JP7083593B2 - Braking method for electric vehicles and electric vehicles - Google Patents

Description

The present invention relates to an electric vehicle and a braking method for the electric vehicle for assisting the walking of an elderly person, a physically handicapped person, an inpatient or a person having limited walking.

Conventionally, a walker (silver car, wheelbarrow) that assists the elderly to go out, a walker or other walking assist device has been used to assist the walking of a physically handicapped person or an inpatient. For example, Patent Document 1 discloses a walking assist device capable of performing a straight-ahead / turning motion with a simple operation.

In the walking assist device (electric wheelbarrow) of Patent Document 1, a frame body having a handle portion gripped by a pedestrian, a plurality of wheels provided on both left and right sides of the frame body, and a plurality of wheels for rotationally driving each wheel. It includes a drive motor and a control means that detects the counter electromotive force generated in the drive motor and controls the drive motor based on the counter electromotive force.

Further, in the walking assist device of Patent Document 1, a grip sensor (touch sensor) for detecting whether or not a pedestrian is holding the handle portion is provided on the handle portion. When it is determined that the pedestrian is not holding the steering wheel based on the detection signal of the grip sensor, each wheel is controlled to be braked. However, in such a conventional walking assist device, it is necessary to determine whether or not a pedestrian is holding the steering wheel portion by using a grip sensor. Therefore, the cost of the walking assist device may increase by providing the grip sensor on the handle portion.

Japanese Unexamined Patent Publication No. 2009-183407

An object of the present invention is to provide an electric vehicle and a braking method for the electric vehicle, which can determine whether or not a pedestrian is operating the electric vehicle without using a grip sensor or the like.

The electric vehicle according to the present invention is an electric vehicle provided with wheels or an endless track, and a user can use the electric vehicle based on a change in the acceleration of the wheel or the endless track and a braking unit for braking the wheel or the endless track. It is characterized by including a control unit that determines whether or not the vehicle is being operated and controls the braking unit. Here, "operating" means that a part of the user's body or belongings leans when the user is pushing or pulling by hand, or when the user is holding by hand. Includes cases where it is hung, supported, or in contact. Further, "grasping" means being held in a wrapping shape, and includes not only a case where it is firmly held but also a case where it is lightly held.

In the electric vehicle according to the present invention, the control unit may determine that the user is not operating the electric vehicle when the amount of change in the acceleration is smaller than a predetermined threshold value.

In the electric vehicle according to the present invention, when the acceleration exceeds a predetermined upper limit value, the control unit may consider that the acceleration is equal to this upper limit value.

In the electric vehicle according to the present invention, the control unit receives the acceleration when it is smaller than a predetermined positive threshold value or when the acceleration is larger than a predetermined negative threshold value, whichever is the case. It may be determined that the user is not operating the electric vehicle.

In the electric vehicle according to the present invention, the control unit may control the braking unit to brake the wheels or the endless track when it is determined that the user is not operating the electric vehicle.

In the electric vehicle according to the present invention, the control unit of the wheel or the endless track of the wheel or the endless track while the acceleration of the electric vehicle is zero or a negative value after starting braking of the wheel or the endless track. Braking may be continued.

The electric vehicle according to the present invention further includes a speed detection sensor that detects the rotational speed of the wheel or the endless track, and the control unit calculates the acceleration of the electric vehicle based on the signal from the speed detection sensor. You may.

The electric vehicle according to the present invention further includes an inclination detection sensor for detecting the inclination of the electric vehicle, and the control unit determines that the electric vehicle is located on an ascending inclined surface by the inclination detection sensor, and the wheels or When the endless track is rotating backward, it may be determined that the user is not operating the electric vehicle.

The electric vehicle according to the present invention is further provided with an inclination detection sensor for detecting the inclination of the electric vehicle, the wheels or the endless tracks are provided in pairs on the left and right, and the control unit is such that the electric vehicle is left and right by the inclination detection sensor. The wheel or the endless track, which is determined to be located on an inclined surface and is located on one of the upper side and the lower side of the inclined surface, is stationary or rotates forward, and is above and below the inclined surface. When the wheel or the endless track located on the other side is stationary or rotating backward, it may be determined that the user is not operating the electric vehicle.

The electric vehicle according to the present invention is an electric vehicle provided with wheels or an endless track, and is provided with a braking unit for braking the wheels or the endless track, an inclination detection sensor for detecting the inclination of the electric vehicle, and the inclination detection sensor. When it is determined that the electric vehicle is located on an ascending inclined surface and the wheel or the endless track is rotating backward, it is determined that the user is not operating the electric vehicle and the braking is performed. It is characterized by having a control unit for controlling the unit.

The electric vehicle according to the present invention is an electric vehicle provided with wheels or an endless track, and is provided with a braking unit for braking the wheels or the endless track, an inclination detection sensor for detecting the inclination of the electric vehicle, and the inclination detection sensor. It is determined that the electric vehicle is located on an inclined surface inclined to the left and right, and the wheel or the endless track located on one of the upper side and the lower side of the inclined surface is stationary or rotates forward, and the inclined surface. When the wheel or the endless track located on the other of the upper side and the lower side of the vehicle is stationary or rotating backward, it is determined that the user is not operating the electric vehicle and the control unit controls the braking unit. It is characterized by having.

