Patent Description:
There is known a work vehicle automatically traveling on a target route while spraying a chemical liquid on crops planted in a work area such as a farm field or an agricultural farm (see, for example, Patent Document <NUM>). The work vehicle sprays the chemical liquid in a left-right direction within a work route while automatically traveling sequentially on a plurality of work routes where the crops are planted. Document <CIT> relates to the field of vehicle control, and in particular to a method, device, and equipment for controlling the driving direction of a vehicle.

The work vehicle includes a function of performing a correction operation for correcting a position of the work vehicle or an orientation thereof if a position deviation (deviation in position) or an orientation deviation (deviation in orientation) with respect to the target route exceeds a threshold value (allowable value) to avoid collision against crops during automatic travel. Therefore, for example, in a case where a condition of a farm field is not good and in a case where the farm field is sloped, as a result of the position deviation or the orientation deviation frequently exceeding the threshold value, the correction operation is repeatedly executed. This causes a problem that the work efficiency of a work with the work vehicle is reduced.

An object of the present invention relates to an automatic traveling method, an automatic traveling system, and an automatic traveling program, by which it is possible to improve work efficiency of a work performed by a work vehicle traveling automatically.

The present invention is defined in claims <NUM>, <NUM> and <NUM> and relates to an automatic traveling method according includes causing a work vehicle to automatically travel according to a target route in a work area where crops are planted, changeably setting, with respect to the target route, a threshold value of a deviation including at least one of a position deviation and an orientation deviation of the work vehicle, and causing the work vehicle to execute a correction operation for correcting the deviation if the deviation exceeds the threshold value, to avoid collision against the crops during automatic travelling.

An automatic traveling system according to the present invention includes a travel processing unit, a setting processing unit, and a correction processing unit. The travel processing unit causes the work vehicle to automatically travel according to a target route in a work area where crops are planted. The setting processing unit changeably sets, with respect to the target route, a threshold value of a deviation including at least one of the position deviation and the orientation deviation of the work vehicle. The correction processing unit executes a correction operation for correcting the deviation of the work vehicle if the deviation exceeds the threshold value, to avoid collision against the crops during automatic travelling.

An automatic traveling program according to the present invention is a program for causing one or more processors to execute causing a work vehicle to automatically travel according to a target route in a work area where crops are planted, changeably setting, with respect to the target route, a threshold value of a deviation including at least one of a position deviation and an orientation deviation of the work vehicle, and causing the work vehicle to execute a correction operation for correcting the deviation if the deviation exceeds the threshold value, to avoid collision against the crops during automatic travelling.

According to the present invention, it is possible to provide an automatic traveling method, an automatic traveling system, and an automatic traveling program, by which a work vehicle traveling automatically can improve work efficiency of a work.

The following embodiment is an example in which the present invention is embodied, and does not limit the technical scope of the present invention defined in the claims.

As illustrated in <FIG> and <FIG>, an automatic traveling system <NUM> according to the embodiment of the present invention includes a work vehicle <NUM>, an operation terminal <NUM>, a base station <NUM>, and a satellite <NUM>. The work vehicle <NUM> and the operation terminal <NUM> can communicate with each other via a communication network N1. For example, the work vehicle <NUM> and the operation terminal <NUM> can communicate via a mobile phone line network, a packet line network, or a wireless LAN.

In the present embodiment, a case where the work vehicle <NUM> is a vehicle that performs a spraying work of spraying a chemical liquid, water, or the like on crops V (see <FIG>) planted in a farm field F will be described as an example. The farm field F is an example of a work area in the present invention, and the farm field F is, for example, an orchard such as a vineyard or an apple orchard. The crops V are, for example, grape trees. The spraying work is, for example, a work for spraying a spraying material such as a chemical liquid or water on the crops V. As another embodiment, the work vehicle <NUM> may be a vehicle for performing a weeding work, a vehicle for performing a leaf cutting work, or a vehicle for performing a harvesting work.

The crops V are arranged in a plurality of rows at predetermined intervals in the farm field F. Specifically, as illustrated in <FIG>, a plurality of the crops V are planted linearly in a predetermined direction (a D1 direction), and form a crop row Vr including the plurality of crops V arranged linearly. <FIG> illustrates three of the crop rows Vr. The crop rows Vr are arranged at a predetermined interval W1 in the row direction (a D2 direction). A region (space) having an interval W2 between adjacent ones of the crop rows Vr is a work passage where the work vehicle <NUM> performs a spraying work on the crops V while traveling in the D1 direction. The crop row Vr is an example of a row of targets to be sprayed according to the present invention.

The work vehicle <NUM> is capable of traveling automatically (autonomously traveling) along a target route R set in advance. For example, as illustrated in <FIG>, the work vehicle <NUM> automatically travels from a work start position S to a work end position G along the target route R including a work route R1 (work routes R1a to R1f) and a movement route R2. The work route R1 is a linear route on which the work vehicle <NUM> performs the spraying work on the crops V, and the movement route R2 is a route on which the work vehicle <NUM> moves between the crop rows Vr without performing the spraying work. The movement route R2 includes, for example, a turning route and a straight route. In the example illustrated in <FIG>, the crops V forming crop rows Vr1 to Vr11 are arranged in the farm field F. In <FIG>, positions (crop positions) where the crops V are planted are represented by "Vp". The work vehicle <NUM> traveling in the farm field F of <FIG> includes a vehicle body <NUM> having an inverted U-shape (see <FIG>), and while traveling in a state of spanning over one of the crop rows Vr, the work vehicle <NUM> sprays a chemical liquid on the crops V in the one crop row Vr and on the crop row Vr adjacent to the one crop row Vr. For example, as illustrated in <FIG>, if the work vehicle <NUM> travels in a state of spanning over the crop row Vr5, a left-side vehicle body (a left-side part <NUM>) of the work vehicle <NUM> travels on a work passage between the crop rows Vr4 and Vr5, a right-side vehicle body (a right-side part 100R) of the work vehicle <NUM> travels on a work passage between the crop rows Vr5 and Vr6, and the work vehicle <NUM> sprays a chemical liquid on the crops V of the crop rows Vr4, Vr5, and Vr6.

The work vehicle <NUM> automatically travels in a predetermined row order. For example, the work vehicle <NUM> firstly travels across the crop row Vr1, next, travels across the crop row Vr3, and next, travels across the crop row Vr5. Thus, the work vehicle <NUM> automatically travels according to a preset order of the crop rows Vr. The work vehicle <NUM> may travel on each row in the order of arrangement of the crop rows Vr, or may travel in each of plurality of rows.

The satellite <NUM> is a positioning satellite configuring a satellite positioning system such as a global navigation satellite system (GNSS), and transmits a GNSS signal (satellite signal). The base station <NUM> is a reference point (reference station) configuring the satellite positioning system. The base station <NUM> transmits, to the work vehicle <NUM>, correction information for calculating a current position of the work vehicle <NUM>.

A positioning device <NUM> mounted in the work vehicle <NUM> executes a positioning process for calculating a current position (a latitude, a longitude, and an altitude), a current orientation, and the like of the work vehicle <NUM> by utilizing the GNSS signal transmitted from the satellite <NUM>. Specifically, the positioning device <NUM> positions the work vehicle <NUM> by utilizing a real time kinetic (RTK) method or the like for positioning the work vehicle <NUM>, based on positioning information (such as a GNSS signal) received by two receivers (an antenna <NUM> and the base station <NUM>) and correction information generated by the base station <NUM>. The positioning method is a well-known technique, and thus, detailed description thereof will be omitted.

Each constituent components configuring the automatic traveling system <NUM> will be described in detail below.

