JPH05260804A - Device for controlling traveling of working vehicle for mowing lawn - Google Patents

Abstract

PURPOSE:To properly control traveling even in change of lawn density in one operation stroke. CONSTITUTION:A device for controlling traveling of working vehicle for mowing lawn is equipped with a deviation detecting means 11 for discovering a deviation X of a boundary L between an untreated working ground A and a treated working ground B from a proper position based on lawn existence detecting means 22 and 23 for discovering the existence of lawn in the width direction of vehicle body and information of the existence detecting means 22 and 23 and with a lawn density detecting means 13 for discovering law density at a given interval along the traveling direction of the untreated working ground A at the following adjoining working stroke side during traveling of one working stroke of mutually parallel plural working strokes. A control means 12 for regulating traveling so as to automatically travel a working vehicle V according to a working stroke based on information of the deviation X is constituted in such a way that a limit value XL against the deviation X is set smaller with smaller density of lawn at each given interval obtained by the lawn density detecting means 13 and when the deviation X becomes larger than the limit value XL, the limit value XL is treated as the deviation X.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to lawn presence / absence detecting means for detecting the presence / absence of lawn at predetermined intervals along the lateral direction of a vehicle body, and based on the information of the lawn presence / absence detecting means, an unprocessed work site and processing Based on the displacement detection means for detecting the displacement in the lateral width direction from the proper position of the vehicle body with respect to the boundary with the completed work site and the displacement information of this displacement detection means, the work vehicles are set in parallel with each other. The present invention relates to a traveling control device for a lawn mowing work vehicle, which is provided with a control means for controlling traveling so as to automatically travel along each of a plurality of work strokes.

[0002]

2. Description of the Related Art A traveling control device for a lawnmower vehicle of this type is
It is used for a self-propelled work vehicle for performing lawn mowing work without manpower. In the past, the presence or absence of turf at a predetermined interval in the vehicle body width direction orthogonal to the vehicle body traveling direction is determined by, for example, a photo interrupt. Of a plurality of sensors of the above formula are arranged side by side at the above-mentioned predetermined intervals along the vehicle body width direction, or are detected at a position corresponding to the above-mentioned predetermined interval while swinging the sensors along the vehicle body width direction, and the detection information thereof is obtained. From this, the position of the boundary between the unprocessed work site and the processed work site is determined, and the difference between the proper position where the vehicle body should be located and the current position with respect to this boundary is detected as the deviation in the lateral direction. Based on this deviation detection information, the vehicle body is automatically driven along each of a plurality of work strokes while maintaining the vehicle body at an appropriate position with respect to the boundary between the unprocessed work site and the processed work site. I was driving control.

[0003]

However, the density (density) of the grass at the lawn mowing work target is not constant, but changes depending on factors such as location and season. The error in detecting the boundary between both work sites may be large. Especially when the density of grass is small (sparse state), the unprocessed work land (uncut land) is erroneously detected as the processed work land (cut land). Despite the fact that the car body is not displaced so much with respect to the boundary position, there was a risk that the car body would be steered to approach the unprocessed work site and left uncut. On the other hand, the conventional means have not been able to effectively deal with it.

The present invention has been made in view of the above circumstances, and an object thereof is to appropriately respond to a change in the turf density even when the turf density changes with the traveling of one work stroke. The work vehicle is caused to travel in a state in which the deviation detection error in the lateral width direction is minimized.

[0005]

A characteristic configuration of a traveling control device for a lawnmower working vehicle according to the present invention is such that, when traveling one working stroke of the plurality of working strokes, the next working stroke side adjacent thereto is A lawn density detecting means for detecting the lawn density for each predetermined section along the traveling direction of the untreated work site is provided, and the control means is obtained by the lawn density detecting means during traveling of the next work stroke. As the density of the grass in each of the predetermined sections is smaller, the limit value for the deviation detected by the deviation detecting means is set to be smaller in each of the predetermined sections, and the deviation becomes larger than the limit value. In that case, the limit value is set as the deviation.

[0006]

According to the characteristic construction of the present invention, when the lawnmower vehicle travels along each work stroke, for example, according to the density of the lawn detected in each predetermined section before the travel of the work stroke, for example, In a section where the grass density is low, it is considered that the reliability of the deviation detection in the lateral direction of the vehicle body detected based on the information of the grass presence detection means is low, so a small limit value for the deviation detection value. Is set to limit so that the value does not have a large deviation. On the other hand, in a section where the grass density is high, it is considered that the reliability of the deviation detection in the lateral direction of the vehicle body, which is detected based on the information of the grass presence detection means, is high. Allow a large deviation value by setting a value.

