JP2013208290A - Walking assistance device and walking assistance program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a load imposed on a knee joint by a heavy load.SOLUTION: Fig.1 (a) shows that a wearable robot 1 stands upright. When the wearable robot stands upright, a motor 42 for a hip joint, which drives the hip joint 41, is positioned in the upper rear of a thigh connection member 26, and the length of a moment arm is set at L1. Fig.1 (b) shows that the wearable robot 1 is bent/stretched. When the wearable robot is bent/stretched, the motor 42 for the hip joint is moved to the side of a hip-joint assist actuator 18 by a slide mechanism. In one example, the mount of movement is set to be proportionate to a bending/stretching angle. Thereby, the length of the moment arm during bending is set at L3 shorter than in a conventional example.

Description

  The present invention relates to a walking support device and a walking support program, for example, to assisting a wearer's walk.

In recent years, wearable walking support devices that assist users in walking have been developed.
The walking support device assists the wearer's walking by reducing the joint moment required for walking at the hip joint, knee joint, ankle joint, and the like of the wearer with an actuator.

By the way, as described in the “walking assist device” of Patent Document 1, the knee joint assist actuator has a high torque and a low rotation speed in the stance phase, a low torque and a high rotation speed in the swing phase, and the like. High capacity is required. Therefore, in order to reduce the load on the knee joint assist actuator due to heavy objects as much as possible, it is desirable to reduce the weight below the waist as much as possible.
For example, there is a hip joint motor that drives a hip joint assist actuator, and the upper part of the upper thigh is placed on the waist to reduce the weight under the hips or to make the waist smarter. May be placed.

FIG. 5 is a diagram showing a case where the hip joint motor 42 is arranged on the upper thigh.
FIG. 5A shows a place where the wearable robot 1 stands upright, and a hip joint motor 42 of the hip joint assist actuator 17 that drives the hip joint 41 is disposed behind the upper thigh connecting member 26. .
The moment arm from the knee joint assist actuator 18 to the center of gravity of the hip joint motor 42 is L1.
The knee joint assist actuator 18 is coupled to the crus coupling member 27, and an ankle joint assist actuator 19 is formed at the other end of the crus coupling member 27.
FIG. 5B shows the wearable robot 1 bending its legs for bending and stretching. The moment arm from the knee joint assist actuator 18 to the center of gravity of the hip joint motor 42 is L2.

Thus, when the hip joint motor 42 is arranged on the upper upper thigh, the moment arm L2 becomes longer for the knee joint assist actuator 18 at the time of bending, and the capacity of the knee joint assist actuator 18 needs to be increased. was there.
In the case where the hip joint motor 42 is disposed at the waist, the moment arm of the entire center of gravity of the knee joint can be slightly shortened by tilting the upper body (it cannot be shortened in the case of the upper upper thigh), but is still applied to the knee joint assist actuator 18. The load is large.

JP 2011-142958 A

  An object of this invention is to reduce the load concerning a knee joint by a heavy article.

(1) In the invention described in claim 1, at least a heavy article that moves along the thigh between the hip joint and the knee joint, and the heavy article are placed on the side of the knee joint when the knee joint is bent. And a moving means that moves toward the hip joint when the knee joint is extended.
(2) In the invention described in claim 2, the walking support apparatus according to claim 1, wherein the heavy object is a motor that assists a joint moment generated in the hip joint.
(3) The invention according to claim 3 provides the walking support apparatus according to claim 2, wherein the moving means moves the motor in conjunction with the rotation amount of the motor.
(4) In the invention according to claim 4, the walking means comprises a moving mechanism for moving the motor by the output of the motor. Providing equipment.
(5) In the invention according to claim 5, a heavy article that moves along the thigh at least from the hip joint to the knee joint is placed on the side of the knee joint when the knee joint is bent. Provided is a walking support program for realizing a moving function of moving to the hip joint side by a computer during extension.

  ADVANTAGE OF THE INVENTION According to this invention, the load concerning a knee joint by a heavy article can be reduced by changing the position of a heavy article dynamically.