<FIG> is an external view obtained when the work vehicle <NUM> is viewed from a left front side. <FIG> is an external view of a left side face obtained when the work vehicle <NUM> is viewed from a left side, <FIG> is an external view of a right side face obtained when the work vehicle <NUM> is viewed from a right side, and <FIG> is an external view of a rear face obtained when the work vehicle <NUM> is viewed from a rear face side.

As illustrated in <FIG>, the work vehicle <NUM> includes a vehicle control device <NUM>, a storage unit <NUM>, a travel device <NUM>, a spray device <NUM>, a communication unit <NUM>, a positioning device <NUM>, and an obstacle detection device <NUM>, for example. The vehicle control device <NUM> is electrically connected to the storage unit <NUM>, the travel device <NUM>, the spray device <NUM>, the positioning device <NUM>, and the obstacle detection device <NUM>, for example. The vehicle control device <NUM> and the positioning device <NUM> may be capable of performing wireless communication.

The communication unit <NUM> is a communication interface for connecting the work vehicle <NUM> to the communication network N1 in a wired or wireless manner to execute data communication according to a predetermined communication protocol between the work vehicle <NUM> and an external device such as the operation terminal <NUM> via the communication network N1.

The storage unit <NUM> is a non-volatile storage unit including a hard disk drive (HDD) or a solid state drive (SSD) that stores various types of information. The storage unit <NUM> stores a control program such as an automatic traveling program for causing the vehicle control device <NUM> to execute an automatic traveling process (see <FIG> and <FIG>) described later. For example, the automatic traveling program is recorded non-temporarily on a computer-readable recording medium such as a CD or a DVD, and is read by a predetermined reading device (not illustrated) to be stored in the storage unit <NUM>. It is noted that the automatic traveling program may be downloaded from a server (not illustrated) to the work vehicle <NUM> via the communication network N1 and stored in the storage unit <NUM>. The storage unit <NUM> stores route data including information on the target route R generated by the operation terminal <NUM> and deviation information F1 and F2 (described later) on deviations (the position deviation and the orientation deviation) of the work vehicle <NUM>. For example, the route data is transferred from the operation terminal <NUM> to the work vehicle <NUM> to be stored in the storage unit <NUM>.

The vehicle control device <NUM> includes a control device such as a CPU, a ROM, and a RAM. The CPU is a processor that executes various types of arithmetic processes. The ROM is a non-volatile storage unit in which a control program such as BIOS and OS for causing the CPU to execute various types of arithmetic processes is stored in advance. The RAM is a volatile or non-volatile storage unit that stores various types of information, and is used as a temporary storage memory (working area) for various types of processes executed by the CPU. The vehicle control device <NUM> controls the work vehicle <NUM> by causing the CPU to execute various types of control programs stored in advance in the ROM or the storage unit <NUM>.

The vehicle control device <NUM> controls the travel of the work vehicle <NUM>. Specifically, as illustrated in <FIG>, the vehicle control device <NUM> includes various types of processing units such as a travel processing unit <NUM>, a detection processing unit <NUM>, a correction processing unit <NUM>, and a setting processing unit <NUM>. The vehicle control device <NUM> functions as the various types of processing units by causing the CPU to execute various types of processes according to the control programs. Some or all of the processing units may be configured by an electronic circuit. The control programs may be programs for causing a plurality of processors to function as the processing units.

The travel processing unit <NUM> causes the work vehicle <NUM> to automatically travel along the target route R, based on positioning information including a position and an orientation of the work vehicle <NUM> positioned by the positioning device <NUM>. For example, when the positioning state is a state where RTK positioning is possible and an operator depresses a start button on an operation screen of the operation terminal <NUM>, the operation terminal <NUM> outputs a work start instruction to the work vehicle <NUM>. When acquiring the work start instruction from the operation terminal <NUM>, the travel processing unit <NUM> causes the work vehicle <NUM> to start automatic travel, based on the positioning information of the work vehicle <NUM> positioned by the positioning device <NUM>. Thus, the work vehicle <NUM> starts automatic travel along the target route R, and starts the spraying work by the spray device <NUM> in the work passage.

When acquiring a travel stop instruction from the operation terminal <NUM>, the travel processing unit <NUM> causes the work vehicle <NUM> to stop automatic travel. For example, if the operator depresses a stop button on the operation screen of the operation terminal <NUM>, the operation terminal <NUM> outputs the travel stop instruction to the work vehicle <NUM>. When acquiring the travel stop instruction from the operation terminal <NUM>, the travel processing unit <NUM> causes the work vehicle <NUM> to stop automatic travel. Thus, the work vehicle <NUM> stops the automatic travel and stops the spraying work by the spray device <NUM>. The travel processing unit <NUM> is an example of the travel processing unit according to the present invention.

Here, the work vehicle <NUM> includes an inverted U-shaped vehicle body <NUM> that travels across the crops V (fruit trees) planted side by side in a plurality of rows in the farm field F. As illustrated in <FIG>, the vehicle body <NUM> is formed in an inverted U-shape by the left-side part <NUM>, the right-side part 100R, and a connection unit 100C connecting the left-side part <NUM> and the right-side part 100R, and a space <NUM> that allows the passage of the crops V is secured inside the left-side part <NUM>, the right-side part 100R, and the connection unit 100C.

A crawler <NUM> is provided at the lower end of each of the left-side part <NUM> and the right-side part 100R of the vehicle body <NUM>. The left-side part <NUM> is provided with an engine (not illustrated), a battery (not illustrated), and the like. The right-side part 100R is provided with a storage tank 14A (see <FIG>) of the spray device <NUM> and the like. Thus, constitution components are arranged in a distributed manner in the left-side part <NUM> and the right-side part 100R of the vehicle body <NUM>, and thus, a balance between the left and right sides and a low center of gravity are achieved in the work vehicle <NUM>. Thus, the work vehicle <NUM> can stably travel on a slope or the like of the farm field F.

The travel device <NUM> is a drive unit that causes the work vehicle <NUM> to travel. The travel device <NUM> includes the engine, the crawler <NUM>, and the like.

The left and right crawlers <NUM> are driven by power from the engine in a state where independent transmission is possible by a hydrostatic continuously variable transmission. Thus, when the left and right crawlers <NUM> are driven at a constant speed in the forward direction, the vehicle body <NUM> is in a forward-moving state of moving straight in the forward direction, and when the left and right crawlers <NUM> are driven at a constant speed in the backward direction, the vehicle body <NUM> is in a backward-moving state of moving straight in the backward direction. When the left and right crawlers <NUM> are driven at an irregular speed in the forward direction, the vehicle body <NUM> is in a forward-moving and turning state where the vehicle body <NUM> moves forward while turning, and when the left and right crawlers <NUM> are driven at an irregular speed in the backward direction, the vehicle body <NUM> is in a backward-moving and turning state where the vehicle body <NUM> moves backward while turning. When one of the left and right crawlers <NUM> is stopped in drive while the other one of the crawlers <NUM> is driven, the vehicle body <NUM> is in a pivot turning (pivot turn) state, and when the left and right crawlers <NUM> are driven at a constant speed in the forward direction and in the backward direction, the vehicle body <NUM> is in a spin turning (neutral turn) state. When the left and right crawlers <NUM> are stopped in drive, the vehicle body <NUM> stops traveling. The left and right crawlers <NUM> may have an electrically driven configuration in which the left and right crawlers <NUM> are driven by an electric motor.

