JP2802514B2 - Steering control device for self-propelled vehicles - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a steering control device for a self-propelled vehicle used for agriculture, civil engineering work, etc. The present invention relates to a steering control device for a self-propelled vehicle that can detect when a running vehicle cannot run normally and take measures.

(Prior Art) Conventionally, as a device for detecting the current position of a moving object such as the above-mentioned self-propelled vehicle, means for scanning a light beam generated by the moving object in a circumferential direction around the moving object, There has been proposed an apparatus which is fixed to at least three places away from the body and includes light reflecting means for reflecting light in the incident direction, and light receiving means for receiving light reflected from the light reflecting means (Japanese Patent Application Laid-Open (JP-A) no. Akira
59-67476).

The traveling direction of the self-propelled vehicle is controlled based on the detection information of the position detection means, and the self-propelled vehicle performs scheduled work.

By the way, trees and
There are obstacles such as tools and bicycles necessary for work,
This may hinder the traveling of the self-propelled vehicle.

As measures against such problems, for example, Japanese Patent Application Laid-Open
As described in No. 47606, there is an autonomous traveling work vehicle that mounts an obstacle detection sensor on the self-propelled vehicle and avoids this when it detects an obstacle .

(Problems to be Solved by the Invention) By the way, the obstacle detection sensor provided in the self-propelled vehicle (autonomous vehicle) protrudes from the traveling surface of the self-propelled vehicle to a certain height or more. Such an object such as a tree can be reliably detected. However, it detects other obstacles that hinder the traveling of the vehicle, such as dents in the running surface such as depressions and grooves, or obstacles with a short height, and slightly rising portions on the ground surface, and soft muddy grounds. Not easy.

When such obstacles cannot be detected and the self-propelled vehicle cannot avoid these obstacles, it climbs on the bulging portion, falls in the dent portion, or slips on the soft muddy ground. There is a problem that the vehicle is stuck and cannot continue running.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, to detect that a self-propelled vehicle is stuck, automatically stop the engine of the self-propelled vehicle, and further issue an alarm according to the cause of the stall. It is an object of the present invention to provide a steering control device for a self-propelled vehicle that can perform the following.

(Means and Actions for Solving the Problems) In order to solve the above-mentioned problems and achieve the object, the present invention provides the latest self-position of a self-propelled vehicle calculated at a predetermined cycle and the previously calculated self-position. Means for determining that the self-propelled vehicle is not moving when the difference between the self-positions is smaller than the reference value; means for detecting whether or not the wheels of the self-propelled vehicle are rotating; Nevertheless, a first feature is that a means for outputting an idling warning and outputting at least a first abnormality detection signal for stopping the engine when the self-propelled vehicle is not moving is provided.

Further, the present invention provides an engine stop detecting means, a means for detecting the presence or absence of fuel, and, when the engine is stopped,
A second abnormality detection signal for generating one of an alarm indicating fuel shortage and an alarm indicating another cause of abnormality according to the output of the fuel presence / absence detection means.
There is a feature.

According to the present invention having the above configuration, when the self-propelled vehicle is stuck, an alarm indicating the cause of the stuck self-propelled vehicle can be issued. Also, the wheels of the self-propelled car are rotating,
In addition, when the self-propelled vehicle is not moving, an alarm can be issued to stop the engine.

Embodiment An embodiment of the present invention will be described below with reference to the drawings. FIG. 6 is a perspective view showing a vehicle equipped with the control device of the present invention and a light reflector disposed in a work area of the vehicle.

In FIG. 1, a self-propelled vehicle 1 is a work vehicle used for agricultural work such as a lawn mower, and a cutter blade (not shown) for lawn mower is mounted on a bottom surface thereof to perform a predetermined lawn mowing operation. Will be Further, the self-propelled vehicle 1 is equipped with a steering control device for causing the self-propelled vehicle 1 to travel along a preset traveling course.

A rotary table 4 driven by a motor 5 is provided above the self-propelled vehicle 1. The rotary table 4 is provided with a light emitting device 2 for generating a light beam and a light receiving device 3 for receiving reflected light of the light beam. The light emitting device 2 includes a light emitting diode that generates light, and the light receiving device 3 includes a photodiode that receives incident light and converts the light into an electric signal (both are not shown).

The rotary encoder 7 is provided so as to interlock with the drive shaft of the rotary table 4, and counts pulses output from the rotary encoder 7 to
The rotation angle of the turntable 4 can be detected.

