Work Area Management Method, Work Area Management System, And Work Area Management Program

A work area management method includes storing first area information that represents a first work area that determines a first work route along which a first work device moves to perform a first work in a field, and that is determined on the basis of a positioning position of the first work device. The work area management method also includes outputting the first area information as information that represents an area for determining a second work route along which a second work device different from the first work device moves to perform a second work in the field. The outputting the first area information may include outputting warning information representing that the first area information is unsuitable for determining the second work route when the first area information does not satisfy a predetermined condition.

TECHNICAL FIELD

The present invention relates to a work area management method, a work area management system, and a work area management program.

BACKGROUND ART

In recent years, research has been conducted on work device that performs work in the field by moving autonomously.

Patent document 1 discloses a work device that identifies a work area to be worked on by traveling circumferentially around the work area as a preparatory work before the work by autonomous traveling.

PRIOR ART DOCUMENT

Patent Document

Patent Document 1: Japanese Patent Publication No. 6592367

SUMMARY OF INVENTION

Technical Problem

However, the technology described in Patent Document 1 requires that the work device performing work in the field travels circumferentially around the work area. Therefore, even in the same field, when a different work device is used, it is required to perform preparation work on the work device that performs work.

In view of the above circumstances, one of the objectives of this disclosure is to reduce workload related to preparatory work for work by autonomous traveling by sharing a work area among a plurality of work devices. Other objectives can be understood from the following descriptions and the description of embodiments.

Solution to Problem

A description will hereinafter be given of means for solving the problem with numbers and signs used in embodiments for carrying out the invention. These numbers and signs are added in parentheses as a reference to show an example of corresponding relations between the description of the scope according to claims and the embodiments for carrying out the invention. Therefore, the scope according to claims should not be construed as being limited to the descriptions with the parentheses.

A work area management method according to one embodiment to achieve the above-mentioned objective includes storing first area information that represents a first work area (640) that determines a first work route (650) along which a first work device (100) moves to perform a first work in a field (500), and that is determined on the basis of a positioning position of the first work device (100). The work area management method also includes outputting the first area information as information that represents an area for determining a second work route (750) along which a second work device (300) different from the first work device (100) moves to perform a second work in the field (500).

A work area management system (1000) according to one embodiment to achieve the above-mentioned objective includes an area storage unit (260), and a use area selection unit (270). The area storage unit (260) stores first area information that represents a first work area (640) that determines a first work route (650) along which a first work device (100) moves to perform a first work in a field (500), and that is determined on the basis of a positioning position of the first work device (100). The use area selection unit (270) includes outputting the first area information as information that represents an area for determining a second work route (750) along which a second work device (300) different from the first work device (100) moves to perform a second work in the field (500).

A work area management program (420) that causes a computing device (220) to execute storing first area information that represents a first work area (640) that determines a first work route (650) along which a first work device (100) moves to perform a first work in a field (500), and that is determined on the basis of a positioning position of the first work device (100). The work area management program (420) also causes the computing device (220) to execute outputting the first area information as information that represents an area for determining a second work route (750) along which a second work device (300) different from the first work device (100) moves to perform a second work in the field (500).

Advantageous Effects of Invention

According to the above embodiments, workload related to preparatory work for work by autonomous traveling can be reduced.

DESCRIPTION OF EMBODIMENTS

A description will be made on a work area management system1000according to this embodiment of the present invention with reference to the drawings. As illustrated inFIG.1, the work area management system1000includes a first work device100, a control device200, and a second work device300. The first work device100and the second work device300can move and work autonomously in a field500. The control device200is communicatively connected to the first work device100and the second work device300, and determines work routes along which the first work device100and the second work device300move in the field500.

The first work device100, for example, a tractor, which is steered by an operator, circulates along a contour510of the field500for one time, as illustrated inFIG.2, to register a work area, which represents an area to be worked, in the control device200. For example, the control device200registers, as a work area, an area surrounded by a registration route600that represents the route along which the first work device100circulated and moved, and determines a work route along which the first work device100moves in the registered work area. The first work device100moves in the work area, for example, in the field500, along the determined work route to perform work.

The second work device300, which is different from the first work device100, for example, a combine harvester, also circulates along the contour510of the field500for one time, operated by an operator, as illustrated inFIG.3, to register the work area representing the area to be worked in the control device200. For example, the second work device300follows a first registration route700-1along the contour510to harvest crops grown in the field500. When the second work device300reaches an edge of the field500, the second work device300harvests the crops along a second registration route700-2, which repeatedly moves forward and backward to shift inward in the field500, and secures an area to change a traveling direction. The second work device300then changes the traveling direction and follows a third registration route700-3along the contour510to harvest the crops. Similarly, the second work device300follows a fourth registration route700-4, which repeats forward and backward, a fifth registration route700-5along the contour510, a sixth registration route700-6, which repeats forward and backward, and a seventh registration route700-7along the contour510in turn, thus circulating the field500for one time.

The control device200registers a work area of the second work device300on the basis of the registration route700and determines a work route along which the second work device300moves in the registered work area. The second work device300moves in the work area, for example, in the field500, along the determined work route to perform work.

Thus, the work area in the same field500is registered by both the first work device100and the second work device300. Here, the control device200determines a work route of the second work device300in the work area registered by the first work device100, thereby reducing the work area registration work by a user, for example, an operator. Furthermore, accuracy of the registered work area varies depending on a model of the work device. Therefore, when determining a work route, the control device200may inform the user of a warning depending on the accuracy of the registered work area.

(Configuration of Work Area Management System)

A description will be made on a configuration of the first work device100that is included in the work area management system1000illustrated inFIG.1. The first work device100represents any device that performs work in the field500and includes a tractor that tows a work machine such as a rotary cultivator, a fertilizer, or the like to perform work. The first work device100may include a device that is integrally configured with a work machine, and examples of such a device include a rice transplanter, a combine harvester, and the like. The first work device100may also include a device that flies and performs work, for example, a drone that sprays pesticides.

