JP2001170119A - Walk-assisting equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a walk-assisting equipment which when a person whose feet tend to be delayed in coming ahead employs it, advances before him, prevents a user from being in a position with a large forward tilt, and supports him so as to easily return to an erect position, and which is easy to handle and has high safety. SOLUTION: The walk-assisting equipment in which movement is controlled by force acting from a user, wherein a user detecting means is placed and assisting force which limits the advance of the walk-assisting equipment and backs it up is produced when the presence of the user outside a predetermined range is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a walking assist device, and more particularly, to a walking assist device that is controlled to move by an action force applied by a user.

[0002]

2. Description of the Related Art Conventionally, people who have difficulty walking by themselves, such as persons with walking dysfunction due to illness or injuries and elderly people with reduced leg strength, have been used to assist walking training and walking in daily life. As a walking assist means, a manual walker is known. In this method, a freely rotating wheel is provided at a lower part, and a handrail supporting a user's body is provided at an upper part. The user leans on the handrail and pushes with his / her own power to walk.

Japanese Patent Application Laid-Open No. 5-329186 discloses a moving body for assisting walking, a supporting portion for supporting the weight of a pedestrian,
There is disclosed a detector that detects a force in a direction in which a pedestrian walks, and a walking assistance device that compares a detection value from the detector with a target value to control movement of a moving body.

[0004] Further, although it is not controlled by a force applied by a user, Japanese Patent Laid-Open No. 7-313565 discloses that
2. Description of the Related Art A self-propelled walking training machine is disclosed in which a movement of a foot on which a user walks is detected by a sensor and the user moves forward only while the foot is detected by the sensor.

[0005]

The above-mentioned conventional walking assist means has a problem concerning operability as described below.

That is, the above-mentioned conventional manual walker has:
If the user pushes the device forward, it will move forward unconditionally, so if the user delays putting the legs forward, the walker will advance ahead of the user, and the user will be in a position with a large forward lean. Could be. Once the user leans forward, a forward force is likely to be applied to the walker, so that it becomes easier to lean forward. In addition, in the forward tilted posture, it becomes difficult to apply a backward force to the walker, so it is difficult to pull back the walker by itself and return to the upright posture.

[0007] Also, when the walking assist device disclosed in Japanese Patent Laid-Open No. 5-329186 is used, if the user applies a force higher than a target value, the device continues to move forward.
The user may lean forward significantly.

When the self-propelled walking training machine disclosed in Japanese Patent Application Laid-Open No. Hei 7-313565 is used, the user has to delay putting his / her legs forward, and if the feet come off the sensors, the device will not work. Stops, but since there is no means to recover from that state, the user must move the leg forward by his own power and return to the upright posture from the forward leaning state. Such an operation may be difficult for a person with a walking dysfunction.

[0009] It is an object of the present invention to prevent the walking assist device from moving forward when the user delays to extend the leg forward, thereby preventing the user from being in a greatly forwardly inclined posture, and furthermore, easily. An object of the present invention is to provide an easy-to-handle and highly safe walking assist device that assists the user to return to an upright posture.

[0010]

In order to achieve the above object, a walking assist device according to the present invention detects a base, a driving unit for moving the base, and a force acting on the base from a user. A walking force assisting device that is controlled based on the acting force detected by the acting force detecting device, comprising: a user detecting device that detects a user; When a person is detected to be outside the predetermined range, control means is provided for restricting advancement of the base.

[0011] Further, the walking assist device of the present invention comprises:
A walking unit that is provided with a driving unit that moves the base and an operating force detecting unit that detects an operating force acting on the base from a user, and that is controlled to move based on the operating force detected by the operating force detecting unit; The apparatus includes a user detecting means for detecting a user and a control means for changing a movement resistance of the base based on a distance to the user detected by the user detecting means.

Further, the walking assist device of the present invention comprises:
A walking unit that is provided with a driving unit that moves the base and an operating force detecting unit that detects an operating force acting on the base from a user, and that is controlled to move based on the operating force detected by the operating force detecting unit; In the apparatus, user detecting means for detecting a user, and when the user detecting means detects that the user is outside a predetermined range, generating an assisting force in a direction to retract the base. A control means is provided.

[0013] Further, the walking assist device of the present invention comprises:
A walking unit that is provided with a driving unit that moves the base and an operating force detecting unit that detects an operating force acting on the base from a user, and that is controlled to move based on the operating force detected by the operating force detecting unit; In the apparatus, user detecting means for detecting a user, and control means for retreating the base at a predetermined retreat speed when the user detecting means detects that the user is outside a predetermined range. Is provided.

