JP2018083275A - Motion assist device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motion assist device capable of preventing collapse of an actuator in seating.SOLUTION: A motion assist device comprises: assist mechanisms 22B, 22D; a control device 29 for controlling motion of the assist mechanisms; and an input interface 27 for acquiring information of a seating operation of a user 100. The assist mechanisms comprise respectively: an assist wear body 21 comprising a waist restraining part 21a fixed to a waist 100a and a knee restraining part 21b fixed to a knee 100b and being worn by a user; and an actuator 1B, 1D provided on a position corresponding to a hip 100c, and connects both restraining parts. Each actuator has a first actuator structure 22B, 22D formed by spirally winding an elastic cylinder body 10. Based on information of the seating operation acquired by the input interface 27, a fluid is supplied to the first actuator when the user 100 is seated, for compressing the first actuator and inflating the first actuator in a radial direction, by control of the control device 29.SELECTED DRAWING: Figure 10B

Description

  The present invention relates to an operation assisting device using an actuator that expands and contracts in a longitudinal direction by controlling a fluid pressure in a hollow portion of a cylindrical body.

  In recent years, a walking support device that actively assists the movement of a user's leg by a link mechanism and an actuator has been studied. In such a walking support device, walking support is performed by mounting a link mechanism on the side of a leg and driving the link mechanism (see, for example, Patent Document 1).

  As a new attempt, assist pants using light and flexible fibrous actuators are being studied. When such an actuator is used, the actuator can be flexibly arranged along the body, so that a link mechanism is not required and a walking support device that can be worn under clothes can be realized.

  As one of the fibrous actuators, there has been known a McKibben actuator whose diameter has been reduced in recent years (see, for example, Patent Document 2). The McKibben actuator is composed of a rubber tube reinforced with a braided structure. The inside of the rubber tube is pressurized with a fluid, and the expansion in the radial direction is contracted in the axial direction while changing the braid angle like a pantograph. The actuator is expanded and contracted by converting to.

JP 2013-150714 A JP 59-197605 A

  When an assist suit is realized by a flexible fibrous actuator, it is desirable to arrange the actuator along a human muscle, unlike the case of using a link mechanism. Therefore, as an example of assist wear, in assist pants that support walking, an actuator should also be arranged on the buttocks. However, when the actuator is disposed on the buttocks, the actuator is sandwiched between the human body and the seat when sitting, and the actuator is crushed, which may cause damage or failure.

  In addition, the McKibben-type actuator expands and contracts in the axial direction by increasing or decreasing the internal fluid pressure. However, when the inside of the rubber tube is pressurized, free movement in the bending direction is inhibited. Therefore, it cannot move flexibly along the body like muscles.

  Therefore, the present invention provides an operation assist device that can prevent the actuator from being crushed when seated.

An operation assist device according to an aspect of the present invention includes:
An operation assist device for assisting a user's operation,
An assist mechanism;
A control device for controlling the operation of the assist mechanism;
An input interface for acquiring information on the user's sitting motion,
The assist mechanism is
An assist wear body having a waist restraint and a knee restraint, and a first actuator;
The assist wear body is attached to at least the lower half of the user,
The waist restraining portion is fixed to the user's waist,
The knee restraint is fixed to the user's knee,
The first actuator is disposed so as to connect between the waist restraining portion and the knee restraining portion, and is located at a portion of the assist wear main body corresponding to at least a position of the buttocks of the user. The actuator further has an elastic cylinder wound spirally,
At least one of the outer peripheral surface and the inner peripheral surface of the cylindrical body is provided with a spiral groove with the axial center of the cylindrical body as a central axis,
By controlling the pressure of the fluid in the hollow part of the cylindrical body, it expands and contracts in the radial direction and expands and contracts in the longitudinal direction.
The control device supplies the fluid to the first actuator based on the information on the seating motion acquired by the input interface, and controls the expansion of the first actuator in the radial direction.

  These comprehensive and specific aspects may be realized by a system, a method, and any combination of the system and the method.

  According to the operation assisting device according to the aspect of the present invention, the actuator disposed in the buttock is pressed during seating and expanded in the radial direction to prevent the actuator from being crushed, and damage and failure can be reduced.

FIG. 3 is a diagram schematically showing an actuator having the actuator structure of the motion assist device according to the first embodiment. FIG. 3 is a perspective view showing a part of a cylinder of the actuator structure of the motion assist device according to Embodiment 1. FIG. 3 is a cross-sectional view of a cylinder of the actuator structure of the motion assist device according to the first embodiment. It is the figure which made the cylindrical body of the structure for actuators of the operation assistance apparatus concerning Embodiment 1 straight shape, and was seen from the front. It is a longitudinal cross-sectional view of the cylinder shown in FIG. It is a flowchart which shows the drive method of the actuator of an operation assistance apparatus. It is sectional drawing which shows the bone | frame part of the 1st elastic member before pressurizing the fluid inside a cylinder. It is sectional drawing which shows a deformation | transformation of the bone part of the 1st elastic member after pressurizing the fluid inside a cylinder. It is a schematic diagram which shows the structure for actuators before pressurizing the fluid inside a cylinder. It is a schematic diagram which shows the expansion-contraction of the structure for actuators after pressurizing the fluid inside a cylinder. It is a schematic diagram which shows the structure for actuators before applying external force. It is a schematic diagram which shows the bending state of the structure for actuators after applying external force. It is a figure which shows when a user wears assist pants in an operation assistance apparatus, Comprising: It is the perspective view which looked at assist pants from the front side. It is a figure which shows when a user wears assist pants in an operation assistance apparatus, Comprising: It is the perspective view which looked at assist pants from the back side. It is a block diagram of control of an operation assistant device. It is explanatory drawing which shows the user's seating operation | movement in an operation | movement assistance apparatus. It is explanatory drawing which shows the acceleration detected by a motion sensor in each attitude | position of a user in a motion assistance apparatus. In the motion assist device, in each posture of the user, the trunk forward tilt angle (AFI) shown in the posture (c) of FIG. 12A and the myoelectric potentials of the outer vastus muscle and the front tibialis muscle detected by the myoelectric sensor. It is explanatory drawing which shows the change with. 4 is a flowchart illustrating a method of driving an actuator when seated in the motion assist device. FIG. 14B is an explanatory view similar to FIG. 12A, which is shown for comparison with FIG. 14B and FIG. 14C in the motion assist device. In an operation assist device, it is an explanatory view showing change with time of pressure applied to a structure for actuators and a structure for actuators. It is explanatory drawing which shows opening and closing of a valve | bulb in an operation assistance apparatus. FIG. 12B is an explanatory view similar to FIG. 12A, which is shown for comparison with FIG. 15B and FIG. 15C in the motion assist device. In an operation assist device, it is an explanatory view showing change with time of pressure applied to a structure for actuators and a structure for actuators. It is explanatory drawing which shows opening and closing of a valve | bulb in an operation assistance apparatus. 6 is a flowchart illustrating another method of driving the actuator when seated in the motion assist device. It is explanatory drawing which showed the operation | movement of a user's standing. It is explanatory drawing which shows the acceleration detected by a motion sensor in each attitude | position. FIG. 16B is an explanatory diagram showing changes in the trunk forward tilt angle (AFI) shown in the posture (g) of FIG. 16A and the myoelectric potential of the outer vastus muscle detected by the myoelectric sensor in each posture. It is a flowchart which shows the drive method of the actuator at the time of standing up. FIG. 16B is an explanatory view similar to FIG. 16A, which is shown for comparison with FIG. 18B and FIG. 18C in the operation assist device. It is explanatory drawing which shows the time change of the pressure applied to the structure 22A for actuators, and the structure 22B for actuators. It is explanatory drawing which shows opening and closing of a valve | bulb. In the posture (b) shown in FIG. 12A, when the actuator structure 22A contracts, it is an explanatory view showing a state in which a force is applied to the user in the direction in which the hip joint bends. In the posture (b) shown in FIG. 12A, when the actuator structure 22B contracts, it is an explanatory view showing a state in which a force is applied to the user in the direction in which the hip joint extends. It is the perspective view which looked at the assist pants of the operation assistance apparatus concerning Embodiment 2 from back. FIG. 10 is a block diagram of control of the operation assist device according to the second exemplary embodiment. When the actuator structure 22A on the left leg front side of the motion assist device according to the second embodiment is pressurized, the actuator structure 22A contracts and generates an assist force in the direction of bending the hip joint. It is. When the actuator structures 42A, 42B, 42C on the left rear side of the motion assist device according to the second embodiment are pressurized, the actuator structures 42A, 42B, 42C contract and assist in extending the hip joint. It is explanatory drawing which shows the state which generate | occur | produces force. 9 is a flowchart illustrating a method of driving an actuator when seated in the motion assist device according to the second embodiment. In the operation assistance apparatus concerning Embodiment 2, it is the same explanatory drawing as FIG. 12A shown for the comparison with FIG. 24B and FIG. 24C. It is explanatory drawing which shows the time change of the pressure applied with an actuator. It is explanatory drawing which shows opening and closing of valve | bulb 25, 45, 46. FIG. In the operation assist device, it is the same explanatory view as FIG. 12A, which is shown for comparison with FIG. 25B and FIG. 25C. It is explanatory drawing which shows the time change of the pressure applied with an actuator slightly different from FIG. 24B. It is explanatory drawing which shows opening and closing of valve | bulb 25, 45, 46 slightly different from FIG. 25C. It is a flowchart which shows the drive method of the actuator at the time of standing up. It is explanatory drawing which showed the operation | movement of standing up in an operation | movement assistance apparatus. It is explanatory drawing which shows the time change of the pressure applied with an actuator. It is explanatory drawing which shows opening and closing of valve | bulb 25, 45, 46. FIG. It is explanatory drawing which showed the operation | movement at the time of a fall. It is the perspective view which looked at the assist pants of the operation assistance apparatus concerning a modification from the back side. FIG. 30 is a flowchart showing a method for driving an actuator during seating in the modification of FIG. 29.