As illustrated inFIG.4, the first work device100includes a key switch110, a sensor115, a computing device120, a communication device130, and a storage device140. The key switch110generates signals to start and stop an engine of the first work device100. For example, when the key switch110is set to “ON”, the engine of the first work device100is started and a signal representing that the engine has been started is output to the computing device120. When the key switch110is set to “OFF”, the engine of the first work device100is stopped and a signal representing that the engine has been stopped is output to the computing device120. The key switch110may be formed by any switch, as long as the key switch110accepts instructions to start and stop the engine.

The sensor115acquires operation information representing a state of the first work device100. For example, the operation information includes position information representing a position of the first work device100. The sensor115includes a positioning device that measures the position of the first work device100at each time. The positioning device is, for example, a global navigation satellite system (GNSS).

The operation information also includes state information representing the state of the first work device100, such as a speed, steering angle, engine revolution speed, and ON/OFF status of various clutches of the first work device100. For example, in a case where the first work device100is a vehicle that tows a working machine, the state information may include a power take-off (PTO) speed at the time of transmitting power to the working machine, a hitch height and a lift arm angle indicating a posture of the working machine. In this case, the sensor115includes a measurement device that measures each piece of information.

The communication device130communicates with the control device200. The communication device130transfers the information acquired from the control device200to the computing device120. The communication device130transfers signals generated by the computing device120to the control device200. The communication device130includes, for example, a transmitter/receiver used in wireless communication such as a wireless local area network (LAN) and a cellular network, and various interfaces such as a network interface card (NIC) and a universal serial bus (USB).

The storage device140stores various data for controlling the first work device100, for example, a first drive control program400. The storage device140is used as a non-transitory tangible storage medium for storing the first drive control program400. The first drive control program400may be provided as a computer program product recorded on a computer-readable storage medium1, or may be provided as a computer program product that can be downloaded from a server.

The computing device120reads and executes the first drive control program400from the storage device140to perform various data processing to control the first work device100. For example, the computing device120includes a central processing device (CPU; Central Processing Unit), an engine control unit (ECU), and the like.

The computing device120reads and executes the first drive control program400to realize a first drive control unit150, as illustrated inFIG.5. The first drive control unit150controls a speed, traveling direction, etc. of the first work device100so that the first work device100moves along a specified route.

Next, a description will be made on a configuration of the control device200illustrated inFIG.1. As illustrated inFIG.6, the control device200includes an input/output device210, a computing device220, a communication device230, and a storage device240. The control device200includes a computer, a portable terminal such as a tablet. The input/output device210receives information that is used by the computing device220to execute processing. In addition, the input/output device210outputs a result of the processing executed by the computing device220. The input/output device210includes various input devices and various output devices, and examples of the input/output device210are a keyboard, a mouse, a microphone, a display, a speaker, and a touch panel.

The communication device230communicates with a plurality of work devices, for example, the first work device100and the second work device300. The communication device230transfers information acquired from the first work device100or the second work device300to the computing device220. The communication device230also transfers signals generated by the computing device220to the first work device100or the second work device300. The communication device230includes, for example, a transmitter/receiver used in wireless communication such as a wireless local area network (LAN) and a cellular network, and various interfaces such as a network interface card (NIC) and a universal serial bus (USB).

The storage device240stores various data, for example, work area data410and a work area management program420, for determining work routes when a plurality of work devices, for example, the first work device100and the second work device300, perform work. The storage device240is used as a non-transitory tangible storage medium to store the work area management program420. The work area management program420may be provided as a computer program product that is recorded on a computer-readable storage medium2, or may be provided as a computer program product that can be downloaded from a server.

The work area data410stores area information related to a work area where work is performed by a plurality of work devices. For example, as illustrated inFIG.7, the work area data410stores an area position, an area shape, a model of the work device, a registration date, and a final use date for each registered work area. The area position represents a position of the registered work area, for example, a geometric center of the work area. The area shape represents a shape of the registered work area, for example, latitudes and longitudes of the plurality of vertices of a contour of the work area. The area position may be represented by positions of a plurality of vertices of the contour of the work area.

The model of the work device represents a model of the work device used when the work area is registered. For example, when the work area is registered by the first work device100moving along the contour510of the field500, the model of the work device for this work area represents the model of the first work device100, for example, a tractor.

The registration date represents a date when the work area was registered. The final use date represents a final date among dates when a work route was determined using corresponding area information.

The computing device220illustrated inFIG.6reads and executes the work area management program420from the storage device240to perform various data processing to determine the work route of the work device. For example, the computing device220includes a central processing device (CPU; Central Processing Unit) and the like.

By reading and executing the work area management program420, as illustrated inFIG.5, the computing device220realizes an area determination unit250, an area storage unit260, a use area selection unit270, and a route determination unit280. The area determination unit250determines a work area in which a work device performs work on the basis of a measured positioning position of the work device, for example, the first work device100. The area storage unit260stores area information representing the work area determined by the area determination unit250in the work area data410. The use area selection unit270selects area information to be used when determining a work route of a work device, for example, the second work device300. The route determination unit280determines a work route for a work device, for example, the first work device100or the second work device300, to perform work in the field500on the basis of the area information.

Next, a description will be made on a configuration of the second work device300illustrated inFIG.1. The second work device300represents any device that performs work in the field500and differs from the first work device100. The work performed by the second work device300may be different from or the same as the work performed by the first work device100. The second work device300includes a device that is integrally configured with a work machine, and an example of such a device includes a combine harvester. The second work device300may include a rice transplanter. The second work device300may also include a tractor that tows a work machine such as a rotary cultivator, a fertilizer, or the like to perform work. The second work device300may include a device that flies and performs work, for example, a drone that sprays pesticides.