[0014]

1A and 1B show the structure of a walking assist device according to the present invention. The walking assistance device 1 includes a base 2
A pair of left and right drive wheels 3 that support the base 2 movably on the floor surface and driven wheels 4 that can freely rotate in a direction;
It is provided on the base 2 and includes a support portion 5 for supporting a user, a pair of left and right motors 6 as drive means for driving the drive wheels 3, a speed reducer 7, and a drive belt 8. .

The walking assist device 1 has a force sensor 9 as an acting force detecting means for detecting at least a force in the front-back direction acting on the walking assist device 1 from the user via the support portion 5.
A distance sensor 10 for detecting the distance between the user and the walking assistance device 1; and a speed sensor 11 for detecting the speed of the motor.
And a setting device 12 for setting parameters for movement control
And a control device 13 for controlling the motor 6 in accordance with the outputs of the force sensor 9, the distance sensor 10, the speed sensor 11 and the parameters set by the setting device 12.

The walking assist device 1 supports a user with a support portion 5 and includes a force sensor 9, a distance sensor 10, and a speed sensor 1.
1 and the parameters set by the setting device 12, the control device 13 controls the speed or torque of the left and right motors 6 to drive the driving wheels 3,
By controlling the forward, backward and turning movements of the user, the walking of the user is assisted, and the user can walk easily and safely.

As the distance sensor 10, a non-contact sensor using light or ultrasonic waves can be used. As a simple method, a proximity sensor that detects the presence or absence of a user within a predetermined range may be used instead of the distance sensor.

Further, in order to improve the detection accuracy of the delay of the user's leg, it is desirable that the distance sensor 10 be provided below the base 3 so as to detect the user's leg. Also,
In that case, it is desirable to arrange a plurality of distance sensors in order to accurately detect the distance to the left and right legs of the user.

FIG. 2 is a block diagram showing the configuration of the control device 13. Outputs of the force sensor 9, the distance sensor 10, the speed sensor 11, and the parameters 21 set by the setting unit 12 are input to the computer 23 through the input unit 22. The computer 23 calculates the rotational speed or torque to be generated by the left and right motors 6 in accordance with the stored program, and outputs a speed or torque command value 26 to the motor controller 25 through the output unit 24. Motor controller 25
Controls the rotational speed or torque of the left and right motors 6 according to the command value 26.

FIG. 3 is a block diagram showing an example of the configuration of the control system of the walking assist device according to the present invention. Note that the control system shown below includes the control device 13 and the computer 23 shown in FIG.
It is realized by software executed inside.

The setting unit 12 is operated by the user or his caregiver to set the speed gain Kv and the return assisting force set value Fb.
0 is set to an appropriate value according to the user's physical condition.

Here, the return assisting force set value Fb0 is a value for setting an assisting force for pulling back the assisting device 1 and returning to the upright posture when the user's leg is delayed. The direction of retreat is positive. This value is generally set to about 50N to 200N.

The force sensor 9 is used by the user to assist the walking assist device 1.
, A forward force Fy applied in the forward direction is detected. The braking instruction unit 31 refers to the output of the distance sensor 10 and determines a braking rate β that is a value for controlling the braking of the walking support device 1.
Ask for. Here, the braking rate β is a value that controls the restriction of the movement of the walking assist device 1 in the forward direction, β = 0 indicates that the movement of the walking assist device 1 is not restricted, and β = 1 is the value of the forward direction. Stop moving. Also, 0 <β <1
Represents an intermediate state.

The product of the return assist force set value Fb0 and the braking rate β is defined as the return assist force Fb, and Fb is subtracted from the forward force Fy.
A corrected forward force Fy1 is obtained. Further, the corrected forward force Fy1
Is multiplied by a speed gain Kv to obtain a speed command Vr. That is, the expression is as follows.

[0025]

## EQU1 ## Fb = β × Fb0

[0026]

## EQU2 ## Fy1 = Fy-Fb

[0027]

Vr = Kv × Fy1 The braking unit 32 restricts the speed command value in the forward direction with respect to the speed command Vr according to the braking rate β, and adjusts the corrected speed command Vr.
1 is generated. The motor controller 25 controls the motor 6 so that the motor speed Vm detected by the speed sensor 11 matches the corrected speed command Vr1.

