JPH08161046A - Automatic traveling vehicle - Google Patents

Abstract

PURPOSE: To provide an automatic traveling vehicle which can be stopped in its original travel path if a guide line sensor gets out of order during automatic travel. CONSTITUTION: If the guide line sensor gets out of order, steering control based upon the output of the guide line sensor is impossible, so stop control for smoothly stopping the vehicle is performed (step ST8) and the steering control by a steering motor is stopped (step ST11). Then a steering clutch is powered OFF and a steering wheel and a steering shaft are connected (step ST12). Consequently, manual steering by steering wheel operation is possible from the start of the stop control to the stopping of the vehicle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic vehicle which travels while performing automatic steering along a guide line laid on a predetermined route.

[0002]

2. Description of the Related Art Conventionally, various types of automated vehicles for carrying luggage such as golf bags and people in golf courses have been proposed. An example of this type of automatic vehicle is, for example, Japanese Patent Laid-Open No.
The one disclosed in Japanese Patent Publication No.-80844 is known.
The automatic vehicle disclosed in this publication has a guide wire embedded along a predetermined route, and a guide wire sensor for magnetically detecting the guide wire is provided on the vehicle side to automatically steer the vehicle. It is configured.

[0003]

By the way, in the automatic vehicle disclosed in the above publication, when the guide wire sensor fails, the vehicle is automatically controlled to stop.
Since the vehicle travels a certain distance until it completely stops, there is a possibility that the vehicle deviates from the original guidance route during this time.

The present invention has been made under such a background, and provides an automatic vehicle capable of stopping the vehicle in the original traveling route even if the guide wire sensor fails during automatic traveling. Is intended.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a guide wire sensor for detecting a guide wire laid on a predetermined path and outputting a detection signal according to a distance from the guide wire, and the guide wire sensor. Based on the output, steering control means for steering control so that the vehicle does not deviate from the guide line, and switching means for switching the steering state between manual steering by a steering wheel operation and automatic steering by the steering control means according to a switching instruction. When,
When abnormality is detected by the abnormality detecting means while traveling in the steering state by the automatic steering based on the output of the guide wire sensor and the abnormality detecting means detects the abnormality, the manual steering is performed by the switching means. And a stop control means for stopping the traveling of the vehicle as well as issuing a switching instruction to.

[0006]

According to the present invention, the guide wire sensor detects the guide wire laid on a predetermined route and outputs a detection signal corresponding to the distance from the guide wire, and the steering control means is the guide wire sensor. Based on the output of the steering control, the vehicle is controlled so as not to deviate from the guide line, and the switching means switches the steering state between manual steering by the steering wheel operation and automatic steering by the steering control means according to the switching instruction, and the abnormality detection means. Detects an abnormality of the sensor based on the output of the guide wire sensor, and the stop control means, when the abnormality is detected by the abnormality detection means while traveling in the steering state by automatic steering, the stop control means switches to manual steering. The switching instruction is issued and the vehicle stops running.
Accordingly, when the steering control is disabled due to a failure of the guide wire sensor, the occupant can perform the manual steering by operating the steering wheel from the time when the stop control is started until the vehicle is stopped.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. (1) Configuration of Embodiment FIG. 1 is a block diagram showing the configuration of an automatic vehicle according to an embodiment of the present invention. The automatic vehicle shown in this figure is used as, for example, a golf cart used in a golf course, and is equipped with an engine 1 as in a normal automobile, and the engine 1 is provided with a V-belt type automatic transmission 1a. A transmission 3 for transmitting the supplied driving force to rear wheels 2a, 2b which are drive wheels, a shift lever 3a connected to this transmission 3 for switching the traveling direction to "forward" or "reverse", and front wheels 2c, 2d. Steering wheel 4 for steering the vehicle, accelerator pedal 5 and governor 6 for adjusting the throttle opening to change the vehicle speed,
It has a brake pedal 7 for braking the vehicle and a mechanical brake mechanism such as drum brakes 8a to 8d.