As illustrated inFIG.8, the second work device300includes a key switch310, a sensor315, a computing device320, a communication device330, and a storage device340. The key switch310, similar to the key switch110of the first work device100, generates signals to start and stop an engine of the second work device300. For example, when the key switch310is set to “ON,” the engine of the second work device300is started and a signal representing that the engine has been started is output to the computing device320. When the key switch310is set to “OFF”, the engine of the second work device300is stopped and a signal representing that the engine has been stopped is output to the computing device320. The key switch310may be formed by any switch, as long as the key switch310accepts instructions to start and stop the engine.

The sensor315, similar to the sensor115of the first work device100, acquires operation information representing a state of the second work device300. For example, the operation information includes position information representing a position of the second work device300and state information representing the state of the second work device300.

The communication device330, similar to the communication device130of the first work device100, communicates with the control device200. The communication device330transfers the information acquired from the control device200to the computing device320. In addition, the communication device330transfers signals generated by the computing device320to the control device200.

The storage device340, similar to the storage device140of the first work device100, stores various data for controlling the second work device300, for example, a second drive control program430. The storage device340is used as a non-transitory tangible storage medium for storing the second drive control program430. The second drive control program430may be provided as a computer program product recorded on a computer-readable storage medium3, or may be provided as a computer program product that can be downloaded from a server.

The computing device320, similar to the computing device120of the first work device100, reads and executes the second drive control program430from the storage device340and performs various data processing to control the second work device300. For example, the computing device320includes a central processing device (CPU; Central Processing Unit), an engine control unit (ECU), and the like.

The computing device320reads and executes the second drive control program430to realize a second drive control unit350, as illustrated inFIG.5. The second drive control unit350controls a speed, traveling direction, etc. of the second work device300so that the second work device300moves along a specified route.

(Operation of Work Area Management System)

The work area management system1000controls the first work device100so that the first work device100works autonomously in the field500. For example, when the first work device100performs work in the field500, the user inputs an operation to the input/output device210of the control device200to start work by the first work device100. The computing device220of the control device200reads and executes the work area management program420when an operation by the user is input. When the work area management program420is read and executed, the computing device220starts processing illustrated inFIG.9, which is part of a work area management method.

In step S110, the area determination unit250, which is realized by the computing device220, instructs the operator to move the first work device100by manual steering along a route that makes one round along the contour of the work area, such as the contour510of the field500for one time, as illustrated inFIGS.2and3. The operator steers the first work device100to make the first work device100move along the contour of the work area. The first drive control unit150of the first work device100measures the position of the first work device100at each time and outputs position information representing the measured position at each time to the control device200. The first drive control unit150outputs state information representing a state of the first work device100at each time to the control device200. The area determination unit250of the control device200acquires operation information including the position information and the state information from the first work device100.

In step S120illustrated inFIG.9, the area determination unit250determines a circumferential direction of the first work device100. For example, the area determination unit250determines the circumferential direction of the first work device100on the basis of a steering angle of the first work device100at each time. For example, as illustrated inFIG.2, when the first work device100circulates the work area in a counterclockwise direction, the steering angle of the first work device100is frequently pointing to left. Therefore, the area determination unit250determines the circumferential direction of the first work device100by integrating the steering angles at each time of the first work device100.

In step S130illustrated inFIG.9, the area determination unit250determines an outer edge route610of the first work device100on the basis of the circumferential direction and the position information of the first work device100. The outer edge route610represents a route that an outer edge of the first work device100passes through when the first work device100moves along the registration route600, as illustrated inFIG.10. For example, the area determination unit250stores in advance a left side distance from a position of the positioning device of the first work device100to a left end of the first work device100and a right side distance from the position of the positioning device to a right end of the first work device100in a direction orthogonal to the traveling direction of the first work device100. When the circumferential direction of the first work device100is counterclockwise, the area determination unit250determines a route that is distant from the registration route600by the right side distance to right with respect to the traveling direction of the first work device100as the outer edge route610. When the circumferential direction of the first work device100is clockwise, the area determination unit250determines a route that is distant from the registration route600by the left side distance to left with respect to the traveling direction of the first work device100as the outer edge route610. The left side distance and the right side distance may be determined by adding a predetermined distance from the position of the positioning position to the corresponding end of the first work device100. The registration route600represents, for example, a route connecting the positions of the first work device100with straight line segments in the order of the measured time.

In step S140illustrated inFIG.9, the area determination unit250extracts, from the outer edge route610, the straight line routes along which the first work device100moved in a straight line. The area determination unit250extracts straight line routes by any method. For example, the area determination unit250determines an area that is sandwiched between two straight lines that extend in the traveling direction and pass through the left or right end of the first work device100at the end of the turning travel of the first work device100. When the outer edge route610of the first work device100included in the determined area is longer than a threshold value, the area determination unit250extracts the outer edge route610of the first work device100included in the area as a straight line route.

In step S150, the area determination unit250determines a work area where work is to be performed by the first work device100. For example, as illustrated inFIG.10, the area determination unit250determines approximate straight lines620that approximate the extracted straight line routes. The area determination unit250determines a vertex630where the approximate straight lines620corresponding to two temporally adjacent straight line routes intersect among the determined approximate straight lines620. An intersection of the approximate straight line620corresponding to a temporally last straight line route and the approximate straight line620corresponding to a temporally first straight line route is added to the vertex630. The area determination unit250determines, as a temporary work area, a polygon that has the determined plurality of vertices630as vertices and edges extending onto the approximate straight lines620. The area determination unit250displays information representing the determined temporary work area on the input/output device210to accept a modification operation of the work area by the user. The area determination unit250modifies the work area in response to the modification operation by the user.

For example, the area determination unit250selects a first approximate straight line620-1and a second approximate straight line620-2as approximate straight lines620corresponding to two temporally adjacent straight line routes. The area determination unit250determines a first vertex630-1where the selected first approximate straight line620-1and the second approximate straight line620-2intersect. Similarly, the area determination unit250selects the second approximate straight line620-2and a third approximate straight line620-3, and determines a second vertex630-2where the two selected approximate straight lines620intersect. In addition, the area determination unit250determines a third vertex630-3where the third approximate straight line620-3and a fourth approximate straight line620-4intersect, and a fourth vertex630-4where the fourth approximate straight line620-4and the first approximate straight line620-1intersect. As illustrated inFIG.11, the area determination unit250determines, as a temporary work area, a polygon that has the first vertex630-1, the second vertex630-2, the third vertex630-3, and the fourth vertex630-4as vertices and is surrounded by the approximate straight lines620.