The reflectors 6 are arranged at three places around the work area of the vehicle 1, and the positions where the reflectors 6 are arranged serve as reference points for detecting the position and the traveling direction of the vehicle 1. The reflector 6
Is provided with a reflecting surface for reflecting the incident light in the incident direction. As the reflector 6, a so-called corner cube prism or the like, which is conventionally commercially available, can be used.

When the light beam generated by the light emitter 2 is reflected by the light reflector 6, the reflected light is received by the light receiver 3. Then, based on the light receiving timing and the pulse output of the encoder 7, the position and the traveling direction of the self-propelled vehicle 1 traveling in the work area are detected.

A configuration of a control device for performing steering control of the self-propelled vehicle 1 based on the detection result of the position and the traveling direction of the self-propelled vehicle 1 will be described with reference to the block diagram shown in FIG.

In FIG. 2, the light beam emitted from the light emitter 2 is scanned in the direction of rotation of the turntable 4 and reflected by the reflector 6. The light beam reflected by the reflector 6 enters the light receiver 3 and is detected as information representing the azimuth of the reflector 6 with respect to the traveling direction of the self-propelled vehicle.

The counter 9 counts the number of pulses output from the rotary encoder 7 as the rotary table 4 rotates. Then, the count value of the pulse is transferred to the angle detecting unit 10 each time the light receiving unit 3 receives the reflected light. The angle detection unit 10 calculates the opening angle of each reflector 6 with respect to the traveling direction of the self-propelled vehicle 1 based on the count value (= azimuth angle) of the pulse transferred each time the reflected light is received.

In the position / traveling direction calculation unit 13, a straight line connecting two reference points among these reference points based on each detected reflector 6, that is, an opening angle between three reference points where the respective reflectors 6 are arranged. The coordinates and the traveling direction of the vehicle 1 in the xy coordinate system with x as the x axis are calculated. The xy coordinate system is set in advance by measuring the position of each reference point by an appropriate means and based on the position information. The specific calculation procedure of the coordinates and the traveling direction and the calculation formula thereof are described in detail in the invention (Japanese Patent Application No. 63-116689) filed by the present inventors, so that the description is omitted.

The calculation result in the position / traveling direction calculation unit 13 is input to the comparison unit 25. The comparison unit 25 compares the data representing the traveling course set in the traveling course setting unit 16 with the coordinates and traveling direction of the self-propelled vehicle 1 obtained by the position / traveling direction calculation unit 13. Difference Δx of self-propelled vehicle 1 with respect to
And the angle difference Δθf in the traveling direction is detected.

The position difference Δx and the angle difference Δθf in the traveling direction are input to the steering unit 14, and the steering unit 14 determines the steering angle of the front wheels 17 of the self-propelled vehicle 1 based on these data.

The steering motor M connected to the front wheels 17 of the self-propelled vehicle 1 is driven based on the determined steering angle. The steering angle of the front wheels 17 by the steering motor M is detected by a steering angle sensor 15 provided on the front wheels of the self-propelled vehicle 1 and fed back to the steering unit 14. The drive unit 18 controls the start / stop of the engine 19 and the operation of the clutch 20 that transmits the power of the engine 19 to the rear wheels 21.

Next, a configuration of a control device for detecting that the self-propelled vehicle 1 has become unable to travel will be described with reference to FIG. First
In the figure, the same reference numerals as those in FIG. 2 indicate the same or equivalent parts.

In FIG. 1, an x coordinate indicating the position of the self-propelled vehicle 1 detected by the position / traveling direction calculation unit 13 is input to a current x coordinate storage unit 23, and a y coordinate is input to a current y coordinate storage unit 24. You.

When the x-coordinate is input to the current x-coordinate storage unit 23, the value stored in the storage unit 23 at the previous sampling is the old x-coordinate.
The data is transferred to the coordinate storage unit 26. In the x-direction displacement detection unit 28,
The difference between the values stored in the current x-coordinate storage unit 23 and the old x-coordinate storage unit 26, that is, the amount of movement of the self-propelled vehicle 1 in the x direction during the scheduled sampling period is detected.

Similarly, when the y coordinate is input to the current y coordinate storage unit 24,
The value stored in the storage unit 24 at the time of the previous sampling is
The data is transferred to the old y coordinate storage unit 27. Then, in the y-direction displacement detector 29, the difference between the values stored in the current y-coordinate storage unit 24 and the old y-coordinate storage unit 27, that is, the self-propelled vehicle 1 moves in the y-direction during the scheduled sampling period. The amount is detected.