Further, the automatic vehicle is capable of automatic traveling in addition to ordinary manual traveling (hereinafter referred to as manual traveling). The controller 9 for controlling the automatic traveling, the steering driver 10, Steering motor 11, throttle motor 12, throttle clutch 41, brake motor driver 13, brake motor 14, electromagnetic brake 15, other guide wire sensor 16, fixed point sensor 17, rear-end collision prevention sensor 18, obstacle sensors 19a, 19b, bumper switch 20a. , 20b
There are various switching mechanisms such as a sensor group and a switch group, etc., and a steering clutch 40 and the like, which are automatically disengaged by switching between manual traveling mode and automatic traveling mode.

The controller 9 is composed of a CPU (central processing unit) 9a, a memory (not shown), etc., and executes a predetermined control program to perform traveling control described later.

When the steering relay 10a is turned on by the controller 9 during automatic traveling, the steering driver 10 supplies a steering motor 11 with a drive current corresponding to a steering instruction signal output from the controller 9.
And the steering shaft 4a is rotated. At this time, the steering wheel 4 is separated from the steering shaft 4a by the steering clutch 40, and the manual operation is disabled. Further, if the steering wheel 4 freely rotates during automatic traveling, it gives an occupant an unpleasant feeling.
I try to separate it.

The throttle motor 12 is driven in response to an opening instruction signal output from the controller 9 during automatic traveling, and the throttle clutch 41 is also engaged in response to an on instruction signal output from the controller 9. It At this time, the switching device 42 switches the drive system of the engine 1 from the governor 6 side to the throttle motor 12 side. As a result, during automatic traveling, the throttle opening is adjusted according to the drive amount of the throttle motor 12 instead of the operation amount of the accelerator pedal 5.

When the controller 9 turns on the brake relay 13a during automatic traveling, the brake motor driver 13 supplies a drive current corresponding to the braking command value output from the controller 9 to the brake motor 14. As a result, the brake motor 14 drives the drum brakes 8a to 8d provided on each of the four wheels 2a to 2d via the gear 14a and the switching mechanism 43 to brake the vehicle. In addition, the brake pedal 7
Is connected to the drum brakes 8a to 8d via the switching mechanism 43 even during automatic traveling, and manual braking is also possible.

The electromagnetic brake 15 is a brake device for stopping, which is on / off controlled by the controller 9, and is spline-fitted to a rotary shaft 50 for transmitting the rotation of the engine 1 to the transmission 3 as shown in the figure. The disk 15a and the fixed platen 15b fixed to the outer wall of the transmission 3 and the like so as not to contact the rotating shaft 50 and to face the disk 15a. Since the disk 15a is spline-fitted to the rotary shaft 50, the disk 15a rotates integrally with the rotary shaft 50 while being movable in the axial direction of the rotary shaft 50. In addition, fixed board 1
5b is composed of a permanent magnet that generates a magnetic field that attracts the disk 15a, and an electromagnet that is excited by the controller 9 so as to cancel the magnetic field of the permanent magnet.

That is, in the electromagnetic brake 15, the excitation of the electromagnet is turned on during traveling, and the magnetic field of the permanent magnet is canceled by this magnetic field, so that the attraction force to the disk 15a is lost, and as a result, the rotating shaft 50 is rotated. On the other hand, braking is no longer effective. On the other hand, if the excitation to the electromagnet is turned off immediately before stopping,
The disk 15a is fixed to the fixed plate 15b by the magnetic force of the permanent magnet.
The rotary shaft 50 is braked.

Further, the controller 9 uses the electromagnetic brake 1
If the configuration is such that the magnitude of the exciting current supplied to the electromagnet is made variable and the magnitude of the braking force to be applied to the vehicle is controlled, instead of simply controlling ON / OFF of 5, the electromagnetic force as an automatic traveling brake device is obtained. Drum brakes 8a to 8d driven by the brake 15 and the brake motor 14 described above.
It is possible to use and together. For example, the electromagnetic brake 15 is mainly used as a first system brake device for supplying a small braking force for speed control during traveling, and the drum brakes 8a to 8d are mainly supplied with a large braking force for stopping the vehicle. You may make it use as a brake system of a 2nd system.