The braking method of an electric vehicle according to the present invention is a braking method of an electric vehicle provided with wheels or an endless track, and it is determined whether or not the user is operating the electric vehicle based on a change in acceleration of the electric vehicle. It is characterized in that it determines and brakes the wheel or the endless track.

The braking method of an electric vehicle according to the present invention is a braking method of an electric vehicle provided with wheels or an endless track, in which the electric vehicle is located on an ascending inclined surface and the wheels or the endless track are rotated rearward. If so, it is determined that the user is not operating the electric vehicle, and the wheel or the endless track is braked.

The braking method of an electric vehicle according to the present invention is a braking method of an electric vehicle provided with a pair of left and right wheels or an infinite track, in which the electric vehicle is located on an inclined surface inclined to the left and right, and above and below the inclined surface. When the wheel or infinite track located on one of the wheels or infinite track is stationary or rotating forward, and the wheel or infinite track located on the other of the upper and lower sides of the inclined surface is stationary or rotating backward, the user. Is characterized in that it determines that the electric vehicle is not operating and brakes the wheel or the infinite track.

According to the present invention, it is possible to determine whether or not a pedestrian is operating an electric vehicle without using a grip sensor or the like.

FIG. 1 is a perspective view showing an electrically assisted walking vehicle according to an embodiment of the present invention. FIG. 2 is a flowchart illustrating an example of a control method for an electrically power assisted walking vehicle according to an embodiment of the present invention. FIG. 3 is a graph showing the measured value of the rotational acceleration of the rear wheels and the low frequency component of the rotational acceleration of the rear wheels. FIG. 4 is a flowchart illustrating a modification 1 of the control method of the electrically power assisted walking vehicle. FIG. 5 is a schematic view showing an electrically assisted walking vehicle located on an ascending inclined surface. FIG. 6 is a flowchart illustrating a modification 2 of the control method of the electrically power assisted walking vehicle. FIG. 7 is a schematic view showing an electrically assisted walking vehicle located on an inclined surface inclined to the left and right.

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3. In the following description, the same configurations are designated by the same reference numerals. Their names and functions are the same. Therefore, the detailed description of them will not be repeated.

FIG. 1 is a diagram showing an electric walking vehicle (hereinafter referred to as an electrically assisted walking vehicle) as an example of an electric vehicle. FIG. 1 is a schematic perspective view showing an example of the appearance of the electrically power assisted walking vehicle 10 according to the present embodiment.

(Composition of electrically power assisted walking vehicle)
As shown in FIG. 1, the electrically power assisted walking vehicle 10 includes a frame 11, a pair of front wheels 12 and a pair of rear wheels (wheels) 13 provided on the frame 11, and a pair of handles 14 connected to the frame 11. It is equipped with.

Motors 20 that assist the movement of the corresponding rear wheels 13 are connected to the pair of rear wheels 13. A battery 21 and a control unit 16 are attached to the frame 11. Further, the control unit 16 is provided with a speed detection sensor (detection unit) 22 and a tilt detection sensor 23.

Next, each component of the electrically power assisted walking vehicle 10 will be further described.

The frame 11 has a pair of left and right pipe frames 31. A pair of front wheels 12 are provided on the front end side of each of the pair of left and right pipe frames 31. Each of the pair of front wheels 12 is rotatable in the front-rear direction and is also rotatably provided around a vertical axis. In this case, the pair of front wheels 12 are free wheels that can freely change direction.

Further, a pair of rear wheels 13 are provided on the rear end side of each of the pair of left and right pipe frames 31. Each rear wheel 13 is provided so as to be rotatable in the front-rear direction. As a result, the electrically assisted walking vehicle 10 can be easily moved forward and backward, and can be easily moved or turned in the left-right direction.

A pair of handles 14 operated by the user are provided at the upper ends of the pair of left and right pipe frames 31. In the present embodiment, a case where the pair of handles 14 are gripped by a user's hand will be described as an example. The pair of handles 14 are connected to each other by a bar handle 17 extending in the horizontal direction. Further, the pair of handles 14 and the bar handles 17 have a substantially U-shape. Further, a horseshoe-shaped portion 27 on which the user's elbow can be placed is attached to the pair of handles 14. The horseshoe-shaped portion 27 is provided with a hole so that each handle 14 can be inserted, and the handle 14 can be attached to the hole. The configuration of the handle 14 is not limited to this, and for example, a pair of left and right pipe frames 31 may be provided with independent handles 14.

In the present embodiment, the electrically assisted walking vehicle 10 is not provided with a grip sensor, a strain sensor, a proximity sensor, a pressure sensor, or the like that directly detects whether or not the user has grasped the pair of handles 14. ..

A seat portion 37 on which the user can sit is provided between the pair of left and right pipe frames 31 as needed.

The battery 21 supplies electric power to each element of the electrically power assisted walking vehicle 10, such as the motor 20 and the control unit 16. The battery 21 is provided below the seat portion 37 located between the pair of pipe frames 31.