An image representing the determined temporary work area on a map is displayed on the input/output device210. When the determined temporary work area is correct, the user inputs, to the input/output device210, an operation that stores the determined temporary work area. When the determined temporary work area is incorrect, the user inputs, to the input/output device210, a modification operation for the work area. For example, the user modifies the temporary work area to exclude an entrance from a farm road to the field500from the work area, as illustrated inFIG.11. Specifically, the user inputs operations to add vertices630, for example, a fifth vertex630-5, a sixth vertex630-6, and a seventh vertex630-7. The user also inputs an operation to delete a vertex630, for example, the fourth vertex630-4. The area determination unit250modifies the temporary work area on the basis of the input operations. The area determination unit250determines, as a work area640, a polygon that has the first vertex630-1, the second vertex630-2, the third vertex630-3, the fifth vertex630-5, the sixth vertex630-6, and the seventh vertex630-7as vertices.

In step S160illustrated inFIG.9, the area storage unit260stores area information representing the determined work area640in the work area data410. For example, the area storage unit260acquires information representing the position and shape of the work area640from the area determination unit250and stores the acquired information in the work area data410. The area storage unit260also stores a current date in the work area data410in association with the information representing the work area640.

In step S170, the route determination unit280determines a work route650for the first work device100to work on the basis of the determined work area640. For example, the route determination unit280determines the work route650, as illustrated inFIG.12, along which work is performed while reciprocating within the work area640. The work route650represents, for example, a route that moves from the first approximate straight line620-1to the third approximate straight line620-3while reciprocating between the fourth approximate straight line620-4and the second approximate straight line620-2, which are opposed to each other. The route determination unit280outputs route information representing the determined work route650to the first work device100. In addition, the route determination unit280updates, in the work area data410, the final use date of the area information corresponding to the work area640to a date when the work route650is determined.

In step S180illustrated inFIG.9, the first drive control unit150of the first work device100controls the first work device100so that the first work device100moves and works along the work route650represented in the acquired route information.

Thus, the work area management system1000determines the work area640on the basis of a circumferential route of the first work device100and controls the first work device100so that the first work device100performs work in the determined work area640.

The route determination unit280of the control device200determines a work route along which the second work device300performs work in the field500using area information on the work area640registered by using the first work device100. For example, when the second work device300performs work in the field500, the user inputs an operation to the input/output device210of the control device200to start work by the second work device300. The computing device220of the control device200reads and executes the work area management program420when an operation by the user is input. When the work area management program420is read and executed, the computing device220starts processing illustrated inFIG.13, which is part of a work area management method.

In step S210, the use area selection unit270accepts candidate area information used to determine a work route of the second work device300. For example, the use area selection unit270displays a list of area information stored in the work area data410on the input/output device210. From the list of displayed area information, the operator selects area information to be used for determining the work route of the second work device300as candidate area information.

In step S220, the use area selection unit270determines whether the candidate area information is suitable for determining the work route of the second work device300. When the candidate area information is suitable for determining the work route of the second work device300, the use area selection unit270performs processing of step S240. When the candidate area information is unsuitable for determining the work route of the second work device300, the use area selection unit270performs processing of step S230.

For example, when the candidate area information satisfies a predetermined condition, the use area selection unit270determines that the candidate area information is suitable for determining the work route of the second work device300. For example, the predetermined condition includes that a predetermined period of time or longer has not elapsed since the candidate area information was registered. For example, the use area selection unit270acquires, from the work area data410, information representing a registration date illustrated inFIG.7. When a predetermined period of time or longer, for example, five years or longer, has not elapsed since the registration date, the use area selection unit270determines that the candidate area information is suitable for determining the work route of the second work device300.

In the examples illustrated inFIG.7, the area information whose area positions are “A” and “B” is determined to be unsuitable for determining the work route of the second work device300because a predetermined period of time or longer has elapsed since the area information was registered. The area information whose area position is “C” is determined to be suitable for determining the work route of the second work device300, because a predetermined period of time or longer has not elapsed since the area information was registered. In some cases, the work area640may change. For example, the work area640changes in accordance with changes in the field500due to the joining or dividing of the field500. The work area640may change due to a change in position of a facility in the field500, such as an entrance for the second work device300to enter the field500, a water intake, or the like. Including the elapsed period of time since the candidate area information was registered in the predetermined condition reduces the use of work area640that have changed since being registered.

Even if a predetermined period of time or longer has elapsed since registration, when an elapsed period of time since last use is short, it is highly possible that the work area640has not changed. Therefore, the predetermined condition may include that a predetermined period of time or longer has not elapsed since the candidate area information was last used. The use area selection unit270acquires, from the work area data410, the information representing the final use date illustrated inFIG.7. When a predetermined period of time or longer, for example, two years or longer, has not elapsed since the final use date, the use area selection unit270determines that the candidate area information is suitable for determining the work route of the second work device300.

In the example illustrated inFIG.7, the area information whose area position is “A” is determined to be unsuitable for determining the work route of the second work device300because a predetermined period of time or longer has elapsed since the area information was used. The area information whose area positions are “B” and “C” is determined to be suitable for determining the work route of the second work device300because a predetermined period of time or longer has not elapsed since the area information was used.