The guide wire sensor 16 is mounted on a T-shaped arm 51 mounted on the front end of the vehicle so as to be horizontally rotatable.
It is placed in three places so as to face the ground. The guide wire sensor 16 magnetically detects a guide wire (not shown) embedded in a golf course or the like, and outputs a detection signal to the controller 9 according to the distance from the guide wire. Based on the output of the guide wire sensor 16, the controller 9 performs steering control so that the vehicle does not depart from the course.

The fixed point sensor 17 is attached to a predetermined position of the vehicle so as to face the ground, and magnetically defines a fixed point composed of a plurality of permanent magnets (not shown) embedded at predetermined intervals in a golf course or the like. To detect. For example, if this fixed point is composed of the magnetic poles of three permanent magnets, and the arrangement thereof is S pole, N pole, and N pole, the fixed point sensor 17
Outputs a detection signal corresponding to the pattern of the arrangement of the magnetic poles to the controller 9. The pattern of the arrangement of the magnetic poles is used as an instruction signal for the controller 9 to control traveling of the vehicle such as stop, start, and speed.

The rear-end collision prevention sensor 18 is provided at the front end portion of the vehicle, and is a radio wave emitted by an automatic vehicle traveling in front (a radio wave is transmitted backward to the rear end portion of each automatic vehicle, not shown). Is provided) and outputs a detection signal corresponding to the intensity to the controller 9. Based on the output of the rear-end collision prevention sensor 18, the controller 9 determines whether or not the distance to the preceding vehicle is equal to or less than a predetermined set value, and when it is determined that the distance is less than or equal to the set value, the rear-end collision prevention is prevented. Stop the vehicle to do so.

The obstacle sensors 19a and 19b are light-reflecting infrared sensors provided at two positions on the left and right of the front end of the vehicle, and are obstacles (including living things such as people and animals) existing in front of the vehicle. A detection signal corresponding to the distance between and is output (this output increases as the distance decreases).
The controller 9 controls the respective obstacle sensors 19a and 19b.
Is compared with the first and second set values, respectively, and if either one of the sensor outputs (distance to the obstacle) is greater than or equal to the first set value, the vehicle is decelerated and the first set value is set. When it is equal to or larger than the second set value which is larger than the value, the vehicle is stopped. This avoids contact with obstacles.

The bumper switches 20a and 20b are on / off switches provided at two positions on the left and right of the gap between the front bumper 52 and the vehicle body. The bumper switches 20a and 20b are normally in the off state, but are turned on when the front bumper 52 is pressed by some obstacle. The controller 9 turns on one of the bumper switches 20a and 20b,
Stop the vehicle.

The accelerator switch 21 is an on / off type switch that is turned on in response to depression of the accelerator pedal 5. The controller 9 stops the vehicle when the accelerator pedal 5 is depressed and the accelerator switch 21 is turned on even though the vehicle is automatically traveling.

The brake switch 22 is an on / off type switch which is turned on in response to depression of the brake pedal 7. When the brake pedal 5 is depressed during the automatic traveling, the braking force by the brake motor 14 and the braking force by the pedal operation are added, and the traveling load of the vehicle (resistance that tends to hinder traveling) increases. However, in the speed control during automatic traveling, when the traveling load of the vehicle increases, the controller 9 controls to increase the throttle opening in order to maintain the current vehicle speed. For this reason, even if the occupant depresses the brake pedal 5 during automatic traveling, sufficient braking is not applied. Therefore, when the brake pedal 5 is depressed during automatic traveling, the brake switch 22 detects the pedal operation during automatic traveling in order to stop the control of the throttle opening.