Here, the braking rate β is obtained as shown in FIG. 4 according to the distance D between the walking assist device 1 and the leg of the user.
That is, for a predetermined distance D1 and a predetermined distance D2 that is longer than the predetermined distance D1, when the user's leg is closer to D1, the braking rate β is set to 0, and the user's leg is higher than D2. If the distance is too far, β is set to 1. When the user's leg is between D1 and D2, β is set to a value between 0 and 1.

The corrected speed command Vr1 is obtained by correcting the speed command Vr as shown in FIG. 5 according to the braking rate β. When the braking rate β is 0, since the movement is not restricted, the corrected speed command Vr1 is made equal to the speed command Vr. When the braking rate β is 1, the correction speed command Vr1 is set to 0 when the speed command Vr is positive in order to limit the movement in the forward direction. The movement in the reverse direction is not restricted,
When the speed command Vr is negative, that is, when a speed command value in the reverse direction is given, the corrected speed command Vr1 is made equal to the speed command Vr. When the braking rate β is an intermediate value between 0 and 1, the corrected speed command Vr1 is set to an intermediate value between when the braking rate β is 0 and 1. That is, when expressed by an equation, the corrected speed command Vr1 is as follows.

[0030]

When Vr ≧ 0, Vr1 = (1−β) × Vr

[0031]

## EQU5 ## When Vr <0, Vr1 = Vr The operation of the control system of the present invention shown in FIG. 3 will be described below.

First, the user is standing sufficiently close to the walking assist device 1 without delay with respect to the walking assist device 1, and the distance D between the user's leg and the walking assist device 1 is determined.
Is kept shorter than the predetermined distance D1, the braking rate β becomes zero as shown in FIG.

In this case, the corrected forward force Fy1 becomes equal to the forward force Fy. Further, as shown in FIG. 5, the corrected speed command Vr1 becomes equal to the speed command Vr. Therefore, as shown in FIG. 6, the corrected speed command Vr1 is proportional to the forward force Fy.

Thus, when the user applies a forward or backward force to the walking assist device 1, the forward force Fy becomes positive or negative accordingly, and the corrected speed command Vr1 becomes positive or negative. Since the auxiliary device 1 moves forward or backward, the user can walk freely in a desired direction. Further, if the user does not apply a force in the front-rear direction to the walking assist device, the forward speed Fy becomes 0, so the corrected speed command Vr1 becomes 0, and the walking assist device 1 stops.

Since the speed gain Kv is the rate of change of the corrected speed command Vr1 with respect to the forward force Fy, the speed gain Kv corresponds to the reciprocal of the apparent resistance of the walking assist device 1 as seen from the user. Therefore, by adjusting the speed gain Kv, the apparent resistance of the walking assist device 1 can be freely adjusted.

On the other hand, when the user is behind the walking assist device and the distance D between the user's leg and the walking assist device 1 is longer than a predetermined distance D2, as shown in FIG. The braking rate β becomes 1.

In this case, the corrected forward force Fy1 is a value obtained by subtracting the return assist force set value Fb0 from the forward force Fy. Further, as shown in FIG. 5, the corrected speed command Vr1 becomes 0 when the speed command Vr is positive. Accordingly, as shown in FIG. 6, the corrected speed command Vr1 becomes zero when the forward force Fy is larger than the return assist force set value Fb0, and becomes negative when Fy is smaller than Fb0. become.

Thus, even if the walking assist device 1 is pushed forward and the forward force Fy becomes positive, the corrected speed command Vr1 does not become positive, so that the walking assist device does not move forward, and the user leans forward greatly. The posture is prevented.

If the force by which the user pushes the walking assist device 1 forward is smaller than the return assisting force Fb, the walking assist device 1 retreats. That is, even when no force in the front-rear direction is applied to the walking assist device 1, the walking assist device 1 automatically retreats. This is equivalent to assisting the user with the force of Fb0 backward. Thereby, even when the leg of the user is in a forward leaning posture with a delay, and it becomes difficult to apply a backward force to the walking assist device 1,
The user can easily pull back the walking assist device 1 backward and return to the upright posture. Note that even in this case,
If the walking assist device 1 is pushed forward with a force greater than Fb0,
Since the walking assist device 1 stops, it is safe.

When the user starts to delay from the walking assist device and the distance D between the user and the walking assist device 1 is halfway between D1 and D2, as shown in FIG. ,
It takes a value between 0 and 1 depending on the distance D.