In the present embodiment, the motor 20 is attached to the inside of each rear wheel 13. As the motor 20, any motor such as a servo motor, a stepping motor, an AC motor, or a DC motor can be used, and a speed reducer integrally formed may be used.

In the present embodiment, the motor 20 not only assists the operation of the rear wheels 13 but also has a function as a dynamic brake. That is, in the present embodiment, the motor 20 serves both as a driving unit for driving the rear wheels 13 and as a braking unit for braking the rear wheels 13. When the motor 20 brakes the rear wheels 13, the motor 20 works as a generator and its resistance is used as a brake. When the motor 20 serves as a braking unit, it may be used as a reverse brake for driving the motor 20 in the opposite direction or as a short-circuit brake for short-circuiting the phases of the motor 20. Alternatively, the motor 20 may only serve as a drive unit for driving the rear wheels 13, and the braking unit for braking the rear wheels 13 may be provided separately from the motor 20. Examples of such a braking unit include an electromagnetic brake, a mechanical brake, and the like.

In the present embodiment, the motor 20 is attached to each rear wheel 13, but the present invention is not limited to this, and the motor 20 may be attached only to the pair of front wheels 12, or the motor 20 may be attached to the pair of front wheels 12 and the pair. It may be attached to all of the rear wheels 13.

The control unit 16 controls the entire electrically assisted walking vehicle 10 such as the motor 20. In this case, the control unit 16 is provided in the vicinity of the battery 21. The details of the control by the control unit 16 will be described later.

The speed detection sensor (detection unit) 22 detects the rotation speed or rotation speed of the rear wheel 13, and transmits a signal of this rotation speed or rotation speed to the control unit 16. In this case, the control unit 16 calculates the rotational acceleration of the rear wheel 13 by differentiating the rotational speed of the rear wheel 13 based on the signal from the speed detection sensor 22. The speed detection sensor 22 may be built in the pair of rear wheels 13 of the electrically power assisted walking vehicle 10. Alternatively, the speed detection sensor 22 may be incorporated only inside the pair of front wheels 12 or may be incorporated in all of the pair of front wheels 12 and the pair of rear wheels 13, similarly to the motor 20.

When the motor 20 is a brushless motor, the speed detection sensor 22 may calculate the rotation speed or speed of the wheels and the speed of the electrically assisted pedestrian vehicle 10 by using the Hall element built in the motor 20. ..

If the speed can be detected from the counter electromotive force of the motor 20, the rotation speed or speed of the wheels and the speed of the electrically assisted walking vehicle 10 are calculated from the counter electromotive force, and each rear wheel is configured. When the angular velocity of 13 or each front wheel 12 can be detected, it can be configured to calculate the rotation speed or speed of the wheels and the speed of the electrically assisted walking vehicle 10 from this angular velocity.

Further, the speed detection sensor 22 is not limited to being built in the pair of front wheels 12 and / or the pair of rear wheels 13, and may be attached to any other member such as the frame 11 and the pair of handles 14. Alternatively, the speed detection sensor 22 may be arranged in the vicinity of the control unit 16.

Alternatively, the detection unit may be composed of an acceleration detection sensor. In this case, the acceleration detection sensor directly detects the acceleration of the electrically power assisted walking vehicle 10 without using the rotational acceleration of the rear wheels 13, and transmits a signal of this acceleration to the control unit 16. Further, the control unit 16 is configured to calculate the speed by integrating the acceleration.

Further, the detection unit may be configured by GPS (Global Positioning System). In this case, the GPS detects the position of the electrically power assisted walking vehicle 10 without using the rotational acceleration of the rear wheels 13. Further, the control unit 16 may be configured to calculate the speed of the electrically power assisted walking vehicle 10 by differentiating the position information from the GPS, and calculate the acceleration by differentiating the position information from the GPS twice. can.

The tilt detection sensor 23 detects the tilt of the electrically assisted walking vehicle 10, for example, whether the electrically assisted walking vehicle 10 is on a flat surface or an inclined surface, and the front-back direction and / or the left-right direction of the electrically assisted walking vehicle 10. A signal regarding the inclination to is transmitted to the control unit 16. In this case, the tilt detection sensor comprises two or more axes of acceleration detection sensors. The tilt detection sensor 23 is provided in the vicinity of the control unit 16. Alternatively, the tilt detection sensor 23 may be provided on the upper part of the electrically assisted walking vehicle 10. Instead of using the acceleration detection sensor as the tilt detection sensor 23, the posture of the electrically assisted walking vehicle 10 may be detected by using a gyro sensor.

In the present embodiment, the control unit 16 determines whether or not the user is operating the steering wheel 14 or the like of the electrically assisted walking vehicle 10 based on the change in the acceleration of the electrically assisted walking vehicle 10. Then, when it is determined that the user does not operate the electrically assisted walking vehicle 10 and has released his / her hands from the steering wheel 14 (both hands are released), the control unit 16 controls the motor 20 (braking unit) to control the rear wheels. Braking 13 is performed. In the following, the control unit 16 calculates the rotational acceleration of the rear wheels 13 based on the signal sent from the speed detection sensor 22, and the user uses the electrically assisted walking vehicle 10 based on the change in the rotational acceleration. The case of determining whether or not the operation is performed will be described as an example.