Embodiments according to the present invention will be described below in detail with reference to the drawings.
DESCRIPTION OF EMBODIMENTS Hereinafter, various embodiments of the present invention will be described before detailed description of embodiments of the present invention with reference to the drawings.
The first aspect of the present invention is:
An operation assist device for assisting a user's operation,
An assist mechanism;
A control device for controlling the operation of the assist mechanism;
An input interface for acquiring information on the user's sitting motion,
The assist mechanism is
An assist wear body having a waist restraint and a knee restraint, and a first actuator;
The assist wear body is attached to at least the lower half of the user,
The waist restraining portion is fixed to the user's waist,
The knee restraint is fixed to the user's knee,
The first actuator is disposed so as to connect between the waist restraining portion and the knee restraining portion, and is located at a portion of the assist wear main body corresponding to at least a position of the buttocks of the user. The actuator further has an elastic cylinder wound spirally,
At least one of the outer peripheral surface and the inner peripheral surface of the cylindrical body is provided with a spiral groove with the axial center of the cylindrical body as a central axis,
By controlling the pressure of the fluid in the hollow part of the cylindrical body, it expands and contracts in the radial direction and expands and contracts in the longitudinal direction.
The control device provides an operation assist device that supplies the fluid to the first actuator based on the information on the seating motion acquired by the input interface and controls expansion in a radial direction of the first actuator.
According to the first aspect, it is possible to prevent the actuator from being crushed by pressurizing and radially expanding the actuator disposed on the collar when seated, and to reduce damage and failure.
In a second aspect of the present invention, the control device performs control so as to maintain radial expansion due to pressurization of the first actuator even during a seating operation after the user is seated.
An operation assist device according to a first aspect is provided.
According to the second aspect, even during a seating operation after the user is seated, the actuator is prevented from being crushed by expanding in the radial direction by pressurizing the actuator, and damage and failure can be reduced.
According to a third aspect of the present invention, the assist mechanism further includes a second actuator positioned on the front side of the assist wear main body and arranged to connect between the waist restraint portion and the knee restraint portion. Have
The second actuator has an elastic cylindrical body wound in a spiral shape, and at least one of the outer peripheral surface and the inner peripheral surface of the cylindrical body, with the axis of the cylindrical body as a central axis, A groove is provided in a spiral shape, and expands and contracts in the longitudinal direction by controlling the pressure of the fluid in the hollow portion of the cylindrical body,
The control device controls the second actuator to pressurize the second actuator at the same timing as the first actuator, and pressurizes the second actuator so as to contract more than the first actuator.
An operation assist device according to the first or second aspect is provided.
According to the third aspect, when the first actuator is pressed and contracted to make the knee straight from the waist when sitting, the front second actuator is also pressed and the contracting force is applied to the front second. If the actuator is made larger than the first actuator on the buttock side and assisted so as to bend slightly forward, the seating operation is not hindered.
According to a fourth aspect of the present invention, the first actuator is
An actuator for a buttock located in a portion corresponding to the buttock of the user on the rear side of the assist wear body;
A waist actuator located in a portion corresponding to the waist of the user on the rear side of the assist wear body;
It is divided into a thigh back side actuator located in a portion corresponding to the back side of the user's thigh on the back side of the assist wear body,
An operation assist device according to any one of the first to third aspects is provided.
According to the fourth aspect, since the pressure of the lower back actuator and the thigh back actuator other than the buttocks actuator can be kept low, it is possible to reduce the risk due to pressure resistance such as liquid leakage. In addition, when the front actuator is provided, even if the buttock actuator is pressurized, if the lumbar actuator and the thigh back actuator are depressurized, the force to stretch the hip joint will not work. There is no need to increase the balance, the driving pressure of the front actuator can be reduced, and the energy consumption can be reduced.
According to a fifth aspect of the present invention, the input interface is configured to include any one of an acceleration sensor, an angle sensor, and a myoelectric sensor, and the seating operation is performed based on information from the sensor. Get information,
An operation assist device according to any one of the first to fourth aspects is provided.
According to the fifth aspect, each of the acceleration sensor, the angle sensor, and the myoelectric sensor can detect a characteristic movement during the sitting operation, and thus includes any one of them. Thus, the seating motion can be detected by detecting a characteristic motion before the seating is completed. By detecting the seating motion, the first actuator can be pressurized, and the effect as in the first aspect can be exhibited.
According to a sixth aspect of the present invention, as the input interface, after detecting a change in acceleration with an acceleration sensor, the angle sensor detects that the seating operation is performed when an inclination angle equal to or greater than a threshold value is detected.
An operation assist device according to any one of the first to fourth aspects is provided.
According to the sixth aspect, it is possible to prevent an unintended operation by erroneously detecting the start of seating. That is, with only the acceleration sensor or only the angle sensor, there is a possibility that an operation similar to the seating motion is erroneously detected as the start of the seating motion and assists in a forward leaning posture. In such a case, if the user does not intend, there is a risk of falling out of balance of the body. For example, when picking up an object by bowing or bending forward, it is dangerous if it is assisted to bend further. In order to prevent such a case reliably, such erroneous detection can be prevented by monitoring the transition of the two sensor outputs of the acceleration sensor and the angle sensor.
According to a seventh aspect of the present invention, as the input interface, a change in acceleration is detected by an acceleration sensor, and then a trunk forward tilt angle that is equal to or greater than a threshold value is detected by an angle sensor, and then an electromyogram that is equal to or greater than the threshold value is detected by an myoelectric sensor. When it is detected, the seating movement is acquired.
An operation assist device according to any one of the first to fourth aspects is provided.
According to the seventh aspect, by monitoring the transition of the three sensor outputs of the acceleration sensor, the angle sensor, and the myoelectric sensor, it is possible to further reduce the erroneous detection of the sitting operation. In addition, even after entering the seating operation, the user can move freely until the myoelectric sensor detects an electromyogram above the threshold, that is, immediately before the seating. It is possible to migrate and respond to unexpected situations.
(Embodiment 1)
Hereinafter, an operation assist device according to a first exemplary embodiment of the present invention will be described in detail with reference to the drawings.
It should be noted that each of the embodiments described below shows a comprehensive or specific example. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, order of steps, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept are described as optional constituent elements.
(overall structure)
First, the motion assist device is a device capable of assisting the user 100 in walking, standing up and sitting, and is disposed on the rear side of the user 100 and includes an assist mechanism 20 having the actuator 1 and an assist mechanism. The control part 29 as an example of the control apparatus which controls operation | movement of 20 is provided. In this embodiment, as an example, the arrangement of the actuator is assumed to be walking assist, but is not limited thereto.
(Actuator)
First, the actuator 1 used for the assist mechanism 20 will be described. The actuator 1 is configured to find a problem of a conventional McKibben type actuator and solve it as follows.

(Challenges of McKibben actuator)
The present inventor has found that the following problems occur with respect to the McKibben type actuator described in the “Background Art” column.

  Since the McKibben actuator is composed of a rubber tube, it originally has flexibility in the bending direction. However, this flexibility decreases as the internal pressure of the rubber tube increases, and the rigidity against bending increases. It is considered that the bending rigidity is increased because the actuator is bent to cause a volume change in the internal space of the rubber tube. In order to bend the actuator, it is necessary to compress the fluid in the internal space and generate a deformation corresponding to the compressive force in the rubber tube. The force required for bending increases as the pressure in the internal space increases.

  Such a characteristic is useful in an object gripping operation utilizing bending rigidity, but becomes a problem when an actuator is provided in clothes-like assist wear, for example. That is, when the actuator is bent along a human body shape such as an arm or a leg, if the fluid is pressurized in order to extend or contract the actuator, not only the axial force but also the force to eliminate the bending along the human body shape Occur. Therefore, by providing this actuator, the force in the axial direction can be assisted, but there is a problem that free movement in the bending direction is hindered.

  In order to solve such a problem, the present inventor has previously proposed an actuator 1 having an actuator structure having the following structure. That is, the actuator structure is an actuator structure that expands and contracts in the longitudinal direction by controlling the pressure of the fluid in the hollow portion of the cylinder, and is an elastic cylinder wound in a spiral shape. And at least one of an outer peripheral surface and an inner peripheral surface of the cylindrical body is provided with a groove spirally with the axial center of the cylindrical body as a central axis.

According to this configuration, when a fluid is filled in the hollow portion of the cylindrical body and the pressure thereof is changed, the cylindrical body is elastically deformed outward or inward and expands or contracts in the radial direction, so that the groove of the cylindrical body Twist occurs along the spiral. By generating this twist, the actuator structure having a spirally wound shape can be expanded and contracted with respect to the major axis direction. Further, when an external force is applied in a direction in which the actuator structure is bent with respect to the major axis direction, a location where the volume inside the cylinder increases due to a twist in the predetermined direction of the cylinder and a twist in a direction opposite to the predetermined direction. Both the location where the volume inside the cylinder is reduced can be made. Therefore, the volume change as a whole inside the cylinder is reduced, and the actuator structure can be easily bent.
Such an arrangement will be described below in detail with reference to the drawings. After that, the actuator having such an actuator structure that can be expanded and contracted and allows free movement in the bending direction is seated. An operation assist device according to the first embodiment of the present invention that can be prevented from being crushed at the time will be described.

  First, the actuator 1 will be described with reference to the drawings.

(Actuator structure)
First, the overall configuration of the actuator 1 will be described with reference to FIG. The actuator 1 is one that expands or contracts in the radial direction and expands and contracts in the longitudinal direction by controlling the fluid pressure in the hollow portion of the cylinder, and includes the actuator structure 2, the pressure source 3, and the like. And a pipe 4.

  The actuator structure 2 has a shape in which a hollow cylinder 10 is spirally wound around the long axis direction. The cylinder 10 is filled with a fluid such as water. The upper part of the actuator structure 2 is fixed to a fixture (not shown), and the upper end thereof is connected to the pipe 4. The lower end of the actuator structure 2 is sealed by caulking or the like. The configuration of the actuator structure 2 will be described in detail later.

  The pressure source 3 increases or decreases the pressure inside the cylinder 10 of the actuator structure 2 by putting fluid into and out of the actuator structure 2 through the pipe 4, and moves the actuator structure 2 along the long axis direction. Extend and retract.

  For example, a syringe pump (reciprocating pump) is used as the pressure source 3. A syringe pump is a pump having a cylindrical syringe such as a syringe, a movable pusher, and a control unit that controls the position of the pusher. The pressure in the syringe is reduced with a pusher, and the fluid is collected in the syringe. By operating the syringe pump, it is possible to adjust the amount or pressure of the fluid filled in the cylinder 10 of the actuator structure 2.

