JP2024057293A - Work vehicle control device and work vehicle control method - Google Patents

Abstract

To make it possible to improve work efficiency by preventing a work machine from frequently stopping as an operator approaches to a work vehicle while securing sufficient safety.SOLUTION: A work vehicle controller includes: a state change detection part 11 detecting state change regarding a distance from a work vehicle 100 or a relative position with respect to an operator 200 working behind the work vehicle 100; and a travel speed control part 12 which controls travel speed of the work vehicle 100 in accordance with the detected state change. When the operator 200 approaches to a contact hazard area 301 (an area to stop a work machine), the work vehicle controller increases travel speed to cause the work vehicle 100 to move away from the operator 200, so as to enable preventing a contact accident between the operator 200 and the work vehicle 100 without widening the contact hazard area 301, as well as, so as to enable preventing the work machine from frequently stopping as the operator 200 enters the contact hazard area 301.SELECTED DRAWING: Figure 3

Description

The present invention relates to a work vehicle control device and a work vehicle control method, and is particularly suitable for use in a device and method that controls the travel and operation of a work vehicle equipped with a work machine at the rear when the work vehicle is automatically driven along a target route.

In recent years, with the decline in the farming population, there is a demand for highly productive agricultural techniques. In response to this, for example, autonomous vehicles (hereafter referred to as robots) that perform specific tasks while autonomously driving are being developed and spread. In addition to agricultural tasks that are performed solely by robots, there are also tasks that are performed in collaboration between robots and humans. One example of the latter is when a robot digs up crops and then a worker picks them up.

When a worker works in cooperation with a robot in the vicinity of the robot, there is a possibility that a contact accident will occur if the worker gets too close to the robot. For this reason, it is necessary to equip the robot with a safety function that detects when a worker approaches an area within a specified distance of the robot (hereinafter referred to as the contact danger area) and stops the work machine. Here, the size of the contact danger area can be said to be one of the important issues from the standpoint of safety and work efficiency.

However, if the contact danger area is widened from the standpoint of prioritizing safety, the work machine will frequently stop due to workers getting too close to the robot, reducing work efficiency. In addition, if the robot and worker are too far apart, it will be difficult for the worker to check the robot's operation, and there will be a problem of reduced work efficiency if there is a delay in checking the robot's malfunction or work error. On the other hand, if the contact danger area is narrowed from the standpoint of prioritizing work efficiency, there is a risk that sufficient safety will not be guaranteed.

A safety system is known that improves the work efficiency of work vehicles by preventing excessive warnings while improving safety for people other than specific workers (see, for example, Patent Document 1). The safety system described in Patent Document 1 identifies specific workers (safety-educated workers with a high level of safety awareness) working within a warning area around the work vehicle, sets these identified specific workers as not subject to warnings, and warns the driver of the work vehicle when a person who is subject to a warning (a worker with a low level of safety awareness or a visitor) is detected within the warning area.

By using the safety system described in Patent Document 1, when a worker or visitor with low safety awareness enters the warning area, the driver of the work vehicle is warned, and it becomes possible to take risk avoidance measures such as having the driver manually stop the work equipment. However, if the warning area is widened with an emphasis on safety, warnings may be issued frequently, which may reduce work efficiency. On the other hand, if the warning area is narrowed with an emphasis on work efficiency, there is a risk that sufficient safety will not be guaranteed. Furthermore, the safety system described in Patent Document 1 does not issue warnings to workers with high safety awareness, so it is not possible to prevent contact accidents caused by safety-conscious workers getting too close to the work vehicle.

JP 2020-125171 A

The present invention was made to solve the problems described above, and aims to improve work efficiency by preventing the work machine from frequently stopping due to the worker approaching the work vehicle while ensuring sufficient safety.

To solve the above problems, the present invention detects changes in the distance or relative position of a worker working behind a work vehicle from the work vehicle, and controls the travel speed of the work vehicle in response to the detected changes in state.

According to the present invention configured as described above, when a worker approaches a dangerous contact area (an area in which the work machine is stopped when the worker enters), the travel speed can be controlled so that the work vehicle moves away from the worker. This makes it possible to prevent the occurrence of a contact accident caused by a worker getting too close to the work vehicle without widening the dangerous contact area. It is also possible to prevent frequent stops of the work machine caused by a worker entering the dangerous contact area. As a result, according to the present invention, it is possible to improve work efficiency by preventing the work machine from stopping frequently due to a worker approaching the work vehicle while ensuring sufficient safety.

1 is a diagram showing a work vehicle equipped with a work vehicle control device according to a first embodiment and a worker working behind the work vehicle; 1 is a block diagram showing an example of a functional configuration of a work vehicle control device according to a first embodiment; FIG. 2 is a diagram for explaining an example of areas and operations in the first embodiment. FIG. 11 is a diagram showing a modified example of an area in the first embodiment. 13 is a block diagram showing an example of a functional configuration of a work vehicle control device according to a second modified example of the first embodiment. FIG. FIG. 11 is a diagram for explaining an example of areas and operations according to a second modified example of the first embodiment. FIG. 11 is a diagram for explaining an example of areas and operations in the second embodiment. FIG. 11 is a block diagram showing an example of a functional configuration of a work vehicle control device according to a second embodiment. 13 is a block diagram showing an example of a functional configuration of a work vehicle control device according to a second modified example of the second embodiment. FIG. FIG. 13 is a diagram for explaining an example of areas and operations according to a second modified example of the second embodiment. FIG. 13 is a block diagram showing an example of a functional configuration of a work vehicle control device according to a third modified example of the second embodiment. FIG. 13 is a block diagram showing an example of a functional configuration of a work vehicle control device according to a fourth modified example of the second embodiment. FIG. 13 is a diagram for explaining an example of areas and operations according to a fourth modified example of the second embodiment. FIG. 13 is a diagram showing modified areas according to a fourth modified example of the second embodiment. FIG. 11 is a block diagram showing an example of a functional configuration of a work vehicle control device according to a third embodiment. FIG. 13 is a diagram for explaining an operation example according to the third embodiment. 11 is a flowchart showing an example of an operation from the start to the end of a task.

First Embodiment
A first embodiment of the present invention will now be described with reference to the drawings. Fig. 1 is a diagram showing a work vehicle 100 equipped with a work vehicle control device 10 according to the first embodiment, and a worker 200 working behind the work vehicle 100.

As shown in FIG. 1, the work vehicle 100 is equipped with a work implement 102 at the rear of a vehicle body 101, and the work vehicle control device 10, a rear camera 103, and a front camera 104 are mounted on the vehicle body 101. The work performed by the work implement 102 can be any work that is performed in coordination with the work performed by a worker 200 at the rear, and the content of the work is arbitrary. As an example, the work performed by the work implement 102 is harvesting work or sowing work in a farm field.

The rear camera 103 is a camera that photographs the rear of the work vehicle 100, including the area where the worker 200 would normally be present when working. The image captured by the rear camera 103 is supplied to the work vehicle control device 10 and used to detect the distance from the work vehicle 100 to the worker 200 or the relative position of the worker 200 to the work vehicle 100. Note that the rear camera 103 is used as a means for detecting the distance or relative position, but is not limited to this. For example, a laser radar such as LiDAR, a millimeter wave radar, etc. may be used instead of or in addition to the rear camera 103.

The front camera 104 is a camera that captures images in front of the work vehicle 100. Images captured by the front camera 104 are supplied to the work vehicle control device 10 and are used to detect obstacles present in front of the work vehicle 100.

The work vehicle control device 10 controls the travel of the work vehicle 100 when it automatically travels along a target route set in advance in a field, and controls the operation of the work implement 102. For example, the work vehicle control device 10 is equipped with a function for detecting the current position and orientation of the work vehicle 100, and automatically travels the work vehicle 100 along a target route set in advance in a field based on the current position and orientation that are successively detected. The work vehicle control device 10 also controls the operation of the work implement 102 according to the work position on the target route.