(Control method by control unit)
Next, a method of controlling the electrically assisted walking vehicle 10 by the control unit 16 will be described. FIG. 2 is a flowchart for explaining an example of the operation of the control unit 16.

First, it is assumed that the control unit 16 implements the assist control mode (step S11 in FIG. 2). In this case, the rotation of the rear wheel 13 of the electrically assisted walking vehicle 10 is assisted by the motor 20, and the motor 20 is driven so as to generate a force that is insufficient only by the user's operating force.

Subsequently, the control unit 16 determines whether or not the user is operating the handle 14 or the like of the electrically assisted walking vehicle 10 (step S12 in FIG. 2).

Specifically, the control unit 16 calculates the rotational acceleration of the rear wheel 13 by differentiating the rotational speed based on the rotational speed signal from the speed detection sensor 22. The calculated rotational acceleration is an actually measured value of the rotational acceleration of the rear wheel 13, and corresponds to the instantaneous acceleration before signal processing. In FIG. 3, the solid line shows the change in the rotational acceleration of the rear wheel 13 calculated in this way.

Subsequently, the control unit 16 processes the calculated rotational acceleration signal of the rear wheel 13 through a low-pass filter, and extracts only the low frequency component from the rotational acceleration signal. This extracted low frequency component corresponds to an average or time series change in the rotational acceleration of the rear wheel 13. In FIG. 3, the broken line indicates the low frequency component of the rotational acceleration of the rear wheel 13 thus obtained. The control unit 16 may perform signal processing by obtaining a moving average using the signal of the rotational acceleration of the rear wheel 13. In this case, the low frequency component of the rotational acceleration of the rear wheel 13 may be calculated from the moving average of the measured values of the rotational acceleration.

Next, the control unit 16 calculates the squared average of the difference between the measured value of the rotational acceleration (instantaneous acceleration, solid line in FIG. 3) and the low frequency component (average or time-series acceleration, broken line in FIG. 3). , Calculated as the high frequency component (vibration component) of the rotational acceleration. In FIG. 3, the area of the region shown by the diagonal line indicates the difference between the measured value of the rotational acceleration and the low frequency component (value of the high frequency component before squared). The value of the high frequency component of the rotational acceleration may be obtained as the absolute value of the difference between the measured value of the rotational acceleration and the low frequency component.

Here, in general, when the user is operating the steering wheel 14 or the like of the electrically assisted walking vehicle 10, the rotational acceleration of the rear wheels 13 tends to change (increase / decrease) instantaneously according to the walking of the user. Therefore, when the user is operating the electrically assisted walking vehicle 10, the measured value of the rotational acceleration (solid line in FIG. 3) tends to deviate from the low frequency component of the rotational acceleration (broken line in FIG. 3).

On the other hand, when the user releases the handle 14 or the like of the electrically assisted walking vehicle 10 and the electrically assisted walking vehicle 10 is freely falling on an inclined surface or the like, the rotational acceleration of the rear wheels 13 is substantially constant. Becomes the value of. Therefore, when the user releases the electrically assisted walking vehicle 10, the measured value of the rotational acceleration (solid line in FIG. 3) tends to approach the low frequency component of the rotational acceleration (broken line in FIG. 3). Therefore, it is possible to determine whether or not the user has released his / her hand from the electrically assisted walking vehicle 10 by determining how much the measured value of the rotational acceleration deviates from the low frequency component of the rotational acceleration.

Specifically, as described above, the control unit 16 obtains the root mean square of the difference between the measured value of the rotational acceleration and the low frequency component as the high frequency component, and the value of the high frequency component per unit time is larger than a predetermined threshold value. Judge whether or not. Then, when the value of the high frequency component is smaller than the predetermined threshold value, the control unit 16 determines that the user does not operate the electrically assisted walking vehicle 10 and has released his hand from the steering wheel 14. In this case, the control unit 16 controls the motor (braking unit) 20 to cause the motor 20 to function as, for example, a dynamic brake, and brakes the rear wheels 13 (step S13 in FIG. 2). This makes it possible to prevent the electrically assisted walking vehicle 10 from unintentionally moving when the user is not operating the electrically assisted walking vehicle 10.

On the other hand, in the control unit 16, when the value of the high frequency component per unit time is larger than a predetermined threshold value, the user is operating the electrically assisted walking vehicle 10, and the user walks while grasping the handle 14. Judge that there is. In this case, the control unit 16 continues to assist the movement of the rear wheels 13 by the motor 20 without braking the rear wheels 13.

The control unit 16 repeats the above process until the main power of the electrically power assisted walking vehicle 10 is turned off. In this way, the control unit 16 can determine whether or not the user is operating the electrically power assisted walking vehicle 10.

In addition to the above, the control unit 16 may optionally perform the following control.