  The pipe 4 is a tubular member that connects the pressure source 3 and the actuator structure 2 and serves as a fluid inflow / outflow path. Note that when the pressure source 3 and the actuator structure 2 are directly connected, the pipe 4 may not be used. Further, the piping 4 may be branched and a plurality of actuator structures 2 may be connected to one pressure source 3.

  Next, the actuator structure 2 will be described.

  FIG. 2 is a view showing a part of the cylinder 10 of the actuator structure 2, and FIG. 3 is a cross-sectional view of the cylinder 10 of the actuator structure 2.

  The actuator structure 2 has a shape in which a hollow cylinder 10 having elasticity is spirally wound around the long axis direction. Specifically, the cylindrical body 10 is wound spirally around the axis A1 in the major axis direction of the actuator structure 2. On the outer peripheral surface 10b of the cylindrical body 10, a plurality of grooves c are provided in a spiral shape with the axial center A2 of the cylindrical body 10 as the central axis. In the first embodiment, the spiral of the cylinder 10 is clockwise with respect to the axis A1, and the spiral of the groove c is clockwise with respect to the axis A2. That is, the spiral winding directions of the cylinder 10 and the groove c are the same.

  As shown in FIG. 3, the cylindrical body 10 is disposed on the outer side of the cylindrical body 10 and has a cylindrical first elastic member 11, and is disposed on the inner side of the elastic member 11 and is more flexible than the first elastic member 11. And a cylindrical (tubular) second elastic member 12 having high properties. The second elastic member 12 is hollow, and the fluid 5 is filled in the hollow portion (inside the inner peripheral surface 12a).

  The first elastic member 11 is provided with a plurality of through holes 11c penetrating the inner peripheral surface 11a and the outer peripheral surface 11b. The second elastic member 12 is disposed in contact with the inner peripheral surface 11a inside the first elastic member 11, and closes the through hole 11c. Therefore, the groove c is formed by the side surface of the through hole 11 c of the first elastic member 11 and the surface (outer peripheral surface 12 b) of the second elastic member 12. In addition, the 1st elastic member 11 and the 2nd elastic member 12 are not adhere | attached.

  Moreover, the 1st elastic member 11 has the some bone part b located between the groove | channel c adjacent to the circumferential direction in the circumferential direction. The bone portion b has a circular cross section in the radial direction orthogonal to the central axis of the axis A2, and is provided at intervals in the circumferential direction. The bone part b is composed of four bone parts b in this cross section, and these bone parts b are spirally wound around the axis A2 so that the four grooves c are formed around the axis A2. It is provided in a spiral.

  The first elastic member 11 is disposed outside the second elastic member 12, and is formed by an inner peripheral surface 11a of the first elastic member 11 and a side surface of the groove c (through hole 11c). Is chamfered. In FIG. 3, the ridgeline is rounded, but it may be formed in a tapered shape.

  As described above, a member having higher flexibility than the first elastic member 11 is used as the second elastic member 12. A member having high flexibility means a soft member as a material or a structurally soft member, for example, a member that is easily formed by being thinly formed or formed into a wave shape.

  For example, nylon is used as the material of the first elastic member 11, and silicon rubber is used as the material of the second elastic member 12, for example. However, it is not limited to these materials, and various resin materials or metal materials can be used. These elastic members 11 and 12 are appropriately selected in consideration of required pressure resistance, flexibility, or resistance to the fluid 5 (chemical resistance, solvent resistance, or oil resistance). For example, a lightweight actuator structure 2 can be obtained by using a resin material for the elastic members 11 and 12. Further, by using a highly rigid engineering plastic or metal material, the actuator structure 2 can be operated at a high pressure and a low flow rate, and the loss accompanying the flow of the fluid 5 can be reduced.

  In addition, the pipe 4 of the actuator 1 described above has a pressure resistance higher than that of the elastic members 11 and 12 in order to increase the responsiveness when the actuator structure 2 is operated.

  4 is a view showing the cylinder 10 of the actuator structure 2 in a straight line, and FIG. 5 is a longitudinal sectional view of the cylinder 10 shown in FIG.

As shown in FIGS. 4 and 5, the cylindrical body 10 has a multi-slot structure, and specifically, four grooves c (c1, c2, c3, c4) and four bone parts b (b1, b2). , B3, b4). The grooves c1, c2, c3, and c4 are parallel to each other, and the width of each is constant. The interval between adjacent grooves c (for example, the interval between the grooves c1 and c2) is appropriately designed according to the number of grooves c. Bone b1, b2, b3, b4 be parallel to each other, which is the width of each of _{w b} constant. The thickness t _b of the bone part b is smaller than the width w _b of the bone part b.

  These grooves c are provided so that the inclination θ is less than 45 ° with respect to the axis A2 of the cylindrical body 10 when the pressure applied by the fluid is zero. Moreover, the diameter d of the cylinder 10 is, for example, 3.6 mm, and the spiral pitch p2 of the groove c is, for example, 10 mm. By setting the inclination θ of the groove c to less than 45 °, the spiral pitch p2 of the groove c is larger than the outer peripheral length πd of the cylindrical body 10 (the outer peripheral length of the first elastic member 11 in the first embodiment). Is set.

  Next, a method for driving the actuator 1 will be schematically described.

  6 is a flowchart showing a driving method of the actuator 1, and FIGS. 8A and 8B are schematic views showing expansion and contraction along the long axis (axial center) A1 direction of the actuator structure 2. FIG. 8A and 8B, the illustration of the groove c is omitted.

  The driving method of the actuator 1 includes step S1 (a) for preparing the actuator 1, and steps S2 and S3 (b) for increasing / decreasing the length of the actuator structure 2 in the long axis direction (long axis A1 direction). ing.

  First, before preparing the actuator 1 and pressurizing the fluid 5 inside the cylinder 10, the actuator structure 2 is in a steady state as shown in FIG. 8A (step S1 in FIG. 6). The steady state is a state in which preload is applied to the fluid 5 inside the cylindrical body 10, and the length of the actuator structure 2 is a length obtained by adding a contraction due to the preload and a deformation due to the external force to the natural length. .

  Next, in the state shown in FIG. 8A, the fluid 5 is pressurized with, for example, 0.5 MPa using the pressure source 3, and the fluid 5 is further supplied into the cylinder 10 of the actuator structure 2. Thereby, as shown in FIG. 8B, the actuator structure 2 is contracted in the direction of the long axis A1 (step S2 in FIG. 6).

  Next, the fluid 5 is depressurized by the pressure source 3 to extend the actuator structure 2 in the direction of the axis A1 and return to the original length (step S3 in FIG. 6). By repeating these steps, the length of the actuator structure 2 is increased or decreased (stretched). In addition, only one operation | movement may be sufficient as the operation | movement of expansion or contraction, and you may reverse the order. Moreover, you may repeat the operation | movement of only expansion or contraction in multiple times.

  Next, the drive mechanism of the actuator structure 2 will be described.

  FIG. 7A is a cross-sectional view showing the bone portion b of the first elastic member 11 before the fluid 5 inside the cylindrical body 10 is pressurized. FIG. 7B is a cross-sectional view showing the deformation of the bone portion b of the first elastic member 11 after pressurizing the fluid 5 inside the cylindrical body 10.

  7A and 7B are views of one turn of the bone part b as viewed from the direction of the axis A2.

  Before pressurizing the fluid 5, the radius of the bone portion b is r as shown in FIG. 7A. When the fluid 5 is pressurized, the pressure transmitted through the second elastic member 12 of the cylindrical body 10 causes the first elastic member 11 of the cylindrical body 10 to expand (deform) in the radial direction, and accordingly, FIG. As shown, the radius of the bone portion b is r + Δr. At this time, a twist of an angle φ = 2πΔr / (r + Δr) occurs in the bone portion b per turn. This twist causes the entire cylindrical body 10 mainly composed of the first elastic member 11 to be twisted about the center of the axis A2.

  In the configuration of FIG. 2, the groove c of the cylindrical body 10 is right-handed with respect to the axis A <b> 2 and the actuator structure 2 is right-handed with respect to the axial center A <b> 1. As shown in FIG. 8B, the actuator structure 2 acts to contract in the direction of the axis A1.

  That is, the cylindrical body 10 is generally twisted in the left-handed direction around the axis A2 as a result of expansion in the radial direction due to pressurization. Since the actuator structure 2 is right-handed about the axis A1, when focusing on the right side of the actuator structure 2 shown in FIG. 8B, the cylinder 10 is left-handed so that the front side rotates in the direction of the solid arrow. Twisted in the direction. On the other hand, when attention is paid to the left side of the actuator structure 2, the cylindrical body 10 is twisted in the left-handed direction so that the heel side rotates in the direction of the dashed arrow. Therefore, the twist generated over the entire length of the cylindrical body 10 decreases the pitch angle α of the cylindrical body 10 (see an angle α that is half of “2α” in FIG. 8A) (the helical pitch p1 of the cylindrical body 10 is decreased). ), The length in the major axis direction of the actuator structure 2 becomes shorter than the length in the steady state.

  Then, when the pressurization of the fluid 5 is released, the deformation and twist in the radial direction of the cylindrical body 10 are restored by the elastic force of the first elastic member 11 and the second elastic member 12, and the actuator structure 2 is restored. The length in the major axis direction of this also returns to the original steady state length.

  When the cylinder 10 of the actuator structure 2 expands (deforms), the groove c located on the outer peripheral side of the cylinder 10 tries to expand (deform) not only in the radial direction but also in the axis A2 direction. However, by setting the inclination θ of the groove c to less than 45 ° as in the first embodiment (by making the helical pitch p2 larger than the outer peripheral length πd of the cylindrical body 10), Even if the groove c expands in the width direction, the cylindrical body 10 is sufficiently twisted, so that the actuator structure 2 can be sufficiently contracted in the major axis direction.

  Next, a case where an external force is applied to the actuator structure 2 to cause bending deformation will be described. The actuator structure 2 according to the first embodiment can be bent and deformed by the elasticity of the actuator structure 2 itself regardless of the pressure of the fluid 5 even when an external force is applied from the lateral direction with respect to the major axis direction. There are also features.

  9A is a schematic diagram showing the actuator structure 2 before an external force is applied, and FIG. 9B is a schematic diagram showing a bent state of the actuator structure 2 after the external force is applied. 9A and 9B, the illustration of the groove c is omitted.