[0007]

Therefore, according to the characteristic construction of the present invention, even if the density of the grass in each work stroke of the lawnmower working vehicle changes finely along the traveling direction within the stroke, the change occurs. Correcting the deviation value from the proper position of the car body, for example, when the turf density changes to a small value, the car body unnecessarily enters the unprocessed work side to cause uncut areas, etc. The problem can be prevented, and when the turf density changes significantly, the vehicle body can be accurately controlled while maintaining the proper position along the boundary.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIGS. 4 to 6, a rotary blade 2 for lawn mowing is attached to the lower portion of a working vehicle V equipped with an engine E, and a steering idler is provided at the front and rear of the working vehicle V. A lawn mowing work vehicle is configured by attaching a front wheel 1F and a pair of left and right drive rear wheels 1L and 1R to which the driving force of the engine E is transmitted via the drive case 3. The front wheel 1F is passed through a steering mechanism including a steering gear 1A that directly steers the front wheel 1F, a steering motor M1 for automatic steering, and a motor gear 1B that transmits the driving force of the steering motor M1 to the steering gear 1A. An encoder 14 that is attached to the work vehicle V and that detects the number of rotations of the front wheel 1F is provided on the rotary shaft portion of the front wheel 1F. Further, the work vehicle V is provided with a flux gate type geomagnetic sensor S0 using a toroidal core for detecting the current azimuth of the work vehicle V during traveling.

As shown in FIG. 2, on the front side of the work vehicle V, four grass height detecting sensors S1, S2, S3, S which are reflection type photo interrupters for detecting the presence or absence of uncut grass.
Rocking mechanism 2 for rocking back and forth 4 in the vehicle width direction of work vehicle V
3 are distributed and arranged, and the turf height detection sensor S
1, S2, S3 and S4 detect the grass condition where the grass is not cut when the grass height is large, and the grass condition where the grass is cut when the grass height is small. To detect. Therefore, the grass height detection sensors S1, S2, S3, S4 constitute the grass presence detection sensor 22.

In the swing mechanism 23, a front end of the work vehicle V is pivotally mounted at its base end to be rotatable about its longitudinal axis, and a bifurcated arm 24 having a fore end is positioned by a spring 27 in the machine advancing direction. The cam mechanism 25 is arranged so that the eccentric cam 25A abuts on the auxiliary arm 24A attached to the base end portion of the arm 24.
At each forked end of the arm 24, there is a space W in the vehicle width direction.
The turf height detection sensors S1 and S2 arranged apart from each other
Alternatively, the lawn height detection sensors S3, S4 are attached via the attachment member 26. The mounting member 26 is
Lawn height detection sensors S1, S2 or lawn height detection sensor S
In order to adjust the ground height of S3 and S4, the vertical position is adjusted by the vertical adjustment mechanism provided in the middle thereof, and then the tip side portion 26B is fixed. With the above-described configuration, the eccentric cam 25A is used for the sensor swing motor m.
When rotated (see FIG. 1), the arm 24 swings in the vehicle width direction, and the pair of left and right lawn height detection sensors S1 and S2 or the lawn height detection sensors S3 and S4 respectively scan a scanning distance W. /
Only two round trips are scanned.

Therefore, each of the lawn height detection sensors S1 and S2 or the lawn height detection sensors S3 and S4, which are swung by the swing mechanism 23, scans for the presence or absence of lawn at a predetermined ground height. The distance W / 2 is sampled at intervals of 8 divisions, whereby a pair of sensors S1, S
16 pieces of grass presence / absence data D0 to D15 are obtained by the swing scanning of 2 or S3, S4. Each data D0 to D15
Is digital data indicating "1" when the grass is detected and "0" when the grass is not detected. The sampling interval is the potentiometer G provided on the rotation shaft of the eccentric cam 25A.
It is determined by detecting the scanning position by. As described above, the grass presence / absence detection sensor 22 including the grass height detection sensors S1, S2, S3, S4 and the swing mechanism 23 detect the presence / absence of grass at predetermined intervals along the lateral direction of the vehicle body. The detection means 22 and 23 will be comprised.