In particular, in this embodiment, the work vehicle control device 10 performs a characteristic process of controlling the travel speed of the work vehicle 100 in response to changes in the state of the distance or relative position from the work vehicle 100 of the worker 200 working behind the work vehicle 100. The contents of this characteristic process will be explained in order below.

Figure 2 is a block diagram showing an example of the functional configuration of the work vehicle control device 10 according to the first embodiment. As shown in Figure 2, the work vehicle control device 10 according to the first embodiment has, as its functional configuration, a state change detection unit 11, a traveling speed control unit 12, and an alarm unit 13. Here, only the functional configuration related to the characteristic processing described above is shown, and the functional configuration related to the automatic traveling of the work vehicle 100 and the automatic control of the work machine 102 is not shown. This is the same for each embodiment and each modified example described below.

The functional blocks 11 to 13 shown in FIG. 2 can be configured using either hardware, a DSP (Digital Signal Processor), or software. For example, when configured using software, the functional blocks 11 to 13 are actually configured with a computer's CPU, RAM, ROM, etc., and are realized by the operation of a program stored in a storage medium such as the RAM, ROM, hard disk, or semiconductor memory.

The state change detection unit 11 detects state changes in the distance or relative position from the work vehicle 100 of the worker 200 working behind the work vehicle 100. In this embodiment, the state change detection unit 11 detects state changes in the relative position (hereinafter simply referred to as the "position of the worker 200") of the worker 200 with respect to the work vehicle 100 (strictly speaking, the rear camera 103 mounted on the work vehicle 100). That is, the state change detection unit 11 sequentially detects the position of the worker 200 at predetermined time intervals based on the captured images input from the rear camera 103 at predetermined time intervals, and detects state changes in the position detected at each predetermined time interval.

In this embodiment, the position state refers to the state of where the worker 200 is located in an area described below. A change in the position state means that the area in which the worker 200 is located changes. Figure 3 is a diagram for explaining areas and operation examples in the first embodiment. As shown in Figure 3, in the first embodiment, a contact risk area 301 and a work area 302 are set in order from the side closest to the work vehicle 100. The contact risk area 301 and the work area 302 are rectangular areas set behind the work vehicle 100.

The contact risk area 301 is an area in which the work vehicle control device 10 will stop the work machine 102 when it is detected that the worker 200 has entered, and is set in a range adjacent to the work machine 102. In the example of FIG. 3, the contact risk area 301 is set in a rectangular range that is wider than the width of the work machine 102 and in which the distance from the rear end of the work machine 102 to the rear of the work vehicle 100 is a first distance d1. In the following description, the distance from the work vehicle 100 refers to the distance from the work vehicle 100 to the rear (parallel to the direction of travel).

The work area 302 is an area where it is assumed that the worker 200 can safely work behind the work vehicle 100, and is set farther away than the contact danger area 301. In the example of FIG. 3, the work area 302 is set to be the range of a rectangular area set from the rear end of the work machine 102 to the rear of the work vehicle 100 in a manner wider than the contact danger area 301, excluding the contact danger area 301. In other words, the work area 302 is set farther away than the contact danger area 301 in a manner that surrounds the contact danger area 301.

The work area 302 includes an approach area 302A, a normal area 302S, and a retreat area 302R. In this embodiment, the area of the work area 302 that is farther away than the contact risk area 301 and adjacent to the contact risk area 301 (in the example of FIG. 3, an area where the distance from the work vehicle 100 is equal to or greater than the first distance d1 and less than the second distance d2) is the approach area 302A, the area that is farther away than the approach area 301A and adjacent to the approach area 301A (in the example of FIG. 3, an area where the distance from the work vehicle 100 is equal to or greater than the second distance d2 and less than the third distance d3) is the normal area 302S, and the area farther away from the approach area 302A across the normal area 302S (in the example of FIG. 3, an area where the distance from the work vehicle 100 is equal to or greater than the third distance d3) is the retreat area 302R.

The approach area 302A is an area for detecting that the worker 200 is approaching the contact risk area 301. The normal area 302S is an area in which the worker 200 is assumed to be performing normal work. The retreat area 302R is an area for detecting that the worker 200 is unable to keep up with the work vehicle 100 and is retreating.

Note that, although FIG. 3 shows an example in which the boundaries of the contact risk area 301, approach area 302A, normal area 302S, and retreat area 302R are set in straight lines, this is not limiting. For example, as shown in FIG. 4, the boundaries may be set in the shape of an arc.

The travel speed control unit 12 controls the travel speed of the work vehicle 100 in response to a state change in the relative position detected by the state change detection unit 11. In this embodiment, the travel speed control unit 12 increases the travel speed of the work vehicle 100 when the state change detection unit 11 detects a state change in which the worker 200 changes from being in the normal area 302S to being in the approach area 302A, as shown by the arrow Y1 in FIG. 3. For example, the amount by which the travel speed is increased is set in advance, and the travel speed control unit 12 increases the travel speed of the work vehicle 100 by the amount of the increase.

In addition, in this embodiment, when the state change detection unit 11 detects a state change in which the worker 200 changes from being in the normal area 302S to being in the retreat area 302R, as shown by the arrow Y2 in FIG. 3, the travel speed control unit 12 reduces the travel speed of the work vehicle 100. For example, the amount of reduction in the travel speed is set in advance, and the travel speed control unit 12 reduces the travel speed of the work vehicle 100 by the amount of the reduction.

Here, after changing the travel speed of the work vehicle 100 in response to the worker 200 changing from being in the normal area 302S to being in the approach area 302A or the retreat area 302R, the travel speed control unit 12 maintains the changed travel speed. That is, even if the state change detection unit 11 detects a state change (state change in the opposite direction to the arrow Y1 or state change in the opposite direction to the arrow Y2) in which the worker 200 returns from being in the approach area 302A or the retreat area 302R to being in the normal area 302S after changing the travel speed as described above, the travel speed control unit 12 does not change the travel speed at that time, but maintains the travel speed changed in response to the state change of the arrows Y1 and Y2 as described above.

The notification unit 13 notifies the worker 200 when the travel speed control unit 12 changes the travel speed of the work vehicle 100. For example, when the travel speed control unit 12 increases the travel speed of the work vehicle 100, the notification unit 13 notifies the worker 200 by voice to notify that the travel speed will be increased. In addition to the voice, a lamp or the like may be illuminated in a manner corresponding to the increase in travel speed. Also, when the travel speed control unit 12 decreases the travel speed of the work vehicle 100, the notification unit 13 notifies the worker 200 by voice to notify that the travel speed will be decreased. In addition to the voice, a lamp or the like may be illuminated in a manner corresponding to the decrease in travel speed.

As described above, in the first embodiment, a change in the state of the position of the worker 200 working behind the work vehicle 100 relative to the work vehicle 100 is detected, and the travel speed of the work vehicle is controlled in accordance with the detected state change. Specifically, when the state change detection unit 11 detects a state change in which the worker 200 has entered the approach area 302A, the travel speed control unit 12 increases the travel speed of the work vehicle 100.

According to this embodiment configured as described above, when the worker 200 enters the approach area 302A adjacent to the contact risk area 301, that is, when the worker 200 approaches the contact risk area 301, the traveling speed can be increased so that the work vehicle 100 moves away from the worker 200. Therefore, even if the contact risk area 301 is not widened, it is possible to prevent the occurrence of a contact accident caused by the worker 200 approaching too close to the work vehicle 100. In addition, it is possible to prevent the work machine 102 from frequently stopping due to the worker 200 entering the contact risk area 301. As a result, according to this embodiment, it is possible to improve work efficiency by preventing the work machine 102 from frequently stopping due to the worker 200 approaching the work vehicle 100 while ensuring sufficient safety.