  As shown in FIG. 9B, assuming a case where an external force in the vertical direction is applied to the axis A1 of the actuator structure 2 to bend and deform, one pitch angle α1 of the cylindrical body 10 becomes smaller and the other The pitch angle α2 increases. Thereby, the right side of the cylinder 10 is twisted in the left-handed direction so that the front side rotates in the direction of the solid line arrow, and the left side of the cylinder 10 is twisted in the right-handed direction so that the side of the cylinder 10 rotates in the direction of the broken line arrow.

  When twist occurs in the direction opposite to the spiral winding direction of the groove c, the diameter of the cylindrical body 10 increases and the volume inside the cylindrical body 10 increases. On the other hand, when the twist occurs in the same direction as the spiral winding direction of the groove c, the diameter of the cylinder 10 is reduced, and the volume inside the cylinder 10 is reduced. In the first embodiment, since the increase and decrease in the volume inside the cylinder 10 occur simultaneously, the volume change as a whole inside the cylinder 10 is reduced, and the actuator structure 2 can be easily bent. Can do.

That is, the rigidity when the actuator structure 2 is bent and deformed does not substantially depend on the pressure acting on the fluid 5, and the rigidity of the actuator structure 2 itself is dominant. Therefore, if the actuator structure 2 is made of a flexible material, the actuator structure 2 that can be easily bent and deformed can be realized.
(Configuration of motion assist devices other than actuators)
Hereinafter, the motion assist device 101 using the actuator structure 2 according to the first embodiment will be described with reference to the drawings. When the operation assisting device 101 is pressurized, a force that contracts in the longitudinal direction and a force that expands in the radial direction (a force that resists crushing) work simultaneously.
The motion assist device 101 includes an assist pant 20 as a specific example of assist wear as an example of an assist mechanism, a control unit 29 that functions as an example of a control device that controls the operation of the assist pant 20, and a seating of the user 100. Input interfaces 27 and 28 for acquiring operation information are provided.
The assist pant 20 includes at least an assist pant body 21 as an example of an assist wear body having a waist restraining part 21a and a knee restraining part 21b, and second and third actuators 1B and 1D.
The assist pants body 21 is worn by the user 100 at least on the lower body.
The waist restraining part 21a is a ring-like member such as rubber or a belt-like member arranged on the upper side of the assist pant body 21, and is detachably fixed to the waist 100a of the user 100.
The knee restraint portion 21b is a ring-like member such as rubber or a belt-like member disposed below the waist restraint portion 100a of the assist pant body 21 and is detachably fixed to the knee 100b of the user 100. The waist restraining part 21a and the knee restraining part 21b are fixed to the waist 100a and the knee 100b so as to be detachable with rubber or the like, and give the assist force from the second and third actuators 1B and 1D to the user 100. This makes it possible to assist seating operations.
Each of the second and third actuators 1B and 1D is located in the range from the waist region including the portion corresponding to at least the buttock 100c of the user 100 on the rear side of the assist pant body 21 to the back side of the thigh and the waist restraint. It arrange | positions so that between the part 21a and the knee restraint part 21b on either side may each be connected, and is corresponded to the actuator 1 respectively. The second actuator 1B has one or a plurality of actuator structures 22B that expand or contract in the radial direction and expand and contract in the longitudinal direction by controlling the pressure of the fluid in the hollow portion of the cylindrical body 10, An upper end of the second actuator structure 22B is connected to the waist restraining portion 21a, and a lower end is connected to the left knee restraining portion 21b so as to cover the left heel portion 100c up and down. The third actuator 1D includes one or a plurality of actuator structures 22D that expand or contract in the radial direction and expand and contract in the longitudinal direction by controlling the fluid pressure in the hollow portion of the cylindrical body 10, The upper end of the third actuator structure 22D is connected to the waist restraining portion 21a, the lower end is connected to the right knee restraining portion 21b, and is arranged so as to cover the right buttocks 100c up and down. Each of the actuator structures 22B and 22D has the same structure and the same action as the actuator structure 2 described above, and has an elastic cylinder 10 wound in a spiral shape. At least one of the outer peripheral surface and the inner peripheral surface of the cylindrical body 10 is provided with a groove c spirally with the axis A1 of the cylindrical body 10 as the central axis.
The input interface functions as, for example, a seating movement information acquisition unit, and can be specifically configured with various sensors such as the movement sensor 27 and / or the myoelectric sensor 28. The motion sensor 27 and / or the myoelectric sensor 28 are disposed in the assist pants main body 21.
Based on information on the sitting motion acquired by the input interface, for example, the motion sensor 27 and / or the myoelectric sensor 28, the control unit 29 is at least when the user 100 is seated, and in some cases even during the seating motion. Fluid is supplied to the second and third actuator structures 22B and 22D to pressurize the second and third actuator structures 22B and 22D to control the expansion in the radial direction.

First, the overall configuration of the assist pants 20 of the motion assist device 101 according to the first embodiment will be described with reference to FIGS. 10A to 11. 10A and 10B are diagrams illustrating a case where the user 100 wears the assist pants 20 on the lower body. FIG. 10A is a perspective view of the assist pants 20 viewed from the front side, and FIG. 10B is a perspective view of the assist pants 20 viewed from the rear. In these drawings, only the lower half of the user 100 is shown for easy understanding. FIG. 11 is a block diagram of control of the motion assist device 101.
The motion assist device 101 shown in FIGS. 10A and 10B includes assist pants 20, a motion sensor 27, a myoelectric sensor 28, and a control unit 29.
The assist pants 20 includes an assist pant body 21, a waist restraint portion 21a, a pair of knee restraint portions 21b, and first, second, third, and fourth actuators 1A, 1B, 1C, and 1D. ing.
The assist pants body 21 is worn by the user 100 on the lower body. A waist restraining portion 21a is fixed to the upper end edge of the assist pants body 21, and can be attached to and detached from the waist 100a of the user 100 and the waist 100a can be restrained. A pair of knee restraint portions 21b are fixed to a pair of lower end edges of the assist pants body 21, and can be attached to and detached from the left and right knees 100b of the user 100, and the left and right knees 100b can be restrained.
The first, second, third, and fourth actuators 1A, 1B, 1C, and 1D connect the waist restraint 21a and the knee restraint 21b between the waist restraint 21a and the knee restraint 21b, respectively. Is arranged.
The first, second, third, and fourth actuators 1A, 1B, 1C, and 1D include the left front side, left rear side, right front side, and right rear side actuator structures 22A, 22B, 22C, and 22D, and the front side And rear pressure sources 23A and 23B, front and rear pipes 24A and 24B, and front and rear valves 25 and 26. The left front side, left rear side, right front side, and right rear side actuator structures 22A, 22B, 22C, and 22D are disposed between the waist restraint portion 21a and the knee restraint portion 21b.
Specifically, the actuator structures 22A and 22C on the left front side and the right front side are vertically (or vertically) between the waist restraint portion 21a on the front surface of the assist pants body 21 and the left and right knee restraint portions 21b. It is arranged along each. The left rear side and right rear side actuator structures 22B and 22D extend along the vertical direction (or vertical direction) between the waist restraint portion 21a on the rear surface of the assist pants body 21 and the left and right knee restraint portions 21b. Respectively. Therefore, when the user 100 wears the assist pants 20 on the lower body, the actuator structures 22A and 22C are in contact with each other between the front abdomen of the user 100 and the left and right knees 100b. It is arranged along the vertical direction (or vertical direction) on the front side. The actuator structures 22B and 22D are arranged along the vertical direction (or the vertical direction) on the rear side of the assist pants body 21 so as to be in contact between the waist 100a on the back side of the user 100 and the left and right knee soles. ing.
The actuator structure 22A is connected to a front pressure source 23A via a front pipe 24A, and a front valve 25 is disposed in the front pipe 24A. Similarly, the actuator structure 22B is connected to a rear pressure source 23B via a rear pipe 24B, and a rear valve 26 is arranged in the rear pipe 24B. For example, a syringe pump (reciprocating pump) is used as the pressure sources 23A and 23B.
In FIG. 10A, the motion sensor 27 is disposed near the center of the waist on the rear side of the assist pant body 21. The motion sensor 27 includes an acceleration sensor 27a that can detect a change in acceleration (for example, rising of FIGS. 12B and 16B), an angle sensor 27b that can detect the trunk forward tilt angle, or a gyro that can detect the trunk forward tilt angle. The sensor 27c is configured to sense an intention such as sitting, standing up, and walking.
The myoelectric sensor 28 is disposed on the front side of the thigh of the left leg of the assist pants main body 21. Specifically, the myoelectric sensor 28 is arranged, for example, at a position where the myoelectric potential of the outer vastus muscle is detected, and is configured so as to sense the intention of the operation, like the operation sensor 27. Although it is desirable that the myoelectric sensor 28 is also provided on both legs, the illustration of the myoelectric sensor 28 on the right leg side is omitted in FIG. Here, the assist pants body 21 is illustrated as short pants, but in the case of long pants, the myoelectric sensor 28 is arranged at a position where the myoelectric potential of the anterior tibial muscle is detected. May be.
As an example, the control unit 29 is disposed near the center of the waist on the front side of the assist pant main body 21. The control unit 29 receives information from the motion sensor 27 and the myoelectric sensor 28, and supplies the front and rear pressure sources 23 </ b> A and 23 </ b> B and the front and rear valves 25 and 26. It is connected. Therefore, the control unit 29 grasps the operation of the user 100 based on the signal from the motion sensor 27 or the myoelectric sensor 28, opens / closes the front and rear valves 25, 26, and the front side. The pressure of the pressure sources 23A and 23B for the rear side is controlled. The sensor for detecting the intention of the user 100 may be a combination of the motion sensor 27 and the myoelectric sensor 28 as in the first embodiment, or may be either one.

  The pressure source 23A for the front side draws fluid into and out of the actuator structures 22A and 22C for the left front side and the right front side via the pipe 24A for the front side, so that the actuator structures 22A and 22C for the left front side and the right front side are provided. Is increased or decreased to expand and contract the left and right front actuator structures 22A and 22C. Specifically, by pressing the left and right front actuator structures 22A and 22C, the left front and right front actuator structures 22A and 22C are contracted, and an assist force is generated in the direction of bending the hip joint. To do. In addition, the pressure source 23B for the rear side draws fluid into and out of the left rear side and right rear side actuator structures 22B and 22D via the rear side pipes 24B and 22D, so that the left rear side and the right side The pressure inside the rear actuator structures 22B and 22D is increased or decreased to expand and contract the left rear and right rear actuator structures 22B and 22D. Specifically, by pressing the left rear and right rear actuator structures 22B and 22D, the left rear and right rear actuator structures 22B and 22D are contracted to extend the hip joint. Generate assist force.