It is a figure for demonstrating the outline | summary of this Embodiment. It is the figure which showed the mounting state of the mounting type robot. It is the figure which showed the system configuration | structure of the mounting | wearing type robot. It is a figure for demonstrating the mechanism which moves the motor for hip joints. It is a figure for demonstrating a prior art example.

(1) Outline of Embodiment FIG. 1 is a diagram for explaining the outline of the present embodiment.
FIG. 1A shows the wearable robot 1 standing upright.
When standing upright, the hip joint motor 42 that constitutes the hip joint assist actuator 17 that drives the hip joint 41 is located at the upper rear of the upper thigh coupling member 26, and the length of the moment arm is L1.

FIG. 1 (b) shows the wearable robot 1 bending its legs for bending and stretching.
At the time of bending, the hip joint motor 42 moves to the knee joint assist actuator 18 side by a slide mechanism. The amount of movement is proportional to the bending angle. Thereby, the moment arm at the time of bending becomes L3 shorter than L2 of the conventional example.

  Since the moment arm is shortened in this way, the load applied to the knee joint assist actuator 18 at the time of bending and rising from the bending is reduced, and the ability required of the knee joint assist actuator 18 is reduced as compared with the conventional example. Therefore, the knee joint assist actuator 18 can be reduced in size, weight, and cost.

(2) Details of Embodiment FIG. 2 is a diagram showing a wearing state of the wearing robot 1.
The wearable robot 1 is worn on the waist and lower limbs of the wearer to assist (assist) the wearer's walking.
The wearable robot 1 includes a waist attachment part 21, an upper leg attachment part 22, a lower leg attachment part 23, a foot attachment part 24, an upper leg connection member 26, a lower leg connection member 27, a control device 2, a toe reaction force sensor 10, Force sensor 11, toe posture sensor 12, heel posture sensor 13, waist posture sensor 14, upper leg posture sensor 15, lower leg posture sensor 16, hip joint assist actuator 17, knee joint assist actuator 18, ankle joint assist actuator 19 and the like are provided. Yes. In addition, except for the waist mounting part 21, the control device 2, and the waist posture sensor 14, they are provided on both the left and right feet, and the respective detected values are output.
However, the toe reaction force sensor 10 and the heel reaction force sensor 11 may be provided with a toe grounding sensor and a heel grounding sensor instead of both sensors in the embodiment in which the detection of the reaction force is unnecessary. .

The waist mounting portion 21 is attached around the waist of the wearer and fixes the wearable robot 1.
The waist posture sensor 14 is attached to the waist attachment portion 21 and detects the posture of the waist (roll angle, yaw angle, pitch angle) with a gyroscope or the like. Also, by differentiating these angles, the angular velocity and angular acceleration of the waist can be obtained.

The control device 2 is attached to the waist mounting portion 21 and controls the operation of the wearable robot 1.
The hip joint assist actuator 17 includes a hip joint motor 42 and a mechanism (described later) that converts the driving force of the hip joint motor 42 into the rotational force of the hip joint 41.
The hip joint motor 42 is provided on the upper rear side of the upper thigh connecting member 26 and drives the upper thigh connecting member 26 connected to the waist mounting portion 21 by the hip joint 41 in the front-rear direction. As will be described in detail later, the hip joint motor 42 moves up and down along the upper thigh connection member 26 in conjunction with the movement of the upper thigh connection member 26 in the front-rear direction.

The upper thigh coupling member 26 is a rigid columnar member provided outside the upper thigh of the wearer, and is fixed to the upper thigh of the wearer by the upper thigh mounting portion 22. The upper thigh connecting member 26 is driven by the hip joint assist actuator 17 to support the movement of the upper thigh.
The outer side of the upper thigh mounting part 22 is fixed to the inner side of the upper thigh coupling member 26, and the inner side is fixed to the upper leg of the wearer.
The upper leg posture sensor 15 detects the upper leg posture (roll angle, yaw angle, pitch angle). In addition, by differentiating these angles, the angular velocity and acceleration of the upper thigh can be obtained.