The mounting member 26 is pivotally supported by the arm 24 so as to be swingable back and forth in the traveling direction with its upper base end serving as a fulcrum. A projecting portion 26A that projects to the front is provided. Between this projecting portion 26A and the tip of the arm 24, a spring 28 for urging the mounting member 26 toward the front side of the machine body is provided, and the mounting member 26 An adjusting screw 29 for adjusting the angle is screw-fitted and supported by the protruding portion 26A in a state where the tip end of the adjusting screw 29 abuts the arm 24 by the urging force of the spring 28. Thereby, the turf height detection sensor S1,
When S2 or the lawn height detection sensors S3, S4 collide with a foreign matter or the like, the rearward falls to avoid damage to the lawn height detection sensor as much as possible, and the rearward fall collides with the foreign matter or the like. Since it is limited to only the height detection sensor, the detection operation of other grass height detection sensors can be continuously performed.

As shown in FIG. 7 and FIG. 8, the driving rear wheels 1L, 1R located on the turning center side at the time of turning are floated on the inside of the pair of left and right driving rear wheels 1L, 1R. It is freely movable up and down to a descending state in which it descends and an ascending state in which the driving rear wheels 1L and 1R located on the side of the center of turning after the turning is completed are raised and the turning center is formed in the lowered state. A pair of left and right lifting type grounding bodies 9 are attached to the work vehicle V through a grounding mechanism, and
The grounding portion 9A of the lifting / lowering grounding body 9 that grounds to the ground is supported by the base end side of the lifting / lowering grounding body 9 in a rotatable state about the vertical axis. In the grounding mechanism, bent portions of a pair of left and right doglegged links 4 are attached to the drive case 3 so as to be swingable around respective fulcrums P1 and P2, and a lifting grounding body 9 is attached to one end of the link 4. A spring 5 for urging the elevating grounding body 9 upward is attached to the other end, and the other end of the link 4 is grounded to the elevating grounding body 9 against the urging force of the spring 5. It is composed of a cam mechanism 6 for rocking operation.

The cam mechanism 6 includes a cam 6A and a cam 6A.
It is composed of a pair of gears 7 for rotating the gears and a grounding motor 8 connected to the gears 7.
With each rotation, the pair of left and right lift-type grounding bodies 9 are connected to each other by the pair of left and right drive rear wheels 1 on the side of the lift-type grounding body 9.
The descending state in which the L and 1R are lowered so as to float and the ascending state in which the lifted driving rear wheels 1L and 1R are raised so as to contact the ground are alternately repeated.

As shown in FIG. 1, a control device H utilizing a microcomputer is provided. This control device H
Signals from the turf height detection sensors S1, S2, S3, S4, the potentiometer G, the geomagnetic sensor S0, and the encoder 14 are input. Further, the control device H outputs a drive signal to the steering motor M1, the sensor swinging motor m, and the grounding motor 8. Further, the control device H is connected to a memory M for storing information.

Using the memory M and the geomagnetic sensor S0, the direction of the first work stroke K1 in which the work vehicle V is directed by the worker at the start of work, that is, the unprocessed work site A and the processed work site B, The direction indicated by the boundary L (see FIG. 3)
The angle L between the direction J of the geomagnetism detected by the geomagnetic sensor S0 and the reference direction θ ₀ is stored in the memory M, so that the boundary L between the unprocessed work site A and the processed work site B is stored.
The reference azimuth setting means 10 for setting the direction indicated by as the reference azimuth is configured.

Further, by using the control device H, based on the information of the lawn presence / absence detecting means 22 and 23, the position of the vehicle body from the proper position with respect to the boundary L between the unprocessed work site A and the processed work site B is determined. Deviation detecting means 1 for detecting deviation X in the width direction
1 is configured, and based on the displacement information of the displacement detecting means 11, control for traveling control is performed so that the work vehicle V automatically travels along each of a plurality of work strokes set in parallel with each other. Means 12 are configured.

That is, while the work vehicle V is oriented in the direction of the initially set reference azimuth θ ₀ , the 16 lawn presence / absence data D0 to D15 obtained as described above are calculated by the following equation (i).
And (ii), the deviation X from the proper position in the lateral width direction of the work vehicle V with respect to the boundary L is obtained, and the steering motor M1 is controlled so that the deviation X becomes zero. When the lawn height detection sensors S3, S4 on the right side in the traveling direction of the work vehicle V are used, the equation (i) is used, and the lawn height detection sensors S1, S2 on the left side are used. Then, the formula (ii) is used.

