JPS63240708A - Turn control apparatus of automatic running working vehicle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a turning control means for turning a working vehicle toward the next working step that intersects with the completion of one working step. The present invention relates to a turn control device for an automated driving vehicle equipped with a turn control device.

[Conventional technology]

Conventionally, in the above-mentioned turn control device for an automated driving work vehicle, for example, the working range is set to a rectangular shape as a standard, and the turning control device is used to change the direction from one work process to the next work process that intersects with the work process. It was configured to control turns assuming that the turning angle was a constant angle (eg, 90 degrees).

In other words, control information such as the amount of steering and travel distance in order to perform a turn at a turning angle set to a certain angle,
The work vehicle was designed to automatically turn by stylizing and storing the information in advance and driving the work vehicle based on the stored information. However, in actual working conditions, the turning angle may be other than 90 degrees. The errors caused by this are corrected after entering the next working process by another control means such as a steering control means for automatically driving the vehicle along the working process.

[Problem that the invention seeks to solve]

According to the above-mentioned conventional means, regardless of the turning angle of the actual working process, the turn is made based on the stored information set as a constant turning angle. If it is small or larger than 90 degrees, there is a risk that the approach position relative to the starting end of the next working stroke will deviate from the proper position.

If the approach position for the next work process deviates significantly from the appropriate position, not only is there a risk of unprocessed areas occurring at the starting end of the work process, but it also takes time and effort to correct them, reducing work efficiency. There are disadvantages to doing so.

Therefore, it may be possible to make the work vehicle turn by modifying the stored control information according to the turning angle from one work stroke to the next, but in that case, only one turn pattern is used. If you make a turn, the time required for the turn becomes long, which has the disadvantage of reducing work efficiency.

For example, as shown in Fig. 8, even after reaching the end of one working stroke, move the R2O forward a predetermined distance in the direction along that working stroke, and then proceed to the next working stroke while moving backward. When using a turn pattern that involves turning a predetermined distance (Riz) in the direction away from the starting end, and then turning so as to proceed straight toward the next work process, as shown in Fig. 10, the turning pattern When the angle (α-β) becomes large, as shown in FIG. 8, it becomes necessary to change the direction of the vehicle body more than when the turning angle (α-β) is small.

In other words, in order to make an accurate turn corresponding to the turning angle (α-β), there is a limit to the maximum turning angle of the steering wheels, so the above-mentioned predetermined distance (Rx+).

By increasing (R1,) as the turning angle (α-β) decreases, the direction of the vehicle body can be changed significantly, which increases the travel distance required for a turn. Not only does this have the disadvantage of requiring a larger space, but it also has the disadvantage of increasing the time required for a turn, reducing work efficiency.

The present invention was made in view of the above circumstances, and
The purpose of this is to enable efficient turns regardless of variations in the turning angle from one working stroke to the next working stroke that intersects with that working stroke.

[Means for solving problems]

The characteristic configuration of the turn control device for an automatic traveling work vehicle according to the present invention is such that the turning control means is configured to control when the turning angle from one working stroke to the next working stroke in a direction intersecting with the working stroke is larger than a set angle. The large turn control means includes a large turn control means that controls turning, and a small turn control means that controls turning when the turning angle is smaller than a set angle, and the large turn control means controls the large turn control means based on the stored information of the turning angle. and a turning pattern switching means for selectively switching the small turning control means into an operating state,
Its actions and effects are as follows.

[For production]

A large swing control means that can efficiently turn the swing control means when the swing angle from one work stroke to the next work stroke is large, and a small swing control means that can efficiently turn the swing control means when the swing angle from one work stroke to the next work stroke is large. The large turning control means and the small turning control means are switched and used depending on the turning angle.

〔Effect of the invention〕

Therefore, the turning control means is switched between large turning and small turning depending on the turning angle from one working stroke to the next working stroke that intersects with that working stroke, so regardless of the magnitude of the turning angle, Turns can be made efficiently, which is advantageous in improving work efficiency.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Figures 2 and 3, a pair of left and right front wheels (IF
) and a rear wheel (IR), both of which can be steered freely and are simultaneously driven by an engine (E), are provided in the lower abdomen of the vehicle body (V), and a rear wheel (IR) is provided in the lower abdomen of the vehicle body (V). A lawn mowing device (2) driven by the mower is suspended vertically and movably, thereby forming a work vehicle used for mowing grass and weeds.