The use area selection unit270may also determine whether the candidate area information is suitable for determining the work route of the second work device300on the basis of accuracy of the work area640represented in the candidate area information. For example, the longer the distance from the vertex630to the outer edge route610illustrated inFIG.10, the lower the accuracy of the vertex630of the work area640may be. Therefore, the use area selection unit270may determine whether the candidate area information is suitable for determining the work route of the second work device300on the basis of the distance from the vertex630to the outer edge route610illustrated inFIG.10. For example, the use area selection unit270determines that the candidate area information is suitable for determining the work route of the second work device300when the distance from the vertex630to the outer edge route610is smaller than a threshold value. In this case, the predetermined condition for determining appropriateness of determining the work route includes that the distance from the vertex630to the outer edge route610is smaller than a threshold value.

For example, as illustrated inFIGS.2and3, the accuracy of the work area640varies according to the model of work device used to register the work area640. For example, in many cases, the accuracy of the work area640registered using a rice transplanter is higher than that of the work area640registered using a tractor. In addition, in many cases, the accuracy of the work area640registered using a combine harvester is higher than that of the work area640registered using a rice transplanter. Therefore, the use area selection unit270may acquire the model of the work device used for registration from the work area data410and determine whether it is suitable for determining the work route of the second work device300.

For example, the use area selection unit270stores a first unsuitable model group that represents a list of models that are unsuitable for determining the work route. When the model of the work device used for registration is included in the first unsuitable model group, the use area selection unit270determines that the candidate area information is unsuitable for determining the work route of the second work device300. The first unsuitable model group may include, for example, a tractor. In this case, the predetermined condition for determining the appropriateness of determining the work route includes that the model of the work device used for registration is not included in the first unsuitable model group.

In addition, the use area selection unit270may also determine whether the candidate area information is suitable for determining the work route of the second work device300on the basis of the model of the work device whose work route is to be determined, for example, the model of the second work device300and the model of the work device used for registration. For example, the use area selection unit270stores, for the work device whose work route is to be determined, a second unsuitable model group which represents a list of models that are unsuitable in determining the work route. The use area selection unit270acquires information representing the model of the second work device300whose work route is to be determined. For example, information representing the model of the second work device300may be input into the input/output device210of the control device200by the operator or may be acquired from the second work device300. The use area selection unit270acquires a second unsuitable model group corresponding to the model of the second work device300. When the model of the work device used for registration is included in the second unsuitable model group, the use area selection unit270determines that the candidate area information is unsuitable for determining the work route of the second work device300. In this case, the predetermined condition for determining the appropriateness of determining the work route includes that the model of the work device used for registration is not included in the second unsuitable model group corresponding to the model of the second work device300whose work route is to be determined.

For example, when determining a work route for a combine harvester, the second unsuitable model group may include, for example, a tractor and a rice transplanter. When determining a work route for a rice transplanter, the second unsuitable model group may include, for example, a tractor. When determining a work route for a tractor, the second unsuitable model group need not include any models.

The use area selection unit270may determine that the candidate area information is suitable for determining the work route of the second work device300when all of the plurality of predetermined conditions are satisfied, or may determine that the candidate area information is suitable for determining the work route of the second work device300when some of the predetermined conditions are satisfied.

When it is determined that the candidate area information is unsuitable for determining the work route, in step S230illustrated inFIG.13, the use area selection unit270outputs warning information to the input/output device210to inform the operator that the selected candidate area information is unsuitable for determining the work route. The warning information may include a reason for the unsuitable determination, for example, information representing conditions that the candidate area information does not satisfy.

In step S240, the use area selection unit270outputs the selected candidate area information to the input/output device210. For example, the use area selection unit270displays, on the input/output device210, an image that represents the work area640represented by the selected candidate area information on a map. The operator checks the output candidate area information and decides whether to use the candidate area information to determine the work route of the second work device300.

In step S250, the use area selection unit270accepts the operator's decision to use the candidate area information. If the operator decides to use the candidate area information, he/she inputs, to the input/output device210, an operation indicating that the candidate area information is to be used to determine the work route. If the operator decides not to use the candidate area information, he/she inputs, to the input/output device210, an operation representing that the candidate area information is not to be used. When an operation representing that candidate area information is to be used is input, the processing moves to step S260. When an operation representing that the candidate area information is not to be used is input, the processing returns to step S210to repeat the above-mentioned processing.

In step S260, the route determination unit280determines a work route for the second work device300to perform work on the basis of the candidate area information. For example, as illustrated inFIG.14, the route determination unit280determines a work route750along which the second work device300moves to perform work in the work area640registered using the first work device100.

For example, the work route750includes a first work route750-1, a third work route750-3, a fifth work route750-5, and a seventh work route750-7that move in a straight line along the contour510of the field500. The work route750also includes a second work route750-2, a fourth work route750-4, and a sixth work route750-6that repeatedly move forward and backward to shift inward in the field500. Furthermore, the work route750includes an eighth work route750-8that moves toward a center of the field500while circulating along the contour510of the field500. The route information representing the determined work route750is output to the second work device300. In addition, the route determination unit280updates the final use date of the area information corresponding to work area640in the work area data410to a date when the work route750was determined.

In step S270illustrated inFIG.13, the second drive control unit350of the second work device300controls the second work device300so that the second work device300moves and works along the work route750represented in the acquired route information. For example, the second drive control unit350controls the second work device300to make the second work device300move along the route from the first work route750-1to the eighth work route750-8.

Thus, the work area management system1000controls the second work device300so that the second work device300performs work in the work area640determined on the basis of the circumferential route of the first work device100.

(Modified Examples) The configuration described in the embodiment is an example, and can be modified to an extent that does not interfere with the functions. For example, in step S120illustrated inFIG.9, the area determination unit250of the control device200may determine the circumferential direction on the basis of changes in the traveling direction of the first work device100. For example, as illustrated inFIG.2, when the first work device100circulates the work area in a counterclockwise direction, the traveling direction of the first work device100frequently changes to the left. Therefore, the area determination unit250determines the circumferential direction of the first work device100by integrating the changes in the traveling direction of the first work device100at each time. Here, the traveling direction of the first work device100is determined on the basis of, for example, two positional information that are measured continuously over time.