(Sitting operation and actuator control)
Next, the operation when the user 100 wears the assist pants 20 of the first embodiment and sits on the chair 103 and the like, and the control of the actuator 1 will be described. Here, the first actuator 1A includes an actuator structure 22A, a pressure source 23A, a pipe 24A, and a valve 25, and the second actuator 1B includes an actuator structure 22B and a pressure source 23B. And a pipe 24 </ b> B and a valve 26. The third actuator 1C includes an actuator structure 22C, a pressure source 23A, a pipe 24A, and a valve 25. The fourth actuator 1D includes an actuator structure 22D, a pressure source 23B, and a pipe. 24B and a valve 26 are provided.

FIG. 12A is an explanatory view showing a seating operation. (A) is a standing posture of the user 100, (b) is a posture at the start of the sitting motion of the user 100, (c) is a posture during the sitting motion of the user 100, and (d) is a posture immediately after the user 100 is seated. Each is shown. FIG. 12B shows the relationship between the acceleration detected by the motion sensor 27 and time in each posture. The solid line 33 indicates the vertical acceleration, and the dotted line 34 indicates the horizontal acceleration. FIG. 12C shows the trunk forward tilt angle (AFI) shown in the posture (c) of FIG. 12A and the lateral vastus muscle (VL) and anterior tibial muscle (TA) detected by the myoelectric sensor 28 in each posture. The change with time of each myoelectric potential is shown, the solid line 35 is the trunk forward tilt angle, the dotted line 36 is the myoelectric potential of the outer vastus muscle (VL), and the alternate long and short dash line 30 is the myoelectric potential of the anterior tibial muscle (TA). Is shown. Note that the trunk forward tilt angle is an angle formed by the vertical direction and the surface of the back restraint portion 21a on the rear side of the assist pants main body 21. For example, the motion sensor 27 arranged on the back restraint portion 21a on the rear side is gyroscopic. It can be detected by using a sensor.
In FIG. 12C, as an example, after detecting a peak of the trunk forward tilt angle (AFI) 35 that is equal to or higher than the threshold 35a, a peak that is equal to or higher than the threshold 36a of the myoelectric potential of the lateral vastus muscle (VL) 36, or anterior tibial muscle ( TA) When the peak of the myoelectric potential threshold value 30a or higher is detected, it is shown that the control unit 29 can determine the seating.
FIG. 13 is a flowchart showing the respective driving methods of the first and third actuators and the second and fourth actuators when sitting. FIG. 14B is an explanatory diagram showing temporal changes in pressure applied to the actuator structure 22A (22C) and the actuator structure 22B (22D). FIG. 14C is an explanatory diagram showing opening and closing of the valves 25 and 26. For comparison with FIGS. 14B and 14C, the same explanatory diagram as FIG. 12A is shown as FIG. 14A. 14B and 14C, the dotted line 31 indicates the pressure of the actuator structure 22A, the solid line 32 indicates the pressure of the actuator structure 22B, the dotted line 37 indicates opening and closing of the valve 25, and the solid line 38 indicates opening and closing of the valve 26, respectively.
Here, the determination by the control unit 29 of the posture (b) that is the starting point of control is, for example, when the waist moves (accelerates) in the horizontal direction and then moves (accelerates) in the vertical direction. Characteristic movement is detected using the motion sensor 27 and determined by the control unit 29. At this time, if the posture is determined by the control unit 29 with reference to the trunk forward tilt angle, the accuracy of the determination by the control unit 29 is improved. In addition, since the influence of the impact at the time of sitting appears on various sensors, the posture (d) can be easily detected by the control unit 29 using information resulting from the influence of the impact on the various sensors.

  The driving method of each actuator 1 (1A, 1B, 1C, 1D) at the time of sitting includes the steps of pressurizing the rear actuator structures 22B, 22D, the step of supporting the sitting operation, and the posture after sitting. And a step for setting.

  Before entering the seating operation, the steady state is the same as in step S1 of FIG. 6, and the control unit 29 applies preload to the front actuator structures 22A and 22C and the rear actuator structures 22B and 22D, respectively. The valve 25 and the valve 26 are in a closed state. 14A, when the control unit 29 determines that the seating intention has been detected based on the detection information of the motion sensor 27, the control unit 29 opens the valve 25 and the valve 26, and the actuator structures 22A and 22C. The actuator structures 22B and 22D are pressurized and expanded in the radial direction (step S21 in FIG. 13). Then, the actuator structures 22B and 22D are sufficiently pressurized and expanded in the radial direction, and then the valve 26 is closed by the control unit 29 (step S22 in FIG. 13).

Here, the reason why the actuator structures 22B and 22D are pressurized and expanded in the radial direction is to prepare for an impact at the time of sitting. The actuator structures 22B and 22D are pressurized and the valve 26 is controlled by the controller 29. By closing with, the actuator structures 22B and 22D expanded in the radial direction have a cushion function. At this time, if only the actuator structures 22B and 22D are pressurized and expanded in the radial direction, the actuator structures 22B and 22D contract along the longitudinal direction, and force acts in the direction of extending the hip joint. Operation is disturbed. Therefore, in step S21, the actuator structures 22A and 22C are simultaneously pressurized and contracted along the longitudinal direction. Further, in order to take a forward leaning posture when sitting, the pressure of the actuator structures 22A and 22C is set higher than the pressure of the actuator structures 22B and 22D. With this setting, the actuator structures 22A and 22C and the actuator structures 22B and 22D balance with each other in a state in which the actuator structures 22B and 22D are extended. Become. Such control utilizes the characteristic that the actuator structures 22A and 22C and the actuator structures 22B and 22D generate a static spring force proportional to the strain as well as a generated force proportional to the applied pressure. Yes. Further, in the assist pants 20 of the first embodiment, the sitting structure is supported by changing the posture in which the force generated by the actuator structures 22A and 22C and the actuator structures 22B and 22D can be balanced. Yes. Therefore, the assist force increases as the posture deviates from that set by the assist pants 20.
19A and 19B are explanatory diagrams showing forces applied to the user 100 by the actuator structures 22A to 22D in the posture (b) shown in FIG. 12A. FIG. 19A shows the force received from the actuator structure 22A, and FIG. 19B shows the force received from the actuator structure 22B. As shown in FIG. 19A, when the actuator structure 22A contracts, a force is applied in the direction in which the hip joint bends. As shown in FIG. 19B, when the actuator structure 22B contracts, a force is applied in the direction in which the hip joint extends.

After the valve 26 is closed, the pressure of the actuator structures 22B and 22D remains substantially constant and remains constant, and the force continues to be exerted in the direction of contracting the actuator structures 22B and 22D. By adjusting the pressures of 22A and 22C by the control unit 29, the seating operation is supported. In an example of the sitting operation, as shown in FIG. 12A, from the posture (a) to immediately before the posture (c), the buttock is protruded backward, and the posture is gradually tilted forward for balance. Then, while raising the body between the posture (c) and the posture (d), the buttocks fall toward the chair 103. For example, in order to support this operation, control is performed such that the pressure of the actuator structures 22A and 22C is gradually increased and the pressure is decreased with the posture (c) as a boundary (step S23 in FIG. 13). Determination of posture (c) by the control unit 29 is performed by the control unit 29 from the acceleration or the trunk inclination angle obtained by the motion sensor 27 or the myoelectric potential detected by the myoelectric sensor 28. Note that if the posture (c) is a deep forward leaning posture, the center of gravity remains in front and the speed of the seating operation becomes slow. If the control unit 29 determines that the seating operation is too fast, the control unit 29 may control the actuator structures 22A and 22C to increase the pressure so as to reduce the speed.
When the control unit 29 performs the above-described control, the seating operation speed is reduced, or a predetermined pressure for preventing crushing, that is, a crushing operation pressing force (second pressing force) is applied to the collar unit actuator. The structures 22A to 22D are pressurized and expanded in the radial direction. Since the actuator structures 22B and 22D expanded in the radial direction serve as cushions, it is possible to mitigate the impact at the time of sitting. Accordingly, the actuator structures 22B and 22D can be prevented from expanding in the radial direction and the actuator structures 22B and 22D can be prevented from being crushed, and the actuator structures 22B and 22D can be prevented from being crushed and damaged by a seating impact. be able to.

When the sitting is completed, the sitting state is maintained until the control unit 29 determines that the intention to stand is detected next. At this time, if the pressures of the actuator structures 22A and 22C and the actuator structures 22B and 22D are kept high, the hip joint stiffness remains high while sitting, resulting in a feeling of pressure. For this reason, the pressure set by the control unit 29 in preparation for the impact of the seating is set so that the rear actuator structures 22B and 22D are not crushed after the seating (for example, the rear actuator structure). Then, the valves 25 and 26 are closed (step S24 in FIG. 13).
By such control by the control unit 29, it is possible to prevent the rear actuator structures 22B and 22D from being crushed and damaged while being seated while reducing the feeling of pressure during seating.
From the above, in the assist pants 20, it is possible to prevent the rear actuator structures 22 </ b> B and 22 </ b> D arranged in the buttock from being crushed and damaged by an impact during sitting or a load during sitting. . Further, since the actuator structures 22B and 22D on the rear side serve as cushions, they also serve as cushioning materials for the user 100.

In addition, the pressure control in the control unit 29 of the actuator structures 22A and 22C and the actuator structures 22B and 22D shown in FIGS. 13 to 14C is compared in the operation between the posture (b) and the posture (d). The case where it is performed in a short time or the case where fine control is not performed is assumed. However, when the response speed of the actuator 1 is sufficiently high compared to the seating operation and the posture during the seating operation can be grasped sequentially, the pressures of the actuators 22B and 22D immediately before the seating as shown in FIGS. 15B and 15C. It may be controlled by the control unit 29 so as to increase. Note that FIG. 15A, which is shown for comparison with FIGS. 15B and 15C, is the same explanatory view as FIG. 12A.
If it does in this way, the freedom degree of operation of user 100 will improve. In the control shown in FIG. 14B and FIG. 14C, when entering the seating operation, the user 100 operates in accordance with the movement of the assist pants 20, but in the control shown in FIG. 15B and FIG. The assist pants 20 have low rigidity, and the user 100 can move freely. Therefore, since the user 100 can stop in the middle of the sitting operation or can move to another operation in the middle, it is possible to cope with an unexpected situation.