In the figure, (3) is a seat for boarding, and 01) is a steering handle for boarding operation.

The work vehicle has a vehicle body (V) on the unmown land (B) side and the mowed land (C) side with respect to the boundary (L) between the unmown land (B) and the mowed land (C). Four sets of a pair of copying sensors (st) and (sz) for detecting which side the lawn mower has deviated from are extended in both front and rear directions from both ends of the lawn mower f (2). The sensor support frame (4) is supported by the tip of the sensor support frame (4). However, of the four sets of copying sensors (Sl), C5Z"), two sets located on the front side of the vehicle body are used when the vehicle body moves forward, and two sets located on the rear side of the vehicle body are used when the vehicle body moves backwards. The vehicle is designed to be able to travel automatically in either forward or backward motion with no difference.

The work vehicle is also equipped with the following sensors.

In other words, in order to detect deviations from a reference direction that is preset based on the length direction of the work process as information indicating the direction of the work process, the orientation of the vehicle body (V) is determined as an absolute direction by sensing the geomagnetic field. A direction sensor (S,) using a geomagnetic sensor for detection is provided on the upper part of the vehicle body on the rear end side of the seat (3).

Furthermore, in order to detect the running path MC1> of the vehicle body (V), a distance sensor (S4) that outputs a predetermined number of pulse signals per unit traveling distance is connected to a driven wheel ( 5) is provided so as to be rotationally driven.

The configuration of the pair of copying sensors (Sl) and (Sz) and the detection of lateral deviation by these sensors (Sl,) (SZ) will be explained below.
The end faces of a pair of optical fibers extending from each of the light emitting element and the light receiving element provided on the sides are arranged so as to face each other with a predetermined interval, and each of the sensors (Sυ, (SZ)) It is configured as a so-called photointerrupter type optical sensor.

Therefore, each copying sensor (st), (st) is shielded from light by the grass when it is located on the uncut land (B).

However, since the detection signals obtained from the tracing sensors (Sl) and (St) become discontinuous pulse-like signals because the grass passes intermittently between the pair of optical fibers, After processing, the level "H" indicates the detection state of the unmowed ground (B), and the level "L" indicates the detection state of the mowed ground (C).
``It is designed to convert into a logical signal indicating each detection state of the level.

These sensors (Sl) and (Sr) are arranged side by side in the direction of the vehicle body, and the deviation state with respect to the work process is determined based on the detection information of these sensors (st) and (sz).

In other words, of the pair of copying sensors (S+) and (SZ), the copying sensor (Sl) is located on the outside with respect to the vehicle body (V).
The state in which the output of the inner copy sensor (S2) is at the "L" level and the output of the inner copying sensor (S2) is at the "H" level is considered to be the state in which the vehicle body (V) is at the boundary (L), that is, in an appropriate state for the work process. If the outputs of the pair of scanning sensors (S+) and (SZ) are both at the "°H°" level, the vehicle body (V) is aligned with the boundary (L). If it is determined that the vehicle body (V) has deviated to the unmowed land (B) side, and the outputs of the pair of copying sensors (S+) and (SZ) are both at the “L” level, the vehicle body (V) is moving toward the boundary. It is determined that the area is shifted toward the mown area (C) with respect to the area (L).

To explain the structure of the vehicle body (V), as shown in FIG. 1, the pair of left and right front wheels (IF) and rear wheels (IR
) for steering hydraulic cylinders (6F) that operate each of them separately.
), (6R) and its control valve (7F),
(7R) is provided.

A hydraulic continuously variable transmission (8) capable of freely switching between forward and reverse directions and variable speed in both forward and backward directions is interlocked and connected to the engine (E), and includes a speed change pedal (9) and a speed change motor (10) for on-board operation. However, with any of these, the speed can be changed freely.
The transmission arm (11) of the transmission (8) is interlocked with the transmission arm (11).

Next, a control configuration for steering and shifting in each of automatic driving and boarding operation will be described.

