JP7853639B2 - Electric vehicles - Google Patents

Description

This invention relates to an electric vehicle.

An example of an electric vehicle capable of steering, driving, and stopping via a joystick is an electric wheelchair. Patent Document 1 describes an electric wheelchair equipped with a joystick that operates in a manual driving mode, an automatic driving mode with a passenger, or an automatic driving mode without a passenger.

Patent No. 6709989

In the automatic driving mode of electric vehicles, there may be situations where an emergency stop is necessary, regardless of the cause. Therefore, electric vehicles are typically equipped with a dedicated emergency stop switch that can be operated by someone nearby to bring the vehicle to an emergency. However, depending on the relative positions of the emergency stop switch and the person operating it, a relatively long time may pass between realizing the need for an emergency stop and actually operating the switch.

In view of these circumstances, the present invention aims to provide an alternative means for emergency stopping in addition to a dedicated emergency stop switch in the automatic driving mode of an electric vehicle.

To achieve the above objective, the electric vehicle according to the present invention is equipped with a joystick and a switch for emergency stop, and operates in manual driving mode or automatic driving mode. In manual driving mode, the joystick functions as a means for controlling the driving of the electric vehicle, and in automatic driving mode, the joystick functions as an emergency stop means for the electric vehicle, separate from the switch, and is not related to the normal operation of the electric vehicle. In automatic driving mode, when the joystick is operated, the motor of the electric vehicle is controlled and the electric vehicle stops, regardless of the direction of tilt of the joystick, or in automatic driving mode, when the amount of operation of the joystick is greater than or equal to a predetermined threshold, the connection between the motor of the electric vehicle and the power supply is disconnected and the electric vehicle stops, regardless of the direction of tilt of the joystick.

According to the present invention, in addition to a dedicated emergency stop switch, another means for emergency stopping can be provided in the automatic driving mode of an electric vehicle.

This is a perspective view of an electric vehicle. This is a side view of the electric vehicle. This is a functional block diagram showing the configuration of an electric vehicle. This is a flowchart showing the processes performed in electric vehicles.

The present invention will be described below based on the illustrated embodiments. However, the present invention is not limited to the embodiments described below. In the figures, the direction of arrow Fr indicates the front in the vehicle's longitudinal direction. Arrow L indicates the left side when facing the front of the vehicle, and arrow U indicates the top of the vehicle.

Figures 1 and 2 show the transport trolley 100. The transport trolley 100 is an electric four-wheeled vehicle, comprising front wheels 10 (steering wheels), rear wheels 20 (drive wheels), and a roughly rectangular grid-shaped loading platform 30.

A box-shaped base 41 is provided on the underside of the rear end 31 of the loading platform 30, facing the rear of the vehicle, so as to protrude toward the rear of the vehicle. A joystick 42 is mounted upright on the upper surface of this base 41. This joystick 42 is tilted by the user of the transport trolley 100 to control its movement. Alternatively, this joystick 42 can also be operated by a person who is not the user of the transport trolley 100 but is near it.

A box-shaped base 51 is provided on the front end surface 32 of the loading platform 30, facing the front of the vehicle, so as to protrude forward. A mushroom-shaped emergency stop switch 52 is provided on the front end surface of this base 51, so as to protrude forward. This emergency stop switch 52 is a dedicated emergency stop switch that is pressed towards the rear of the vehicle by a person near the transport trolley 100 to stop the transport trolley 100 in an emergency.

As shown in Figure 3, the transport trolley 100 further comprises a first operation signal generation unit 61, a second operation signal generation unit 62, a third operation signal generation unit 63, a mode switch 64, a controller 71, a steering motor 72, and a drive motor 73.

The first operation signal generation unit 61 is connected to the joystick 42 and generates operation signals (analog voltage signals, CAN (Controller Area Network) signals, etc.) in response to the operation of the joystick 42, and sends these operation signals to the controller 71.
The second operation signal generation unit 62 receives a signal sent from a remote transmitter 200 located outside the transport trolley 100, generates an operation signal for operating the transport trolley 100 from that signal, and sends that operation signal to the controller 71.
The third operation signal generation unit 63 receives input from external devices 300 such as sensors and cameras located outside the transport trolley 100, generates operation signals for autonomous driving using teaching, AI, map information, etc., and sends these operation signals to the controller 71.

The mode switch 64 is a switch operated by the user to switch the mode of the transport cart 100, and is connected to the controller 71. The transport cart 100 has three modes: joystick mode, remote mode, and autonomous mode. By operating the mode switch 64, one of these three modes is selected, and the selection result is sent to the controller 71.