In this case, since the return assist force Fb changes according to the braking rate β, the return assist force Fb changes according to the distance between the user and the walking assist device 1 as shown in FIG. When the user's leg is delayed, the amount of forward inclination of the user's posture changes according to the amount of delay, but the return assisting force Fb changes accordingly, as described above. The device 1 can be easily and stably pulled back.

If the forward force Fy is larger than the return assisting force Fb, the rate of change of the corrected speed command Vr1 with respect to the forward force Fy is (1−β) × Kv, as shown in FIG. The apparent resistance of a walking assist device changes according to the distance. As a result, when the user's leg is delayed, the apparent resistance of the walking assist device 1 increases accordingly, so that the walking assist device is difficult to move forward, and the user can recover the leg delay on his own. Is supported.

As described above, when the distance D between the user and the walking assist device 1 is between the predetermined distances D1 and D2, the distance D is smaller than D1 and the distance D is larger than D2. Intermediate control is performed. By providing such an intermediate state, a sudden change in the operation of the walking assist device 1 can be avoided, and the user can walk smoothly and comfortably.

The distance D1 is set to an appropriate distance so as not to hinder the user from walking normally. For example,
D1 is set to a distance that is about 30 cm to 50 cm larger than the distance between the user who stands upright during normal walking and the walking assist device. In addition, the distance D2 is set to an appropriate distance so that the walking assist device can be stopped without fail before the user assumes a posture inclined greatly forward. For example, D2 is 50 cm longer than the distance between the user and the walking assist device during an upright normal walking.
It is set to a distance that is about 80 cm or larger.

When the distance D between the walking assist device 1 and the user's leg increases, when the distance D decreases, the distances D1 and D2 are reduced, so that the braking rate β and the hysteresis characteristic for the distance D are reduced. May be given. When the hysteresis characteristic is provided in this manner, the start of the restriction of the forward movement of the walking assist device 1 is delayed, so that the unnecessary restriction of the forward movement during the normal erect walking is avoided, and the user can smoothly move. You can walk to In addition, when the user is recovering from the delay of the leg, the release of the restriction on the advance of the walking assist device is delayed, so that the safety is enhanced.

When the distance sensor 10 is provided with independent sensors for detecting the left and right legs of the user, or when a larger number of sensors are provided, the output of these sensors is reduced to one. It is desirable to select any one of the average value, the maximum value, the minimum value, etc. of the outputs of the sensors according to the physical condition of the user and use it for control.

Alternatively, one representative value may be obtained from output values of the distance to the user obtained from a plurality of sensors as described below and used for control. That is,
When the current minimum value of the plurality of sensor outputs becomes larger than the current representative value, the representative value is updated to this minimum value. Alternatively, when the current maximum value of the plurality of sensor outputs becomes smaller than the current representative value, the representative value is updated to this maximum value. In other cases, that is, when there is a current representative value between the maximum value and the minimum value of the current sensor output, the representative value maintains the current value.

By obtaining the representative values of the sensors in this manner, when the distance between the user and the walking assist device 1 is increasing, the minimum value of the distances obtained from the plurality of sensors is used for control. Therefore, when all sensors detect the user farther than a predetermined distance, control is performed to limit the forward movement of the walking assist device 1, and when the user is standing upright and performing normal walking, Unnecessary restriction of forward movement is prevented, and the user can walk smoothly. When the distance between the user and the walking assist device 1 is decreasing, the maximum value of the distance obtained from the plurality of sensors is used for control. Until it is detected within the distance, control to assist return is performed,
The user can surely return to the upright posture.

The above control method in the case where a plurality of sensors are provided as the distance sensor 10 is also applicable to the case where a proximity sensor for detecting the presence or absence of a user within a predetermined range is used as the distance sensor 10. The same applies.

In the above description, the braking rate β is determined by the distance D between the walking assist device 1 and the leg of the user. The modified braking rate β1 is obtained by modifying the braking rate β in accordance with the vertical force W applied vertically downward, and the braking of the walking assist device 1 is controlled by using the modified braking rate β1 instead of the braking rate β. Is also good.

FIG. 9 shows the relationship between the corrected braking rate β1, the braking rate β, and the vertical force W. When the vertical force W is smaller than the predetermined force W1, the modified braking rate β1 is set to 0, and when the vertical force W is larger than the predetermined force W2, the modified braking rate β1 is made equal to the braking rate β. When the vertical force W is an intermediate value between W1 and W2, the corrected braking rate is set to a value between the braking rate β and 0. Here, the predetermined forces W1 and W2 are the vertical force W applied when a normal user uses the walking assist device 1.
To a smaller value.