As shown in FIG. 1, a control device (12) using a microcomputer is provided, and based on commands from this control device (12), the steering hydraulic cylinders (6F), (
The basic configuration is to operate the control valves (7F), (7R) of the control valves (7F), (7R), and the speed change motor (10), and during automatic driving, each of the sensors (Sl) to ( a steering control means for steering the vehicle to automatically travel along the work process, that is, the boundary (L) based on the detection information of step S4); A turning control means (100) is configured using the control device (12), and during boarding maneuvering, the turning control means (100) is configured to perform steering based on steering instruction information from the steering handle (H). A steering means for directing the vehicle will also be configured using the control device (12).

In order to configure these means, the handle (
Potentiometer (Ro) for detecting the target steering position that detects the target steering position during boarding maneuver by detecting the operation position of 1), and a potentiometer (Ro) for detecting the steering position of the front wheels that detects the steering position of the front wheels (IF). potentiometer (R1), said rear wheel (IR)
a rear wheel steering position detection potentiometer (R2) that detects the steering position of the rear wheels; and a shift state detection potentiometer (R2) that detects the position of the shift arm (11), that is, the operating state of the transmission (8). R
The respective detection signals of 3) are input to the control device (12).

In the figure, (13) is a reaping type instructing switch for instructing the control device (12) as to the reaping type, which will be described in detail later.

By the way, since the front and rear wheels (IF) and (IR) are configured to be able to be steered freely, there is a parallel steering type in which the front and rear wheels (IF) and (IR) are turned in the same direction. It is possible to select between a four-wheel steering type that changes the direction in the opposite direction and makes a sharp turn, and a two-wheel steering type that changes the direction of only the front wheels (IF). And during boarding maneuvers,
Any of the three types of steering types can be selected, and during automatic driving, the parallel steering type and the four-wheel steering type are automatically selected for steering.

Next, an outline of how the vehicle moves during automatic driving will be explained.

As shown in Fig. 4, in order to form the planned work area of uncut land (B) into a rectangular shape surrounded by already cut land (C),
The distance sensor (S4) travels around the outer periphery of the scheduled work area while mowing the lawn by manual operation in advance, and measures the reference distance of each side along the outer periphery of the scheduled work area.
At the same time, a reference direction indicating the orientation of each side is detected based on the detection information of the direction sensor (S3), and the reference information is
This will be stored in advance in the control device (12) (hereinafter referred to as a teaching process).

During automatic driving, the vehicle automatically travels around the unmoved area (B) while performing turn control to turn towards the next working process every time it reaches the end of each working process. This allows mowing work to be carried out in a so-called circular mowing format.

However, in this embodiment, as one work stroke is completed, the next work stroke adjacent to it is run in a parallel state by switching forward and backward, so that the work is performed using a so-called forward and backward mowing method. It is configured so that it can also be done.

Therefore, before starting automatic driving, it is recommended to instruct in advance whether to perform the work in the circular mowing style or the forward and backward mowing style using the mowing style instructing switch (13). Then, based on the instruction information, a turn pattern to be used is automatically selected in the turn control described later, and the vehicle is automatically driven.

An explanation will be given below while describing the operation of the control device (12).

As shown in FIG. 5, when the control is started, it is first determined whether to perform the above-mentioned teaching process or to start automatic driving based on the information set in the teaching process.

If it is not a teaching process, the reaping format is set based on the information of the reaping format instruction switch (13), and then, as the travel start command is input, the reaping speed is set to a preset predetermined travel speed. , the variable speed motor (10)
Activate and start driving.

After the start of driving, the vehicle body (
By determining whether or not the orientation of V) is within the set tolerance, it is determined whether there is a deviation in the orientation of the vehicle body relative to the work process. If the orientation of the vehicle body is deviated, direction control is performed to correct the orientation of the vehicle body by performing a steering operation using the four-wheel steering method.

Next, on the front side with respect to the traveling direction and at the boundary (L
A pair of scanning sensors (St) located on the ) side.

Based on the detection information of (St), it is determined whether there is a positional shift in the vehicle body width direction with respect to the boundary (L). If the vehicle body position is deviated, the position in the width direction relative to the boundary (L) is corrected without changing the direction of the vehicle body (V) by performing a steering operation using the parallel steering method.