The controller 71 controls the steering motor 72 for steering the front wheels 10 and the drive motor 73 for driving the rear wheels 20, according to the mode selected by the mode switch 64.
An emergency stop switch 52 is also connected to the controller 71. When the emergency stop switch is pressed, the controller 71 sends a motor stop signal to the steering motor 72 and the drive motor 73, regardless of which of the three modes is selected.

Figure 4 shows the processing flow by the controller 71. In step S1, the controller 71 determines whether the mode selected by the mode switch 64 is joystick mode (J/S mode), remote mode, or autonomous mode. If it is determined that the selected mode is joystick mode, then step S2 is performed. If it is determined that the selected mode is remote mode, or if it is determined that the selected mode is autonomous mode, then step S3 is performed.

Furthermore, the joystick mode can also be called the manual driving mode. Also, the remote mode and autonomous mode can be collectively referred to as the automatic driving mode.

In step S2, the controller 71 controls the steering motor 72 and the drive motor 73 based on the operation signals received from the first operation signal generation unit 61.
Furthermore, if the emergency stop switch 52 is pressed during control according to the same step, the controller 71 stops the steering motor 72 and the drive motor 73 regardless of the operation signal received from the first operation signal generation unit 61.
In this step, the controller 71 does not perform control based on the signal from the second operation signal generation unit 62, nor does it perform control based on the signal from the third operation signal generation unit 63.
Following step S2, step S1 is performed again.

In step S3, the controller 71 performs vehicle control according to either remote mode or autonomous mode.
In other words, when the selected mode is remote mode, the controller 71 controls the steering motor 72 and the drive motor 73 based on the operation signals received from the second operation signal generation unit 62.
If the selected mode is autonomous mode, the controller 71 controls the steering motor 72 and the drive motor 73 based on the operation signals received from the third operation signal generation unit 63.

In step S4, the controller 71 determines whether the joystick (J/S) 42 has been operated based on the signal from the first operation signal generation unit 61. If it is determined that the joystick 42 has been operated, step S5 is performed next; otherwise, step S1 is repeated.

In step S5, the controller 71 sends a stop signal to the steering motor 72 and the drive motor 73, stopping both motors. As a result, the transport trolley 100 stops.
In step S6, the controller 71 determines whether the stop of the transport trolley 100 has been reset. If it is determined that a reset has occurred, then step S1 is performed again; otherwise, step S5 is performed again.

If the transport cart 100 is powered on, the above reset can be performed by operating the joystick 42. For example, the transport cart 100 can be configured such that when the joystick 42 is tilted forward for 5 seconds, the buzzer on the transport cart 100 sounds, and then when the joystick 42 is returned to the neutral position, the buzzer stops and the reset is complete. In the case of a power outage, the above reset can be performed by turning the power switch of the transport cart 100 on and off again. Furthermore, a reset switch (not shown) may be provided near the joystick 42, and the above reset can be performed by operating this reset switch.

[effect]
According to the above embodiment, the transport trolley 100 can be stopped not only by the emergency stop switch 52 provided on the transport trolley 100, but also by operating the joystick 42 when in automatic driving mode.
In manual driving mode, the joystick 42 is operated to steer, drive, and stop the transport cart 100, while in automatic driving mode, it functions as an emergency stop means separate from the emergency stop switch 52.
When automatic driving mode is selected, the joystick 42 does not participate in the normal operation of the transport cart 100, but in an emergency, a person near the transport cart 100 can touch the joystick 42 to stop the transport cart 100.

In this way, the chances of someone near the vehicle stopping the transport trolley in an emergency can be increased. Furthermore, the time it takes to stop the transport trolley can be shortened.

When automatic driving mode is selected, the transport trolley 100 can be stopped by any operation of the joystick, regardless of whether the tilt is forward, backward, left, or right. Furthermore, while the force required to operate an emergency stop switch is often greater than the force required to operate a joystick, using the joystick allows for emergency stopping of the vehicle with less force than required to operate the emergency stop switch.

If the base 41 on which the joystick 42 is mounted also has a power switch (not shown) for the transport trolley 100, the options for stopping the vehicle increase further. In this case, the joystick 42 and the power switch are located very close together. As an emergency stopping option, in addition to the joystick 42 and the emergency stop switch 52, there is also the power switch, and turning off this power switch is a third method of stopping the vehicle.