As illustrated in <FIG>, the spray device <NUM> includes the storage tank 14A that stores chemical liquids or the like, a spraying pump (not illustrated) that pumps chemical liquids or the like, an electric spraying motor (not illustrated) that drives the spraying pump, two spraying pipes 14B installed in parallel on each of the left and right in a vertical position at the rear of the vehicle body <NUM>, a total of <NUM> spraying nozzles 14C in which three nozzles are installed on each of the spraying pipes 14B, an electronically controlled valve unit (not illustrated) that changes a spraying amount and a spraying pattern of a chemical liquid, a plurality of spraying pipes (not illustrated) that connects these components, and the like.

Each of the spraying nozzles 14C is changeably attached to the corresponding spraying pipe 14B to be vertically repositionable. Thereby, each of the spraying nozzles 14C can change a distance from an adjacent spraying nozzle 14C and a height position with respect to the spraying pipe 14B according to the targets (crops V) to be sprayed. Further, each of the spraying nozzles 14C is attached so that the height position and the left-right position with respect to the vehicle body <NUM> can be changed according to the targets to be sprayed.

In the spray device <NUM>, the number of the spraying nozzles 14C provided in each of the spraying pipes 14B can be variously changed according to the type of crops V, the length of each of the spraying pipes 14B, and the like.

As illustrated in <FIG>, three spraying nozzles 14C provided on the leftmost spraying pipe 14B out of the plurality of spraying nozzles 14C spray the chemical liquid to the left toward a crop Va located on the leftward and outward of the vehicle body <NUM>. Three spraying nozzles 14C provided on the left inner spraying pipe 14B adjacent to the leftmost spraying pipe 14B out of the plurality of spraying nozzles 14C spray the chemical liquid to the right toward a crop Vb located in the left and right central space <NUM> of the vehicle body <NUM>. Three spraying nozzles 14C provided on the rightmost spraying pipe 14B out of the plurality of spraying nozzles 14C spray the chemical liquid to the right toward a crop Vc located on the rightward and outward of the vehicle body <NUM>. Three spraying nozzles 14C provided on the right inner spraying pipe 14B adjacent to the rightmost spraying pipe 14B out of the plurality of spraying nozzles 14C spray the chemical liquid to the left toward the crop Vb located in the space <NUM>.

With the above configuration, in the spray device <NUM>, the two spraying pipes 14B and the six spraying nozzles 14C provided on the left-side part <NUM> of the vehicle body <NUM> function as a left spraying unit <NUM>. Further, the two spraying pipes 14B and the six spraying nozzles 14C provided on the right-side part 100R of the vehicle body <NUM> function as a right spray portion 14R. The left and right spraying units <NUM> and 14R are provided with a horizontal interval allowing for passage of the crop Vb (the space <NUM>) between the left and right spraying units <NUM> and 14R in a state where the left and right spraying units <NUM> and 14R can spray the chemical liquid in the left-right direction on the rear of the vehicle body <NUM>.

In the spray device <NUM>, the spraying patterns of the spraying units <NUM> and 14R include a four-way spraying pattern in which each of the spraying units <NUM> and 14R sprays the chemical liquid in both the left and right directions, and a direction-restricted spraying pattern in which the spraying direction of the spraying units <NUM> and 14R is restricted. The direction-restricted spraying pattern includes a left-side three-way spraying pattern in which the spraying unit <NUM> sprays the chemical liquid in both the left and right directions and the spraying unit 14R sprays the chemical liquid only in the left direction, and a right-side three-way spraying pattern in which the spraying unit <NUM> sprays the chemical liquid only in the right direction and the spraying unit 14R sprays the chemical liquid in both the left and right directions, a two-way spraying pattern in which the spraying unit <NUM> sprays the chemical liquid only in the right direction and the spraying unit 14R sprays the chemical liquid only in the left direction, a left-side unidirectional spraying pattern in which the spraying unit <NUM> sprays the chemical liquid only in the left direction and the spraying unit 14R does not spray the chemical liquid, and a right-side unidirectional spraying pattern in which the spraying unit 14R sprays the chemical liquid only in the right direction and the spraying unit <NUM> does not spray the chemical liquid.

The vehicle body <NUM> is equipped with an automatic travel control unit that causes the vehicle body <NUM> to automatically travel according to the target route R of the farm field F, based on the positioning information and the like acquired from the positioning device <NUM>, an engine control unit that controls the engine, a hydro-static transmission (HST) control unit that controls the hydrostatic continuously variable transmission, and a work device control unit that controls a work device such as the spray device <NUM>. Each of the control units is constructed by an electronic control unit equipped with a microcontroller and the like, various types of information and control programs stored in a non-volatile memory (for example, an EEPROM such as a flash memory) of the microcontroller, and the like. The various types of information stored in the non-volatile memory may include the target route R generated in advance or the like. In the present embodiment, the control units are collectively referred to as the "vehicle control device <NUM>" (see <FIG>).

The positioning device <NUM> is a communication equipment including a positioning control unit <NUM>, a storage unit <NUM>, a communication unit <NUM>, the antenna <NUM>, and the like. The antenna <NUM> is provided at the front and rear parts of a roof (the connection unit 100C) of the vehicle body <NUM> (see <FIG>). The roof of the vehicle body <NUM> is also provided with an indication lamp <NUM> or the like for indicating a travel state of the work vehicle <NUM> (see <FIG>). The battery is connected to the positioning device <NUM>, so that the positioning device <NUM> can operate even when the engine is stopped.

The communication unit <NUM> is a communication interface for connecting the positioning device <NUM> to the communication network N1 in a wired or wireless manner to execute data communication, according to a predetermined communication protocol, between the communication unit <NUM> and an external device such as the base station <NUM> via the communication network N1.

The antenna <NUM> is an antenna that receives radio waves (GNSS signals) transmitted from satellites. Since the antenna <NUM> is provided at the front and rear parts of the work vehicle <NUM>, the current position and the current orientation of the work vehicle <NUM> can be accurately positioned.

The positioning control unit <NUM> is a computer system including one or more processors and a storage memory such as a non-volatile memory and a RAM. The storage unit <NUM> is a control program for causing the positioning control unit <NUM> to execute the positioning process, and a non-volatile memory for storing data such as positioning information and movement information. The positioning control unit <NUM> positions the current position and the current orientation of the work vehicle <NUM> by a predetermined positioning method (RTK method or the like) based on the GNSS signal received from the satellite <NUM> by the antenna <NUM>.

The obstacle detection device <NUM> includes a LiDAR sensor <NUM> provided on the front and left side of the vehicle body <NUM> and a LiDAR sensor 171R provided on the front and right side of the vehicle body <NUM> (see <FIG>). Each LiDAR sensor measures a distance from the LiDAR sensor to each ranging point (measurement target) in the measurement range by a time of flight (TOF) method for measuring the distance to the ranging point, based on a round-trip time required by laser light input to the LiDAR sensor to reach the ranging point and return to the LiDAR sensor, for example.

The LiDAR sensor <NUM> has a predetermined range on the front and left side of the vehicle body <NUM> set as a measurement range, and the LiDAR sensor 171R has a predetermined range on the front and right side of the vehicle body <NUM> set as a measurement range. Each LiDAR sensor transmits measurement information such as the measured distance to each ranging point and the scanning angle (coordinates) for each ranging point to the vehicle control device <NUM>.

Further, the obstacle detection device <NUM> includes left and right ultrasonic sensors 172F (see <FIG>) provided on the front side of the vehicle body <NUM> and left and right ultrasonic sensors 172R (see <FIG>) provided on the rear side of the vehicle body <NUM>. Each ultrasonic sensor measures a distance from the ultrasonic sensor to a measurement target by the TOF method for measuring a distance to a ranging point, based on a round-trip time from when an ultrasonic wave is transmitted by the ultrasonic sensor to reach the ranging point to when the ultrasonic wave returns.