Accordingly, the orientation control process corrects the orientation of the vehicle body (V) based on the detection information of the orientation sensor (S,), and the orientation control process that corrects the orientation of the vehicle body (V) based on the detection information of the copying sensors (St), (St). The steering control means is constituted by the following control processing for correcting the position of the steering wheel.

As will be described in detail later, the distance sensor (S4)
and an unused copying sensor (St) located on the front side with respect to the traveling direction and on the uncut land (B) side with respect to the boundary (L).

(St) to determine whether or not the turn condition determined based on the detection result of the grass density state is satisfied;
It is determined whether or not to turn the vehicle body (V) toward the next work process. If the turn condition is not satisfied, the direction sensor (S, ) and copying sensor (St), (St)
The steering control process is repeated based on the detected information. However, if the number of working strokes set based on the length of the working stroke set in the teaching process and the working width of the lawn mowing device (2) is reached, the work is finished and the vehicle body (V ) will be stopped.

To explain the process of determining whether or not the turn condition is satisfied, as shown in FIG. 4, the distance sensor (S
4) Detection pressure ii! 1 (1) is the lower limit distance (βI) of the turn permission distance obtained by subtracting a predetermined distance from the reference distance of one work process, and the upper limit distance obtained by adding the predetermined distance!
(j?z) and is located on the front side in the direction of travel.The mown area (C) is detected by a total of 4 copying sensors (Sυ, (5g), 2 sets on the left and right). As the frequency of the detection state becomes equal to or higher than a set threshold value, it is determined that the turn condition is satisfied.

To explain the process of determining whether the turn condition is satisfied using the four scanning sensors (Sl) and (St) on the traveling direction side, the lower limit distance (11
), a sampling section of the work area condition is set in advance at a location on the near side of
, (s,) is repeatedly sampled, and a value at which the detection frequency of the "L" level, which is a dazed state, is 50% or more is set as the darkness value. Then, as the traveling distance (j) becomes equal to or greater than the lower limit distance (11) of the turn permission distance, the frequency at which the "L 11 level is detected by the four copying sensors (Sl), C5t> becomes as follows. As the darkness value exceeds the set value, it is determined that the turn condition has been met.

However, if the above turn conditions are not met,
If the traveling distance (A') has reached the upper limit value (12), it is assumed that the turn condition has been determined incorrectly, and the vehicle is forced to turn.

Next, the turn control as the turning side <n means (100) will be described in detail.

As shown in FIG. 6, as the turn control is activated, it is determined whether the set mowing style is a circular mowing style or a forward and backward mowing style.

In the case of round-cutting, the difference between the reference direction (α) of the next work stroke and the reference direction (β) of the current work stroke, which was set and stored in advance in the teaching process, that is,
Calculate the absolute value (θ) of the turning angle (α-β) from one work stroke to the next work stroke that intersects with that work stroke, and determine whether the absolute value (θ) is the set angle (set to 120 degrees). be)
It is determined whether or not there are more than or equal to the number. If the angle is less than the set angle, the turn is performed by the process (RTURN) as the small turn control means (100B), which will be described later.
The turning pattern of the turn control is automatically switched and controlled so that the turn is made in the processing of (UTURN) as 0A). Therefore, in the process described above,
Based on the stored information on the turning angle, the large turning control means (10
Turn pattern switching means (101) for selectively switching the operating state between the small turn control means (100B) and the small turn control means (100B);
is configured, and the swing control means (1
00) is composed of a large turning control means (100A) and a small turning control means (100B).

On the other hand, when the reaping type is forward and backward mowing, the (Z
TURN) processing will be performed.

Next, each turn process will be explained in detail.

To explain the above-mentioned (RTURN) processing, as shown in FIG. 8, even after one work process is completed, the first set distance (Rβ1 ), and then, while maintaining the steering angle at the preset setting amount (it is set to the important angle) and using 4-wheel steering, move the mowed land on the side away from the next work process. (C) direction, turn the second set distance (R1g) in a backward state, and then move straight forward toward the starting end of the next work stroke.
The turning pattern is preset and stored in a standardized state. However, each of the first set distance (Rlt) and the second set distance (Rlz) is adjusted so that each of the first set distance (Rlt) and the second set distance (Rlz) has an appropriate value according to the size of the angular difference (α-β). β)
Each distance is set and stored in a table in advance, with the absolute value (θ) corresponding to each of the angle ranges divided into a plurality of stages.