When a normal user uses the walking assist device 1, the user leans on the walking assist device 1 and the vertical force W increases, so that the corrected braking rate β1 becomes equal to the braking rate β. Therefore, the walking assist device 1 operates in the same manner as described above, and the user can walk freely in the upright state, and is prevented from being in a greatly inclined posture when the legs are delayed.

On the other hand, when the walking assist device 1 is not used and the user is not near the walking assist device 1, or when the assistant stands in front of or beside the walking assist device 1, the walking assist device 1 moves. In this case, since the distance sensor 10 cannot detect the user, the braking rate β may be 1; however, in this case, the vertical braking force W is close to 0, so the modified braking rate β1 It becomes 0. Therefore, it is possible to prevent the walking assist device 1 from unnecessarily retreating due to the effect of the returning assist force. In addition, the advance of the walking assist device 1 is prevented from being unnecessarily limited, and the assistant can easily move the walking assist device 1.

In the above description, the return assist force set value Fb0
Is set by the setting device 12, but Fb0 may be automatically set based on the force exerted by the user. FIG. 10 shows another setting method of the return assist force set value Fb0. The braking rate β is monitored. When the braking rate β exceeds 0, that is, when the user's leg is delayed, the output Fy of the force sensor 9 is stored in the memory 41, and a value obtained by multiplying the output Fy by the coefficient Kb is calculated. It is used as the return assist force set value Fb0.

In this way, when the user's leg is delayed while the user presses the walking assist device 1 strongly, such as when the user trips, the return assisting force Fb is automatically increased. Can easily return to the upright state. Also, when the user is walking by pushing the walking assist device 1 with a small force,
When the user's leg is delayed, the return assisting force Fb is reduced accordingly, so that the user can receive an assisting force suitable for him / herself and can return to an erect state with peace of mind.

FIG. 11 is a block diagram showing another example of the configuration of the control system of the walking assist device of the present invention.

The setting unit 12 is operated by the user or his caregiver to set the force gain Kf and the return assist force set value Fb0.
Is set to an appropriate value according to the physical condition of the user. The force sensor 9 detects a forward force Fy applied to the walking assist device 1 by the user in the forward direction. The braking instruction unit 31 refers to the output of the distance sensor 10 and obtains a braking rate β that is a value for controlling the braking of the walking support device 1. Here, the braking rate β is obtained as shown in FIG.

The product of the return assist force set value Fb0 and the braking rate β is defined as the return assist force Fb, and Fb is subtracted from the forward force Fy.
A corrected forward force Fy1 is obtained. Further, the corrected forward force Fy1
Is multiplied by a force gain Kf to obtain a torque command Fm. That is, the expression is as follows.

[0059]

Fb = β × Fb0

[0060]

## EQU7 ## Fy1 = Fy-Fb

[0061]

Fm = Kf × Fy1 The braking torque generator 51 determines a braking torque Fs for reducing the forward speed of the motor from the motor speed Vm detected by the speed sensor 11 and the braking rate β. Here, the braking torque Fs is obtained as shown in FIG.
That is, when the braking rate β is 0 and the motor speed Vm is negative or 0, the braking torque Fs is set to 0, and the braking rate β
When the motor speed Vm is positive, the braking torque Fs is made proportional to the product of the braking rate β and the motor speed Vm. When the proportionality coefficient is represented by Ks and expressed by an equation, the following is obtained.

[0062]

When Vm ≧ 0 Fs = β × Ks × Vm When Vm <0 Fs = 0 The corrected torque command Fm1 is obtained by subtracting the braking torque Fs from the torque command Fm. The motor controller 25 controls the current of the motor so that the torque of the motor matches Fm1.

Hereinafter, the operation of the control system of the present invention shown in FIG. 11 will be described.

First, the user is walking sufficiently close to the walking assist device 1 without delay with respect to the walking assist device 1, and the distance D between the user's leg and the walking assist device 1 is determined.
Is kept shorter than the predetermined distance D1, the braking rate β becomes zero as shown in FIG.