The values detected by the x-direction displacement detection unit 28 and the y-direction displacement detection unit 29 are input to the x-direction displacement comparison unit 30 and the y-direction displacement comparison unit 31, respectively, and are compared with reference values.

As a result of the comparison, when the values input to the respective comparison units 30 and 31 are smaller than the reference value, the detection signals a and b are sent to the first abnormality detection unit 32, the second abnormality detection unit 33, and the third abnormality detection unit 34. Is supplied.

The rotation detection unit 35 detects whether the engine 19 is rotating, and the on / off detection unit 36 detects whether the clutch 20 is connected (on) or disconnected (off). .

When the engine 19 is rotating, the detection signal c is supplied to the first abnormality detecting unit 32. When the engine 19 is not rotating, the detection signal c is supplied to the second abnormality detecting unit 33 and the third abnormality detecting unit 34. The detection signal d is supplied.

When the clutch 20 is on, the first abnormality detection unit 32,
The detection signal e is supplied to the second abnormality detection unit 33 and the third abnormality detection unit 34.

Further, the presence or absence of fuel in the fuel tank 37 is detected by the fuel presence / absence detection unit 38. If there is no fuel, the detection signal f is supplied to the second abnormality detection unit 33. If there is fuel, the third abnormality is detected. The detection signal g is supplied to the detection unit 34.

Each of the abnormality detection units 32, 33, supplied with the above detection signal,
When the predetermined detection signal is supplied to 34, it outputs abnormality detection signals I1, I2, I3, respectively.

Each of the abnormality detection units 32, 33, and 34 is configured by one logical operation unit, performs an operation based on the input of each detection unit, and performs detection signals I1 to
I3 may be output.

The abnormality detection signal I1 is the engine 19 and the engine 19
A cutter blade clutch (not shown) for connecting a cutter blade (not shown) so as to be able to be turned on and off freely, and is supplied to each drive unit of the clutch 20 to stop the engine 19 and the cutter blade, and to turn off the clutch 20. And an instruction signal for operating a first alarm (not shown) for informing that the wheels are idling.

Further, the abnormality detection signal I2 is supplied to each drive unit of the cutter blade clutch and the clutch 20 to stop the cutter blade, turn off the clutch 20, and activate an alarm (not shown) for notifying the fuel shortage. Becomes

Further, the abnormality detection signal I3 is output from the rotation detection unit 35,
A third alarm (not shown) for notifying of other causes that cannot be specified only by the detection means such as the off detection unit 36 and the fuel presence / absence detection unit 38, for example, a stop of the self-propelled vehicle 1 due to a failure or insufficient engine oil. Is an instruction signal for activating.

Note that, of the components shown in FIG. 1 and the components shown in FIG. 2, portions within the range shown by a chain line can be constituted by a microcomputer.

Next, the operation of this embodiment having the above configuration will be described. 3 and 4 are flowcharts showing the operation of the present embodiment,
FIG. 5 is a diagram showing a traveling course of the self-propelled vehicle 1 and an arrangement state of the reflector 6.

In FIG. 5, a reflector 6 is disposed at reference points A, B, and C, and the vehicle 1 and the work area 22 are arranged in a coordinate system having the point B as an origin and a line passing through the points B and C as an x-axis. Is represented.

The point R (Xret, Yret) indicates the return position of the self-propelled vehicle 1, and the work area 22 is (Xst, Yst), (Xst, Ye), (Xe, Yst), (X
e, Ye). The position of the self-propelled vehicle 1 is indicated by T (Xp, Yp).

FIG. 5 shows an example in which the four sides of the work area 22 are parallel to the x-axis or the y-axis for the sake of simplicity.
If reference points A, B, and C are located around 22
And the directions of the four sides of the work area 22 are arbitrary.

The control procedure will be described with reference to the flowchart of FIG.

First, in step S1, the self-propelled vehicle 1 calculated based on the current position (return position) R of the self-propelled vehicle 1 and the coordinates (Xst, Yst) of the work start position set in the traveling course setting unit 16 is set. The front wheels 17 are steered according to the steering amount of the vehicle, and the self-propelled vehicle 1 is moved to the work start position.

In step S2, Xst is set as the X coordinate Xn of the traveling course to set the traveling course.

In step S3, the traveling of the self-propelled vehicle 1 is started, and in step S4, the self-position T (Xp, Yp) and the traveling direction θf of the self-propelled vehicle 1 are calculated.