The ultrasonic sensor 172F on the front and left side has a predetermined range on the front and left side of the vehicle body <NUM> set as the measurement range, the ultrasonic sensor 172F on the front and right side has the predetermined range on the front and right side of the vehicle body <NUM> set as the measurement range, the ultrasonic sensor 172R on the rear and left side has a predetermined range on the rear and left side of the vehicle body <NUM> set as the measurement range, and the ultrasonic sensor 172R on the rear and right side has the predetermined range on the rear and right side of the vehicle body <NUM> set as the measurement range. Each ultrasonic sensor transmits measurement information including the distance to the measurement target and the direction of the object to be measured to the vehicle control device <NUM>.

Further, the obstacle detection device <NUM> includes left and right contact sensors 173F (see <FIG>) provided on the front side of the vehicle body <NUM> and left and right contact sensors 173R (see <FIG>) provided on the rear side of the vehicle body <NUM>. The contact sensor 173F on the front side of the vehicle body <NUM> detects an obstacle when an obstacle comes into contact with the contact sensor 173F. The spray device <NUM> is provided in front of the contact sensor 173R on the rear side of the vehicle body <NUM> (rear side of the work vehicle <NUM>), and when an obstacle comes into contact with the spray device <NUM>, the contact sensor 173R detects the obstacle by the spray device <NUM> moving to the rear (toward the front side of the work vehicle <NUM>). Each contact sensor transmits a detection signal to the vehicle control device <NUM> when an obstacle is detected.

The vehicle control device <NUM> executes an avoidance process for avoiding an obstacle when the work vehicle <NUM> may collide with the obstacle based on the measurement information about the obstacle acquired from the obstacle detection device <NUM>.

Further, the vehicle control device <NUM> detects a position deviation and an orientation deviation of the work vehicle <NUM> to perform an operation (correction operation) to avoid a collision with the crop rows Vr.

For example, the travel processing unit <NUM> moves the work vehicle <NUM> from the work route R1 of the crop row Vra to the work route R1 of the crop row Vrb according to the target route R illustrated in <FIG>. When reaching the end point P0 of the crop row Vra, the work vehicle <NUM> stops the spraying, travels straight on a straight route r1, and starts turning at a turning start position P1. When starting the turning, the work vehicle <NUM> moves from a turning route r2, then a straight route r3, to a turning route r4, travels straight from a turn end position P4 to a straight route r5, and moves to an end point P0 of a crop row Vrb being a next work route R1 to resume spraying. In <FIG>, reference symbol C1 indicates a turning center of the turning route r2, and reference symbol C2 indicates a turning center of the turning route r4. Turning radii of the turning routes r2 and r4 are the same.

The detection processing unit <NUM> of the vehicle control device <NUM> detects the position deviation and the orientation deviation of the work vehicle <NUM> traveling automatically. Specifically, the detection processing unit <NUM> detects the position deviation and the orientation deviation of the work vehicle <NUM> with respect to the target route R, based on the positioning information (a current position and a current orientation) from the positioning device <NUM>.

The correction processing unit <NUM> of the vehicle control device <NUM> determines whether the position deviation detected by the detection processing unit <NUM> exceeds a previously set threshold value (position threshold value). The correction processing unit <NUM> executes a correction operation for correcting the position deviation if the position deviation exceeds a position threshold value. Further, the correction processing unit <NUM> determines whether the orientation deviation detected by the detection processing unit <NUM> exceeds a previously set threshold value (orientation threshold value). The correction processing unit <NUM> executes a correction operation for correcting the orientation deviation if the orientation deviation exceeds an orientation threshold value. The position threshold value and the orientation threshold value are set previously in, for example, the operation terminal <NUM>. Each of the position threshold value and the orientation threshold value is an example of a threshold value of the present invention. The correction processing unit <NUM> is an example of a correction processing unit according to the present invention.

An example of the correction operation will be described now with reference to <FIG> illustrates a part of the target route R including the turning route r4 and the straight route r5, which are illustrated in <FIG>. For example, if the work vehicle <NUM> deviates from the turning route r4 of the target route R, and at a position P5 of a distance m1 (position deviation) from a target turning end position P4, a position deviation m1 exceeds the position threshold value and an orientation deviation θa exceeds the orientation threshold value, the correction processing unit <NUM> executes the following correction operation. Firstly, the correction processing unit <NUM> causes the work vehicle <NUM> to spin-turn (neutrally turn) at the position P5 until the orientation deviation θa of the work vehicle <NUM> with respect to the direction of a straight line connecting the position P5 and a position P6 on the extended line of the straight route r5 is equal to or less than the orientation threshold value.

Next, the correction processing unit <NUM> causes the work vehicle <NUM> to travel backward until the work vehicle <NUM> reaches the position P6 or until the position deviation m1 of the work vehicle <NUM> with respect to the extended line of the straight route r5 is equal to or less than the position threshold value. It is noted that the target position of the position P6 is a position which is at a distance m2 (for example, <NUM>) from the turning end position P4.

Next, the correction processing unit <NUM> causes the work vehicle <NUM> to spin-turn (neutrally turn), for example, at the position P6 until the orientation deviation of the work vehicle <NUM> with respect to the direction of the extended line of the straight route r5 is equal to or less than the orientation threshold value. Next, the correction processing unit <NUM> causes the work vehicle <NUM> to travel straight from the position P6 to the turning end position P4 along the extended line of the straight route r5. After that, the travel processing unit <NUM> causes the work vehicle <NUM> to travel straight on the straight route r5 and enter the work route R1 of the crop row Vrb from the end point P0.

The correction processing unit <NUM> executes the correction operation every time the position deviation exceeds the position threshold value, and executes the correction operation every time the orientation deviation exceeds the orientation threshold value. Therefore, as in the conventional case, if the threshold value (the position threshold value or the orientation threshold value) is uniformly fixed, for example, for example, when a condition of the farm field F (topsoil) is not good and when the farm field F is sloped, as a result of the deviation (the position deviation or the orientation deviation) frequently exceeding the threshold value, the correction operation is repeatedly executed. This causes a problem that the work efficiency of spraying work with the work vehicle <NUM> is reduced. On the other hand, in the work vehicle <NUM> according to the present embodiment, if the correction operation is prevented from being repeatedly executed, it is possible to improve the work efficiency of the spraying work.

Specifically, the setting processing unit <NUM> of the vehicle control device <NUM> changeably sets the threshold value of at least one of the position deviation and the orientation deviation of the work vehicle <NUM> with respect to the target route R. For example, the setting processing unit <NUM> changes the position threshold value and orientation threshold value previously set, based on travel history information of the work vehicle <NUM>. The setting processing unit <NUM> is an example of a setting processing unit according to the present invention.

Specifically, firstly, the setting processing unit <NUM> sets an initial value (a position initial value and an orientation initial value) of each of the position deviation and the orientation deviation with respect to the work route R1. The initial value is, for example, a setting value (design value) at the time of shipment from the factory, and is determined based on a width of the corresponding crop row Vr, the position control accuracy of the work vehicle <NUM>, and the like. Next, the travel processing unit <NUM> causes the work vehicle <NUM> to execute the spraying work while causing the work vehicle <NUM> to automatically travel according to the target route R. While the work vehicle <NUM> automatically traveling, the detection processing unit <NUM> calculates and records a maximum change amount Pm of the position deviation with respect to the position initial value and a maximum change amount Dm of the orientation deviation with respect to the orientation initial value, for each of the plurality of work routes R1 (see <FIG>) included in the target route R, in a region within a predetermined distance from the end point P0 on a side entering the work route R1. The detection processing unit <NUM> calculates, an allowable position deviation level Lp corresponding to the maximum change amount Pm and an allowable orientation deviation level Ld corresponding to the maximum change amount Dm, for each work route R1. The allowable position deviation level Lp is an index representing a level (stage) at which the position deviation is allowable, which does not require the above-mentioned correction operation for the work route R1, and the allowable orientation deviation level Ld is an index representing a level (stage) at which the orientation deviation is allowable, which does not require the above-mentioned correction operation for the work route R1.