In this case, the corrected forward force Fy1 becomes equal to the forward force Fy. Further, as shown in FIG. 12, since the braking torque Fs becomes 0, the corrected motor torque command Fm
1 is proportional to the forward force Fy. Thus, when the user applies a force in the front-rear direction to the walking assist device 1, the motor generates a torque in the front-rear direction in response to the force, so that the user can freely walk in a desired direction with a small force.

On the other hand, when the user is delayed from the walking assist device and the distance D between the user's leg and the walking assist device 1 exceeds a predetermined distance D1, braking is performed as shown in FIG. Rate β
Becomes a positive value.

Here, when the motor speed Vm is positive, that is, when the walking assist device 1 is moving forward, as shown in FIG. 12, the braking torque Fs becomes positive, and the braking torque Fs is changed from the torque command Fm. Since the torque of the motor 6 is controlled by the reduced corrected torque command Fm1, a torque is generated in the direction of decreasing the speed, and the motor speed Vm decreases. As a result, the forward speed of the walking assist device 1 is reduced, so that the user is prevented from being in a greatly forwardly inclined posture.

Further, since the torque command Fm is obtained in proportion to the corrected forward force Fy1 obtained by subtracting the return assist force Fb from the forward force Fy, if the forward force Fy is smaller than Fb, the torque command Fm becomes negative. . Therefore, even if the forward force Fy is 0, that is, even if the user does not apply a force to the walking assist device 1, the torque command Fm becomes negative, and a torque is generated in a direction to retract the walking assist device 1.

Thus, even when the user's legs are delayed and the user leans forward and it becomes difficult to apply a backward force to the walking assist device, the user can easily use the walking assist device 1.
Can be pulled back to return to the upright position.
When the walking assist device 1 is retreating, that is, when the motor speed Vm is negative, the braking torque Fs becomes 0, so that the retreating operation is not hindered.

FIG. 13 is a block diagram showing still another example of the configuration of the control system of the walking assist device of the present invention.

The setting device 12 is operated by the user or his caregiver to set the speed gain Kv and the return speed set value Vb0.
Is set to an appropriate value according to the physical condition of the user.

Here, the return speed setting value Vb0 is a value for setting the speed at which the walking assist device 1 is retracted in order to return the user to the upright posture when the user's legs are delayed. The direction in which the auxiliary device 1 is retracted is positive. The return speed set value Vb0 is generally between 2 cm / s and 20 cm / s.
Set to a slow speed of about cm / s.

The force sensor 9 is provided to the walking assist device 1 from the user.
, A forward force Fy applied in the forward direction is detected. The braking instruction unit 31 refers to the output of the distance sensor 10 and determines a braking rate β that is a value for controlling the braking of the walking support device 1.
Ask for. Here, the braking rate β is obtained as shown in FIG. The speed command Vr is obtained by multiplying the forward force Fy by the gain Kv.

The selector 61 outputs a value obtained by inverting the sign of the speed command Vr and the return speed set value Vb0 (−−) according to the braking rate β.
Vb0) is selected or mixed, and the corrected speed command V
Find r1. Here, when β = 0, Vr1 is changed to Vr
And when β = 1, Vr1 is made equal to −Vb0. When β is an intermediate value, Vr1 is changed to Vr
And -Vb0 are mixed values according to β. That is,
The corrected speed command Vr1 is represented by the following equation.

[0075]

Vr1 = (1−β) × Vr−β × Vb0 The motor controller 25 controls the motor 6 so that the motor speed detected by the speed sensor 11 matches the corrected speed command Vr1.

Hereinafter, the operation of the control system of the present invention shown in FIG. 13 will be described.

First, the user is standing sufficiently close to the walking assist device 1 without delay with respect to the walking assist device 1, and the distance D between the user's leg and the walking assist device 1 is determined.
Is kept shorter than the predetermined distance D1, the braking rate β becomes zero as shown in FIG.

In this case, the corrected speed command Vr1 is equal to the speed command Vr, so that the corrected speed command Vr1 is proportional to the forward force Fy. Thus, when the user applies a forward or backward force to the walking assist device 1, the walking assist device 1 moves forward or backward accordingly, so that the user can walk freely in a desired direction.

On the other hand, when the leg of the user is behind the walking assist device 1 and the distance D between the user and the walking assist device 1 is longer than a predetermined distance D2, as shown in FIG. , The braking rate β becomes 1.