[0020]

## EQU1 ## X = 8- (D0 + D1 +-+ D15) (i) or

X = (D0 + D1 +-+ D15) -8 (ii) Specifically, in the case of the formula (i), if the deviation X is negative, the work vehicle V is on the untreated land A side. Therefore, if the deviation X is positive, the work vehicle V is deviated to the treated land B side and therefore to the untreated land A side. Further, in the case of the formula (ii), if the deviation X is positive, the work vehicle V is displaced to the untreated area A side, and therefore the corrected operation is performed to the treated area B side (the left side in the traveling direction in FIG. 3). The deviation X
Is negative, the work vehicle V is deviated to the treated land B side, and therefore the vehicle is corrected and steered to the untreated ground A side (right side in the traveling direction in FIG. 3). From the above, in a proper steering state, the pair of lawn height detection sensors S1 and S2 located on the processed land B side.
Alternatively, the boundary L coincides with the central position of S3 and S4.

Further, by utilizing the control device H, the pair of lawn height detection sensors S located on the side of the unprocessed land A.
Based on the information of 1, S2 or S3, S4, when traveling one work stroke Kn of the plurality of work strokes, traveling of the unprocessed work site A on the side of the next work stroke Kn + 1 adjacent thereto. A turf density detecting means 13 is configured to detect the density of turf for each predetermined section set to a length of about 1 m along the direction in four stages of dense, slightly dense, sparse, and slightly sparse (see FIG. 3). ,
Further, the control means 12 detects the deviation detection means 11 as the density of the grass in each of the predetermined sections obtained by the grass density detection means 13 is smaller during traveling of the next work stroke Kn + 1. The limit value XL for the deviation X is set to be small for each of the predetermined intervals, and when the deviation X becomes larger than the limit value XL, the limit value XL is set as the deviation X. It is configured. The deviation X and the limit value XL are compared by the magnitude of the absolute value.

More specifically, the absolute value of the limit value XL of the deviation X is set to 4 in correspondence with each of the four levels of the detected density of the grass, that is, dense, slightly dense, sparse, and slightly sparse. 3, 2,
The limit value XL is set to 1 when the lawn height detection sensors S3 and S4 on the right side in the traveling direction of the work vehicle V are used (in the case of the formula (i)). ) Is attached with a positive sign, and the left turf height detection sensor S
When 1 and S2 are used (in the case of formula (ii)), a negative sign is added. As a result, the limit value XL for the right sensor and the limit value X for the left sensor having the same absolute value but different signs are used.
Two sets of limit values XL of L are prepared.

Next, the control operation of the control unit H will be described with reference to the flow charts shown in FIGS. 9 and 10.

[0025] First, the driving start stores to initialize the direction toward the work vehicle V to the reference direction theta _0, adjust the steering direction of the front wheels 1F to this reference direction theta _0. When the vehicle starts traveling, the lawn presence / absence data D0 to D15 detected by the detection means 22 are input to detect the position of the boundary L, and from this, the deviation X from the proper position of the work vehicle V is detected.
To calculate. Next, it is determined whether or not the traveling stroke is the first work stroke. Since it is the first stroke at the beginning, the subsequent flow from the calculation of the azimuth deviation Δθ described below is executed. If it is not the first stroke, the lawn density detected by the lawn density update processing routine (FIG. 10) described below is input for each of the sections of the currently traveling stroke, and based on this, the limit value of the deviation X is entered. X
Set L. As described above, two sets of the limit value XL, that is, the limit value XL for the right sensor and the limit value XL for the left sensor are prepared.

Next, it is judged whether the currently used lawn presence detection sensor is the right side sensor or the left side sensor, and if it is the right side sensor, the deviation X is compared with the limit value XL for the right side sensor. If is larger, the deviation X is replaced by the limit value XL for the right sensor, and if not larger, the value of the deviation X remains the detected value. On the other hand, in the case of the sensor on the left side, the deviation X is compared with the limit value XL for the left side sensor, and if the deviation X is smaller, the deviation X is limited to the limit value XL for the right side sensor.
, And the value of the deviation X remains the detected value if it is not small.

Next, the azimuth deviation Δθ = θ−θ ₀ is calculated from the difference between the current detected azimuth θ and the reference azimuth θ _0, and the deviation X and the azimuth deviation Δθ obtained as described above are respectively determined. Multiply the gain factors p and q and calculate the steering angle θ _{ST using the} following formula.
Then, the steering operation is performed at this steering angle θ _ST .