The detection processing unit <NUM> executes automatic travel and the spraying work to store the position deviation information F1 obtained by recording the maximum change amount Pm and the allowable position deviation level Lp in an associated manner for each work route R1 and the orientation deviation information F2 obtained by recording the maximum change amount Dm and the allowable orientation deviation level Ld in an associated manner for each work route R1, into the storage unit <NUM>. <FIG> is a table showing an example of the position deviation information F1 and <FIG> is a table showing an example of the orientation deviation information F2. Each of the position deviation information F1 and the orientation deviation information F2 is an example of travel history information according to the present invention.

The setting processing unit <NUM> changes the position threshold value and orientation threshold value previously set, based on the past position deviation information F1 and orientation deviation information F2 recorded by the detection processing unit <NUM>. Specifically, the setting processing unit <NUM> determines, for each work route R1, a position offset amount Op with respect to the position threshold value and an orientation offset amount Od with respect to the orientation threshold value. The position offset amount Op is correction information of the previously set position threshold value and the orientation offset amount Od is correction information of the previously set orientation threshold value. The storage unit <NUM> previously stores position correction information F3 indicating a position offset amount Op corresponding to the allowable position deviation level Lp (see <FIG>) and orientation correction information F4 indicating an orientation offset amount Od corresponding to the allowable orientation deviation level Ld (see <FIG>). The setting processing unit <NUM> refers to the position correction information F3 to determine the position offset amount Op for the position threshold value for each work route R1, and refers to the orientation correction information F4 to determine the orientation offset amount Od for the orientation threshold value for each work route R1.

The setting processing unit <NUM> sets a value obtained by adding or subtracting the position offset amount Op to or from the previously set position threshold value as the position threshold value for the next spraying work. The setting processing unit <NUM> sets a value obtained by adding or subtracting the orientation offset amount Od to or from the previously set orientation threshold value as the orientation threshold value for the next spraying work. For example, the setting processing unit <NUM> acquires an allowable position deviation level Lp1 of the crop row Vr1 by referring to the position deviation information F1 being the travel history information acquired when the work vehicle <NUM> travels last time, acquires a position offset amount Op1 corresponding to the allowable position deviation level Lp1 by referring to the position correction information F3, and changes the previously set position threshold value by the position offset amount Op1. For example, the setting processing unit <NUM> acquires an allowable orientation deviation level Ld1 of the crop row Vr1 by referring to the orientation deviation information F2 being the travel history information acquired when the work vehicle <NUM> travels last time, acquires an orientation offset amount Op1 corresponding to the allowable orientation deviation level Ld1 by referring to the orientation correction information F4, and changes the previously set orientation threshold value by the position offset amount Op1.

As described above, the setting processing unit <NUM> changes the threshold values (the position threshold value and the orientation threshold value) for each of the work routes R1, based on the deviations (the position deviation and the orientation deviation) for the work route R1, for each of the work routes R1, the deviations being included in the travel history information. The setting processing unit <NUM> may change the threshold value of a first work route R1 and the threshold value of a second work route R1 to values different from each other.

It is noted that, in <FIG> and <FIG>, for convenience, the allowable position deviation level Lp and the position offset amount Op are indicated at <NUM> stages (Lp1 to Lp11, Op1 to Op11) according to the number of work routes, but in reality, may be represented at a previously set number of stages (for example, three stages). Likewise, in <FIG> and <FIG>, for convenience, the allowable orientation deviation level Ld and the orientation offset amount Od are indicated at <NUM> stages (Ld1 to Ld11, Od1 to Od11) according to the number of work routes, but in reality, may be represented at a previously set number of stages (for example, three stages).

The route data transferred from the operation terminal <NUM> includes information on the target route R, an area for storing the maximum change amounts Pm, Dm, and an area for storing the allowable position deviation level Lp and the allowable orientation deviation level Ld. Further, in the route data transferred from the operation terminal <NUM>, the allowable position deviation level Lp and the allowable orientation deviation level Ld are set to a lowest value (level equivalent to an allowable deviation of <NUM>). The vehicle control device <NUM> causes the work vehicle <NUM> to automatically travel based on the route data, and calculates the allowable position deviation level Lp and the allowable orientation deviation level Ld to update the route data. That is, the route data where the position deviation information F1 (see <FIG>) and the orientation deviation information F2 (see <FIG>) are associated is stored in the storage unit <NUM>. The position correction information F3 and the orientation correction information F4 may be previously stored in the storage unit <NUM>, or may be included in the route data transferred from the operation terminal <NUM>. The travel processing unit <NUM> executes the next automatic travel and spraying work, based on the updated route data.

As another embodiment, the setting processing unit <NUM> may change, based on the travel history information of the work vehicle <NUM>, the previously set position threshold value and orientation threshold value, for each farm field F. For example, the detection processing unit <NUM> calculates one maximum change amount Pm, Dm for all the work routes R1 corresponding to the crop rows Vr1 to Vr11, one allowable position deviation level Lp, and one allowable orientation deviation level Ld. As a result, the setting processing unit <NUM> determines one position offset amount Op and one orientation offset amount Od with respect to the farm field F to set the position threshold value and the orientation threshold value.

In the above example, the maximum change amounts of the position deviation and the orientation deviation are used, but in another embodiment, a probability statistical method may be used to utilize a method of calculating the allowable deviation level, based on variance values of deviations.

With the above configuration, it is possible to change the threshold value of the position deviation and the orientation deviation, and thus, it is possible to avoid an unnecessary correction operation of the work vehicle <NUM>. Therefore, it is possible to increase the work efficiency of the spraying work of the work vehicle <NUM>. Further, it is possible to use the history information obtained by actually traveling in the farm field F, and thus, it is possible to set the threshold value to an appropriate value suitable for the farm field F. Therefore, it is also possible to improve the work accuracy.

In another embodiment, the setting processing unit <NUM> may change the threshold value of the deviation with respect to an entering position (end point P0) at which the work vehicle <NUM> enters the work route R1. For example, the work accuracy of the spraying work by the work vehicle <NUM> is easily affected by the magnitude of the position deviation and the orientation deviation at the end point P0 at which the work vehicle <NUM> enters the work route R1, and as the position deviation and the orientation deviation at the end point P0 are smaller, the work accuracy is improved. Therefore, configuration may be that the setting processing unit <NUM> changes the threshold value of the deviations (the positional deviation and the orientation deviation) with respect to the end point P0 on the entering side of the work route R1 and does not change the threshold value of the deviations (the position deviation and the orientation deviation) within the work route R1.

Further, the setting processing unit <NUM> may change the threshold value of the deviation with respect to the entering position of the work route R1 to a value smaller than the threshold value of the deviation within the work route R1. Thus, when the threshold value of the deviations (the position deviation and the orientation deviation) with respect to the end point P0 on the entering side of the work route R1 is reduced (set strictly), it is possible to appropriately set the position and the orientation of the work vehicle <NUM> when entering the work route R1. Further, when the threshold value of the deviations within the work route R1 is increased (set roughly), it is possible to suppress the correction operation within the work route R1. Therefore, it is possible to increase the work efficiency of the spraying work of the work vehicle <NUM>.