In step S220illustrated inFIG.13, the use area selection unit270of the control device200may use any values representing a distance from the vertex630to the route of the first work device100as the accuracy of the work area640represented in the candidate area information, and is not limited to the distance from the vertex630to the outer edge route610. For example, the use area selection unit270may represent the accuracy of the work area640by a distance from the vertex630to the registration route600. The accuracy of the work area640may be represented by a distance from a measured positioning position that is closest to the vertex630among the measured positioning positions of the first work device100to the vertex630. The accuracy of the work area640may be represented by a distance from an outer edge position that is closest to the vertex630among the outer edge positions on the outer edge route610relative to the positioning positions of the first work device100to the vertex630. Here, the outer edge position represents a position of an outside end of the first work device100when the positioning position of the first work device100is measured. The outer edge position represents, for example, a position of a right end of the first work device100when the circumferential direction is counterclockwise, and a position of a left end of the first work device100when the circumferential direction is clockwise.

The accuracy of the work area640may be represented by a statistically determined value, such as a maximum, minimum, average, or median value, in a plurality of values representing the distances from the plurality of vertices630to the route of the first work device100. For example, the use area selection unit270determines that the larger the value representing the distance, the lower the accuracy of the work area640is.

In step S210illustrated inFIG.13, the use area selection unit270of the control device200may limit the list of area information to be displayed on the input/output device210on the basis of the position of the second work device300. For example, the second drive control unit350of the second work device300outputs, to the control device200, position information representing the position of the second work device300measured by the sensor315. The use area selection unit270of the control device200may extract area information corresponding to the work area640where the distance from the position of the second work device300is smaller than a threshold value and output a list of the extracted area information.

In step S210, the use area selection unit270may output a list of area information representing degrees of appropriateness for determining the work route750. For example, the use area selection unit270outputs a list of area information so that the area information is displayed in order of decreasing degree of appropriateness. The use area selection unit270may also calculate the degree of appropriateness for each area information and output a list with the calculated degree of appropriateness added to the area information.

For example, the use area selection unit270determines that an area information that has a shorter elapsed time since the registration date when the work area640was registered has a higher degree of appropriateness for determining the work route750. The use area selection unit270may also determine that an area information that has a shorter elapsed time since the final use date last used to determine the work route750has a higher degree of appropriateness for determining the work route750. The use area selection unit270may also determine that the smaller the value representing the distance from the vertex630to the route of the first work device100in the work area640represented in the area information, the higher the degree of appropriateness for determining the work route750. The use area selection unit270may use a plurality of indicators, for example, two or more of the following: the elapsed time since the registration date, the elapsed time since the last use date, or the value representing the distance from the vertex630to the route of the first work device100, to determine the degree of appropriateness. The use area selection unit270may also use the model of the work device used to register the work area640to determine the degree of appropriateness.

In step S210, which is moved from step S250, the use area selection unit270may limit the list of area information to be displayed on the input/output device210on the basis of the previously selected candidate area information. For example, the use area selection unit270may extract area information representing the work area640that matches the work area640represented by the previously selected candidate area information and output a list of the extracted area information. For example, the use area selection unit270extracts area information representing, among the work areas640represented in the previously selected candidate area information, the work areas640that contain an area whose percentage is greater than or equal to a threshold value.

The use area selection unit270may also extract area information in which the area of overlapping area between the work area640represented by the previously selected candidate area information and the work area640represented by the area information is greater than a predetermined ratio to the areas of the respective work areas640. For example, the use area selection unit270selects one area information and calculates the area of overlapping area between the first work area represented by the previously selected candidate area information and the second work area represented by the selected area information. When the area of the overlapping area is greater than a predetermined ratio to the area of the first work area and greater than a predetermined ratio to the area of the second work area, the use area selection unit270extracts the selected area information.

The use area selection unit270may also extract area information representing the work area640that is similar to the shape of the work area640represented in the previously selected candidate area information. For example, on the basis of the quantity of the vertices630and the distance of the vertices630corresponding to each other, the use area selection unit270determines the similarity between the shape of the work area640represented in the previously selected candidate area information and the shape of the work area640represented in the area information. The use area selection unit270extracts area information whose determined similarity is greater than a threshold value.

In step S210, the use area selection unit270may accept registration of the work area by the second work device300. For example, the operator inputs, to the input/output device210, an operation representing that a work area is to be registered by the second work device300. When the operation by the operator is input, the use area selection unit270ends the processing illustrated inFIG.13and starts the processing illustrated inFIG.9.

The embodiment and the modified examples that have been described above are merely examples, and the configurations described in the embodiment and the modified examples may be arbitrarily changed and/or arbitrarily combined to an extent that does not interfere with the functions to be aimed. Furthermore, part of the functions that have been described in the embodiment and the modified examples may be omitted on condition that the necessary functions can be realized. For example, in step S150illustrated inFIG.9, the area determination unit250may determine the work area640without accepting a modification operation of the work area640by the user.

For example, the first work device100or the second work device300may perform part of the processing of the control device200. The work area management system1000may also include an area storage device30that is connected to the control device200via network20, as illustrated inFIG.15. In this case, the area storage device30performs part of the processing of the control device200. For example, the area storage device30may realize the area storage unit260and the use area selection unit270illustrated inFIG.5. In this case, the information to be displayed on the input/output device210of the control device200is output from the area storage device30to the control device200and displayed on the input/output device210of the control device200. In addition, the work area management program420may include the first drive control program400and the second drive control program430.

The work area management system1000may also include a plurality of the control devices200when including the area storage device30. In this case, the control device200may determine a work route using the work area640registered by other control devices200, because the area storage device30includes the work area data410that stores the work area640.

The control device200may control a plurality of work devices, for example, all of the work devices that work in the field500. The control device200may also control a work device that is not included in the work area management system1000. In this case, the work area management system1000may not need to include work devices, for example, the first work device100and the second work device300.