The knee joint assist actuator 18 is provided at the same height as the knee joint of the wearer, and moves the lower leg connection member 27 in the front-rear direction with respect to the upper leg connection member 26 to move the lower leg of the wearer. Support.
The crus connecting member 27 is a columnar member having rigidity provided outside the crus of the wearer, and is fixed to the crus of the wearer by the crus attachment 23. The lower leg connecting member 27 is driven by the knee joint assist actuator 18 to support the movement of the lower leg.

The outer side of the lower leg mounting portion 23 is fixed to the inner side of the lower leg connecting member 27, and the inner side is fixed to the lower leg of the wearer.
The lower leg posture sensor 16 detects the lower leg posture (roll angle, yaw angle, pitch angle). Also, by differentiating these angles, the angular velocity and angular acceleration of the lower leg can be obtained.

The ankle joint assist actuator 19 is provided at the same height as the wearer's ankle joint, and drives the toe of the foot mounting portion 24 in the direction of moving up and down with respect to the crus coupling member 27.
The foot mounting portion 24 is fixed to the foot portion (instep and sole) of the wearer. Generally, the joint at the base of the toe is bent during walking, but the foot mounting portion 24 is also configured so that the base of the toe is bent according to the toes.

  The toe posture sensor 12 and the heel posture sensor 13 are respectively installed at the front end and the rear end of the foot mounting portion 24 and detect the toe and heel postures (roll angle, yaw angle, pitch angle), respectively. Further, by differentiating these angles, the angular velocity and angular acceleration of the toes and the heel can be obtained.

The toe reaction force sensor 10 is installed in front of the sole portion of the foot mounting portion 24 and detects the ground contact of the toe and the reaction force from the walking surface.
The heel reaction force sensor 11 is installed on the rear side of the sole of the foot mounting portion 24 and detects the ground contact of the heel and also detects the reaction force from the walking surface.
The wearable robot 1 configured as described above supports the walking of the wearer by driving the hip joint assist actuator 17, the knee joint assist actuator 18, and the ankle joint assist actuator 19.

FIG. 3 is a diagram showing a system configuration of the wearable robot 1.
The control device 2 includes an electronic control unit including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a clock as means for measuring time, a storage unit 7, various interfaces, and the like. And each part of the wearable robot 1 is electronically controlled.

The control device 2 is also configured by executing various programs such as a walking support program stored in the storage unit 7 by the CPU, and includes a sensor information acquisition unit 3, various parameter calculation units 4, a walking motion determination unit 5, A walking assist force determination unit 8 is provided.
The sensor information acquisition unit 3 acquires a detection value from each of the toe reaction force sensor 10 to the crus posture sensor 16. The detection value of each sensor acquired by the sensor information acquisition unit 3 is used for determination of walking motion, determination of a walking scene, calculation of walking parameters, and the like.

The various parameter calculation unit 4 obtains the angle, angular velocity, position, and the like of each joint from the detection value acquired by the sensor information acquisition unit 3.
The walking motion determination unit 5 determines whether the wearer's motion is a motion other than walking such as a bending / stretching motion or a stepping motion, or an actual walking motion.

  The walking assist force determining unit 8 determines the assist force to be output to the hip joint assist actuator 17, the knee joint assist actuator 18, and the ankle joint assist actuator 19 disposed on the left and right feet, and drives these assist actuators accordingly. . The assist force is a moment (torque) that the wearable robot 1 drives the assist actuator to act on the legs.

Each drawing in FIG. 4 is a diagram for explaining a mechanism for moving the hip joint motor 42.
FIG. 4A is a view showing the upper thigh coupling member 26 and the hip joint assist actuator 17 when the wearable robot 1 is standing upright.
Among these, the bevel gear 33, the rotation shaft 32, the bevel gear 31, and the hip joint motor 42 constitute the hip joint assist actuator 17, and the worm gear 34, the rotation shaft 32, and the rack 35 constitute a movement mechanism for the hip joint motor 42. Yes. Thus, the rotating shaft 32 operates both the hip joint assist actuator 17 and the moving mechanism.