The above-described configuration of the work vehicle <NUM> is an example of the configuration of the work vehicle according to the present invention, and the present invention is not limited to the above-described configuration. The above-mentioned work vehicle <NUM> is a vehicle capable of performing the spraying work for spraying the spraying material to the first crop row Vr and the second crop row Vr in each of the left-right direction of the first crop row Vr while traveling across the first crop row Vr. In another embodiment, the vehicle body <NUM> of the work vehicle <NUM> may have a typical shape instead of the inverted U-shape, so that the vehicle body <NUM> entirely travels between the crop rows Vr (work passages). In this case, the work vehicle <NUM> automatically travels sequentially on each work passage, without spanning over the crop rows Vr. The spray device <NUM> is provided with one spraying unit and performs a spraying work while switching between a spraying pattern in which the chemical liquid is sprayed in both left and right directions, a spraying pattern in which the chemical liquid is sprayed only in the left direction, and a spraying pattern in which the chemical liquid is sprayed only in the right direction.

As illustrated in <FIG>, the operation terminal <NUM> is an information processing device including a control unit <NUM>, a storage unit <NUM>, an operation display unit <NUM>, and a communication unit <NUM>. The operation terminal <NUM> may be composed of a mobile terminal such as a tablet terminal or a smartphone.

The communication unit <NUM> is a communication interface for connecting the operation terminal <NUM> to the communication network N1 in a wired or wireless manner to execute data communication according to a predetermined communication protocol between the operation terminal <NUM> and an external device such as one or more work vehicles <NUM> via the communication network N1.

The operation display unit <NUM> is a user interface including a display unit such as a liquid crystal display or an organic EL display that displays various types of information, and an operation unit such as a mouse, a keyboard, or a touch panel that receives an operation. On the operation screen displayed on the display unit, the operator can operate the operation unit to register various types of information (work vehicle information, farm field information, work information, etc., which will be described later). Further, the operator can operate the operation unit to give a work start instruction, a travel stop instruction, and the like to the work vehicle <NUM>. At a place away from the work vehicle <NUM>, the operator is capable of grasping the travel state, a work situation, and a surrounding situation of the work vehicle <NUM> automatically traveling according to the target route R within the farm field F, based on a travel trajectory displayed on the operation terminal <NUM> and a surrounding image of the vehicle body <NUM>.

The storage unit <NUM> is a non-volatile storage unit, such as an HDD or an SSD that stores various types of information. The storage unit <NUM> stores a control program such as an automatic traveling program for causing the control unit <NUM> to execute an automatic traveling process (see <FIG> and <FIG>) described later. For example, the automatic traveling program is recorded non-temporarily on a computer-readable recording medium such as a CD or a DVD, and is read by a predetermined reading device (not illustrated) to be stored in the storage unit <NUM>. The automatic traveling program may be downloaded from a server (not illustrated) to the operation terminal <NUM> via the communication network N1 and stored in the storage unit <NUM>.

The control unit <NUM> includes control devices such as a CPU, a ROM, and a RAM. The CPU is a processor that executes various types of arithmetic processes. The ROM is a non-volatile storage unit in which a control program such as BIOS and OS for causing the CPU to execute various types of arithmetic processes is stored in advance. The RAM is a volatile or non-volatile storage unit that stores various types of information, and is used as a temporary storage memory (working area) for various types of processes executed by the CPU. The control unit <NUM> controls the operation terminal <NUM> by causing the CPU to execute various types of control programs stored in advance in the ROM or the storage unit <NUM>.

As illustrated in <FIG>, the control unit <NUM> includes various types of processing units such as a setting processing unit <NUM>, a route generation processing unit <NUM>, and an output processing unit <NUM>. The control unit <NUM> functions as the various types of processing units by causing the CPU to execute various types of processes according to the control programs. Some or all of the processing units may be configured by an electronic circuit. The control programs may be programs for causing a plurality of processors to function as the processing units.

The setting processing unit <NUM> sets and registers information on the work vehicle <NUM> (hereinafter referred to as work vehicle information), information on the farm field F (hereinafter referred to as farm field information), and information on work (here, a spraying work) (hereinafter, work information).

In the setting process of the work vehicle information, the setting processing unit <NUM> sets information about the model of the work vehicle <NUM>, the position where the antenna <NUM> is attached in the work vehicle <NUM>, kinds of the work machine (here, the spraying device <NUM>), the size and the shape of the work machine, the position of the work machine relative to the work vehicle <NUM>, a vehicle speed and an engine RPM of the work vehicle <NUM> during working, a vehicle speed and an engine RPM of the work vehicle <NUM> during turning, and the like as a result of the operator operating for registering such information on the operation terminal <NUM>. In the present embodiment, information about the spray device <NUM> is set as the information of the working machine.

In the setting process of the farm field information, the setting processing unit <NUM> sets information about the position and the shape of the farm field F, the work start position S to start the work and the work end position G to end the work (see <FIG>), a working direction, and the like, as a result of the operator operating for registering such information on the operation terminal <NUM>. The working direction means a direction in which the work vehicle <NUM> travels while performing the spraying work by the spray device <NUM> in the working area which is the area excluding the non-work region such as the headland from the farm field F.

It is possible to automatically obtain the information about the position and the shape of the farm field F when the operator manually causes the work vehicle <NUM> to encircle along the outer perimeter of the farm field F, for example, and a transition of the position information of the antenna <NUM> at that time is recorded. It is also possible to obtain the position and the shape of the farm field F, based on a polygon obtained by the operator operating the operation terminal <NUM> in a state where a map is displayed on the operation terminal <NUM> and designating a plurality of points on the map. A region designated by the obtained position and shape of the farm field F is a region (travel region) where the work vehicle <NUM> can travel.

In the setting process of the work information, as the work information, the setting processing unit <NUM> is configured to be set with a skipped number being the number of work routes to be skipped if the work vehicle <NUM> turns in the headland, a width of the headland, and the like.

The route generation processing unit <NUM> generates a target route R being a route on which the work vehicle <NUM> automatically travels, based on each of the setting information. The target route R is, for example, a route from the work start position S to the work end position G (see <FIG>). The target route R illustrated in <FIG> includes a linear work route R1 for spraying the chemical liquid to the crop V in the region where the crop V is planted, and a movement route R2 for moving between the crop rows Vr without performing the spraying work.

An example of a method of generating the target route R will be described with reference to <FIG> schematically illustrates the crop rows Vr. Firstly, the operator manually causes the work vehicle <NUM> to travel along the outer perimeter of the crop rows Vr (see <FIG>). While traveling, the work vehicle <NUM> detects end points E1 on one side (lower side in <FIG>) and end points E2 on the other side (upper side in <FIG>) of the crop rows Vr, and acquires position information (coordinates) of each of the end points E1 and E2. The end points E1 and E2 may be positions of crops V that are already planted, or may be positions of target objects indicating positions of crops V that are to be planted. When acquiring the position information (coordinates) of each of the end points E1 and E2 from the work vehicle <NUM>, the route generation processing unit <NUM> sets lines L1 (see <FIG>) connecting corresponding ones of the end points E1 and E2 as work routes of the crop rows Vr, to generate the target route R including a plurality of the work routes and movement routes (turning routes). The method of generating the target route R is not limited to the method described above. The route generation processing unit <NUM> may store the generated target route R in the storage unit <NUM>.

The output processing unit <NUM> outputs, to the work vehicle <NUM>, route data including information about the target route R generated by the route generation processing unit <NUM>. The route data includes an area for storing the maximum change amounts Pm and Dm for each work route R1 and an area for storing the allowable position deviation level Lp and the allowable orientation deviation level Ld. An initial value (the lowest value at which the allowable deviation is equivalent to <NUM>) is registered for the allowable position deviation level Lp and the allowable orientation deviation level Ld of the route data.