As illustrated inFIG.16, when the operator moves the first work device100along the contour of the work area640to register the work area640, a real time kinematic (RTK) positioning method is used to accurately measure the position of the first work device100, and a fixed reference station520may be installed temporarily. In the RTK positioning method, the fixed reference station520is installed at a position in the vicinity of the field with a pre-specified latitude and longitude. The fixed reference station520transmits a difference between the installed position (latitude and longitude) and the position (latitude and longitude) measured by the GNSS receiver at the fixed reference station520as correction information. The first work device100measures positions with high accuracy by correcting the positions measured by the positioning device using the correction information acquired from the fixed reference station520. In this case, the control device200may store, in the work area data410, reference station information that represents latitude and longitude indicating a position of the fixed reference station520, for example, a specific position where the fixed reference station520is installed. For example, the area storage unit260of the control device200includes the reference station information in the area information and stores the reference station information in the work area data410. The reference station information may be any information for identifying each fixed reference station520, as long as the reference station information may represent the position of each fixed reference station520. The specific position where the fixed reference station520is installed may represent an average value of the positions measured by the fixed reference station520for a plurality of times in a state where the fixed reference station520has been installed.

When the positions of the fixed reference station520are different, the work information registered in the work of the first work device100may not be used in the work of the second work device300due to errors in the positions measured in the second work device300. Therefore, in step S210illustrated inFIG.13, when area information including reference station information is selected, the use area selection unit270of the control device200may determine whether the selected area information is suitable for determining the work route on the basis of the position where the fixed reference station520is installed. For example, the predetermined condition in step S220may include that to position of the fixed reference station520installed for the second work device300to perform work is equal to the position of the fixed reference station520represented in the candidate area information.

In this case, the use area selection unit270acquires installation position information representing the installed position from the installed fixed reference station520. The use area selection unit270determines that the selected area information is suitable for determining the work route when the position represented by the acquired installation position information is equal to the position of the reference station information included in the area information. For example, the use area selection unit270determines that two positions are equal when a distance from the position represented by the acquired installation position information to the position of the reference station information included in the area information is smaller than a threshold value. When the use area selection unit270determines that the two positions are different, in step S230, the use area selection unit270may output warning information to encourage the user to install the fixed reference station520in a correct position. For example, the use area selection unit270may output information representing the correct position of the fixed reference station520.

In step S150illustrated inFIG.9, the user may also register entrance information representing a position of the entrance of the field500. For example, the area determination unit250displays an image representing the determined work area640on a map. The user inputs an operation to the input/output device210to specify the position of an entrance660in the displayed image, as illustrated inFIG.17. The area determination unit250accepts entrance information representing the position of the specified entrance660. In step S160, the accepted entrance information is included in the area information and stored in the work area data410by the area storage unit260.

When area information including the entrance information is selected in step S210illustrated inFIG.13, the route determination unit280of the control device200may use the position represented by the entrance information as a starting or ending point of the work route750. This facilitates the determination of the work route750.

The work area data410may also store change information representing that the shape of the field500corresponding to the registered work area640has been changed. For example, the user inputs an operation to the input/output device210of the control device200to register that the shape of the field500corresponding to the work area640has been changed. When the operation by the user is input, the area storage unit260of the control device200accepts the change information representing the area information corresponding to the field500whose shape has been changed. For example, the area storage unit260displays, on the input/output device210, a list of area information stored in the work area data410. The user selects, from the list of area information displayed, the area information representing the work area640corresponding to the field500whose shape has been changed. The area storage unit260adds the change information representing that the shape of the corresponding field500has been changed to the selected area information and stores the information in the work area data410. In this case, in step S210illustrated inFIG.13, when a list of area information is displayed, the use area selection unit270excludes the area information representing the work area640corresponding to the field500whose shape has been changed. The area storage unit260may also accept change information from other systems representing that the shape of the field500has been changed.

In step S170illustrated inFIG.9and step S260illustrated inFIG.13, the route determination unit280may store one or more pieces of route information representing one or more determined work routes650and750. For example, the route determination unit280may store the route information in work route data450included in the storage device140, as illustrated inFIG.18. The stored route information representing the work route650may be used later when the first work device100performs work in the field500. For example, the operator may move the first work device100along the work route650of the route information stored in the route determination unit280and used for past work to perform new work in the field500.

In this case, the operator selects route information to be used for the work of the first work device100from the list of route information displayed on the input/output device210of the control device200. The route determination unit280outputs the selected route information to the first work device100. The first drive control unit150of the first work device100moves the first work device100along the work route650represented by the selected route information. Similarly, the stored route information representing the work route750may be used later when the second work device300performs work in the field500.

The route information may be stored in association with the work area640used when the work routes650and750represented in the route information were determined. In this case, the route information is grouped according to the work area640used when the work routes650and750represented in the route information were determined. For example, when the shape of the field500corresponding to the work area640has been changed, the route determination unit280of the control device200may warn the operator when any route information represented in association with the work area640corresponding to the changed field500is used.

In this case, the area storage unit260accepts change information representing that the shape of the field500corresponding to the work area640has been changed. On the basis of the accepted change information, the area storage unit260adds the change information to the corresponding area information among the area information stored in the work area data410. When the operator uses any route information represented in association with the work area640corresponding to the field500whose shape has been changed, the route determination unit280outputs, to the input/output device210, warning information representing that the route information being used is not appropriate thereby warning the operator. For example, the route determination unit280displays a list of route information stored in the work route data450on the input/output device210. The operator selects route information to be used for the work by the second work device300from the displayed list of route information. On the basis of the work area640represented by the selected route information, the route determination unit280acquires area information representing the work area640from the work area data410. When the acquired area information includes change information representing that the shape of the corresponding field500has been changed, the route determination unit280outputs warning information to the input/output device210. The warning information represents, for example, that the shape of the field500used in determining the work routes650and750represented in the selected route information has been changed.