Around the hip joint 41, a bevel gear (bevel gear) 33 fixed to the upper thigh connecting member 26 (that is, rotating with the upper thigh connecting member 26) is formed.
The hip joint motor 42 can move by sliding in the longitudinal direction behind the upper thigh coupling member 26 along a track defined by a guide (guide mechanism) (not shown).

  The hip joint motor 42 is composed of, for example, a DC motor, and is arranged so that the longitudinal direction of the upper thigh coupling member 26 and the rotation shaft 32 are parallel to each other. The rotating shaft 32 has a degree of freedom of rotation with respect to the hip joint motor 42 and has no degree of freedom in the axial direction. Therefore, both the hip joint motor 42 and the rotating shaft 32 move in the longitudinal direction of the upper thigh coupling member 26.

A bevel gear 31 that meshes with the bevel gear 33 is installed on the upper side of the rotation shaft 32 (on the side of the hip joint 41 in the longitudinal direction of the upper thigh connecting member 26).
The rotating shaft 32 can move in the axial direction on the central axis of the bevel gear 31 but is fixed in the rotating direction. That is, when the rotating shaft 32 rotates, the bevel gear 31 rotates along with this, and slides up and down with respect to the rotating shaft 32.

Further, the position of the bevel gear 31 with respect to the hip joint 41 is fixed at a position where the bevel gear 33 and the bevel gear 31 mesh with each other by a fixing mechanism (not shown).
By the bevel gear 31 and the bevel gear 33, the rotational force of the hip joint motor 42 is transmitted to the hip joint 41, and the assist force is exhibited.
On the other hand, a worm gear 34 is fixed to the other end side of the rotating shaft 32.

A rack 35 that meshes with the worm gear 34 is fixed in the longitudinal direction of the upper thigh connection member 26 at the lower rear of the upper thigh connection member 26.
Since the worm gear 34 and the rack 35 are engaged with each other in this way, when the rotary shaft 32 rotates, a force for moving the hip joint motor 42 in the longitudinal direction of the upper thigh coupling member 26 is generated by the worm gear 34.

In the present embodiment, when the rotation direction of the rotation shaft 32 rotates the upper thigh coupling member 26 forward (when the wearer bends the leg), the hip joint motor 42 is used for the knee joint assist actuator 18. The thread of the worm gear 34 is formed so as to move in the direction.
For this reason, when the wearer bends to bend and stretch, the hip joint motor 42 moves in the direction of the knee joint assist actuator 18 in proportion to the movement, and when the wearer stands up, the hip motor 42 in proportion to the movement. Moves in the direction of the hip joint 41.

FIG. 4B shows the wearer bending the leg for bending and stretching. In addition, the wavy line has shown the state when it was standing upright, ie, before bending.
As shown by the arrow 51 in the figure, when the upper leg connecting member 26 is moved and the leg is bent, the hip joint motor 42 moves in the direction of the knee joint assist actuator 18 as shown by the arrow 52. .

Thereby, the moment arm of the hip joint motor 42 with respect to the knee joint assist actuator 18 can be shortened.
As described above, the hip joint motor 42 moves in the direction of the knee joint assist actuator 18 when bending the leg, and moves in the direction of the hip joint 41 when extending the leg.

  In the hip joint assist actuator 17, the hip joint motor 42 moves to the knee side even when the thigh is raised instead of bending and stretching. In this case, the load on the hip joint assist actuator 17 is increased. It is easier than the joint assist actuator 18.

FIG.4 (c) is a figure for demonstrating a modification.
In addition to the combination of the bevel gear 33 and the bevel gear 31, a combination of the pinion gear 37 and the crown gear 36 can also be used. Other mechanisms may be used.