In step S5, a running disable detection process is performed according to a procedure described later with reference to FIG.

In step S6, the deviation amount from the traveling course (Δx = Xp
−Xn, Δθf) is calculated, and in step S7, the steering angle is controlled by the steering unit 14 according to the deviation amount.

In step S8, it is determined whether the self-propelled vehicle 1 is traveling in a direction away from the origin in the y-axis direction (forward direction) or traveling in a direction approaching the origin (return direction).

If the direction is a direction, it is determined in step S9 whether or not one stroke has been completed (Yp> Ye).
In step S10, it is determined whether or not one stroke has been completed (Yp <Yst). If it is determined in step S9 or S10 that one stroke has not been completed, the processing in steps S4 to S8 is performed.

If it is determined in step S9 or S10 that one stroke has been completed, then it is determined in step S11 whether all the strokes have been completed (Xp> Xe).

If all the steps have not been completed, the U-turn control of the self-propelled vehicle 1 is performed in step S12. The control of the U-turn (turning stroke) is performed, for example, as follows. Self-propelled car 1
Of the azimuth angles of the reference points A to C viewed from the self-propelled vehicle 1 based on the opening angle detected by the angle detection unit 10 with the steering angle fixed at a preset angle. When at least one of the angles falls within the predetermined angle range, the control of the turning stroke is terminated and the control returns to the steering control of the straight stroke.

In step S13, (Xn + L) is set in Xn, and the next traveling course is set.

When all the steps are completed, the process returns to the return position R (step S14), and the traveling is stopped (step S15).

Next, the operation of the traveling inability detection processing in step S5 will be described with reference to FIG.

In the figure, in step S50, the x-coordinate indicating the current position of the self-propelled vehicle 1 is read from the position / traveling-direction calculator 13 into the current x-coordinate storage 23. Along with this, the old x coordinate storage unit 26
Is updated with the data transferred from the current x-coordinate storage unit 23.

In step S51, the y-coordinate indicating the current position of the self-propelled vehicle 1 is read from the position / traveling direction calculation unit 13 into the current y-coordinate storage unit 24. Along with this, the storage contents of the old y-coordinate storage unit 27 are updated with the data transferred from the current y-coordinate storage unit 24.

In step S52, the current x coordinate storage unit 23 and the old x
An x-coordinate (current x-coordinate) indicating the current position of the self-propelled vehicle 1 and an x-coordinate (old x-coordinate) indicating the position at the time of the previous calculation are read from the coordinate storage unit 26, and the difference between the current x-coordinate and the old x-coordinate is calculated. That is, the moving amount mx of the self-propelled vehicle 1 in the x direction is calculated.

In step S53, it is determined whether the movement amount mx is equal to or less than a reference value. If the movement amount mx is equal to or greater than the reference value, the process proceeds to step S6 (FIG. 3). If the movement amount mx is equal to or less than the reference value, the process proceeds to step S54.

In step S54, the current y coordinate storage unit 24 and the old y coordinate
The y-coordinate (current y-coordinate) indicating the current position of the self-propelled vehicle 1 and the y-coordinate (old y-coordinate) indicating the position at the previous calculation are read from the coordinate storage unit 27, and the difference between the current y-coordinate and the old y-coordinate is calculated. That is, the moving amount my of the self-propelled vehicle 1 in the y direction is calculated.

In step S55, it is determined whether the movement amount my is equal to or less than a reference value. If the movement amount my is equal to or greater than the reference value, the process proceeds to step S6. If the movement amount my is equal to or less than the reference value,
Proceed to step S56.

In step S56, the on / off state of the clutch 20 is determined. If the clutch 20 is off,
Proceeding to S6, if the clutch 20 is ON, step S57
Proceed to.

In step S57, the rotation speed of the engine 19 is read.

In step S58, it is determined whether or not the engine 19 is stopped based on the read rotation speed.

If the engine 19 is not stopped, the detection result up to this point, that is, the engine 19 is rotating and the clutch 20
Is turned on, the self-propelled vehicle 1 has not moved by the reference value or more within the scheduled time, so it is determined that the wheels are spinning.

Based on the above determination result, in step S59, the abnormality detection signal I1 is output, the engine 19 and the cutter blade are stopped, and the clutch 20 is turned off.

In step S60, an alarm for notifying of idling is issued.