[Other forms]
1) Stopping by the emergency stop switch 52 can be done by cutting off the control power supply to the transport trolley 100. And stopping by the joystick 42 in remote mode or autonomous mode may be done by cutting off the control power supply to the transport trolley 100, similar to stopping by the emergency stop switch 52, or it may be a stop that does not involve cutting off the power supply (a stop such as returning the joystick 42 to the stop point, i.e., the neutral point, in joystick mode).
2) Depending on the amount of operation of the joystick 42 in remote mode or autonomous mode, the system can be configured to either shut down by cutting off the power supply or to shut down without cutting off the power supply. For example, if the amount of operation of the joystick is greater than or equal to a predetermined threshold, the system can be configured to shut down by cutting off the power supply, and if the amount of operation of the joystick is less than the threshold, the system can be configured to shut down without cutting off the power supply.
3) Depending on the direction of joystick operation, the system can be configured to either stop by cutting off the power or stop without cutting off the power. For example, if the joystick is tilted forward, the system can be configured to stop by cutting off the power, and if the joystick is tilted backward, the system can be configured to stop without cutting off the power.
4) The shape of the joystick may be modified to make it easier to operate as a stopping device.

The above embodiment is not limited to transport trolleys, but is broadly applicable to electric vehicles, including electric wheelchairs.

In relation to the above embodiments, the following additional information is disclosed.
[Note 1]
An electric vehicle equipped with a joystick and a dedicated emergency stop switch, which operates in manual or automatic driving mode,
In the manual driving mode, the joystick functions as a means for controlling the driving of the electric vehicle.
In the aforementioned automatic driving mode, the joystick functions as an emergency stop means for the electric vehicle, separate from the switch.
Electric vehicle.

In manual driving mode, where the operator is near the electric vehicle, it is possible to quickly respond to emergencies by pressing the emergency stop switch. However, in automatic driving mode, when the operator is not near the vehicle, or when the operator is nearby but there is a certain distance to the emergency stop switch, it is often not possible to respond quickly to emergencies.
Furthermore, emergency stop switches are often surrounded by guards to prevent accidental activation, and depending on the relative positions of the vehicle and the person, it may be necessary to go around the vehicle to press the switch even if it is within reach.
By assigning an emergency stop function to the joystick, which is normally not used in automatic driving mode, stopping the vehicle in an emergency becomes easier than using a dedicated emergency stop switch.

[Note 2]
The electric vehicle as described in Appendix 1, wherein in the automatic driving mode, when the joystick is operated, the motor of the electric vehicle is controlled and the electric vehicle stops regardless of the direction of tilt of the joystick.

The motor of an electric vehicle can be stopped by either cutting off power to the motor, stopping the transmission of output signals to the motor, or by using regenerative braking.

[Note 3]
The electric vehicle as described in Appendix 1, wherein in the automatic mode, if the amount of operation of the joystick exceeds a predetermined threshold, the connection between the motor and the power supply of the electric vehicle is disconnected and the electric vehicle stops, regardless of the direction of tilt of the joystick.

If the joystick input exceeds a predetermined threshold, it is considered a high-priority emergency, and an emergency stop is possible by activating the mechanical brake. This emergency stop can be achieved by shutting off the control power supply or by independently operating the brake.

Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described herein, and various modifications and changes are possible based on the technical concept of the present invention.

100 Transport cart 10 Front wheels 20 Rear wheels 30 Loading platform 42 Joystick 52 Emergency stop switches 61-63 Operation signal generation unit 64 Mode switch 71 Controllers 72, 73 Motor

Claims (2)

An electric vehicle equipped with a joystick and a dedicated emergency stop switch, which operates in manual or automatic driving mode,
In the manual driving mode, the joystick functions as a means for controlling the driving of the electric vehicle.
In the aforementioned automatic driving mode, the joystick functions as an emergency stop means for the electric vehicle, separate from the switch, and is not involved in the normal operation of the electric vehicle.
In the automatic driving mode, when the joystick is operated, the motor of the electric vehicle is controlled to stop the electric vehicle , regardless of the direction in which the joystick is tilted.
Electric vehicle. An electric vehicle equipped with a joystick and a dedicated emergency stop switch, which operates in manual or automatic driving mode,
In the manual driving mode, the joystick functions as a means for controlling the driving of the electric vehicle.
In the aforementioned automatic driving mode, the joystick functions as an emergency stop means for the electric vehicle, separate from the switch, and is not involved in the normal operation of the electric vehicle.
In the automatic driving mode, if the amount of movement of the joystick exceeds a predetermined threshold, the connection between the motor and power supply of the electric vehicle is disconnected, and the electric vehicle stops, regardless of the direction of tilt of the joystick .
Electric vehicle.