In step S180illustrated inFIG.9, the first work device100may output operation information acquired from the sensor115to the control device200when performing work in the field. In step S270illustrated inFIG.13, the second work device300may output operation information acquired from the sensor315to the control device200when performing work in the field. In these cases, the area determination unit250of the control device200may store the acquired operation information in the storage device140in association with the route information representing the work route650of the first work device100or the work route750of the second work device300. For example, when the route information is associated with the work area640, the operation information may be stored in association with the work area640with which the corresponding route information is associated. The area determination unit250may store the operation information in the storage device140in association with area information representing the work area640used to determine the work route650of the first work device100or the work route750of the second work device300. As a result, the operation information is grouped according to area information. This enables operation information related to work performed in the same work area640to be grouped together and stored in the storage device140. By grouping the operation information related to work performed in the same work area640, information related to work performed in the same field500is grouped together. This enables the operator to efficiently perform farm management.

The work area management method, work area management system, and work area management program described in each embodiment can be described as follows.

A work area management method according to a first aspect includes storing first area information that represents a first work area for determining a first work route along which a first work device moves to perform a first work in a field, and that is determined on the basis of a positioning position of the first work device, and outputting the first area information as information that represents an area for determining a second work route along which a second work device different from the first work device moves to perform a second work in the field.

A work area management method according to a second aspect is the work area management method according to the first aspect, in which the outputting the first area information includes outputting warning information representing that the first area information is unsuitable for determining the second work route when the first area information does not satisfy a predetermined condition.

A work area management method according to a third aspect is the work area management method according to the second aspect, in which the first work area is formed by a polygon, and the outputting the warning information includes outputting the warning information on the basis of a distance from a vertex of the first work area to a registration route represented by the positioning position of the first work area.

A work area management method according to a fourth aspect is the work area management method according to the second or third aspect, in which the predetermined condition includes that a predetermined time or longer has not elapsed since the first area information was registered.

A work area management method according to a fifth aspect is the work area management method according to any one of the second to fourth aspects, in which the predetermined condition includes that a predetermined time or longer has not elapsed since the first area information was used to determine a work route.

A work area management method according to a sixth aspect is the work area management method according to any one of the second to fifth aspects, in which the predetermined condition includes that a model of the first work device is not included in a first unsuitable model group that represents models of work devices that are unsuitable in determining a work route of a work device.

A work area management method according to a seventh aspect is the work area management method according to any one of the second to sixth aspects, in which the predetermined condition includes that a model of the first work device is not included in a second unsuitable model group that represents models of work devices that are unsuitable in determining the second work route of the second work device.

A work area management method according to an eighth aspect is the work area management method according to any one of the first to seventh aspects, in which the first area information includes reference station information that represents a position of a fixed reference station installed when the first work area is determined by the first work device to improve accuracy in measuring a position of the first work device, and the predetermined condition includes that a position of the fixed reference station installed for the second work device to perform the second work is equal to the position of the fixed reference station represented in the reference station information.

A work area management method according to a ninth aspect is the work area management method according to any one of the first to eighth aspects, in which the storing the first area information includes storing a plurality of pieces of area information including the first area information, and the outputting the first area information includes outputting a list of the plurality of pieces of area information each representing a degree of appropriateness in determining the second work route of the second work device, and accepting area information selected by an operator from the outputted list of the plurality of pieces of area information as the first area information.

A work area management method according to a tenth aspect is the work area management method according to any one of the first to ninth aspects, in which the second work is different from the first work.

A work area management method according to an 11th aspect is the work area management method according to any one of the first to tenth aspects, which includes determining the first work route along which the first work device moves to perform the first work in the first work area, and determining the second work route along which the second work device moves to perform the second work in the first work area.

A work area management method according to a 12th aspect is the work area management method according to any one of the first to 11th aspects, in which the first area information includes entrance information representing a position of an entrance of the field.

A work area management method according to a 13th aspect is the work area management method according to any one of the first to 12th aspects, which includes storing one or more pieces of route information that represent one or more work routes determined on the basis of the first work area in association with the first work area.

A work area management method according to a 14th aspect is the work area management method according to the 13th aspect, which includes accepting change information representing that a shape of the field corresponding to the first work area has been changed, and outputting, according to the change information, warning information representing that the shape of the field used in determining the work route represented in the first route information has been changed when any first route information included in the one or more pieces of route information represented in association with the first work area is used.

A work area management method according to a 15th aspect is the work area management method according to any one of the first to 14th aspects, which includes storing first operation information representing a state when the first work device moved along the first work route in association with the first area information, and storing second operation information representing a state when the second work device moved along the second work route in association with the first area information.

A work area management system according to a 16th aspect has an area storage unit that stores first area information representing a first work area for determining a first work route along which a first work device moves to perform a first work in a field and that is determined on the basis of a positioning position of the first work device, and a use area selection unit that outputs the first area information as information representing an area in the field that The area selection unit outputs the first area information as information representing an area for determining a second work route along which a second work device different from the first work device moves to perform the second work in the field.

A work area management program according to a 17th aspect causes a computing device to execute storing first area information that represents a first work area for determining a first work route along which a first work device moves to perform a first work in a field, and that is determined on the basis of a positioning position of the first work device, and outputting the first area information as information that represents an area for determining a second work route along which a second work device different from the first work device moves to perform a second work in the field.

REFERENCE SIGNS LIST

1,2,3: Storage medium20: Network30: Area storage device100: First work device110: Key switch115: Sensor120: Computing device130: Communication device140: Storage device150: First drive control unit200: Control device210: Input/output device220: Computing device230: Communication device240: Storage device250: Area determination unit260: Area storage unit270: Use area selection unit280: Route determination unit300: Second work device310: Key switch315: Sensor320: Computing device330: communication device340: Storage device350: Second drive control unit400: First drive control program410: Work area data420: Work area management program430: Second drive control program450: Work route data500: Field510: Contour520: Fixed reference station600: Registration route610: Outer edge route620: Approximate straight line630: Vertex640: Work area (first work area)650: Work route (first work route)660: Entrance700: Registration route750: Work route (second work route)1000: Work area management system