In addition, in this embodiment, when the state change detection unit 11 detects a state change that the worker 200 has entered the retreat area 302R, the travel speed control unit 12 reduces the travel speed of the work vehicle 100. With this configuration, when the work by the worker 200 is delayed relative to the travel speed of the work vehicle 100 and the position of the worker 200 enters the retreat area 302R, the travel speed can be reduced so that the work vehicle 100 does not move any further away from the worker 200. This allows the work by the work machine 102 and the work by the worker 200 to be coordinated in a good state.

In this regard, in this embodiment, after the travel speed of the work vehicle 100 is changed in response to the state changes shown by the arrows Y1 and Y2 in FIG. 3, the travel speed after the change is maintained. This allows the work vehicle 100 to travel at a travel speed that coordinates with the work speed of the worker 200. For example, after the travel speed of the work vehicle 100 is increased by one step in response to the worker 200 entering the approach area 302A, when the worker 200 returns to the normal area 302S and then re-enters the approach area 302A, the travel speed of the work vehicle 100 is increased by another step. If the worker 200 continues to exist in the normal area 302S in this state, the travel speed that has been increased by two steps is maintained as it is. This travel speed can be said to be a speed that coordinates with the work speed of the worker 200, and a travel speed that is easy for the worker 200 to work at is maintained.

Below, we explain some variations related to the first embodiment.

(First Modification)
In the above first embodiment, an example was shown in which a retreat area 302R was set within the work area 302, and the travel speed of the work vehicle 100 was reduced when the worker 200 entered the retreat area 302R, but this processing may be omitted. It is preferable to perform this processing in terms of coordinating the travel speed of the work vehicle 100 with the work speed of the worker 200. However, even if this processing is not performed, it is possible to prevent a contact accident between the work vehicle 100 and the worker 200, and to prevent the work machine 102 from frequently stopping due to the worker 200 entering the contact risk area 301.

(Second Modification)
Fig. 5 is a block diagram showing an example of the functional configuration of a work vehicle control device _10-2 according to a second modified example. In Fig. 5, components with the same reference numerals as those shown in Fig. 2 have the same functions, and therefore repeated explanations will be omitted here. As shown in Fig. 5, the work vehicle control device _10-2 according to the second modified example is equipped with a state change detection unit 11-2, a traveling speed control unit 12-2, and a notification unit 13-2 as functional configurations, instead of the state change detection unit ₁₁ , the traveling speed control unit _12, and the notification unit ₁₃ .

Figure 6 is a diagram for explaining areas and an example of operation according to the second modified example. As shown in Figure 6, in the second modified example, the work area 302 includes an approach area 302A, a normal area 302S, and a retreat area 302R, as well as a work delay area 302L. In the example shown in Figure 6, the retreat area 302R is an area whose distance from the work vehicle 100 is equal to or greater than the third distance d3 and less than the fourth distance d4. The work delay area 302L is an area further away than the retreat area 302R (an area whose distance from the work vehicle 100 is equal to or greater than the fourth distance d4).

The travel speed control unit _12-2 increases the travel speed of the work vehicle 100 when the state change detection unit _11-2 detects a state change in which the worker 200 changes from being in the normal area 302S to being in the approach area 302A, as shown by arrow Y1 in Fig. 6. Also, the travel speed control unit 12 decreases the travel speed of the work vehicle 100 when the state change detection unit 11-2 detects a state change in which the worker 200 changes from being in front of the retreat area 302R within the work area 302 to being in the retreat area 302R, as shown by arrow _Y2 in Fig. 6. The above control is the same as in the first embodiment.

Furthermore, when the state change detection unit _11-2 detects a state change in which the worker 200 changes from being in the retreat area 302R to being in the work delay area 302L, as shown by the arrow Y3 in Fig. 6, the travel speed control unit _12-2 stops the travel of the work vehicle 100 (sets the travel speed of the work vehicle 100 to zero). In other words, if the worker 200 retreats into the work delay area 302L, there is a possibility that a work delay has occurred, so the travel of the work vehicle 100 is stopped. By configuring in this way, when the work by the worker 200 is actually delayed, it becomes possible to stop the work vehicle 100 and resume the travel of the work vehicle 100 after the worker 200 has progressed his work to a certain extent.

The notification unit _13-2 issues a notification when the travel speed control unit _12-2 stops travelling, in addition to when it increases or decreases the travel speed of the work vehicle 100. For example, the notification unit _13-2 issues a voice notification notifying the user that travel will be stopped when the travel speed control unit _12-2 stops travelling of the work vehicle 100. In addition to the voice, a lamp or the like may be illuminated in a manner corresponding to the stoppage of travelling.

Second Embodiment
Next, a second embodiment of the present invention will be described with reference to the drawings. In the above-mentioned first embodiment, an example in which one work area 302 is set has been described. In contrast, in the second embodiment, two work areas are set, one for an expert and one for a beginner. That is, the second embodiment is intended for an expert and a beginner to work together.

Figure 7 is a diagram for explaining areas and operation examples in the second embodiment. As shown in Figure 7, in the second embodiment, a contact risk area 301, an expert work area 303, and a novice work area 304 are set in order from the area closest to the work vehicle 100. The contact risk area 301, the expert work area 303, and the novice work area 304 are rectangular areas set behind the work vehicle 100. Of these, the contact risk area 301 is the same as that shown in Figure 3.

The skilled worker work area 303 is an area where it is assumed that the skilled worker 201 can safely work behind the work vehicle 100, and is set farther away than the contact risk area 301. The skilled worker work area 303 includes a skilled worker approach area 303A, a skilled worker normal area 303S, and a skilled worker retreat area 303R. These are the same as the approach area 302A, normal area 302S, and retreat area 302R shown in Figure 6.

That is, the area adjacent to the contact risk area 301 on the far side of the contact risk area 301 (in the example of FIG. 7, an area where the distance from the work vehicle 100 is equal to or greater than the first distance d1 and less than the second distance d2) is the expert approach area 303A. Also, the area adjacent to the expert approach area 303A on the far side of the contact risk area 301 (in the example of FIG. 7, an area where the distance from the work vehicle 100 is equal to or greater than the second distance d2 and less than the third distance d3) is the expert normal area 303S. Also, the area on the far side separated from the expert approach area 303A by the expert normal area 303S (in the example of FIG. 7, an area where the distance from the work vehicle 100 is equal to or greater than the third distance d3 and less than the fourth distance d4) is the expert retreat area 303R.

The skilled worker approach area 303A is an area for detecting when the skilled worker 201 is approaching the contact risk area 301. The skilled worker normal area 303S is an area where the skilled worker 201 is assumed to be performing normal work. The skilled worker retreat area 303R is an area for detecting when the skilled worker 201 is unable to keep up with the work vehicle 100 and is retreating.

The beginner work area 304 is an area where the novice worker 202 is expected to be able to work safely behind the work vehicle 100, and is set behind the expert work area 303. The beginner work area 304 includes a beginner approach area 304A, a beginner normal area 304S, and a beginner retreat area 304R. In this embodiment, the area of the beginner work area 304 that is adjacent to the expert work area 303 on the farther side than the expert work area 303 (in the example of FIG. 7, an area whose distance from the work vehicle 100 is equal to or greater than the fourth distance d4 and less than the fifth distance d5) is set as the beginner approach area 304A. In addition, the area adjacent to the beginner approach area 304A on the farther side than the beginner approach area 304A (in the example of FIG. 7, an area whose distance from the work vehicle 100 is equal to or greater than the fifth distance d5 and less than the sixth distance d6) is set as the beginner normal area 304S. Additionally, the area farther away from the novice approach area 304A, with the novice normal area 304S in between (in the example of FIG. 7, the area that is at a distance of the sixth distance d6 or more from the work vehicle 100) is designated as the novice retreat area 304R.

The novice approach area 304A is an area for detecting when the novice worker 202 is approaching the expert work area 303. The novice normal area 304S is an area where the novice worker 202 is assumed to be working normally. The novice retreat area 304R is an area for detecting when the novice worker 202 is unable to keep up with the work vehicle 100 and is retreating.