That is, as shown in FIG. 7, as the (RTURN) process is started, the first set distance (Rz+) and second set distance (Rtt
After reading each of z), the front and rear wheels (IF),
(IR) are maintained in a straight traveling state, and after advancing the first set distance (Rf+), the vehicle is temporarily stopped.

Next, the transmission (8) is switched to the reverse side, and the second set distance (Rffit) is moved backwards to the mown area (C) at the maximum turning angle and in the four-wheel steering mode. Turn in the direction and then stop.

Then, after returning both the front and rear wheels (IF) and (IR) to the steering neutral state in which the vehicle is moving straight, the vehicle is switched to a forward state and the vehicle is moved toward the starting end of the next working stroke.

To explain the above (UTURN) processing, the 10th
As shown in the figure, as one work process is completed,
While the steering angle is maintained at a preset setting amount (set to the maximum turning angle) and in a four-wheel steering mode, the first set distance (Ul+) is set while moving forward toward the next work stroke side. After turning, the second set distance (U j
! t) straight ahead and backward, and with the steering angle maintained at the preset amount (set to the maximum turning angle) and with the 4-wheel steering type 2, from the start of the next work stroke. A turning pattern is set and stored in advance so that the robot turns a third set distance (OI!) in a reverse state toward the leaving side and then moves forward in a straight state toward the starting end of the next working stroke. However, the first set distance (U
β1), the second set distance (01z), and the third set distance (u i z) are adjusted so that the angle Difference (α−β
) is made to correspond to each of the angular ranges divided into a plurality of stages, and each distance is set and stored in a table in advance.

That is, as shown in FIG. 9, as the process of (UTURN) is started, the first setting distance (ug+) and second setting distance (utt
t) and the third set distance (U l 3), move forward in the direction parallel to the next working stroke at a preset steering angle and in a four-wheel steering mode. After turning the first set distance (Ul+), the robot is once stopped.

Next, the transmission (8) is switched to the reverse side, and the second set distance (Ul) is moved straight backward.Furthermore, the third set distance (Ul1ff) is set at the preset steering angle. In addition, with four-wheel steering, the machine is turned in a backward state in a direction away from the starting end of the next working stroke, and then stopped.

Then, after returning both the front and rear wheels (IF) and (IR) to the steering neutral state in which the vehicle is moving straight, the vehicle is switched to a forward state and the vehicle is moved toward the starting end of the next working stroke.

To explain the above-mentioned (ZTURN) for forward and backward movement, as shown in FIG. 12, as one work stroke is completed, a set distance ( After the ZZt) is moved in parallel, it is switched between forward and backward movement, and is caused to advance straight toward the starting end of the next work stroke.

That is, as shown in FIG. 11, by determining whether the current number of work strokes is an odd number or an even number, it is possible to determine whether the next work stroke is located to the left or right of the current work stroke. Determine.

Then, after moving the set distance (21+) in parallel in the determined direction using a parallel steering method,
Return the steering wheel to neutral and stop the vehicle.

Next, in the same way as above, by determining whether the number of work strokes is an odd number or an even number, it is set whether the next work stroke is to be run in reverse or forward. , start running.

However, in this (ZTURN) processing, the work strokes are set in parallel to each other, and since the vehicle body (ν) is moved in parallel, the above (RTURN)
) and (UTURN), there is no need to consider the turning angle for the next working stroke, and therefore the setting distance (ZII) for parallel movement toward the next working stroke can be set to a constant value. be.

[Another example]

In the above embodiment, in each turning pattern, the vehicle body (V)
While maintaining the steering amount at the maximum turning angle when turning,
By changing each setting distance according to the turning angle,
Although the case where the vehicle is adapted to different turning angles has been exemplified, for example, the set distance traveled may be kept constant, and the turning radius may be changed by changing the amount of steering depending on the turning angle.