The forward switch 23a is a shift lever 3a.
The switch is turned on and off in conjunction with the operation of, and is turned on when the shift lever 3a is set to the "forward" position, and turned off when operated a little from that position. Since the vehicle does not move backward in the automatic running, it is premised that the shift lever 3a is always in the "forward" position during the automatic running. Therefore, the shift lever 3a is on the "neutral" side or "reverse" during automatic traveling.
If it is operated a little to the side, the controller 9 detects this by turning off the forward switch 23a,
Stop the vehicle smoothly.

The reverse switch 23b, like the forward switch 23a, is a switch that turns on and off in conjunction with the operation of the shift lever 3a. When the shift lever 3a is set to the "reverse" position, it turns on. When it is operated to any other position (“neutral” or “forward” position), it turns off. When the reverse switch 23b is turned on, the alarm buzzer 53 is turned on and an alarm sound is generated. This alarm buzzer 53 is used to detect any abnormality in the vehicle (guide wire sensor 16) even when the vehicle is not moving backward.
If a failure occurs, etc.), an alarm sound corresponding to each abnormality is generated.

In addition, as a sensor group for detecting the running state of the vehicle, the transmission 3 detects the vehicle speed 1.
A pair of vehicle speed sensors 24a, 24b, a rotation speed sensor (not shown) for detecting the engine speed for the engine 1, a throttle potentiometer 25 for detecting the throttle opening degree for the carburetor 1b, and a drum brake 8a for the gear 14a.
8d and a brake limit switch 26 for detecting whether or not the rotation angle of the brake motor 14 exceeds a certain limit value due to a stroke abnormality of the mechanical brake mechanism including the braking force transmission path.

Here, the pair of vehicle speed sensors 24a, 24a
Each of 4b is adapted to detect the vehicle speed individually, but the two are provided in this way in order to detect a failure of the vehicle speed sensor. That is, the controller 9 controls the sensors 24a and 24b when the difference between the vehicle speed detection values obtained from the sensors 24a and 24b exceeds a predetermined value.
b is considered to be out of order.

The operation panel 54 is provided in the vicinity of the driver's seat, and is a rotary type main switch 54a capable of switching the main power source off, manual drive mode and automatic drive mode by dial operation. A start / stop button 54b that is alternately instructed to start and stop by an operation, an emergency stop button 54c that is instructed to perform an emergency stop by a pressing operation, an indicator light 54d that displays various kinds of information such as a running state, and an abnormality is notified. The warning lamp 54e is configured to display a warning for When the automatic drive mode is selected by the main switch 54a, the controller 9 switches the drive mode of the vehicle to automatic drive and performs control for automatic drive described later.

The operator of the caddy or the like operates the operation panel 54
The vehicle body has a transmitter 55a having the same function as the start / stop button 54b, and the vehicle body receives a start / stop instruction transmitted by a wireless signal from the transmitter 55a and supplies it to the controller 9. A device 55b is provided. This makes it possible to remotely control the autonomous vehicle.

(2) Operation of the Embodiment Next, the operation of this embodiment will be described. FIG. 2 is a flowchart showing a control routine executed by the controller 9. In the following, referring to this flowchart, the operation of the embodiment will be described with reference to an automatic traveling operation during normal operation, an operation when the shift lever 3a is operated during automatic traveling, and an operation when a system abnormality occurs during automatic traveling. The operation when a stop instruction is given during automatic traveling and the manual traveling operation will be separately described.

Automatic Driving Operation in Normal Time First, when the main switch 54a is turned on, the controller 9 activates the control routine shown in FIG. 2 and advances the processing to step ST1. In step ST1, it is determined whether the dial of the main switch 54a is set to "automatic traveling" or "manual traveling". In this case, since "automatic traveling" is set, the process proceeds to step ST2.

In step ST2, it is determined whether or not the shift lever 3a is set to the "forward" position, that is, whether or not the forward switch 23a is turned on.
In the normal state, the forward switch 23a is turned on, so the process proceeds to step ST3.