Note that, although FIG. 7 shows an example in which the boundaries of each area are set in a straight line, this is not limiting. For example, the boundaries may be set in an arc shape, as in FIG. 4.

Figure 8 is a block diagram showing an example of the functional configuration of a work vehicle control device 20 according to the second embodiment. The work vehicle control device 20 according to the second embodiment is mounted on a work vehicle 100 in place of the work vehicle control device 10 shown in Figure 1. As shown in Figure 8, the work vehicle control device 20 according to the second embodiment has, as its functional configuration, a state change detection unit 21, a traveling speed control unit 22, and an alarm unit 23.

These functional blocks 21 to 23 can be configured using either hardware, DSP, or software. For example, when configured using software, the functional blocks 21 to 23 are actually configured with a computer's CPU, RAM, ROM, etc., and are realized by the operation of a program stored in a storage medium such as the RAM, ROM, hard disk, or semiconductor memory.

The state change detection unit 21 detects state changes in the distance or relative position from the work vehicle 100 of the skilled worker 201 and the novice worker 202 who are working behind the work vehicle 100. In this embodiment, the state change detection unit 21 detects state changes in the relative positions of the workers 201 and 202 with respect to the work vehicle 100.

The travel speed control unit 22 controls the travel speed of the work vehicle 100 in response to a change in the state of the relative position detected by the state change detection unit 21. In this embodiment, when the state change detection unit 21 detects a state change in which the skilled worker 201 changes from being in the skilled worker normal area 303S to being in the skilled worker approach area 303A, as shown by the arrow Y1 in FIG. 7, or when the state change detection unit 21 detects a state change in which the novice worker 202 changes from being in the beginner normal area 304S to being in the beginner approach area 304A, the travel speed control unit 22 increases the travel speed of the work vehicle 100 by a predetermined increase amount.

In addition, in this embodiment, when the state change detection unit 21 detects a state change in which the experienced worker 201 changes from being in the experienced worker normal area 303S to being in the experienced worker retreat area 303R, as shown by the arrow Y2 in Figure 7, or when the state change detection unit 21 detects a state change in which the novice worker 202 changes from being in the beginner normal area 304S to being in the beginner retreat area 304R, the travel speed control unit 22 reduces the travel speed of the work vehicle 100 by a predetermined reduction amount.

In the second embodiment, since an experienced worker 201 and a novice worker 202 work simultaneously, a state change that causes the work vehicle 100 to increase its travel speed (state change indicated by arrow Y1 in FIG. 7) and a state change that causes the work vehicle 200 to decrease its travel speed (state change indicated by arrow Y2 in FIG. 7) may occur simultaneously. In this case, the travel speed control unit 22 prioritizes increasing the travel speed of the work vehicle 100 from the perspective of placing greater importance on safety.

In addition, when a state change occurs simultaneously in the expert work area 303 and the novice work area 304, the travel speed of the work vehicle 100 may be controlled to prioritize the state change that occurs in the expert work area 303.

Even in this embodiment, after the driving speed control unit 22 changes the driving speed of the work vehicle 100 in response to a change in the state of the skilled worker 201 from being in the skilled worker normal area 303S to being in the skilled worker approach area 303A or the skilled worker retreat area 303R, even if the state change detection unit 21 detects a state change in which the skilled worker 201 returns from being in the skilled worker approach area 303A or the skilled worker retreat area 303R to being in the skilled worker normal area 303S, the driving speed control unit 22 does not change the driving speed at that time and maintains the changed driving speed. Similarly, after changing the driving speed of the work vehicle 100 in response to a change in the state of the novice worker 202 from being in the beginner normal area 304S to being in the beginner approach area 304A or the beginner retreat area 304R, the driving speed control unit 22 maintains the changed driving speed even if the state change detection unit 21 detects a state change in which the novice worker 202 returns from being in the beginner approach area 304A or the beginner retreat area 304R to being in the beginner normal area 304S.

The notification unit 23 notifies the workers 201, 202 when the travel speed control unit 22 changes the travel speed of the work vehicle 100. The operation of this notification unit 23 is similar to the operation of the notification unit 13 described in the first embodiment.

As described above, in the second embodiment, the area adjacent to the contact risk area 301 is set as the skilled worker work area 303, and the beginner work area 304 is set farther away than the skilled worker work area 303, so that the skilled worker 201 works in the skilled worker work area 303 and the novice worker 202 works in the beginner work area 304. Therefore, the novice worker 202 basically works away from the contact risk area 301, so it can be said that there is a low possibility of a contact accident occurring due to the novice worker 202 getting too close to the work vehicle 100. However, when the state change detection unit 21 detects a state change that the novice worker 202 has entered the novice approach area 304A, the position of the novice worker 202 has displaced in a direction approaching the contact risk area 301, so the travel speed control unit 22 increases the travel speed of the work vehicle 100, ensuring a safer state.

As with the first embodiment, when the state change detection unit 21 detects that the skilled worker 201 has entered the skilled worker approach area 303A, the travel speed control unit 22 increases the travel speed of the work vehicle 100. Therefore, when the skilled worker 201 enters the skilled worker approach area 303A adjacent to the contact risk area 301, that is, when the skilled worker 201 approaches the contact risk area 301, the travel speed can be increased so that the work vehicle 100 moves away from the skilled worker 201. Therefore, even if the contact risk area 301 is not widened, it is possible to prevent the occurrence of a contact accident caused by the skilled worker 201 getting too close to the work vehicle 100. In addition, it is possible to prevent frequent stops of the work machine 102 caused by the skilled worker 201 entering the contact risk area 301.

As a result, even in the second embodiment, it is possible to improve work efficiency by preventing the work machine 102 from frequently stopping due to the workers 201, 202 approaching the work vehicle 100 while ensuring sufficient safety.

In addition, in this embodiment, when the state change detection unit 21 detects a state change that the skilled worker 201 has entered the skilled worker retreat area 303R or that the novice worker 202 has entered the beginner retreat area 304R, the travel speed control unit 22 reduces the travel speed of the work vehicle 100. With this configuration, when the work by the workers 201, 202 is delayed relative to the travel speed of the work vehicle 100 and the positions of the workers 201, 202 enter the retreat areas 303R, 304R, the travel speed can be reduced so that the work vehicle 100 does not move any further away from the workers 201, 202. This allows the work by the work machine 102 and the work by the workers 201, 202 to be coordinated in a good state.

Below, we will explain some variations related to the second embodiment. The first to fourth variations described in the first embodiment can also be applied to the second embodiment.

(First Modification)
In the above second embodiment, an example was shown in which retreat areas 303R, 304R were set within the work areas 303, 304, and the travel speed of the work vehicle 100 was reduced when the workers 201, 202 entered the retreat areas 303R, 304R, but this process may be omitted.

(Second Modification)
The modified example in which a work delay area is set can also be applied to the second embodiment. Fig. 9 is a block diagram showing an example of the functional configuration of a work vehicle control device _20-2 according to a second modified example. In Fig. 9, components with the same reference numerals as those shown in Fig. 8 have the same functions, and therefore repeated explanations will be omitted here. As shown in Fig. 9, the work vehicle control device _20-2 according to the second modified example is equipped with a state change detection unit 21-2, a traveling speed control unit 22-2, and a notification unit 23-2 as functional configurations, instead of the state change detection unit ₂₁ , the traveling speed control unit ₂₂ , and the notification unit ₂₃ .

Figure 10 is a diagram for explaining areas and operation examples according to the second modified example. As shown in Figure 10, in the second modified example, the beginner work area 304 includes a work delay area 304L in addition to a beginner approach area 304A, a beginner normal area 304S, and a beginner retreat area 304R. In the example shown in Figure 10, the beginner retreat area 304R is an area whose distance from the work vehicle 100 is equal to or greater than the sixth distance d6 and less than the seventh distance d7. The work delay area 304L is an area further away than the beginner retreat area 304R (an area whose distance from the work vehicle 100 is equal to or greater than the seventh distance d7). In the second modified example, the expert work area 303 is the same as in Figure 7.

