle T.

(5) Operation / Effect According to the above-described embodiment, the following operation / effect can be obtained. Specifically, the fluid pressure actuator 201 and the fluid pressure actuator 202 are actuators that use fluid (air), and are configured by the tube 211, the sleeve 212, and the like, and do not use electric parts such as an electric motor. Further, the controller 300 is provided separately from the fluid pressure actuator 201 and the fluid pressure actuator 202. That is, the fluid pressure actuator 201 and the fluid pressure actuator 202 are arranged in water such as a pool, but the controller 300 can be provided on land.

  Therefore, the walking assist device 10 can be used without problems even when the lower limb of the user 20 is located underwater, such as walking training underwater.

  When electric parts such as an electric motor and a position detection sensor are used like a conventional walking assist device, if the electric parts are to be used for walking training underwater, the electric parts must be waterproofed, and And increase in cost.

  The fluid pressure actuator 201 and the fluid pressure actuator 202 have a very simple structure, do not require waterproofing, and are lightweight (about 100 g). Also, the controller 300 and the like can be provided separately from the fluid pressure actuator 201 and the fluid pressure actuator 202. That is, the fluid pressure actuator 201 and the fluid pressure actuator 202 are extremely suitable for walking assistance, particularly walking assistance in water.

  In the present embodiment, the controller 300 moves into the fluid pressure actuator 201 (and the fluid pressure actuator 202) provided in the thigh based on the change in the pressure in the fluid pressure actuator 202 provided in the calf. The inflow timing of the fluid (and the outflow timing of the fluid) can be controlled. Therefore, the walking of the user 20 can be assisted at an appropriate timing according to the walking timing of the user 20.

  In the present embodiment, the walking cycle of the user 20 is detected based on whether the value indicating the pressure (air pressure) in the fluid pressure actuator 202 is below a predetermined threshold value, and the fluid is detected based on the detected walking cycle. The timing of inflow of air into the pressure actuator 201 is controlled. Therefore, the walking of the user 20 can be assisted at an appropriate timing according to the walking cycle of the user 20, that is, the walking speed.

  In this embodiment, the fluid flowing into the fluid pressure actuator 201 (and the fluid pressure actuator 202) is air. Since the fluid pressure actuator 201 (and the fluid pressure actuator 202) behaves like a spring by using air, it is possible to avoid a sudden force being applied to the body of the user 20. Thereby, safer walking assist can be realized.

(6) Other Embodiments The contents of the present invention have been described above with reference to the examples, but the present invention is not limited to these descriptions, and various modifications and improvements are possible. It is obvious to the trader.

  For example, in the above-described embodiment, the fluid pressure actuator 201 and the fluid pressure actuator 202 each include the tube 211 and the sleeve 212 that covers the outer peripheral surface of the tube 211, but the sleeve 212 does not necessarily cover the outer peripheral surface of the tube 211. You don't have to cover it. For example, the sleeve may be sandwiched between tubes, or the tube and the sleeve may be integrally formed.

  Further, although the fluid pressure actuator 202 is used not only for detecting the walking state of the user 20 but also for walking assist, it may be used only for detecting the walking state of the user 20. Further, in such a case, the fluid pressure actuator 202 may not include the sleeve 212.

  In the above-described embodiment, the walking training in water in which the lower limb of the user 20 is located in water has been described as an example, but the fluid pressure actuator 201 and the fluid pressure actuator 202 may not necessarily be used in water. That is, the walking assist device 10 may assist the walking of the user 20 on land.

  In the above-described embodiment, the user 20 is assumed to be a human, but the user is not necessarily limited to a human and may include an animal that requires walking assistance.

  Although the embodiments of the present invention have been described above, it should not be understood that the descriptions and drawings forming a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

10 Walking Assist Device 20 User 30 Treadmill 110 Lumbar Band 120 Knee Band 130 Shoe Part 161,162 Control Valve 170 Pressure Sensor 175 Air Compressor 176 Pressure Tank 181,182 Hose 201,202 Fluid Pressure Actuator 210 Actuator Body 211 Tube 212 Sleeve 220 Connecting part 230 Fitting 240 Through hole 300 Controller

Claims (7)

A walking assist device for assisting a user in walking,
A first fluid pressure actuator provided on the thigh of the user,
A second fluid pressure actuator provided on the lower leg of the user,
A controller for controlling the first fluid pressure actuator based on the pressure in the second fluid pressure actuator,
The first fluid pressure actuator and the second fluid pressure actuator each include a cylindrical tube that expands and contracts according to the pressure of a fluid,
The walking assist device, wherein the controller is provided separately from the first fluid pressure actuator and the second fluid pressure actuator.   The walking assist device according to claim 1, wherein the first fluid pressure actuator is a stretchable structure in which cords oriented in a predetermined direction are woven, and has a sleeve that covers an outer peripheral surface of the tube.   The walking assist device according to claim 1, wherein the controller controls a timing of inflow of a fluid into the first fluid pressure actuator based on a change in pressure in the second fluid pressure actuator.   The walking assist according to any one of claims 1 to 3, wherein the controller controls a timing of inflow of a fluid into the second fluid pressure actuator based on a change in pressure in the second fluid pressure actuator. apparatus.   The controller detects a walking cycle of the user based on whether or not a value indicating the pressure in the second fluid pressure actuator is out of a predetermined threshold range, and determines the inflow timing based on the walking cycle. The walking assist device according to claim 3, which is controlled.   The walking assist device according to any one of claims 1 to 5, wherein the fluid flowing into the first fluid pressure actuator is air. A controller used in a walking assist device that assists a user in walking,
The walking assist device,
A first fluid pressure actuator attached to the thigh of the user;
A second fluid pressure actuator attached to the lower leg of the user,
The first fluid pressure actuator has a cylindrical tube that expands and contracts according to the pressure of fluid,
The second fluid pressure actuator includes at least the tube,
The controller controls the first fluid pressure actuator based on the pressure in the second fluid pressure actuator, and is provided separately from the first fluid pressure actuator and the second fluid pressure actuator.

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