[Equation 2] θ _ST = p · X + q · Δθ

If the processed land B is detected when all the grass presence / absence data D0 to D15 are "0", it is detected that the end of one work stroke has been reached. The liftable grounding body 9 on one side of the rear wheels 1L and 1R is used as a turning center, and the driving rear wheels 1L and 1R on the side other than the turning center are driven to turn the work vehicle V while the steering operation is performed in the turning direction. It will be. At this time, the geomagnetic sensor S0 is used to confirm the direction of the work vehicle V, information indicating whether the direction is 180 ° with respect to the direction K1 of the first work stroke, and the turning center detected by the encoder 14. It is determined that the vehicle is heading for the next work stroke based on the traveling amounts of the rear drive wheels 1L and 1R on the other side.

The grass density updating process will be described with reference to FIG. In addition, this process is 1m
It is executed 3 times (1 time / about 33 cm) every time you run. First, after confirming that the work vehicle V is traveling in a predetermined section, the lawn presence detection sensor 22 on the untreated land A side, that is, the pair of lawn height detection sensors S1 and S2 or lawn height detection is detected. The 16 grass presence / absence data D0 to D15 detected by swinging the sensors S3 and S4 in the lateral direction of the vehicle body are input, and the data is accumulated three times in one section. When data of three times, that is, 48 pieces of grass presence / absence data are accumulated in one section, based on the ratio (%) of the grass presence data “1” of the 48 pieces of grass presence / absence data, the ratio (% ), The grass density of the four stages is determined to be dense, slightly dense, sparse, or slightly sparse, and the grass density of the section is updated. After that, the above-mentioned accumulated data is cleared in preparation for the determination of the grass density in the next section.

[Other Embodiment] In the above embodiment, the lawn presence detecting means 22 and 23 for detecting the presence or absence of lawn at predetermined intervals along the lateral direction of the vehicle body are configured to swing in the lateral direction of the vehicle body. Alternatively, a plurality of sensors corresponding to the above intervals may be fixedly provided in the lateral direction of the vehicle body. Further, the detection interval, that is, the number of detection positions is not limited to 16 in the above embodiment.

Further, in the above-described embodiment, during the traveling of one working stroke, the density of the grass is detected for each predetermined section along the traveling direction of the unprocessed work site A on the side of the next working stroke adjacent thereto. As the lawn density detecting means 13, the lawn presence / absence detection sensor 22 on the untreated work site A side, which is not used for detecting the deviation of the vehicle body, is used. It can also be on the ground A side. Further, although the length of the predetermined section is set to 1 m, the length of the section can be set arbitrarily. It is also possible to use another detecting means as the lawn density detecting means 13.

In the above embodiment, the present invention is applied to a lawnmower work vehicle, but it can be applied to other various work vehicles for automatic traveling such as grass mowing work vehicles.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the structures of the accompanying drawings by the entry.

[0034]

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a control device.

FIG. 2 is a plan view of turf presence detecting means.

FIG. 3 is an explanatory diagram of a work form

FIG. 4 is a schematic plan view of a lawnmower work vehicle.

[Fig. 5] Schematic side view of the lawnmower

FIG. 6 is a front side view of the lawn presence detection means.

FIG. 7 is a rear view of the turning mechanism.

FIG. 8 is an operation explanatory view of the turning mechanism.

FIG. 9 is a flowchart of control operation.

FIG. 10 is a flowchart of control operation.

[Explanation of symbols]

 A unprocessed work site B processed work site L boundary V work vehicle X deviation XL limit value 11 deviation detection means 12 control means 13 lawn density detection means 22, 23 lawn presence / absence detection means

Claims (1)

[Claims] 1. A lawn presence / absence detecting means (22, 23) for detecting the presence or absence of lawn at predetermined intervals along the lateral direction of the vehicle body, and an unprocessed state based on information of the lawn presence / absence detecting means (22, 23). A deviation detecting means (11) for detecting a deviation (X) in a lateral width direction from an appropriate position of the vehicle body with respect to a boundary (L) between the work area (A) and the processed work area (B), and this deviation. A control means (12) for controlling travel of the work vehicle (V) so as to automatically travel along each of a plurality of work strokes set in parallel with each other based on the deviation information of the detection means (11). A traveling control device for a lawnmower provided, wherein the unprocessed work site (A) on the side of the next work process adjacent to the work process when traveling one work process of the plurality of work processes.
A turf density detecting means (13) for detecting the density of turf for each predetermined section along the traveling direction of, and the control means (12) is configured to detect the turf density during the traveling of the next work stroke. 13), the smaller the grass density for each of the predetermined sections, the smaller the limit value (XL) for the deviation (X) detected by the deviation detecting means (11) is set for each of the predetermined sections. Then, when the displacement (X) becomes larger than the limit value (XL), the limit value (XL) is set as the displacement (X). Control device.