On the other hand, if the result of the determination in step S58 is that the engine 19 is stopped, it is next determined in step S61 whether or not there is fuel, and if there is no fuel, an abnormality detection signal I2 is output, and the signal I2 In step S62, the cutter blade clutch and clutch 20 are turned off.

In step S63, an alarm for notifying that the fuel is running out is issued.

As a result of the determination in step S61, if there is still fuel, the cause of the inability of the self-propelled vehicle 1 to travel is unknown, so only an alarm for notifying a failure is issued in step S64 and the process ends. I do.

As described above, according to the present embodiment, it is possible to detect the movement amount of the self-propelled vehicle 1 within a predetermined time based on the position information of the self-propelled vehicle 1 calculated by the position / traveling direction calculation unit 13, This detection result, the rotation detection signal of the engine 19, the clutch 20
It is possible to reliably detect whether or not the self-propelled vehicle 1 is unable to travel by comprehensively judging from the ON / OFF detection signal of the vehicle and the detection signal of the presence or absence of fuel.

If the self-propelled vehicle 1 is incapable of running, a separate abnormality detection signal is output depending on whether the cause is due to wheel idling, running out of fuel, or other causes. Then, different alarms were issued.

As a result, a person who is monitoring the work of the self-propelled vehicle 1 can recognize early that the self-propelled vehicle 1 cannot travel and can accurately know the cause of the abnormality.

(Effects of the Invention) As is clear from the above description, according to the present invention, the following effects can be obtained.

(1) When the self-propelled vehicle cannot run normally, this can be reliably detected and the engine can be stopped.

(2) Since the engine can be automatically stopped, fuel is not wasted.

(3) Since the wheels can be prevented from spinning, there is no damage to the turf due to continuous slipping in lawn mowing work or the like.

(4) Since it is possible to know the impossibility of traveling by an alarm, the monitoring labor of the operator can be reduced.

(5) Since the cause of the abnormality can be accurately known,
It is possible to return to normal running early and work efficiency is improved.

[Brief description of the drawings]

1 and 2 are block diagrams showing an embodiment of the present invention.
3 and 4 are flowcharts showing the operation of the embodiment,
FIG. 5 is an explanatory diagram of a traveling route of the self-propelled vehicle, and FIG. 6 is a perspective view showing a positional relationship between the self-propelled vehicle, a reflector, and an obstacle. DESCRIPTION OF SYMBOLS 1 ... Self-propelled vehicle, 2 ... Light-emitting device, 3 ... Light-receiving device, 6 ... Reflector, 10 ... Angle detection unit, 13 ... Position / traveling direction calculation unit, 14 ... Steering unit, 23 ... ... Current x coordinate storage unit, 24 ... Current y
Coordinate storage unit, 25: comparison unit, 26: old x coordinate storage unit, 27
... Old y-coordinate storage unit, 28... X-direction displacement detection unit, 29.
y-direction displacement detector, 30... x-direction displacement comparator, 31... y
Direction displacement comparison unit, 32 first abnormality detection unit, 33 second abnormality detection unit, 34 third abnormality detection unit, 35 rotation detection unit
36: ON / OFF detector, 38: Fuel presence / absence detector

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toru Takeda 1-4-1 Chuo, Wako-shi, Saitama Pref. Honda Technical Research Institute Co., Ltd. 62-80709 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G05D 1/02 A01B 69/00 303

Claims (3)

(57) [Claims] 1. A detecting means for detecting a self-position and a traveling direction with respect to reference points installed at at least three places around an area related to work, and detecting a traveling direction of a self-propelled vehicle based on detection information of the detecting means. In a steering control device for a self-propelled vehicle to be controlled, the self-propelled vehicle is moving when a difference between a latest self position of the self-propelled vehicle calculated at a predetermined cycle and a self-position calculated last time is smaller than a reference value. Means for determining that there is no vehicle, means for detecting whether or not the wheels of the self-propelled vehicle are rotating, and at least stopping the engine when the self-propelled vehicle is not moving despite the wheels being rotated Means for outputting a first abnormality detection signal for causing the vehicle to run. 2. The self-propelled vehicle according to claim 1, wherein the means for outputting the first abnormality detection signal further comprises means for issuing an idling warning indicating that the wheels are idling. Car steering control. 3. An engine stop detecting means, a fuel presence / absence detecting means, and an alarm indicating a fuel shortage and other causes based on an output of the fuel presence / absence detecting means when the engine is stopped. 3. The steering control device for a self-propelled vehicle according to claim 1, further comprising a second abnormality detecting means for generating the abnormality.