(1) When the tilt detection sensor 23 detects that the electrically power assisted walking vehicle 10 is on a descending slope and the value of the high frequency component of the rotational acceleration of the rear wheels 13 is smaller than a predetermined threshold value, the user descends. It is determined that the hand is released from the handle 14 or the like of the electrically power assisted walking vehicle 10 on the slope of. In this case, as described above, the control unit 16 brakes the rear wheels 13, but the rotational acceleration of the rear wheels 13 suddenly changes at the moment when the rear wheels 13 are braked, so that it is conceivable that the high frequency component momentarily increases. .. In this case, the control unit 16 may erroneously determine that the user has operated the electrically power assisted walking vehicle 10. Therefore, after starting the braking of the rear wheels 13, the control unit 16 continues to use the rear wheels regardless of the value of the high frequency component while the measured value of the rotational acceleration of the rear wheels 13 is zero or a negative value. The braking of 13 may be continued.

(2) When the signal of the rotational acceleration of the rear wheel 13 is processed through a low-pass filter, if the measured value of the immediately preceding rotational acceleration is large, even if the user actually releases the handle 14, the high frequency of the rotational acceleration It may take time for the value of the component to fall below the threshold value. In this case, it takes a long time to brake the rear wheel 13 to stop the electrically power assisted walking vehicle 10. On the other hand, when the measured value of the rotational acceleration exceeds a predetermined upper limit value, the control unit 16 considers that the rotational acceleration is equal to this upper limit value and processes the rotational acceleration signal by the low-pass filter. good. As a result, even when the measured value of the rotational acceleration increases momentarily, the time from when the user releases the steering wheel 14 to when the rear wheel 13 is braked can be shortened.

(3) Since the left and right feet are generally moved alternately when a person walks, the rotational acceleration of the rear wheel 13 changes according to the movement of the user's foot. Therefore, if there is no change in acceleration for a time longer than the walking cycle, it is considered that the person has not operated. There are various methods for observing periodic fluctuations in acceleration, but it is convenient to determine this period based on whether or not the acceleration exceeds the threshold value. When the rotational acceleration of the rear wheel 13 is smaller than a predetermined positive threshold value, it may be determined that the user has released his hand from the steering wheel 14 or the like of the electrically power assisted walking vehicle 10. In this case, it is possible to effectively prevent the control unit 16 from erroneously detecting the acceleration due to the output of the motor 20 as an operation by the user and erroneously determining that the user has released the handle 14. Further, when the rotational acceleration of the rear wheel 13 is larger than a predetermined negative threshold value, it may be determined that the user has released his / her hand from the steering wheel 14 or the like of the electrically power assisted walking vehicle 10. In this case, the control unit 16 erroneously detects the downward movement of the electrically power assisted walking vehicle 10 due to gravity as an operation by the user, and effectively prevents the user from erroneously determining that he / she has released his / her hand from the steering wheel 14. be able to. Further, it may be determined from both the positive threshold value and the negative threshold value. Further, when the absolute value of the rotational acceleration of the rear wheel 13 is equal to or less than the threshold value, the count is increased (measures the time during which the absolute value of the rotational acceleration is continuously equal to or less than the threshold value), and the count exceeds a certain amount. In this case, it may be determined that the user has released his / her hand from the handle 14 or the like of the electrically assisted walking vehicle 10.

(4) For the rotational acceleration of the rear wheels 13, the total value of the left and right rear wheels 13 may be used. Alternatively, when each of the left and right rear wheels 13 is judged and the value of the high frequency component of both the left and right rear wheels 13 is smaller than a predetermined threshold value (AND condition), or one of the left and right rear wheels 13 is used. When the value of the high frequency component is smaller than a predetermined threshold value (OR condition), it may be determined that the user has released his hand from the handle 14 or the like of the electrically power assisted walking vehicle 10.

As described above, according to the present embodiment, the control unit determines whether or not the user is operating the electrically assisted walking vehicle 10 based on the change in the rotational acceleration of the rear wheels 13. This makes it possible to determine whether or not the user is operating the electrically power assisted walking vehicle 10 without providing a grip sensor or the like on the steering wheel 14. Therefore, when the user releases his / her hand from the steering wheel 14, it is possible to prevent the electric assisted walking vehicle 10 from moving against the intention of the user. Further, by attaching the grip sensor to the handle 14, it is possible to prevent the cost of the electrically assisted walking vehicle 10 from increasing. Further, since the handle 14 is not provided with the grip sensor or the like, it is not necessary to arrange the wiring of the grip sensor or the like around the handle 14. In particular, when the height of the handle 14 can be adjusted, it is not necessary to route the wiring to the movable portion for height adjustment, so that the structure of the movable portion can be simplified.

Further, according to the present embodiment, the control unit 16 signals the rotational acceleration of the rear wheels 13, and when the high frequency component of the rotational acceleration is smaller than a predetermined threshold value, the user uses the electrically assisted pedestrian vehicle 10. Judge that you are not operating. As a result, it is possible to determine with high accuracy whether or not the user is operating the electrically assisted walking vehicle 10 without providing a grip sensor or the like on the steering wheel 14.

Further, according to the present embodiment, when the rotational acceleration of the rear wheel 13 exceeds a predetermined upper limit value, it is considered that the rotational acceleration is equal to this upper limit value, and the signal of the rotational acceleration is signal-processed. As a result, even if the measured value of the rotational acceleration increases momentarily, the time from when the user releases the steering wheel 14 to when the rear wheel 13 is braked can be shortened.