In step ST3, various parts of the vehicle system, such as various sensor groups and switch groups, are scanned to determine whether any abnormality has occurred. In this case, since no abnormality has occurred, the process proceeds to step ST4.

In step ST4, the start / stop button 5
In 4b, it is determined whether or not there is a start instruction. Here, when the start / stop button 54b of the operation panel 54 or the start / stop button (not shown) of the transmitter 55a gives a start instruction, the process proceeds to step ST5. Step S
At T5, the steering clutch 40 is energized to disconnect the steering wheel 4 from the steering shaft 4a. This allows
Manual steering by the steering wheel operation is disabled, and rotation of the steering wheel 4 due to automatic steering is prevented.

Then, in step ST6, the throttle motor 12 is driven to open the throttle to a predetermined opening, and the engine 1 is started. Then, after the traveling is started, the throttle opening and the braking force are adjusted based on the outputs of various sensors such as the vehicle speed detection value and the traveling control is performed. Further, in step ST7, based on the output of the guide wire sensor 16, the steering motor 11 is driven so that the vehicle does not deviate from the guide wire, and steering control is performed. Thus
While there is no abnormality in each part of the system or there is no stop instruction, the above-described operations of steps ST1 to ST7 are repeated to perform automatic traveling.

Operation when the shift lever 3a is operated during automatic traveling When the shift lever 3a is moved even a little from the "forward" position during automatic traveling, the forward switch 23a is turned off, which is the same as in step ST2 described above. To be detected.
As a result, the controller 9 advances the process to step ST8.

At step ST8, the brake motor 14 is driven to stop the vehicle smoothly, and stop control is performed. Then, until the vehicle speed gradually decreases and the vehicle speed detection value is determined to be "0" in step ST10, the steering control is performed in step ST7, and the above step S
Apply smooth braking at T8.

When the vehicle speed detection value becomes "0", the steering control is stopped for a certain period of time, and then the steering control is stopped in step ST11. That is, the vehicle speed detection value is "0".
However, the steering control is continued for a certain period of time because there is a possibility that the vehicle is actually moving. Then, in step ST12, the power supply to the steering clutch 40 is turned off, and the steering wheel 4 and the steering shaft 4a are connected. As a result, the vehicle is stopped in a state where manual steering by operating the steering wheel is possible.

Operation When System Abnormality Occurs During Autonomous Driving For example, when the following abnormalities occur, it is regarded as a system abnormality. a) Abnormal voltage of battery (not shown) That is, the battery voltage is not within the predetermined range. b) Engine over-rotation, that is, the number of revolutions of the engine 1 exceeds a predetermined threshold value.

C) Vehicle speed over, that is, the detected vehicle speed is higher than the target vehicle speed by a predetermined value or more. d) Vehicle speed sensor abnormality That is, the difference between the vehicle speed detection values obtained from the two vehicle speed sensors 24a and 24b exceeds a predetermined value. e) Throttle abnormality That is, the difference between the command value to the throttle motor 12 and the detection value of the throttle potentiometer 25 exceeds a predetermined value.

F) Failure of guide wire sensor 16, that is, the output of at least one of the three guide wire sensors 16, 16, 16 is "0" volt, or at least one guide wire is The output difference between the previous control cycle and the current control cycle of the sensor has exceeded the specified threshold.

When at least one of the above-exemplified abnormalities is detected during automatic traveling, the controller 9 determines that the system is abnormal in step ST3 described above,
The process proceeds to step ST8. In step ST8,
As in the case described above, stop control for smoothly stopping the vehicle is performed.

Then, in step ST9, it is determined whether or not the abnormality of the system is caused by a failure of the guide wire sensor 16. That is, when the abnormality of the system is caused by the failure of the guide wire sensor 16, the contents of the processing to be performed below are different, so the determination is made here.