10 by the arrow Y1, when the state change detection unit _21-2 detects a state change in which the skilled worker 201 changes from being in the skilled worker normal area 303S to being in the skilled worker approach area 303A, or when the state change detection unit _21-2 detects a state change in which the novice worker 202 changes from being in the novice normal area 304S to being in the novice approach area 304A, the travel speed control unit _22-2 increases the travel speed of the work vehicle 100. This control is similar to that in the second embodiment.

10 by the arrow Y2, when the state change detection unit _21-2 detects a state change in which the skilled worker 201 changes from being in the skilled worker normal area 303S to being in the skilled worker retreat area 303R, or when the state change detection unit _21-2 detects a state change in which the novice worker ₂₀₂ changes from being in the beginner normal area 304S to being in the novice retreat area 304R. This control is also similar to that in the second embodiment.

Furthermore, the travel speed control unit _22-2 stops the travel of the work vehicle 100 (sets the travel speed of the work vehicle 100 to zero) when the state change detection unit _21-2 detects a state change in which the novice worker 202 changes from being in the novice backing up area 304R to being in the delayed work area 304L, as shown by the arrow Y3 in Fig. 10. By configuring in this way, when the work by the novice worker 202 is delayed, it becomes possible to stop the work vehicle 100 and resume travel of the work vehicle 100 after the novice worker 202 has progressed to a certain extent. Note that the travel speed control unit _22-2 also stops the travel of the work vehicle 100 when the experienced worker 201 backs up and enters the delayed work area 304L.

The notification unit _23-2 issues a notification when the traveling speed control unit _22-2 increases or decreases the traveling speed of the work vehicle 100, and also when the work vehicle stops traveling.

(Third Modification)
In the second embodiment, the skilled worker 201 works in the skilled worker work area 303, and the novice worker 202 works in the beginner work area 304. However, the work vehicle control device 20 does not distinguish whether the worker in each work area 303, 304 is the skilled worker 201 or the novice worker 202. Therefore, whether the skilled worker 201 is in the beginner work area 304 or the novice worker 202 is in the skilled worker work area 303, the above-mentioned control is executed in response to changes in the state of the skilled worker 201 and the novice worker 202.

In contrast, in the third modified example, the attribute of the worker is recognized as to whether the worker is an experienced worker 201 or a novice worker 202, and the travel speed of the work vehicle 100 is controlled to reflect the recognized attribute. Figure 11 is a block diagram showing an example of the functional configuration of a work vehicle control device _20-5 according to the third modified example. In this Figure 11, components with the same reference numerals as those shown in Figure 8 have the same functions, so duplicated explanations will be omitted here.

11, the work vehicle control device _20-5 according to the third modified example further includes an attribute recognition unit 25 as a functional configuration. Also, a travel speed control unit _22-5 is provided instead of the travel speed control unit 22. The area according to the third modified example is the same as that in FIG.

The attribute recognition unit 25 recognizes the attributes of the worker working behind the work vehicle 100, whether the worker is an experienced worker 201 or a novice worker 202. For example, before starting work, the experienced worker 201 and the novice worker 202 are photographed by the front camera 104 or the rear camera 103, and attribute information is added to the photographed image and stored in the work vehicle control device 20. After starting work, the attribute recognition unit 25 analyzes the photographed image taken by the rear camera 103 and compares the characteristics of the worker in each work area 303, 304 with the characteristics of the worker in the photographed image stored in advance, thereby recognizing the attributes of the worker in each work area 303, 304, whether the worker is an experienced worker 201 or a novice worker 202. Note that instead of analyzing the photographed images by the cameras 103, 104, the attributes of the workers 201, 202 may be recognized based on attribute information transmitted from an electromagnetic storage medium such as an RFID carried by the workers 201, 202.

The travel speed control unit _22-5 controls the travel speed of the work vehicle 100 when a worker recognized by the attribute recognition unit 25 to be a skilled worker 201 is in the skilled worker work area 303, and controls the travel speed of the work vehicle 100 when a worker recognized by the attribute recognition unit 25 to be a novice worker 202 is in the beginner work area 304. When the skilled worker 201 is in the novice work area 304 and when the novice worker 202 is in the skilled worker work area 303, the travel speed control unit _22-5 does not control the travel speed of the work vehicle 100.

When configured in this way, for example, after the skilled worker 201 retreats to the beginner work area 304 (at this time, the traveling speed decreases as the skilled worker passes through the skilled worker retreat area 303R), the traveling speed does not change when returning to the skilled worker work area 303. Similarly, after the novice worker 202 advances to the skilled worker work area 303 (at this time, the traveling speed increases as the novice worker passes through the novice approach area 304A), the traveling speed does not change when returning to the novice work area 304.

Note that this control of not changing the travel speed when the workers 201, 202 return to the original work area 303, 304 can be performed even without the attribute recognition unit 25. For example, when the state change detection unit 21 detects a state change in which the workers 201, 202 (whether they are skilled workers 201 or novice workers 202) move from a state in the skilled worker work area 303 to a state in the beginner work area 304 and then return from a state in the beginner work area 304 to a state in the skilled worker work area 303, the travel speed control unit 22 shown in FIG. 8 does not change the travel speed of the work vehicle 100 when returning.

In addition, when the state change detection unit 21 detects a state change in which the worker 201, 202 (whether an experienced worker 201 or a novice worker 202) moves from a state in the beginner work area 304 to a state in the expert work area 303 and then returns from a state in the expert work area 303 to a state in the beginner work area 304, the travel speed control unit 22 prevents the travel speed of the work vehicle 100 from being changed when returning.

The third modification can also be applied in combination with the first and second modifications.

(Fourth Modification)
In the fourth modified example as well, the attribute of the workers 201, 202 is recognized as to whether they are skilled workers 201 or novice workers 202. In the fourth modified example, the control content of the travel speed of the work vehicle 100 is changed according to the recognized attribute.

Fig. 12 is a block diagram showing an example of the functional configuration of a work vehicle control device _20-6 according to a fourth modified example. In Fig. 12, components with the same reference numerals as those shown in Fig. 11 have the same functions, and therefore repeated explanations will be omitted here. As shown in Fig. 12, the work vehicle control device _20-6 according to the fourth modified example is equipped with a state change detection unit 21-6 and a traveling speed control unit _22-6 as functional components instead of the state change detection unit ₂₁ and traveling speed control unit _22-5 shown in Fig. 11.

Figure 13 is a diagram for explaining areas and operation examples in the fourth modified example. In the second embodiment and the first to third modified examples, the beginner work area 304 is set behind the expert work area 303, and the two work areas 303, 304 do not overlap with each other. In contrast, in the fourth modified example, as shown in Figure 13, instead of the beginner work area 304, a beginner work area 304' is set, the front part of which overlaps with the expert work area 303. In the fourth modified example, a contact risk area is set for an expert and a beginner, and the beginner contact risk area 301' is set larger than the expert contact risk area 301. Here, "larger" means that the distance to the rear of the work vehicle 100 is increased.

The expert work area 303 is the same as that shown in FIG. 3 (unlike FIG. 7, the rear end of the expert retreat area 303R is not limited to less than the fourth distance d4). The beginner work area 304' has a configuration basically similar to that of the expert work area 303, and is set to surround the beginner's contact risk area 301'. Here, the beginner's contact risk area 301' is set to be larger than the expert's contact risk area 301. In other words, the area up to the beginner's first distance d1' (d1<d1') from the work vehicle 100 is set as the beginner's contact risk area 301'.