The output processing unit <NUM> may output the route data to a server (not illustrated). The server stores and manages a plurality of the route data acquired from each of the plurality of operation terminals <NUM> in association with the operation terminal <NUM> and the work vehicle <NUM>.

In addition to the above-described processes, the control unit <NUM> executes a process for causing the operation display unit <NUM> to display various types of information. For example, the control unit <NUM> causes the operation display unit <NUM> to display a registration screen for registering work vehicle information, farm field information, work information, and the like, an operation screen for generating the target route R, an operation screen for causing the work vehicle <NUM> to start automatic travel, a display screen for displaying a travel state of the work vehicle <NUM>, and the like.

Further, the control unit <NUM> receives various types of operations from the operator. Specifically, the control unit <NUM> receives a work start instruction from the operator to cause the work vehicle <NUM> to start a work, a travel stop instruction to stop the traveling of the work vehicle <NUM> traveling automatically, and the like. When the control unit <NUM> receives each of the instructions, the control unit <NUM> outputs each of the instructions to the work vehicle <NUM>.

When the vehicle control device <NUM> of the work vehicle <NUM> acquires the work start instruction from the operation terminal <NUM>, the vehicle control device <NUM> starts the automatic traveling and a spraying work of the work vehicle <NUM>. When the vehicle control device <NUM> acquires the travel stop instruction from the operation terminal <NUM>, the vehicle control device <NUM> stops the automatic traveling and spraying work of the work vehicle <NUM>.

The operation terminal <NUM> may be accessible to the website (agricultural support site) of the agricultural support service provided by the server via the communication network N1. In this case, the operation terminal <NUM> is capable of functioning as an operation terminal of the server as a result of the browser program being executed by the control unit <NUM>.

An example of the automatic traveling process executed by the vehicle control device <NUM> of the work vehicle <NUM> and the control unit <NUM> of the operation terminal <NUM> will be described below with reference to <FIG> and <FIG>. <FIG> is a flowchart illustrating an example of a threshold value setting process for setting the threshold value (the position threshold value and the orientation threshold value).

The present invention may be regarded as an invention of an automatic traveling method in which one or more steps included in the automatic traveling process are executed. Further, one or more steps included in the automatic traveling process described herein may be omitted where appropriate. In addition, the steps in the automatic traveling process may be executed in a different order as long as a similar operation and effect are obtained. Here, a case where each of the steps in the automatic traveling process is executed by the vehicle control device <NUM> and the control unit <NUM> is described by way of example. However, another embodiment may be an automatic traveling method in which the steps in the automatic traveling process are executed in a distributed manner by one or more processors.

In step S1 illustrated in <FIG>, the vehicle control device <NUM> sets the initial values (the position initial value and the orientation initial value) of the position deviation and the orientation deviation. Next, in step S2, the vehicle control device <NUM> starts the automatic travel according to the target route R (see <FIG>).

Next, in step S3, while the work vehicle <NUM> automatically travels, the vehicle control device <NUM> calculates and records a maximum change amount Pm of the position deviation with respect to the position initial value and a maximum change amount Dm of the orientation deviation with respect to the orientation initial value, for each of the plurality of work routes R1 (see <FIG>) included in the target route R, in a region within a predetermined distance from the end point P0 when entering the work route R1.

Next, in step S4, the vehicle control device <NUM> calculates, an allowable position deviation level Lp corresponding to the maximum change amount Pm and an allowable orientation deviation level Ld corresponding to the maximum change amount Dm, for each work route R1.

The vehicle control device <NUM> stores the position deviation information F1 (see <FIG>) obtained by recording the maximum change amount Pm and the allowable position deviation level Lp in an associated manner, for each work route R1 (crop row Vr), and the orientation deviation information F2 (see <FIG>) obtained by recording the maximum change amount Dm and the allowable orientation deviation level Ld in an associated manner, for each work route R1 (crop row Vr), into the storage unit <NUM>.

Next, in step S5, the vehicle control device <NUM> determines, for each work route R1, a position offset amount Op with respect to the position threshold value and an orientation offset amount Od with respect to the orientation threshold value. Specifically, the vehicle control device <NUM> refers to the position correction information F3 (see <FIG>) to determine the position offset amount Op corresponding to the allowable position deviation level Lp, for each work route R1, and refers to the orientation correction information F4 (see <FIG>) to determine the orientation offset amount Od corresponding to the allowable orientation deviation level Ld, for each work route R1.

Finally, in step S6, the vehicle control device <NUM> sets a value obtained by adding or subtracting the position offset amount Op to or from the previously set position threshold value as a position threshold value for the next spraying work. The vehicle control device <NUM> sets a value obtained by adding or subtracting the orientation offset amount Od to or from the previously set orientation threshold value as the orientation threshold value for the next spraying work.

As described above, the vehicle control device <NUM> utilizes the past (for example, previous) travel history information to set the position threshold value and the orientation threshold value utilized for the next automatic travel and spraying work. The vehicle control device <NUM> may change the position threshold value and the orientation threshold value each time the work vehicle <NUM> travels in the farm field F, or may change the position threshold value and the orientation threshold value each time the work vehicle <NUM> travels the farm field F a plurality of predetermined numbers of times.

When setting the position threshold value and the orientation threshold value, the vehicle control device <NUM> executes the following automatic traveling process, in the next automatic travel and spraying work, for example.

In step S11 of <FIG>, the vehicle control device <NUM> determines whether a work start instruction has been acquired from the operation terminal <NUM>. For example, when an operator depresses a start button on the operation terminal <NUM>, the operation terminal <NUM> outputs the work start instruction to the work vehicle <NUM>. When the vehicle control device <NUM> acquires the work start instruction from the operation terminal <NUM> (S11: Yes), the process proceeds to step S12. The vehicle control device <NUM> waits until the work start instruction is acquired from the operation terminal <NUM> (S11: No).

In step S12, the vehicle control device <NUM> starts the automatic travel. For example, when acquiring the work start instruction and the route data from the operation terminal <NUM>, the vehicle control device <NUM> starts the automatic travel along the target route R corresponding to the route data. The vehicle control device <NUM> stores the route data acquired from the operation terminal <NUM> into the storage unit <NUM>.

Next, in step S13, the vehicle control device <NUM> determines whether at least one of the position deviation and the orientation deviation exceeds the threshold value (the position threshold value and the orientation threshold value). Specifically, the vehicle control device <NUM> detects the position deviation and the orientation deviation of the work vehicle <NUM> with respect to the target route R, based on the positioning information (the current position and the current orientation) by the positioning device <NUM>. The vehicle control device <NUM> determines whether the detected position deviation exceeds the position threshold value set in the threshold value setting process (see <FIG>) and whether the detected orientation deviation exceeds the orientation threshold value set in the threshold value setting process (see <FIG>). If the position deviation exceeds the position threshold value (S13: Yes), or if the orientation deviation exceeds the orientation threshold value (S13: Yes), the process proceeds to step S131. If the position deviation is equal to or less than the position threshold value and the orientation deviation is equal to or less than the orientation threshold value (S13: No), the process proceeds to step S14.

In step S131, the vehicle control device <NUM> executes the correction operation for correcting the deviations (the position deviation and the orientation deviation) of the work vehicle <NUM>. For example, if the position deviation exceeds the position threshold value and the orientation deviation exceeds the orientation threshold value, the vehicle control device <NUM> performs the neutral turn illustrated in <FIG> and moves backward to correct the posture of the work vehicle <NUM>. After the correction operation is performed, the process returns to step S13, and the vehicle control device <NUM> restarts the automatic travel and spraying work and executes the above-mentioned determination process.