Further, according to the present embodiment, when it is determined that the user is not operating the electrically assisted walking vehicle 10, the control unit 16 controls the motor 20 to brake the rear wheels 13. As a result, even when the user releases his / her hand from the steering wheel 14 on an inclined surface such as a slope, there is no possibility that the electrically assisted walking vehicle 10 will move unnecessarily.

Further, according to the present embodiment, after the braking of the rear wheels 13 is started, the braking of the rear wheels 13 is continued while the rotational acceleration of the rear wheels 13 is zero or a negative value. This prevents the control unit 16 from erroneously determining that the electrically power assisted walking vehicle 10 has been operated by the user.

Further, according to the present embodiment, the control unit 16 calculates the rotational acceleration of the rear wheel 13 based on the signal from the speed detection sensor 22. In this case, the control unit 16 can determine whether or not the user is operating the electrically assisted walking vehicle 10 by the speed detection sensor 22 provided in advance on the rear wheel 13. This makes it possible to determine whether or not the user is operating the electrically power assisted walking vehicle 10 without providing a grip sensor or the like on the steering wheel 14.

In the above embodiment, the control unit 16 has described the case where the pair of rear wheels 13 is braked by controlling the motor (braking unit) 20, but the present invention is not limited to this, and the rear wheels 13 and / Or the front wheels 12 may be braked. Further, in the present embodiment, the pair of rear wheels (wheels) 13 has been described as an example, but the present invention is not limited to this, and the starting wheels, rolling wheels, and idle wheels (guide wheels) are connected to the entire area so as to surround them. Any infinite track may be used, such as a wheel of a attached footboard, a caterpillar, or the like.

(Modified example of the control method in this embodiment)
Next, in the present embodiment, various modifications of the control method for controlling the motor 20 by the control unit 16 will be described. The control method according to the following modification may be performed in parallel with the control method according to the above-described embodiment, or may be performed independently of the above-mentioned control method.

(Modification example 1 of control method)
When the tilt detection sensor 23 determines that the electrically assisted walking vehicle 10 is on an ascending inclined surface and the rear wheel 13 is rotating backward, the control unit 16 operates the electrically assisted walking vehicle 10. You may judge that it is not.

In this case, first, the control unit 16 implements the assist control mode (step S21 in FIG. 4). During this time, the rotation of the rear wheels 13 of the electrically assisted walking vehicle 10 is assisted by the motor 20.

Subsequently, the control unit 16 determines whether or not the electrically assisted walking vehicle 10 is located on the ascending inclined surface based on the signal from the inclination detection sensor 23 (step S22 in FIG. 4). Specifically, the control unit 16 determines whether or not the electrically assisted walking vehicle 10 is located on an ascending inclined surface having a predetermined angle or more based on the measured value of the inclination detection sensor 23.

When the electrically assisted walking vehicle 10 is located on an ascending inclined surface, the control unit 16 then determines whether or not the user is operating the handle 14 or the like of the electrically assisted walking vehicle 10 (FIG. 4). Step S23).

Specifically, the control unit 16 detects whether or not the rear wheel 13 is rotating backward based on the rotation speed signal from the speed detection sensor 22.

Here, in general, when the user is operating the steering wheel 14 or the like of the electrically power assisted walking vehicle 10 on an ascending inclined surface, it is considered that the rear wheel 13 is rotating forward or is stationary. On the other hand, when the user does not operate the steering wheel 14 or the like of the electrically power assisted walking vehicle 10, it is considered that the rear wheels 13 rotate backward on the uphill inclined surface (see FIG. 5).

Therefore, when the electrically assisted walking vehicle 10 is on an uphill slope and the rear wheel 13 is rotating backward, it is determined that the user has not operated the electrically assisted walking vehicle 10 (released). be able to. In this case, the control unit 16 controls the motor (braking unit) 20 to cause the motor 20 to function as a dynamic brake, for example, and brake the rear wheels 13 (step S24 in FIG. 4). This makes it possible to prevent the electrically assisted walking vehicle 10 from unintentionally moving when the user is not operating the electrically assisted walking vehicle 10 on an uphill slope.

(Modification example 2 of the control method)
The control unit 16 determines that the electrically assisted walking vehicle 10 is located on an inclined surface inclined to the left and right by the inclination detection sensor 23, and the rear wheel 13 located above the inclined surface among the pair of rear wheels 13 When the rear wheel 13 located below the inclined surface is stationary or rotating forward and stationary or rotating backward, it may be determined that the user is not operating the electrically assisted walking vehicle 10.

That is, first, the control unit 16 implements the assist control mode (step S31 in FIG. 6). In this case, the rotation of the rear wheel 13 of the electrically assisted walking vehicle 10 is assisted by the motor 20.

Subsequently, the control unit 16 determines whether or not the electrically assisted walking vehicle 10 is located on an inclined surface inclined to the left or right based on the signal from the inclination detection sensor 23 (step S32 in FIG. 6). Specifically, the control unit 16 determines whether or not the electrically assisted walking vehicle 10 is located on an inclined surface inclined to the left or right by a predetermined angle or more, based on the measured value of the inclination detection sensor 23.