In the fourth modified example, the area adjacent to the beginner's contact risk area 301' (in the example of FIG. 13, the area where the distance from the work vehicle 100 is equal to or greater than the beginner's first distance d1' and less than the beginner's second distance d2') is set as the beginner's approach area 304A'. Furthermore, the area adjacent to the beginner's approach area 304A' on the far side of the beginner's approach area 304A' (in the example of FIG. 13, the area where the distance from the work vehicle 100 is equal to or greater than the beginner's second distance d2' and less than the beginner's third distance d3') is set as the beginner's normal area 304S', and the area on the far side separated from the beginner's approach area 304A' across the beginner's normal area 304S' (in the example of FIG. 13, the area where the distance from the work vehicle 100 is equal to or greater than the beginner's third distance d3') is set as the beginner's retreat area 304R'. In the example of FIG. 13, the third distance d3' for beginners is set to the same value as the sixth distance d6 shown in FIG. 7, but it may be set to a value different from the sixth distance d6.

The status change detection unit _21-6 applies the expert work area 303 to the skilled worker 201 recognized by the attribute recognition unit 25, and detects a status change within the expert work area 303. In addition, the status change detection unit _21-6 applies the novice work area 304' to the novice worker 202 recognized by the attribute recognition unit 25, and detects a status change within the novice work area 304'.

The travel speed control unit _22-6 increases the travel speed of the work vehicle 100 when the status change detection unit 21-6 detects a status change in which a worker recognized by the attribute recognition unit 25 to be a skilled worker 201 changes from a state in the skilled worker normal area 303S to a state in the skilled worker approach area 303A, as shown by arrow Y1 in Figure 13, or when the status change detection unit _21-6 detects a status change in which a worker recognized by the attribute recognition unit ₂₅ to be a novice worker 202 changes from a state in the beginner normal area 304S' to a state in the beginner approach area 304A'.

In addition, the travel speed control unit _22-6 reduces the travel speed of the work vehicle 100 when the status change detection unit _{21-6 detects a status change in which a worker recognized by the attribute recognition unit 25 to be an experienced worker 201 changes from a state in the experienced worker normal area 303S to a state in the experienced worker retreat area 303R, as shown by arrow Y2 in Figure 13, or when the status change detection unit 21-6 detects} a status change in which a worker recognized by the attribute recognition unit 25 to be a novice worker 202 changes from a state in the beginner's normal area 304S' to a state in the beginner's retreat area 304R'.

According to the fourth modified example configured as above, the skilled worker normal area 303S and the beginner normal area 304S' are set in an overlapping range, so that the novice worker 202 can work near the skilled worker 201. This allows, for example, the novice worker 202 to work while receiving guidance from the skilled worker 201. In addition, in the fourth modified example, the beginner work area 304' is set to surround the beginner contact danger area 301', but the beginner contact danger area 301' is set larger than the skilled worker contact danger area 301, so that it is possible to suppress the occurrence of an accident in which the novice worker 202 comes into contact with the work vehicle 100. Note that, as shown in FIG. 14, the beginner contact danger area 301' may be set to the same size as the skilled worker contact danger area 301, and the beginner approach area 304A' may be set larger than the skilled worker approach area 303A.

The fourth modified example can also be applied in combination with the first to third modified examples. Here, in the example of setting the work delay area 302L shown in FIG. 10, in addition to setting a work delay area behind the beginner retreat area 304R', a work delay area can also be set behind the expert work area 303.

Third Embodiment
Next, a third embodiment of the present invention will be described with reference to the drawings. In the above-mentioned first and second embodiments, an example has been described in which a change in the state of the worker 200 (201, 202) relative to the work vehicle 100 is detected as a change in the state of the worker 200 (201, 202). In contrast, in the third embodiment, a change in the state of the worker 200 (201, 202) is detected as a change in the state of the distance from the work vehicle 100 to the worker 200 (201, 202).

Figure 15 is a block diagram showing an example of the functional configuration of a work vehicle control device 30 according to the third embodiment. The work vehicle control device 30 according to the third embodiment is mounted on a work vehicle 100 in place of the work vehicle control device 10 shown in Figure 1. In Figure 15, components with the same reference numerals as those shown in Figure 2 have the same functions, so duplicated explanations will be omitted here.

As shown in FIG. 15, the work vehicle control device 30 according to the third embodiment has, as its functional configuration, a state change detection unit 31, a traveling speed control unit 32, and an alarm unit 13. These functional blocks 31, 32, and 13 can be configured using any of hardware, DSP, and software. For example, when configured using software, the functional blocks 31, 32, and 13 are actually configured with a computer's CPU, RAM, ROM, etc., and are realized by the operation of a program stored in a storage medium such as the RAM, ROM, hard disk, or semiconductor memory.

The state change detection unit 31 detects a change in the state of the distance from the work vehicle 100 to the worker 200 working behind the work vehicle 100. As described above, the distance from the work vehicle 100 to the worker 200 is the distance from the work vehicle 100 to the rear. In other words, the distance detected by the state change detection unit 31 is not the distance of a straight line connecting the work vehicle 100 (rear camera 103) and the worker 200, but the distance projected onto a straight line extending rearward from the work vehicle 100 (a straight line parallel to the traveling direction of the work vehicle 100). Note that, although an example of operation such as that shown in FIG. 16 is assumed here, if the contact risk area 301 is a semicircular or elliptical shape as shown in FIG. 4, the distance of a straight line connecting the work vehicle 100 (rear camera 103) and the worker 200 can be used.

The travel speed control unit 32 increases the travel speed of the work vehicle 100 when the state change detection unit 31 detects a state change in which the distance from the work vehicle 100 to the worker 200 changes from a state where the distance is equal to or greater than the predetermined close side distance to a state where the distance is less than the predetermined close side distance. The travel speed control unit 32 also decreases the travel speed of the work vehicle 100 when the state change detection unit 31 detects a state change in which the distance from the work vehicle 100 to the worker 200 changes from a state where the distance is less than the predetermined far side distance, which is greater than the predetermined close side distance, to a state where the distance is equal to or greater than the predetermined far side distance.

Here, the predetermined distance on the close side is the second distance d2 to the rear end of the approach area 302A shown in FIG. 3. That is, the travel speed control unit 32 increases the travel speed of the work vehicle 100 when the distance from the work vehicle 100 to the worker 200 changes from a state in which the distance is equal to or greater than the second distance d2 to a state in which the distance is less than the second distance d2.

The predetermined distance on the separation side is the third distance d3 to the front end of the retreat area 302R shown in FIG. 3. That is, the travel speed control unit 32 reduces the travel speed of the work vehicle 100 when the distance from the work vehicle 100 to the worker 200 changes from less than the third distance d3 to equal to or greater than the third distance d3.

Figure 16 is a diagram for explaining the operation of the travel speed control unit 32 described above. In the third embodiment, it is not necessary to detect the position of the worker 200 (a combination of distance and direction from the work vehicle 100), and it is only necessary to detect the distance of the worker 200, so it is not necessary to set areas. Figure 16 does not show an example of setting areas, but shows an example of the operation of the travel speed control unit 32. Note that each area may be set in a striped pattern as shown in Figure 16 (rather than setting each area to surround the contact risk area, each strip-shaped area may be set parallel to the strip-shaped contact risk area).

The travel speed control unit 32 increases the travel speed of the work vehicle 100 when the distance from the work vehicle 100 to the worker 200 changes from a state in which it is equal to or greater than the second distance d2 to a state in which it is less than the second distance d2, as shown by the arrow Y1 in FIG. 16. The travel speed control unit 32 also decreases the travel speed of the work vehicle 100 when the distance from the work vehicle 100 to the worker 200 changes from a state in which it is less than the third distance d3 to a state in which it is equal to or greater than the third distance d3, as shown by the arrow Y2 in FIG. 16.

Here, an example has been described in which a change in the distance state of the worker 200 is detected instead of a change in the position state of the worker 200, based on the first embodiment, but the present invention is not limited to this. In other words, based on the first to second modified examples of the first embodiment, the second embodiment, or the first to fourth modified examples of the second embodiment, a change in the distance state of the worker 200 may be detected instead of a change in the position state of the worker 200.