In the present embodiment described above, the hip joint motor 42 is moved by a mechanical mechanism. However, an actuator that moves the hip joint motor 42 is installed and controlled to move the hip joint motor 42. It can also be configured.
In this case, for example, the hip motor 42 is moved at the time of bending due to bending and stretching, and the hip motor 42 is not moved at the time of bending such as raising the thigh (the load on the hip joint motor 42 can be reduced). It can be determined and controlled.

Further, in the present embodiment, the hip joint motor 42 is disposed behind the upper thigh coupling member 26, but may be disposed on the side surface or the front side.
Furthermore, in the present embodiment, the hip joint motor 42 is moved as a heavy object, but other heavy objects such as a battery may be moved.

According to the embodiment described above, the following effects can be obtained.
(1) By having a structure in which the hip joint motor 42, which is a heavy object, is brought close to the knee joint assist actuator 18 when the hip joint is bent, the moment at the knee joint of the hip joint motor 42 can be reduced. The load on the motor that drives the motor can be reduced.
(2) By adopting a structure using a single actuator for sliding the hip joint motor 42 (the hip joint motor 42 performs both rotation of the hip joint 41 and slide of the hip joint motor 42 by a single operation. This saves space, reduces weight, and saves energy.

According to the embodiment described above, the following configuration can be obtained.
(1) Since the hip joint motor 42 corresponds to a heavy object and moves along the upper thigh coupling member 26, the wearable robot 1 (walking support device) is placed on the thigh between the hip joint and the knee joint. It is equipped with heavy objects that move along.
The hip joint motor 42 moves to the knee joint side when the knee joint is bent and moves to the hip joint side when the knee joint is extended by the moving mechanism using the worm gear 34 and the rack 35. And a moving means that moves toward the knee joint when the knee joint is bent and moves toward the hip joint when the knee joint is extended.
(2) Since the hip joint motor 42 is an electric motor that exerts an assist force by the hip joint assist actuator 17, the heavy object is a motor that assists a joint moment generated at the hip joint.
(3) Since the hip joint motor 42 moves according to the rotation amount of the rotary shaft 32 by the moving mechanism, the moving means moves the motor in conjunction with the rotation amount of the motor.
(4) Since the hip joint motor 42 is moved by its own rotational force, the moving means includes a moving mechanism for moving the motor by the output of the motor.

DESCRIPTION OF SYMBOLS 1 Wearable robot 2 Control apparatus 3 Sensor information acquisition part 4 Various parameter calculation part 5 Walking motion determination part 7 Memory | storage part 8 Walking assist force determination part 10 Toe reaction force sensor 11 踵 Reaction force sensor 12 Toe attitude sensor 13 踵 Posture sensor 14 Waist posture sensor 15 Upper leg posture sensor 16 Lower leg posture sensor 17 Hip joint assist actuator 18 Knee joint assist actuator 19 Ankle joint assist actuator 21 Lumbar attachment part 22 Upper leg attachment part 23 Lower leg attachment part 24 Foot attachment part 26 Upper leg connection member 27 Lower leg Connecting member 31 Bevel gear 32 Rotating shaft 33 Bevel gear 34 Worm gear 35 Rack 36 Crown gear 37 Pinion gear 41 Hip joint 42 Hip motor 51, 52 Arrow line

Claims (5)

A heavy object that moves along the thigh between at least the hip joint and the knee joint;
Moving means for moving the heavy object to the knee joint side when the knee joint is bent, and to the hip joint side when the knee joint is extended;
A walking support device characterized by comprising:   The walking support apparatus according to claim 1, wherein the heavy object is a motor that assists a joint moment generated at the hip joint.   The walking support apparatus according to claim 2, wherein the moving unit moves the motor in conjunction with an amount of rotation of the motor.   The walking support device according to claim 2, wherein the moving unit includes a moving mechanism that moves the motor according to the output of the motor.   A function of moving a heavy object that moves along the thigh between at least the hip joint and the knee joint to the knee joint when the knee joint is bent and to the hip joint when the knee joint is extended. A walking support program realized on a computer.

Images