Here, the system abnormality is due to the guide wire sensor 1.
When the cause is the failure of 6, the process proceeds to step ST11. In step ST11, since the steering control based on the output of the guide wire sensor 16 is impossible, the relay 10
The steering control by the steering motor 11 is stopped by turning off a. In this case, the current command value may be set to "0" to stop the steering control. And step S
At T12, the power supply to the steering clutch 40 is turned off, and the steering wheel 4 and the steering shaft 4a are connected. As a result, manual steering can be performed by operating the steering wheel from the start of the stop control to the stop of the vehicle.

On the other hand, if it is determined in step ST9 that the system abnormality is due to a cause other than the failure of the guide wire sensor 16, the process proceeds to step ST10.
Go to. After that, as in the case described above, the vehicle is smoothly stopped while performing the steering control.

Operation when a stop instruction is given during automatic traveling During the automatic traveling, the start / stop button 54b of the operation panel 54,
Emergency stop button 54c or start of transmitter 55a /
When a stop instruction is given by any of the stop buttons (not shown), this stop instruction is detected in step ST4 described above, and the process proceeds to step ST8. After that,
As in the case described above, the vehicle is smoothly stopped while performing steering control.

Manual traveling operation When the main switch 54a is set to "manual traveling", it is determined that the traveling mode is the manual traveling in the above-mentioned step ST1, and the process proceeds to step S.
Proceed to T13. In step ST13, the power supply to the steering clutch 40 is turned off and the steering wheel 4 and the steering shaft 4a are connected. As a result, the manual steering by the steering wheel operation becomes possible, and thereafter, the traveling is performed by the normal manual operation without performing the traveling control.

(3) Summary As described above, according to the present embodiment, when the stop instruction or other abnormality of the system is detected during the automatic traveling, the stop control is performed to smoothly stop the vehicle. When a failure of the guide wire sensor 16 that affects the control is detected, the steering control is stopped, and the stop control is performed in a state where the manual steering by the steering wheel operation is possible. As a result, even when steering control is disabled due to a failure of the guide wire sensor 16, the vehicle can be smoothly stopped while allowing the occupant to operate the steering wheel.

(4) Modification Example In this embodiment, the failure of the guide wire sensor 16 has been described as an example of the influence on the steering control. However, it is not limited to the failure of the guide wire sensor 16 and steering control cannot be performed. It is possible to perform the smooth stop control in a state in which the manual steering by the steering wheel operation is possible even when the other abnormality is detected in the case of the system abnormality.

[0049]

As described above, according to the present invention, when the steering control is disabled due to a failure of the guide wire sensor or the like, the occupant can be stopped from when the stop control is started until the vehicle is stopped. Since the vehicle can perform the manual steering by operating the steering wheel, the vehicle can be stopped in the original travel route.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an automatic vehicle according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the embodiment.

[Explanation of symbols]

4 ... Steering wheel 8a-8d ... Drum brake, 9 ... Controller (steering control means, abnormality detection means, stop control means), 10 ... Steering driver (steering control means), 11 ... Steering motor (steering control means), 12 ... Throttle Motor, 13 ... Brake motor driver (stop control means), 14 ... Brake motor (stop control means), 15 ... Electromagnetic brake (stop control means), 16 ... Guide wire sensor, 40 ... Steering clutch (switching means).

Claims (1)

[Claims] 1. A guide wire sensor that detects a guide wire laid on a predetermined route and outputs a detection signal according to the distance from the guide wire, and a vehicle guides the vehicle based on the output of the guide wire sensor. Steering control means for steering control so as not to deviate from the line, switching means for switching the steering state between manual steering by steering wheel operation and automatic steering by the steering control means in response to a switching instruction, and output of the guide wire sensor Based on the above, the abnormality detecting means for detecting an abnormality of the sensor, and when the abnormality is detected by the abnormality detecting means while traveling in the steering state by the automatic steering, the switching means is instructed to switch to the manual steering. In addition, the automatic traveling vehicle is provided with stop control means for stopping the traveling of the vehicle.