Specifically, until the posture (c), no assist is performed, and the actuator structures 22A, 22C and 22B, 22D are left in the preload (step S61 in FIG. 15D). Thereafter, the state immediately before sitting is determined by the control unit 29 using the myoelectric sensor 28 or the like, and the valves 25 and 26 are opened by the control unit 29 to pressurize the actuator structures 22A, 22C and 22B and 22D. 26 is closed (step S62 in FIG. 15D). After the seating, the valves 25 and 26 are opened again, the pressures of the actuator structures 22A, 22C, 22B and 22D are lowered, and the valves 25 and 26 are closed (step S63 in FIG. 15D). Note that step S63 may be omitted.
At this time, in order to quickly increase the pressure between postures (c) and (d), the preload may be increased by one step at the time of posture (b). At this time, if the valve 26 is kept open after the preload of the actuator structures 22B and 22D is increased by one step and before the pressure is further increased immediately before the seating, the pressure is immediately increased immediately before the seating. Can do. Alternatively, pressure vessels are arranged between the valve 25 and the pressure source 23A and between the valve 26 and the pressure source 23B, respectively, and the valves 25 and 26 are closed in the posture (b), and pressure is applied by the pressure sources 23A and 23B. The pressure of the container may be increased, and the pressure of the actuator structures 22A, 22C, 22B, and 22D may be increased at a stroke when the valves 25 and 26 are opened in the posture (c).

  When the above control is performed by the control unit 29, the driving pressure of the actuator structures 22A and 22C during the sitting operation is reduced, the degree of freedom of the user operation is improved, and the risk due to pressure resistance performance such as liquid leakage Can also be reduced.

(Standing motion and actuator control)
Next, the operation when the assist pants 20 of the first embodiment is worn and standing and the control of the actuator 1 will be described.

FIG. 16A is an explanatory view showing a standing motion, where (e) is a sitting posture, (f) is a posture at the start of the standing motion, (g) is a posture immediately after the buttocks are separated from the chair 103, (h ) Shows the posture just before standing up. FIG. 16B shows the relationship between the acceleration detected by the motion sensor 27 in each posture and time, and as in FIG. 12A, the solid line 33B shows the acceleration in the vertical direction and the dotted line 34B shows the acceleration in the horizontal direction. FIG. 16C shows temporal changes between the trunk forward inclination angle (AFI) shown in the posture (g) of FIG. 16A and the myoelectric potential of the outer vastus muscle detected by the myoelectric sensor 28 in each posture. The solid line 35B indicates the trunk forward tilt angle, and the dotted line 36B indicates the myoelectric potential.
FIG. 17 is a flowchart showing a driving method of the first actuator set and the second actuator set at the time of standing. FIG. 18B is an explanatory diagram illustrating changes in pressure applied to the actuator structures 22A and 22C and the actuator structures 22B and 22D. FIG. 18C is an explanatory diagram showing opening and closing of the valves 25 and 26. For comparison with FIGS. 18B and 18C, the same explanatory diagram as FIG. 16A is shown as FIG. 18A. 18B and 18C, the dotted line 31B indicates the pressure of the actuator structures 22A and 22C, the solid line 32B indicates the pressure of the actuator structures 22B and 22D, the dotted line 37B indicates opening and closing of the valve 25, and the solid line 38B indicates opening and closing of the valve 26, respectively. Show.
Note that the posture (g) is determined by the control unit 29 by, for example, the motion sensor shown in FIG. 16B indicating the characteristic motion at the start of the standing motion, such as the waist moving in the horizontal direction and then moving in the vertical direction. It can be determined by the control unit 29 by detecting from the 27 acceleration changes. Alternatively, the control unit 29 can determine by detecting the moment when force is applied to the leg by the myoelectric sensor 28. In order to accurately detect the intention of standing up at the time of posture (f), a combination of the acceleration of the motion sensor 27 and the trunk inclination angle is suitable. By combining these and determining by the control unit 29, the assist for rising can be started from the posture (f).

  The driving method of each actuator 1 at the time of standing includes a preparation step for detecting the moment when the buttocks leave the chair 103, a step for supporting the standing motion, and a step for setting the posture after standing.

  Before entering the standing-up operation, the pressure state is the same as in step S24 of FIG. 13, and the actuator structures 22B and 22D are pressurized to such an extent that they are not crushed and expand in the radial direction. 22C takes into account the force generated by the actuator structures 22B and 22D, and in the seated position, the pressure is applied so as to balance the actuator structures 22B and 22D, and the valves 25 and 26 are closed. 16A, when the control unit 29 determines that the intention to stand up is detected by the motion sensor 27, the control unit 29 opens the valve 25 and pressurizes the actuator structures 22A and 22C (see FIG. 16A). 17 step S31). And after determining with the control part 29 having detected the attitude | position (g) from which the buttocks left | separated from the chair 103, the valve | bulb 26 is opened by the control part 29 (step S32 of FIG. 17).

  After the buttocks move away from the chair 103, the pressure of the actuator structures 22A and 22C is decreased and the pressure of the actuator structures 22B and 22D is increased, thereby supporting the standing motion of extending the hip joint. After the pressures of the actuator structures 22A and 22C and the actuator structures 22B and 22D match, the pressures of the actuators 22A and 22C and the actuators 22B and 22D are reduced while maintaining the same pressure (step S33 in FIG. 17). When the actuator structures 22A and 22C and the actuator structures 22B and 22D have the same pressure, the force generated by the pressure is balanced, and only the static spring force works. When this static spring force is configured to be balanced in a standing posture, the force generated by pressure is balanced before and after posture (h), but the hip joint is bent. Support to stretch the hip joint with a strong spring force. When the assist force is insufficient with only the static spring force, the pressure of the actuators 22B and 22D may be higher than the pressure of the actuators 22A and 22C.

Then, the pressure of the actuator structures 22A and 22C and the actuator structures 22B and 22D is adjusted to support the standing-up operation, and when the standing-up operation is almost completed, a transition is made to a steady state. At this time, preload is applied to the actuator structures 22A and 22C and the actuator structures 22B and 22D, and the valve 25 and the valve 26 are closed by the control unit 29 (step S34 in FIG. 17).
As described above, the assist pants 20 according to the first embodiment can also be used for support for rising.

  The assist pants 20 of the first embodiment can also support the walking motion by independently operating the right leg and left leg actuators 1 in accordance with the walking motion.

(Embodiment 2)
The second embodiment is different from the first embodiment only in the actuator structure, piping, valve, pressure source and control method thereof arranged on the rear surface of the assist pant body 21 of the assist pant 20B. First, the configuration of the rear surface of the second embodiment will be described with reference to FIGS. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.
FIG. 20 is a perspective view of the assist pants 20B viewed from behind. In FIG. 20, left and right actuator structures 42A, 42B, 42C and 42D, 42E, 42F are arranged in series from the waist to the backs of the left and right legs, respectively, and left and right buttocks (for hips) actuator structures. 42B and 42E are connected to the left and right central valves 46 via left and right pipes 44B, respectively. The actuator structures 42A, 42D, 42C, and 42F on the left and right upper side (for the waist) and the lower side (for the back of the thigh) are connected to the left and right end side valves 45 via the left and right pipes 44A, respectively. And 46 are connected to the right and left pressure sources 43. Therefore, the actuators 1A and 1C on the front side expand and contract in the longitudinal direction by controlling the pressure of the fluid in the hollow portion of the cylindrical body 10, and the actuator structures 22A and 22C, the pressure source 23A, the piping 24 and a valve 25 are provided. The upper and lower actuators on the rear side? Is configured to expand and contract in the longitudinal direction by controlling the pressure applied to the hollow portion of the cylindrical body 10, and includes actuator structures 42A, 42D, 42C, 42F, a pressure source 43, a pipe 44A, and a valve. 45. Each actuator on the back buttock? Is configured to expand and contract in the radial direction and expand and contract in the longitudinal direction by controlling the pressure of the fluid in the hollow portion of the cylindrical body 10. The actuator structures 42 B and 42 E, the pressure source 43, and the piping 44B and a valve 46 are provided.

  Each pressure source 43 increases and decreases the pressure inside the actuator structures 42B and 42E by flowing fluid into and out of the actuator structures 42B and 42E via the valve 46 and the pipe 44B, and thereby the actuator structures 42B and 42E. 42E is expanded and contracted, and the pressure inside the actuator structures 42A, 42D, 42C, and 42F is increased and decreased by flowing fluid into and out of the actuator structures 42A, 42D, 42C, and 42F through the valve 45 and the pipe 44A. Then, the actuator structures 42A, 42D, 42C, and 42F are expanded and contracted.

  FIG. 21 shows a block diagram of control. In the second embodiment, the control unit 29 determines the operation of the user 100 based on a signal from the motion sensor 27 or the myoelectric sensor 28, and the front side valve 25 and the rear side valve 45, 46 is controlled and the pressure of the pressure source 23A for the front side and the pressure source 43 for the rear side is controlled.

  22A and 22B are explanatory diagrams of the assist direction of the actuator. FIG. 22A is an explanatory diagram of the actuator on the front side. FIG. 22B is an explanatory diagram of the actuator on the rear side. The operation of the actuator structure is shown when the human body undergoing bending and stretching operations is viewed from the left side. 22A, when the actuator structure 22A on the front side of the left leg is pressurized, the actuator structure 22A contracts and generates an assist force in the direction of bending the hip joint. In FIG. 22B, when the actuator structures 42A, 42B, 42C on the rear side of the left leg are pressurized, the actuator structures 42A, 42B, 42C contract and generate assist force in the direction of extending the hip joint. .