In step S14, the vehicle control device <NUM> determines whether the work vehicle <NUM> has ended the work. The vehicle control device <NUM> determines that the work is completed when the position of the work vehicle <NUM> coincides with the work end position G. When the work vehicle <NUM> completes the work (S14: Yes), the automatic traveling process ends. The vehicle control device <NUM> repeats the determination process in step S13 and the correction operation until the work vehicle <NUM> completes the work to continue the automatic travel.

As described above, the automatic traveling system <NUM> according to the present embodiment causes the work vehicle <NUM> to automatically travel according to the target route R in a work area (for example, the farm field F) and changeably sets the threshold value of the deviation including at least one of the position deviation and the orientation deviation of the work vehicle <NUM> with respect to the target route R. Further, the automatic traveling system <NUM> causes the work vehicle <NUM> to execute the correction operation for correcting the deviation if the deviation exceeds the threshold value. Further, in the automatic traveling method according to the present embodiment, one or more processors execute causing the work vehicle <NUM> to automatically travel according to the target route R in the work area (the farm field F, for example), changeably setting the threshold value of the deviation including at least one of the position deviation and the orientation deviation of the work vehicle <NUM> with respect to the target route R, and causing the work vehicle <NUM> to execute a correction operation for correcting the deviation if the deviation exceeds the threshold value. Further, in the threshold value setting method according to the present embodiment, the threshold value of the deviation including at least one of the position deviation and the orientation deviation of the work vehicle <NUM> with respect to the target route R is changeably set.

According to the above configuration, it is possible to set the threshold value of the position deviation (deviation in position) or the orientation deviation (deviation in orientation) for the target route R to a value according to the farm field F or the work route R1. As a result, it is possible to prevent the deviation from exceeding the threshold value at a place where the correction operation is not required, and thus, it is possible to suppress an unnecessary correction operation. Therefore, it is possible to increase the work efficiency of the work by the work vehicle <NUM>.

The present invention is not limited to the embodiments described above. Other embodiments of the present invention will be described below.

In the above-described embodiment, the setting processing unit <NUM> changes the position threshold value and the orientation threshold value, based on the travel history information (the position deviation information F1 and the orientation deviation information F2) of the work vehicle <NUM>. On the other hand, in another embodiment, the setting processing unit <NUM> may set the threshold values, based on slope information indicating a slope of the farm field F. Specifically, as illustrated in <FIG>, if the farm field F is sloped in the lateral direction (direction in which the crop rows are arranged) by an angle θ3 and sloped by an angle θ4 in the vertical direction (work route direction), the setting processing unit <NUM> calculates the allowable position deviation level and the allowable orientation deviation level, based on the slope angles θ3 and θ4. It is noted that the slope angles θ3 and θ4 are calculated according to the following equation using end points n0 (x0, y0, z0), n1 (x1, y1, z1), and n2 (x2, y2, z2) of the crop rows Vr illustrated in <FIG>. <NUM>] <MAT>
[Math. <NUM>] <MAT>.

For example, the setting processing unit <NUM> previously creates a map function from test data obtained by an actual machine or test data obtained through a simulation, and calculates the allowable position deviation level and the allowable orientation deviation level according to the slope angles θ3 and θ4 by using the map function. The setting processing unit <NUM> sets, based on the position offset amount Op and the orientation offset amount Od corresponding to the calculated allowable position deviation level and allowable orientation deviation level, the position threshold value and the orientation threshold value.

Thus, the setting processing unit <NUM> calculates the slope of the farm field F, based on altitude information (z coordinate information) indicating the altitude of the end point P0 of the work route R1.

According to such a configuration, the allowable position deviation level and the allowable orientation deviation level are calculated at the time of creating the map of the farm field F, and thus, it is not necessary to calculate the maximum change amounts Pm, Dm, the allowable position deviation level Lp, and the allowable orientation deviation level Ld during the automatic travel of the work vehicle <NUM>. Therefore, it is possible to reduce the processing load of the work vehicle <NUM> during automatic travel.

It is noted that in the above configuration, the control unit <NUM> of the operation terminal <NUM> may calculate the allowable position deviation level and the allowable orientation deviation level, and determine the position offset amount Op and the orientation offset amount Od corresponding to the calculated allowable position deviation level and allowable orientation deviation level, which are set to the position threshold value and the orientation threshold value. In this case, the position correction information F3 and the orientation correction information F4 are recorded in the storage unit <NUM> of the operation terminal <NUM>. The control unit <NUM> transfers the route data including the target route R, the position threshold value, and the orientation threshold value to the work vehicle <NUM>.

In another embodiment of the present invention, the setting processing unit <NUM> may set the threshold value, based on a topsoil condition of the farm field F. Specifically, the setting processing unit <NUM> determines, based on an image captured by a camera (not illustrated) mounted on the work vehicle <NUM>, a detection result by another external sensor (not illustrated), and the like, the topsoil state (road surface state) of the farm field F, and dynamically determines the allowable position deviation level and the allowable orientation deviation level, based on the determination result. It is noted that, if the image captured by the camera is used, the setting processing unit <NUM> may calculate the allowable position deviation level and the allowable orientation deviation level from image data by using a deep learning method (End to End learning).

If using a three-dimensional sensor as the external sensor, the setting processing unit <NUM> may measure the slope angle of a road surface, unevenness of the road surface, and the like, and calculate the allowable position deviation level and the allowable orientation deviation level by using a conversion function set in advance. It is noted that, in the method using the external sensor, it is possible to dynamically set the position threshold value and the orientation threshold value before the vehicle enters the crop row Vr without having traveled in the farm field F, and it is also possible to respond to sudden changes in road surface conditions from the previous travel.

A reference embodiment of the automatic traveling system <NUM> according to the present embodiment will be described below. The automatic traveling system <NUM> may include a configuration described in the following reference embodiment.

<FIG> illustrates a state where in the work vehicle <NUM> traveling automatically, a position deviation from a turning route r4 of the target route R by a distance L11 is generated and an orientation deviation by an angle θ1 is generated.

Here, if a distance L12 from an extended line of a route (straight route r5) subsequent to the turning route r4 is smaller than a position deviation L11 and the distance L12 is equal to or less than a position threshold value, the vehicle control device <NUM> controls the work vehicle <NUM> to stop the turning operation along the turning route r4 and to transition to an operation for moving to a turning end position P4 along the extended line and an operation for moving straight along the straight route r5. It is noted that a condition for moving from the turning operation to a next moving-straight operation may include a condition that "the angle θ2 of the work vehicle <NUM> with respect to the extended line of the route (straight route r5) subsequent to the turning route r4 is smaller than the orientation deviation θ1. " When such a condition is included, the work vehicle <NUM> can transition to the next moving-straight operation without performing the neutral turn operation.

According to the above configuration, even if the position deviation and the orientation deviation with respect to the route on which the work vehicle <NUM> travels are large, when the position deviation and the orientation deviation with respect to the next route are small, the work vehicle <NUM> terminates the operation for the route on which the work vehicle <NUM> travels and transitions to the operation for the next route, and thus, it is possible to continue the travel operation while suppressing an unnecessary correction operation. Therefore, it is possible to improve the work efficiency of the work vehicle <NUM>.

Claim 1:
An automatic traveling method, comprising:
causing a work vehicle (<NUM>) to automatically travel according to a target route (R) in a work area (F) where crops (V) are planted;
changeably setting, with respect to the target route (R), a threshold value of a deviation including at least one of a position deviation and an orientation deviation of the work vehicle (<NUM>); and
causing the work vehicle (<NUM>) to execute a correction operation for correcting the deviation if the deviation exceeds the threshold value, to avoid collision against the crops (V) during automatic travelling.