In this case, the corrected speed command Vr1 becomes a value obtained by inverting the sign of the return speed set value Vb0, so that the walking assist device 1 automatically retreats at the speed Vb0. Thus, even when the user's legs are delayed, the user does not have a large forward leaning posture, and the user leans forward and applies a backward force to the walking assist device 1. Even if it becomes difficult, the walking assist device 1 automatically retreats, so that the user can easily return to the upright posture.

Also, the leg of the user is lagging behind the walking assist device or is returning to the upright posture, and the distance D between the user and the walking assist device 1 is a predetermined distance D1.
And D2, the braking rate β takes a value between 0 and 1 as shown in FIG.

In this case, the corrected speed command Vr1 is a value obtained by mixing the speed command Vr and the value obtained by inverting the sign of the return speed set value Vb0 based on the braking rate β. When the user applies force to the walking assist device, the user can operate the walking assist device 1. Here, assuming that the user does not apply force to the walking assist device 1, the corrected speed command Vr1 is -β × V
It becomes b0, and the walking assist device retreats at the speed of β × Vb0. That is, the retreat speed of the walking assist device 1 changes according to the distance between the user and the walking assist device 1. Thereby, when the user returns to the erect posture after the legs are delayed, the retreat speed decreases as the walking assist device 1 approaches the user, so that the user can safely return to the erect posture. Can be.

[0083]

As described above, the walking assist device of the present invention controls the movement of the walking assist device 1 by detecting the distance between the walking assist device 1 and the user's leg, and the leg of the user is delayed. In this case, since the forward movement of the walking assist device 1 is restricted, when a person who may be unable to extend his / her legs forward due to a walking dysfunction uses the person, the user may have a greatly inclined forward posture. Is prevented and safety is improved.

When the user's leg is delayed, an assisting force for automatically retreating the walking assist device 1 is generated, so that the user assumes a forward leaning posture and applies a backward force to the walking assist device 1. The user can easily return to the upright posture even when it is difficult to add to the above, and the operability when the user independently uses it is improved.

As a result, since the user can walk independently and safely, the user can live independently and reduce the burden on the caregiver. In addition, the effect of walking training increases.

[Brief description of the drawings]

FIG. 1 is a side view and a top view showing the structure of one embodiment of a walking assist device according to the present invention.

FIG. 2 is a block diagram showing a configuration of an embodiment of a control device according to the present invention.

FIG. 3 is a block diagram showing a configuration of a control system of an embodiment of the walking assistance device according to the present invention.

FIG. 4 is a graph showing an example of a relationship between a distance between a user and a walking assistance device and a braking rate according to the present invention.

FIG. 5 is a graph showing one embodiment of the relationship between a speed command and a corrected speed command according to the present invention.

FIG. 6 is a graph showing one embodiment of a relationship between a forward force and a corrected speed command according to the present invention.

FIG. 7 is a graph showing one embodiment of the relationship between the distance between the user and the walking assist device according to the present invention and the return assisting force.

FIG. 8 is a graph showing one embodiment of the relationship between the distance between the user and the walking assist device and the resistance of the walking assist device according to the present invention.

FIG. 9 is a graph showing an example of a relationship between a braking rate and a corrected braking rate according to the present invention.

FIG. 10 is a block diagram showing an embodiment of a relationship between a distance between a user and a walking assistance device and an apparent resistance according to the present invention.

FIG. 11 is a block diagram showing a configuration of an embodiment of a control device according to the present invention.

FIG. 12 is a graph showing one embodiment of the relationship between speed and braking torque according to the present invention.

FIG. 13 is a block diagram showing a configuration of an embodiment of a control device according to the present invention.

[Explanation of symbols]

β: braking rate, Fy: forward force, D: distance sensor output, W
... vertical force, Vr ... speed command, Vm ... motor speed, Kv ...
Speed gain, Kf: force gain, Fb0: return force set value,
Vb0: Return speed setting value.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shizuko Hattori 502, Kandachi-cho, Tsuchiura-shi, Ibaraki Pref. Machinery Research Laboratory, Inc. Inside the Machinery Research Laboratory (72) Inventor Masakatsu Fujie 502, Kandachicho, Tsuchiura-shi, Ibaraki Pref.

Claims (1)

[Claims] 1. An apparatus comprising: a base; a drive unit for moving the base; and an operating force detecting means for detecting an operating force acting on the base from a user. In the walking assist device that is controlled based on the movement, the user detecting means for detecting the user, and when the distance from the base to the user is detected to be greater than a predetermined distance by the user detecting means, A walking assistance device, further comprising control means for restricting advancement of the base.