When the electrically assisted walking vehicle 10 is located on an inclined surface inclined to the left or right, the control unit 16 determines whether or not the user is operating the handle 14 or the like of the electrically assisted walking vehicle 10 (FIG. 6). Step S33).

Specifically, the control unit 16 determines whether the left and right rear wheels 13 are rotating forward, rotating backward, or stationary, respectively, based on the rotation speed signal from the speed detection sensor 22. Is detected. In this case, the speed detection sensor 22 independently measures the rotation speeds of the left and right rear wheels 13, and transmits each rotation speed as a signal to the control unit 16.

Here, in general, when the user operates the steering wheel 14 or the like of the electrically power assisted walking vehicle 10 on an inclined surface inclined to the left or right, it is considered that both the left and right rear wheels 13 are stationary or rotate forward. On the other hand, when the user does not operate the handle 14 or the like of the electrically power assisted walking vehicle 10 on an inclined surface inclined to the left or right, the rear wheel 13 located above is stationary or rotates forward and is located below. It is considered that the rear wheel 13 is stationary or rotates backward (see FIG. 7). This is because the electrically power assisted walking vehicle 10 moves downward from the front wheel 12, which is a free wheel.

Therefore, when the electrically power assisted walking vehicle 10 is on an inclined surface inclined to the left and right, and the rear wheel 13 located above is stationary or rotated forward, and the rear wheel 13 located below is stationary or rotated rearward. , It can be determined that the user is not operating the electrically assisted walking vehicle 10. In this case, the control unit 16 controls the motor (braking unit) 20 to cause the motor 20 to function as a dynamic brake, for example, and brake the rear wheels 13 (step S34 in FIG. 6). This makes it possible to prevent the electrically assisted walking vehicle 10 from unintentionally moving when the user is not operating the electrically assisted walking vehicle 10 on an inclined surface inclined to the left or right.

When the speed of rotation in front of the rear wheel 13 located above the inclined surface becomes a predetermined value or more while braking the rear wheel 13 in this way, the user uses the electrically assisted walking vehicle 10. You can think of it as trying to turn. Therefore, the control unit 16 may release the braking of the rear wheel 13 when the speed of rotating forward of the rear wheel 13 located above the inclined surface becomes a predetermined value or more.

As another modification, when the rear wheel 13 is a free wheel and the rotation of the front wheel 12 is detected, the rear wheel 13 which is a free wheel moves downward. Therefore, when the user does not operate the steering wheel 14 or the like of the electrically power assisted walking vehicle 10, it is considered that the front wheel 12 located above is stationary or rotates backward, and the front wheel 12 located below is stationary or rotates forward. Be done. In this case, when the rear wheel 13 located above is stationary or rotating backward and the rear wheel 13 located below is stationary or rotating forward, the control unit 16 allows the user to use the electrically assisted walking vehicle 10. It is determined that the vehicle is not being operated, and the rear wheel 13 is braked.

Further, in the above, the rotation of the front wheels 12 and / or the rear wheels 13 is detected, but in addition, the rotation movement of the vehicle body of the electrically assisted walking vehicle 10 is performed by using an inclination sensor such as an inclination detection sensor 23 or a gyro sensor. Can be controlled in the same way by detecting.

(Modification example of components of electrically power assisted walking vehicle)
Next, a modification of the components of the electrically power assisted walking vehicle 10 will be described. In the present embodiment, a pair of rear wheels (wheels) 13 has been described as an example, but the present invention is not limited to this, and the starting wheels, rolling wheels, and idle wheels (guide wheels) are connected to the entire area so as to surround them. Any infinite track such as a ring of a footboard, a caterpillar, etc. may be used.

Although each embodiment of the present invention has been described above, each of the above embodiments is presented as an example and is not intended to limit the scope of the invention. Each of the above embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. Each of the above embodiments and modifications thereof is included in the scope and gist of the invention as well as the invention described in the claims and the equivalent scope thereof.

10 Electric assisted walking vehicle 11 Frame 12 Front wheel 13 Rear wheel 14 Steering wheel 16 Control unit 20 Motor (braking unit)
21 Battery 22 Speed detection sensor 23 Tilt detection sensor

Claims (10)