  Next, an operation when the assist pants 20B of the second embodiment is worn and seated and the control of the actuator will be described. Here, the actuators 1A and 1C on the front side include actuator structures 22A and 22C, a pressure source 23A, a pipe 24A, and a valve 25. The rear flange 1 actuator includes actuator structures 42B and 42E, a pressure source 43, a pipe 44B, and a valve 46. The upper and lower actuators 1 on the rear side include actuator structures 42A, 42D and 42C, 42F, a pressure source 43, a pipe 44A, and a valve 45. The pressure source 43 is also used as the upper and lower actuators 1 on the rear side, and the actuator structure to be driven can be switched or simultaneously driven by opening and closing the valves 45 and 46.

  FIG. 23 is a flowchart showing a method of driving the front actuators 1A and 1C and the rear upper and lower actuators 1 when seated. FIG. 24B is an explanatory diagram showing temporal changes in pressure applied by these actuators 1. FIG. 24C is an explanatory diagram showing opening and closing of the valves 25, 45 and 46. For comparison with FIG. 24B and FIG. 24C, the same explanatory view as FIG. 12A is shown as FIG. 24A. 24B and 24C, the dotted line 51 is the pressure of the actuator structures 22A and 22C, the solid line 52 is the pressure of the actuator structures 42B and 42E, the broken line 53 is the pressure of the actuator structures 42A and 42D and 42C and 42F, A dotted line 54 indicates opening and closing of the valve 25, a solid line 55 indicates opening and closing of the valve 46, and a broken line 56 indicates opening and closing of the valve 45, respectively. In the sitting operation, the right leg side performs the same operation as the left leg side, and the description is omitted.

  The driving method of the actuator at the time of sitting includes the step of pressurizing the actuator structure 42B, the step of supporting the sitting operation, and the step of setting the posture after sitting.

  Before entering the seating operation, the steady state is the same as in step S1 of FIG. 6, and preload is applied to the actuator structure 22A, the actuator structure 42B, and the actuator structures 42A and 42C, and the valves 25, 45, and 46 are applied. Is closed. When the control unit 29 determines that the seating intention is detected by the motion sensor 27 in the posture (b) of FIG. 24A, the valve 45 is opened to depressurize the actuator structures 42A and 42C, and the actuator structure 42A and When the pressure reduction of 42C is completed, the valve 45 is closed and the valve 46 is opened to pressurize the actuator structure 42B (step S41 in FIG. 23). Then, after sufficiently pressurizing the actuator structure 42B, the valve 46 is closed (step S42 in FIG. 23).

  Here, the reason why the actuator structure 42B is pressurized and expanded in the radial direction is to prepare for an impact at the time of sitting, and after the actuator structure 42B is pressurized and expanded in the radial direction, the valve 46 is expanded. By closing, the actuator structure 42B has a cushioning function. At this time, if only the actuator structure 42B is driven, the actuator structure 42B contracts in the longitudinal direction and a force acts in the direction of extending the hip joint, so that the sitting operation is disturbed. Therefore, in step S41, the actuator structures 42A and 42C are depressurized before the actuator structure 42B is pressurized, and the actuator structures 42A and 42C are extended in the longitudinal direction.

  In addition, the actuator structure 22A is pressurized when the seating operation is started in order to take a forward leaning posture during seating. At this time, since the actuator structures 42A, 42B, and 42C connected in series are weak in contracting force as a whole, the actuator structure 22A is balanced in a forward tilt posture by applying a relatively small pressure. It becomes a state. Here, the balanced state in the forward leaning posture means that the actuator structure 42B contracts but the actuator structures 42A, 42B, and 42C have the length extended when viewed as the total of the actuator structures 42A, 42B, and 42C. This is a state in which the structure 22A balances with the contracting force.

  In the assist pants 20B of the second embodiment, the seating operation is supported by changing the posture in which the force generated by the actuator structure 22A and the actuator structures 42B and 42A and 42C is balanced. Therefore, the assist force increases as the posture deviates from that set by the assist pants 20B.

  After the valve 46 is closed, the pressures of the actuator structure 42B and the actuator structures 42A and 42C remain substantially constant, the actuator structure 42B contracts, and the actuator structures 42A and 42C expand. Maintain state. Therefore, the control unit 29 supports the seating operation by adjusting the pressure of the actuator structure 22A. In an example of the sitting operation, as shown in FIG. 24A, from the posture (a) to immediately before the posture (c), the hip portion is projected backward and the posture is gradually forward tilted to balance. Then, while raising the body between the posture (c) and the posture (d), the buttocks fall toward the chair 103. For example, in order to support this operation, the control unit 29 performs control so that the pressure of the actuator structure 22A is gradually increased and the pressure is decreased with the posture (c) as a boundary (step S43 in FIG. 23). Note that if the posture (c) is a deep forward leaning posture, the center of gravity remains in front and the speed of the seating operation becomes slow. If the control unit 29 determines that the seating operation is too fast, the control unit 29 may increase the pressure of the actuator structure 22A to reduce the speed.

When such a control is performed by the control unit 29, the speed of the seating operation is reduced, or the actuator structure 42B of the collar portion is pressurized and expands in the radial direction to become a cushion. Can be relaxed. Thereby, it is possible to prevent the actuator structure 42B from being crushed and damaged by the impact of the seating.
In the second embodiment, since the actuator structure on the rear side is further divided, even if the actuator structure 42B is pressurized, if the actuator structures 42A and 42C are decompressed, the structure shown in FIG. 22B is obtained. Such a force to stretch the hip joint does not work. Therefore, there is no need to increase the pressure of the front actuator structure 22A, so that the driving pressure of the front actuator structure 22A can be reduced and the energy consumption can be reduced. In addition, since the pressure of actuator structures other than the actuator structure 42B can be kept low, the risk due to pressure resistance such as liquid leakage can be reduced.

  When the sitting is completed, the sitting state is maintained until the control unit 29 determines that the intention to stand is detected next. At this time, the actuator structures 42B and 42E lower the pressure set high in preparation for the impact of the seating to such an extent that the actuator structures 42B and 42E are not crushed, and the actuator structures 22A and 22C are seated. Reduce to a pressure that does not generate excessive force. This pressure of the actuator structures 22A and 22C is such a pressure that the slack due to the sitting posture is eliminated, and is slightly higher than the preload in the standing state. Further, the actuator structures 42A, 42D and 42C, 42F are kept in a state where the pressure is lowered, and the valves 45 and 46 are closed (step S44 in FIG. 23).

  Here, the pressure of the actuator structures 42A, 42D and 42C, 42F is kept low so that the actuator structures 42A to 42F connected in series do not generate extra force as a whole. is there. Accordingly, there is no need to increase the pressure of the actuator structures 22A and 22C while balancing while sitting, so that it is possible to reduce a feeling of pressure that causes the hip joint to be pulled from both the front and rear sides during sitting.

  Note that the pressure control of the actuator 1 shown in FIGS. 23 to 24C assumes a case where the operation from the posture (b) to the posture (d) is performed in a relatively short time, or fine control is not performed. ing. However, when the response speed of the actuator 1 is sufficiently faster than the seating operation and the posture during the seating operation can be grasped sequentially, as shown in FIGS. 25B and 25C, the actuator structure 42B, You may control to raise the pressure of 42E.

  If it does in this way, the freedom degree of a user's operation will improve. In the control shown in FIG. 24B and FIG. 24C, when entering the seating operation, the user 100 operates in accordance with the movement of the assist pants 20B. However, in the control shown in FIG. 25B and FIG. The assist pants have low rigidity, and the user can move freely. Therefore, it is possible to stop in the middle of the sitting operation or to shift to another operation in the middle, so that it is possible to cope with unexpected situations.

Specifically, no assist is performed until the posture (c), and the actuator structures 22A, 22C, and 42A to 42F are left in the preload state. Thereafter, the state immediately before sitting is determined by the controller 29 using the myoelectric sensor 28 or the like. First, the valve 45 is opened, the actuator structures 42A, 42D, 42C, and 42F are decompressed, and the valve 45 is closed. Next, the valves 25 and 46 are opened to pressurize the actuator structures 22A and 22C and 42B and 42E, and the valves 25 and 46 are closed.
At this time, the pressures of the actuator structures 42B and 42E are set higher in preparation for an impact at the time of sitting. On the other hand, the actuator structures 22A and 22C need to be greatly increased in pressure because the actuator structures 42A, 42B, 42C and 42D, 42E and 42F connected in series on the rear side are weak in contraction as a whole. There is no. Therefore, the pressure is set so as to eliminate the slack caused by the forward bending posture.
After the seating, the valve 46 is opened again, the pressure of the actuator structures 42B and 42E is lowered, and the valve 46 is closed.

  When the control as described above is performed by the control unit 29, the driving pressure of the actuator structures 22A and 22C is reduced, the degree of freedom of user operation is improved, and the risk due to pressure resistance performance such as liquid leakage can be further reduced. .

  Next, the operation when the assist pants 20B according to the second embodiment is worn and standing and the control of the actuator will be described.

  FIG. 26 is a flowchart showing a method of driving the actuators 1, 1A, 1C at the time of standing. FIG. 27A is an explanatory diagram showing a standing motion, where (e) is a sitting posture, (f) is a posture at the start of the standing motion, (g) is a posture when the buttocks are separated from the chair 103, (h ) Shows the posture just before standing up. FIG. 27B is an explanatory diagram showing changes in pressure applied by the actuators 1, 1A, 1C. FIG. 27C is an explanatory diagram showing opening and closing of the valves 25, 45 and 46. 27B and 27C, the dotted line 51B indicates the pressure of the actuator structure 22A, the solid line 52B indicates the pressure of the actuator structure 42B, the broken line 53B indicates the pressure of the actuator structures 42A and 42C, and the dotted line 54B. Indicates the opening and closing of the valve 25, the solid line 55B indicates the opening and closing of the valve 46, and the broken line 56B indicates the opening and closing of the valve 45.

  The driving method of the actuators 1, 1 </ b> A, 1 </ b> C at the time of standing includes a step of a preliminary operation until the user 100 leaves the buttocks from the chair 103, a step of supporting the standing operation, and a step of setting the posture after standing up I have.