For example, based on the second embodiment, when detecting a change in the distance of the worker 200 instead of detecting a change in the position of the worker 200, the travel speed control unit 32 controls the travel speed of the work vehicle 100 assuming that there are multiple close side specified distances and multiple far side specified distances at different positions. In this case, the multiple close side specified distances are, for example, the second distance d2 to the rear end of the expert approach area 303A and the fifth distance d5 to the rear end of the novice approach area 304A shown in FIG. 7. In addition, the multiple far side specified distances are the third distance d3 to the front end of the expert retreat area 303R and the sixth distance d6 to the front end of the novice retreat area 304R shown in FIG. 7.

Alternatively, the multiple approach side specified distances are, for example, the second distance d2 to the rear end of the expert approach area 303A and the second beginner distance d2' to the rear end of the novice approach area 304A' shown in FIG. 13. Also, the multiple distances away are the third distance d3 to the front end of the expert retreat area 303R and the third beginner distance d3' to the front end of the novice retreat area 304R' shown in FIG. 13. In this case, the travel speed control unit 32 changes the control content of the travel speed of the work vehicle 100 depending on whether the attribute recognized by the attribute recognition unit 25 is an experienced worker 201 or a novice worker 202.

Other Embodiments
It may be possible to recognize whether or not the person appearing in the image captured by the rear camera 103 is a worker whose image has been registered in advance, and to control the travel speed of the work vehicle 100 in accordance with a change in state detected for the recognized worker. In this way, it is possible to avoid controlling the travel speed of the work vehicle 100 in accordance with the movement in the captured image of an object or person that is not a worker. Note that instead of analyzing the image captured by the rear camera 103, it may be possible to recognize whether or not the person is a worker whose image has been registered in advance based on information transmitted from an electromagnetic storage medium such as an RFID.

The image captured by the front camera 104 may be analyzed, and if a person or obstacle is detected within a specified distance, the work vehicle 100 may be stopped from traveling. In this way, it is possible to ensure the safety of workers when there are workers ahead or when turning.

The manager may be further recognized as an attribute, and the work vehicle 100 may start traveling only when the presence of the manager in the work area 302 (the skilled worker work area 303 or the novice work area 304, 304') is recognized and the manager issues an instruction to start work. In this way, work can be started safely and appropriately. In this case, the skilled worker 201 may be the manager, or a manager may be set separately from the skilled worker 201.

Figure 17 is a flowchart showing an example of operations from the start to the end of work when an administrator is set. Here, a series of operations will be explained using an example in which control of the start of work by an administrator is applied to the first embodiment. In this case, the work vehicle control device 10 further includes an attribute recognition unit (functional configuration for recognizing the administrator) in addition to the functional configuration shown in Figure 2.

First, the attribute recognition unit determines whether the attribute of the person present in the work area 302 is that of a manager, and determines whether an instruction to start work has been issued by the manager (step S1). If it is determined that the instruction to start work has not come from a manager in the work area 302, the process returns to step S1, and the work vehicle 100 does not start traveling. On the other hand, if it is determined that the instruction to start work has come from a manager in the work area 302, the work vehicle 100 starts automatic traveling, and the process proceeds to step S2 and onwards.

Next, the state change detection unit 11 determines whether or not the worker 200 has entered the contact risk area 301 (step S2). If the state change detection unit 11 detects that the worker 200 has entered the contact risk area 301, the travel speed control unit 12 stops the travel of the work vehicle 100 (step S3). At this time, the operation of the work machine 102 also stops. After that, the process proceeds to step S9.

If the state change detection unit 11 determines in step S2 that the worker 200 has not entered the contact risk area 301, the state change detection unit 11 then determines whether the worker 200 has entered the approach area 302A (step S4). If the state change detection unit 11 detects that the worker 200 has entered the approach area 302A, the travel speed control unit 12 increases the travel speed of the work vehicle 100 (step S5). The process then proceeds to step S9.

If the state change detection unit 11 determines in step S4 above that the worker 200 has not entered the approach area 302A, the state change detection unit 11 then determines whether the worker 200 has entered the retreat area 302R (step S6). If the state change detection unit 11 detects that the worker 200 has entered the retreat area 302R, the travel speed control unit 12 reduces the travel speed of the work vehicle 100 (step S7). The process then proceeds to step S9.

If the state change detection unit 11 determines in step S6 above that the worker 200 has not entered the retreat area 302R, the travel speed control unit 12 maintains the travel speed of the work vehicle 100 (step S8). The process then proceeds to step S9. In step S9, it is determined whether or not the scheduled work has been completed. For example, it is determined whether or not the entire pre-set target route has been traveled. Alternatively, it is determined whether or not an instruction to end the work has been issued by the manager. If it is determined here that the work has not been completed, the process returns to step S2. On the other hand, if it is determined that the work has been completed, the process of the flowchart shown in FIG. 17 is terminated.

In the above embodiment, an example has been described in which the work vehicle control devices 10, 20, 30 are mounted on the work vehicle 100, but the present invention is not limited to this. For example, the above-mentioned functional configuration may be provided in a remote control device installed in a remote base station or the like, and the work vehicle 100 may be provided with a device that receives instructions from the remote control device and controls the travel of the work vehicle 100 and the operation of the work machine 102. In this case, the remote control device receives images captured by the rear camera 103 and generates instruction information for executing control related to the above-mentioned functional configuration. The generated instruction information is then transmitted to an on-board device of the work vehicle 100, causing the operation according to the instruction to be executed.

In addition, each of the embodiments and modifications described above is merely an example of how the present invention can be implemented, and the technical scope of the present invention should not be interpreted in a limiting manner based on them. In other words, the present invention can be implemented in various forms without departing from its gist or main features.

10, 20, 30 Work vehicle control device 11, 21, 31 State change detection unit 12, 22, 32 Travel speed control unit 25 Attribute recognition unit

Claims (23)