An electric vehicle with wheels or tracks
A braking unit that brakes the wheel or the endless track,
Based on the amount of change in the acceleration of the electric vehicle, the user does not operate the electric vehicle, but determines whether or not the electric vehicle is moving at a distance from the user's hand to control the braking unit. With a control unit,
When the control unit determines that the user does not operate the electric vehicle and the electric vehicle is moving at a distance from the user's hand, the control unit controls the braking unit to control the wheel or the endless. Braking the track to prevent the electric vehicle from moving,
The control unit determines that the user is not operating the electric vehicle when the amount of change in the acceleration is smaller than a predetermined threshold value .
The amount of change in the acceleration is the value of the high-frequency component per unit time of the rotational acceleration of the wheel or the infinite orbit, and the high-frequency component is the squared average of the difference between the measured value of the rotational acceleration and the low-frequency component. An electric vehicle characterized by being obtained as an absolute value . The electric vehicle according to claim 1, wherein the control unit considers that the acceleration is equal to the upper limit value when the acceleration exceeds a predetermined upper limit value. An electric vehicle with wheels or tracks
A braking unit that brakes the wheel or the endless track,
Based on the change in the acceleration of the electric vehicle, the user does not operate the electric vehicle, but determines whether or not the electric vehicle is moving at a distance from the user's hand to control the braking unit. With a control unit,
When the control unit determines that the user does not operate the electric vehicle and the electric vehicle is moving at a distance from the user's hand, the control unit controls the braking unit to control the wheel or the endless. Braking the track to prevent the electric vehicle from moving,
The control unit has maintained a state in which the acceleration is smaller than a predetermined positive threshold value for a longer time than a predetermined time , or a state in which the acceleration is larger than a predetermined negative threshold value for a longer time than a predetermined time. An electric vehicle, characterized in that it is determined that the user is not operating the electric vehicle at least one of the times. An electric vehicle with wheels or tracks
A braking unit that brakes the wheel or the endless track,
Based on the amount of change in the acceleration of the electric vehicle, the user does not operate the electric vehicle, but determines whether or not the electric vehicle is moving at a distance from the user's hand to control the braking unit. With a control unit,
When the control unit determines that the user does not operate the electric vehicle and the electric vehicle is moving at a distance from the user's hand, the control unit controls the braking unit to control the wheel or the endless. Braking the track to prevent the electric vehicle from moving,
After starting braking of the wheel or the endless track, the control unit continues braking of the wheel or the endless track while the acceleration of the electric vehicle is zero or a negative value .
The amount of change in the acceleration is the value of the high-frequency component per unit time of the rotational acceleration of the wheel or the infinite orbit, and the high-frequency component is the squared average of the difference between the measured value of the rotational acceleration and the low-frequency component. An electric vehicle characterized by being obtained as an absolute value . The present invention further comprises a speed detection sensor for detecting the rotational speed of the wheel or the infinite track, and the control unit calculates the acceleration of the electric vehicle based on a signal from the speed detection sensor. The electric vehicle according to any one of 1 to 4. Further equipped with a tilt detection sensor that detects the tilt of the electric vehicle,
When the tilt detection sensor determines that the electric vehicle is located on an ascending inclined surface and the wheel or the endless track is rotating backward, the user operates the electric vehicle. The electric vehicle according to any one of claims 1 to 4, wherein it is determined that the vehicle is not. Further equipped with a tilt detection sensor that detects the tilt of the electric vehicle,
A pair of left and right wheels or tracks are provided.
The control unit determines by the tilt detection sensor that the electric vehicle is located on an inclined surface inclined to the left or right, and the wheel or the endless track located on one of the upper side and the lower side of the inclined surface is When the wheel or the endless track located at the other of the upper side and the lower side of the inclined surface is stationary or rotating forward, the user is not operating the electric vehicle. The electric vehicle according to any one of claims 1 to 5, wherein the determination is made. An electric vehicle with wheels or tracks
A braking unit that brakes the wheel or the endless track,
The tilt detection sensor that detects the tilt of the electric vehicle and
The tilt detection sensor determines that the electric vehicle is located on an inclined surface inclined to the left or right, and the wheel or the endless track located above or below the inclined surface rotates stationary or forward. However, when the wheel or the endless track located on the other of the upper side and the lower side of the inclined surface is stationary or rotating backward, the user does not operate the electric vehicle and leaves the user's hand. A control unit that determines that the electric vehicle is moving and controls the braking unit is provided.
When the control unit determines that the user does not operate the electric vehicle and the electric vehicle is moving at a distance from the user's hand, the control unit controls the braking unit to control the wheel or the endless. An electric vehicle characterized in that the track is braked so that the electric vehicle does not move. It is a braking method of an electric vehicle provided with wheels or an endless track, and it is determined whether or not the user is operating the electric vehicle based on the amount of change in the acceleration of the electric vehicle, and the wheels or the endless track are set. Braking,
When the user does not operate the electric vehicle and determines that the electric vehicle is moving at a distance from the user's hand, the wheels or the endless track are braked so that the electric vehicle does not move. west,
When the amount of change in acceleration is smaller than a predetermined threshold value, it is determined that the user is not operating the electric vehicle.
The amount of change in the acceleration is the value of the high-frequency component per unit time of the rotational acceleration of the wheel or the infinite orbit, and the high-frequency component is the squared average of the difference between the measured value of the rotational acceleration and the low-frequency component. A braking method for an electric vehicle, characterized in that it is obtained as an absolute value . A braking method for an electric vehicle having a pair of left and right wheels or tracks, wherein the electric vehicle is located on an inclined surface inclined to the left and right, and the wheels or infinitely located on one of the upper side and the lower side of the inclined surface. When the track is stationary or rotating forward, and the wheel or track located on the other of the upper and lower sides of the inclined surface is stationary or rotating backward, the user does not operate the electric vehicle, and the said. It is determined that the electric vehicle is moving at a distance from the user's hand, and the wheels or tracks are braked.
When the user does not operate the electric vehicle and determines that the electric vehicle is moving at a distance from the user's hand, the wheels or the endless track are braked so that the electric vehicle does not move. A braking method for electric vehicles.

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