  Before entering the preliminary operation, the pressure state is the same as in step S44 of FIG. 23, the actuator structures 22A and 22C are preloaded, and the actuator structures 42B and 42E are pressurized to such an extent that they are not crushed. The actuator structures 42A, 42D, 42C, and 42F are depressurized, and the valves 25, 45, and 46 are closed. 27A, when the control unit 29 determines that the intention to stand up is detected by the motion sensor 27, the control unit 29 opens the valve 25 and drives the actuator structures 22A and 22C to stand up. Support (preliminary operation) is started (step S51 in FIG. 26). Then, after the buttocks move away from the chair 103, the control unit 29 opens the valves 45 and 46 to make the actuator structures 42B and 4E and the actuator structures 42A, 42D, 42C and 42F have the same pressure (see FIG. 26). Step S52). Thereafter, the actuator structures 42A, 42D, 42B, 42E, 42C, and 42F are integrally driven by the pressure source 43.

  After the buttocks move away from the chair 103, the pressure of the actuator structures 22A and 22C is decreased, and the hip joints are extended by increasing the pressure of the actuator structures 42A, 42D, 42B, 42E, 42C, and 42F that are integrally driven. Supports standing motion. After the pressures of the actuator structure 22A and the actuator structures 42A, 42D, 42B, 42E, 42C, 42F match, the actuator structures 22A, 22C and the actuator structures 42A, 42D, The pressures of 42B, 42E, 42C, and 42F are lowered (step S53 in FIG. 26). When the actuator structures 22A, 22C and the actuator structures 42A, 42D, 42B, 42E, 42C, 42F are at the same pressure, the force generated by the pressure is balanced, and only the static spring force works. If this static spring force is configured so as to be balanced in a standing posture such as the posture (a) in FIG. 24A, the actuator structures 22A and 22C in the forward tilt posture before and after the posture (h). Since the actuator structures 42A, 42D, 42B, 42E, 42C, and 42F are stretched, the hip joint is supported. When the assist force is insufficient with only the static spring force, the pressure of the actuator structures 42A, 42D, 42B, 42E, 42C, and 42F may be higher than the pressure of the actuator structures 22A and 22C. .

  Then, the pressures of the actuator structures 22A and 22C and the actuator structures 42A, 4D, 42B, 42E, 42C, and 42F are adjusted to support the standing motion, and when the standing motion is almost completed, the state transitions to a steady state. At this time, preload is applied to the actuator structures 22A and 22C and the actuator structures 42A, 42D, 42B, 42E, 42C, and 42F, and the valves 25, 45, and 46 are closed (step S54 in FIG. 26).

  The assist pants 20B according to the second embodiment can also support the walking motion by independently operating the right leg and left leg actuators in accordance with the walking motion. At this time, the actuator structures 42A, 42D, 42B, 42E, 42C, and 42F are integrally driven.

Further, it is possible to prevent the actuator 1 from being crushed when it falls. FIG. 28 is an explanatory view showing the operation at the time of the fall, (a) is the walking posture, (b) is the posture when the balance starts to be lost, (c) is the posture in the middle of the fall, and (d) is immediately after the fall. Shows the attitude. Also in this case, the actuator structures 42B and 42E can be prevented from being crushed by controlling according to the flowchart shown in FIG. Alternatively, the actuator structures 42A, 42D, 42C, and 42F may be integrally driven with the actuator structures 42B and 42E to prevent the actuator structures 42A, 42D, 42C, and 42F from being crushed.
In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. For example, as shown in FIG. 29, actuator structures 42B and 42E are arranged only on the collar, and the upper ends of the actuator structures 42B and 42E and the waist restraining portion 21a are connected by an elastic first string-like member 110. In addition, the lower ends of the actuator structures 42B and 42E and the knee restraint portion 21b may be connected by an elastic second string-like member 111. The 1st string-like member 110 and the 2nd string-like member 111 can each be comprised with the wire which does not expand / contract.
In such a configuration, FIG. 30 shows an operation in the case where control is performed by the control unit 29 so as to increase the pressure of the actuator structures 42B and 42E immediately before sitting.
In FIG. 30, until the posture (c), the actuator structures 42B and 42E are kept in the preload (step S71 in FIG. 30D).
After that, the controller 29 determines the state immediately before sitting with the myoelectric sensor 28 or the like, and the controller 29 opens the valve 26 to pressurize the actuator structures 42B and 42E, so as to suppress the collapse in the radial direction. After the expansion, the valve 26 is closed (step S72 in FIG. 30).
After the seating, the valve 26 is opened again, the pressure of the actuator structures 42B and 42E is lowered, and the valve 26 is closed (step S73 in FIG. 30). This step S73 may be omitted.
At this time, in order to quickly increase the pressure between postures (c) and (d), the preload may be increased by one step at the time of posture (b). At this time, if the valve 26 is kept open after the preload of the actuator structures 42B and 42E is increased by one step and before the pressure is further increased immediately before the seating, the pressure is immediately increased immediately before the seating. Can do. Alternatively, a pressure vessel is disposed between the valve 26 and the pressure source 23B, the pressure of the pressure vessel is increased by the pressure source 23B with the valve 26 closed in the posture (b), and the valve 26 is opened in the posture (c). The pressure of the actuator structures 42B and 42E may be increased at a stroke.
With such a configuration, basically the same operation as in FIG. 10B can be performed, and the structure can be made simpler than in FIG. 10B. Compared with FIG. 10B, the actuator structures 42B and 42E are short, so the pressure can be increased instantaneously. Accordingly, there is an advantage that the user 100 can move freely until just before sitting, and the sitting operation is not hindered.
In addition, it can be made to show the effect which each has by combining arbitrary embodiment or modification of the said various embodiment or modification suitably. In addition, combinations of the embodiments, combinations of the examples, or combinations of the embodiments and examples are possible, and combinations of features in different embodiments or examples are also possible.

  The motion assist device according to the aspect of the present invention prevents the actuator structure disposed in the collar from expanding and collapsing in the radial direction when seated, can reduce damage and failure, and assists the seating operation. Useful for assist wear.

DESCRIPTION OF SYMBOLS 1, 1A, 1B, 1C, 1D Actuator 2, 2A, 2B Actuator structure 3 Pressure source 4 Piping 5 Fluid 10 Cylinder 10a Cylinder inner peripheral surface 10b Cylinder outer peripheral surface 11 First elastic member 11a First 1st elastic member inner peripheral surface 11b 1st elastic member outer peripheral surface 11c 1st elastic member through-hole 12 2nd elastic member 12a 2nd elastic member inner peripheral surface 12b 2nd elastic member outer periphery Surface 20, 20B Assist pants 21 Assist pants body 21a Waist restraint 21b Knee restraint 22A, 22B, 22C, 22D Actuator structure 23A, 23B Pressure source 24A, 24B Piping 25, 26 Valve 27 Motion sensor 27a Acceleration sensor 27b Angle Sensor 27c Gyro sensor 28 Myoelectric sensor 29 Control unit 30 Dotted line 31, 31B, 34, 34 , 36, 36B, 37, 37B Dotted lines 32, 32B, 33, 33B, 35, 35B, 38, 38B Solid lines 42A, 42B, 42C, 42D, 42E, 42F Actuator structure 43 Pressure source 44A, 44B Piping 45, 46 Valve 51, 51B, 54, 54B Dotted line 52, 52B, 55, 55B Solid line 53, 53B, 56, 56B Broken line 100 User 100a Waist 100b Knee 100c Buttocks 101 Motion assist device 110 First string member 111 Second string member A1 Axis of actuator structure A2 Center axis of cylinder b, b1, b2, b3, b5 Bone c, c1, c2, c3, c4 Groove d Outer diameter of cylinder p1 Spiral pitch of cylinder p2 Helical pitch of groove t _b bone thickness w _b bone width θ groove inclination α, α1, α2 pitch angle

Claims (7)

An operation assist device for assisting a user's operation,
An assist mechanism;
A control device for controlling the operation of the assist mechanism;
An input interface for acquiring information on the user's sitting motion,
The assist mechanism is
An assist wear body having a waist restraint and a knee restraint, and a first actuator;
The assist wear body is attached to at least the lower half of the user,
The waist restraining portion is fixed to the user's waist,
The knee restraint is fixed to the user's knee,
The first actuator is disposed so as to connect between the waist restraining portion and the knee restraining portion, and is located at a portion of the assist wear main body corresponding to at least a position of the buttocks of the user. The actuator further has an elastic cylinder wound spirally,
At least one of the outer peripheral surface and the inner peripheral surface of the cylindrical body is provided with a spiral groove with the axial center of the cylindrical body as a central axis,
By controlling the pressure of the fluid in the hollow part of the cylindrical body, it expands and contracts in the radial direction and expands and contracts in the longitudinal direction,
The control device is an operation assist device that supplies the fluid to the first actuator based on the information on the seating motion acquired by the input interface to control the radial expansion of the first actuator. The control device controls the pressurization of the first actuator even during a seating operation after the user is seated.
The motion assist device according to claim 1. The assist mechanism further includes a second actuator located on the front side of the assist wear body and arranged to connect between the waist restraint portion and the knee restraint portion,
The second actuator has an elastic cylindrical body wound in a spiral shape, and at least one of the outer peripheral surface and the inner peripheral surface of the cylindrical body, with the axis of the cylindrical body as a central axis, A groove is provided in a spiral shape, and expands and contracts in the longitudinal direction by controlling the pressure of the fluid in the hollow portion of the cylindrical body,
The control device controls the second actuator to pressurize the second actuator at the same timing as the first actuator, and pressurizes the second actuator so as to contract more than the first actuator.
The motion assist device according to claim 1. The first actuator comprises:
An actuator for a buttock located in a portion corresponding to the buttock of the user on the rear side of the assist wear body;
A waist actuator located in a portion corresponding to the waist of the user on the rear side of the assist wear body;
It is divided into a thigh back side actuator located in a portion corresponding to the back side of the user's thigh on the back side of the assist wear body,
The motion assist device according to claim 1. The input interface is configured to include any one of an acceleration sensor, an angle sensor, and a myoelectric sensor, and acquires information on the sitting operation based on information from the sensor.
The motion assist device according to any one of claims 1 to 4. As the input interface, after detecting a change in acceleration with an acceleration sensor, when an inclination angle equal to or greater than a threshold is detected with an angle sensor, the seating operation is acquired.
The motion assist device according to any one of claims 1 to 4. As the input interface, when an acceleration sensor detects a change in acceleration, and after detecting a trunk forward tilt angle that is greater than or equal to a threshold value with an angle sensor, the myoelectric sensor detects an electromyogram that is greater than or equal to the threshold value, To be there,
The motion assist device according to any one of claims 1 to 4.

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