A work vehicle control device that performs driving control when automatically driving a work vehicle equipped with a work implement at the rear along a target route,
a state change detection unit that detects a state change in a distance or a relative position from the work vehicle of a worker working behind the work vehicle;
a travel speed control unit which controls the travel speed of the work vehicle in response to a state change detected by the state change detection unit. Set up contact danger areas and work areas in order of proximity to the work vehicle.
Among the above-mentioned work areas, an area adjacent to the above-mentioned contact risk area is defined as an approach area,
2. The work vehicle control device according to claim 1, wherein the travel speed control unit increases the travel speed of the work vehicle when the state change detection unit detects a state change in which the worker changes from a state where the worker is outside the approach area within the work area to a state where the worker is inside the approach area. Among the above-mentioned working areas, an area on the far side of the above-mentioned approach area with a normal area in between is defined as a retreat area,
3. The work vehicle control device according to claim 2, wherein the traveling speed control unit reduces the traveling speed of the work vehicle when the state change detection unit detects a state change in which the worker changes from a state where the worker is outside the reverse area within the work area to a state where the worker is inside the reverse area. Among the above-mentioned work areas, an area on the far side of the approach area across a normal area is defined as a retreat area, and an area on the far side of the retreat area is defined as a work delay area,
3. The work vehicle control device according to claim 2, wherein the travel speed control unit reduces the travel speed of the work vehicle when the state change detection unit detects a change in state from a state in which the worker is in front of the retreat area within the work area to a state in which the worker is within the retreat area, and stops travel of the work vehicle when the state change detection unit detects a change in state from a state in which the worker is in the work area and outside the work delay area to a state in which the worker is within the work delay area. Set up a contact danger area, an expert work area, and a beginner work area in order of proximity to the work vehicle.
Among the skilled worker working areas, an area adjacent to the contact risk area is defined as a skilled worker approach area, and among the novice working areas, an area adjacent to the skilled worker working area is defined as a novice approach area;
The work vehicle control device according to claim 1, characterized in that the travel speed control unit increases the travel speed of the work vehicle when the state change detection unit detects a state change in which the worker changes from a state where the worker is outside the skilled worker approach area within the skilled worker work area to a state where the worker is inside the skilled worker approach area, or when the state change detection unit detects a state change in which the worker changes from a state where the worker is outside the novice approach area within the novice work area to a state where the worker is inside the novice approach area. an area of the skilled worker working area that is farther away from the skilled worker approach area with a skilled worker normal area in between is defined as an skilled worker retreat area, and an area of the novice working area that is farther away from the novice approach area with a novice normal area in between is defined as a novice retreat area,
6. The work vehicle control device according to claim 5, wherein the travel speed control unit reduces the travel speed of the work vehicle when the state change detection unit detects a state change in which the worker changes from a state where the worker is outside the skilled worker retreat area within the skilled worker work area to a state where the worker is inside the skilled worker retreat area, or when the state change detection unit detects a state change in which the worker changes from a state where the worker is outside the novice retreat area within the novice work area to a state where the worker is inside the novice retreat area. Among the expert work areas, an area on the far side separated from the expert approach area by a skilled worker normal area is defined as an expert retreat area, among the novice work areas, an area on the far side separated from the novice approach area by a novice normal area is defined as a novice retreat area, and an area farther than the novice retreat area is defined as a work delay area,
6. The work vehicle control device according to claim 5, wherein the travel speed control unit reduces the travel speed of the work vehicle when the state change detection unit detects a change in state of the worker changing from a state where the worker is outside the skilled worker retreat area within the skilled worker work area to a state where the worker is inside the skilled worker retreat area, or when the state change detection unit detects a change in state of the worker changing from a state where the worker is ahead of the novice retreat area within the novice work area to a state where the worker is inside the novice retreat area, and stops travel of the work vehicle when the state change detection unit detects a change in state of the worker changing from a state where the worker is outside the work delay area to a state where the worker is inside the work delay area. The work vehicle control device according to claim 4, wherein the travel speed control unit changes the travel speed of the work vehicle in response to a change in the state of the worker to being within the skilled worker approach area or the skilled worker retreat area, and maintains the changed travel speed even if the state change detection unit detects a state change in which the worker returns to being outside the skilled worker approach area or outside the skilled worker retreat area, and maintains the changed travel speed even if the state change detection unit detects a state change in which the worker returns to being outside the novice approach area or outside the novice retreat area, after changing the travel speed of the work vehicle in response to a change in the state of the worker to being within the novice approach area or the novice retreat area. An attribute recognition unit that recognizes an attribute of the worker, such as whether the worker is an expert or a novice,
2. The work vehicle control device according to claim 1, wherein the travel speed control unit changes the control content of the travel speed of the work vehicle depending on whether the attribute recognized by the attribute recognition unit is the expert or the novice. The contact danger area and the working area are set for an expert and a beginner, respectively, and the contact danger area for the beginner is set to be larger than the contact danger area for the expert,
an area of the skilled worker work area for the skilled worker that is adjacent to the skilled worker contact risk area is defined as a skilled worker approach area, and an area of the beginner work area for the beginner that is adjacent to the beginner contact risk area is defined as a beginner approach area;
The work vehicle control device according to claim 2 and claim 9, characterized in that the travel speed control unit increases the travel speed of the work vehicle when the state change detection unit detects a state change in which a worker recognized as the expert by the attribute recognition unit changes from a state where the worker is outside the expert approach area within the expert work area to a state where the worker is within the expert approach area, or when the state change detection unit detects a state change in which a worker recognized as the novice by the attribute recognition unit changes from a state where the worker is outside the novice approach area within the novice work area to a state where the worker is within the novice approach area. The contact danger area and the working area are set for an expert and a beginner, respectively, and the contact danger area for the beginner is set to be larger than the contact danger area for the expert,
an area of the skilled worker working area that is farther away from the skilled worker approach area with a skilled worker normal area in between is defined as an skilled worker retreat area, and an area of the novice working area that is farther away from the novice approach area with a novice normal area in between is defined as a novice retreat area,
the travel speed control unit increases the travel speed of the work vehicle when the state change detection unit detects a state change in which the worker recognized as the expert by the attribute recognition unit changes from a state where the worker is outside the expert approach area within the expert work area to a state where the worker is within the expert approach area, or when the state change detection unit detects a state change in which the worker recognized as the novice by the attribute recognition unit changes from a state where the worker is outside the novice approach area within the novice work area to a state where the worker is within the novice approach area,
10. The work vehicle control device according to claim 3 and claim 9, wherein the traveling speed control unit reduces the traveling speed of the work vehicle when the state change detection unit detects a state change in which the worker recognized as the expert by the attribute recognition unit changes from a state where the worker is outside the expert retreat area within the expert work area to a state where the worker is inside the expert retreat area, or when the state change detection unit detects a state change in which the worker recognized as the novice by the attribute recognition unit changes from a state where the worker is outside the novice retreat area within the novice work area to a state where the worker is inside the novice retreat area. The work vehicle control device according to claim 10, characterized in that, instead of setting the contact danger area for an expert and the work area for a beginner, and setting the contact danger area for the beginner larger than the contact danger area for the expert, the approach area for the beginner is set larger than the approach area for the expert. The work vehicle control device according to claim 6 or 7, characterized in that the travel speed control unit prioritizes increasing the travel speed of the work vehicle when a state change that causes an increase in the travel speed of the work vehicle and a state change that causes a decrease in the travel speed of the work vehicle occur simultaneously. An attribute recognition unit that recognizes an attribute of the worker, such as whether the worker is an expert or a novice,
The work vehicle control device according to any one of claims 6 to 8, characterized in that the travel speed control unit controls the travel speed of the work vehicle when a worker recognized as the expert by the attribute recognition unit is in the expert work area, and controls the travel speed of the work vehicle when a worker recognized as the novice by the attribute recognition unit is in the novice work area. The work vehicle control device according to any one of claims 6 to 8, characterized in that when the state change detection unit detects a state change in which the worker returns from being in the novice work area to being in the expert work area after the worker has moved from being in the expert work area to being in the novice work area, the travel speed control unit does not change the travel speed of the work vehicle when returning. The work vehicle control device according to any one of claims 6 to 8, characterized in that when the state change detection unit detects a state change in which the worker returns from being in the skilled worker work area to being in the novice work area after the worker has moved from being in the novice work area to being in the skilled worker work area, the travel speed control unit does not change the travel speed of the work vehicle when returning. The work vehicle control device according to any one of claims 1 to 9, further comprising a notification unit that notifies the worker when the travel speed control unit changes the travel speed of the work vehicle. The work vehicle control device according to claim 1, characterized in that the travel speed control unit increases the travel speed of the work vehicle when the state change detection unit detects a state change in which the distance from the work vehicle to the worker is greater than or equal to a predetermined distance on the close side to a state less than the predetermined distance on the close side. The work vehicle control device according to claim 18, characterized in that the travel speed control unit reduces the travel speed of the work vehicle when the state change detection unit detects a state change in which the distance from the work vehicle to the worker is greater than the close side predetermined distance, that is, less than the close side predetermined distance, to greater than the close side predetermined distance. The work vehicle control device according to claim 18, characterized in that the travel speed control unit controls the travel speed of the work vehicle by assuming that there are multiple close-side predetermined distances at different positions. The work vehicle control device according to claim 19, characterized in that the travel speed control unit controls the travel speed of the work vehicle by assuming that there are multiple close side predetermined distances and multiple far side predetermined distances at different positions. An attribute recognition unit that recognizes an attribute of the worker, such as whether the worker is an expert or a novice,
The work vehicle control device according to any one of claims 18 to 21, characterized in that the travel speed control unit changes the control content of the travel speed of the work vehicle depending on whether the attribute recognized by the attribute recognition unit is the expert or the novice. A work vehicle control method for controlling travel of a work vehicle equipped with a work implement at a rear portion when the work vehicle is automatically travelling along a target route, comprising:
a state change detection unit of a work vehicle control device detecting a state change of a distance or a relative position from the work vehicle of a worker working behind the work vehicle;
a travel speed control unit of the work vehicle control device controlling the travel speed of the work vehicle in response to the state change detected by the state change detection unit.