Further, in the above embodiment, the (UTURN) serving as the large turning control means (100A) turns the first set distance (IJJ+) toward the next working stroke side, as shown in FIG. After moving straight backward for the set distance (U l g>), turn the third set distance (U 13) in reverse to the side away from the next work stroke, and move straight ahead toward the next work stroke. As shown in Fig. 13, after turning the first set distance (UAυ toward the next work stroke side), the second set distance (01g) is moved straight backwards. After that, the robot may be turned in the forward state by a third set distance (UJ3) to enter the next work stroke.

In addition, in the above embodiment, the case where the turning patterns were different for [RTURN]' for small turns and (UTURN) for large turns was illustrated, but as shown in FIG. 14, the same turning pattern The turning radius may be changed to large or small while using the turning radius, and the turning distance may be set to be large or small depending on the turning angle.
) and the small turning control means (100B) are as follows:
Various changes can be made.

In addition, in the above embodiment, the reference orientation of each work stroke is set to
Although we have exemplified a case in which the teaching process automatically memorizes information, it is also possible to artificially enter information on the reference direction and turning angle into the control device (12) in advance before starting automatic travel. You may also set it. In addition, the reference orientation of each work process is automatically updated by using the information detected by the orientation sensor (S3) during each work process, so that each work that changes as the actual work progresses. In response to a change in the direction of the stroke, the storage information of the turning angle that is set and stored before the start of work may be automatically updated, and the specific configuration of the means for setting and storing the turning angle information can be changed in various ways.

In addition, in the above embodiment, in order to automatically travel along the work process, a copying sensor (Sυ, (SZ)) and a direction sensor (Sυ) are used.
, ) has been exemplified, but the control configuration for automatically driving along the work process may be changed depending on the configuration of the work vehicle to which the present invention is applied. Yes, the specific configuration of each part of the work vehicle can be changed in various ways.

Incidentally, in order to facilitate comparison with the drawings, reference numerals are written in the claims, but the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

The drawings show an embodiment of the turn control device for an automatic traveling work vehicle according to the present invention, FIG. 1 is a block diagram showing the control configuration, FIG. 2 is an overall side view of the work vehicle, and FIG. 3 is a plan view thereof. Fig. 4 is an explanatory diagram of the work area, Fig. 5 is a flowchart showing the outline of the operation of the control device, Fig. 6 is a flowchart showing the turn pattern switching operation, and Fig. 7 is a flowchart showing the control operation of the small turning control means. , FIG. 8 is an explanatory diagram of the turn pattern, FIG. 9 is a flowchart showing the control operation of the large turning control means, FIG. 10 is an explanatory diagram of the turn pattern, and FIG. 12 is an explanatory diagram of the turn pattern, FIG. 13 is an explanatory diagram showing another embodiment of the turn pattern in a large turn, and FIG. 14 is an explanatory diagram showing another embodiment of each large and small turn pattern. (100)...Turning control means, (100A)
...Large turning control means, (100B)...
Small turning control means, (101)...turning pattern switching means, (α-β)...turning angle.

Claims (1)

[Scope of Claims] 1. An automatic traveling work vehicle equipped with a turning control means (100) that turns the work vehicle toward the next work step that intersects with the completion of one work step. In the turn control device, the turning control means (100) is configured to control a turning angle (α−β) from one working stroke to the next working stroke in a direction intersecting with the turning angle when the turning angle (α−β) is larger than a set angle. It is composed of a large turning control means (100A) that controls turning, and a small turning control means (100B) that controls turning when the turning angle (α-β) is smaller than a set angle, and the turning angle ( an automatic turning pattern switching means (101) for selectively switching the large turning control means (100A) and the small turning control means (100B) into an operating state based on the stored information of α-β). Turn control device for traveling work vehicles. 2. The large turning control means (100A) is configured to turn the working vehicle in a direction along the next working stroke after one working stroke is completed, and then turn the working vehicle in a direction away from the starting end of the next working stroke. Claim 1 The invention is configured to be configured to be rotated and run toward the starting end of the next working stroke.
A turn control device for an automated driving work vehicle as described in 2. 3. The small turning control means (100B) is configured to cause the working vehicle to travel in the direction along the working stroke even after one working stroke is completed, and then to move the vehicle toward the side away from the starting end of the next working stroke. Claim 1 The invention is configured to be configured to be rotated and run toward the starting end of the next working stroke.
A turn control device for an automated driving work vehicle as described in 2.