Patent Description:
In recent years, progress in automation technology for agricultural machinery has led to introduction of a work vehicle that performs a work, while automatically traveling within a field. Conventionally, there is known a technique that allows a work vehicle to automatically travel along a shape of a field in an outer peripheral area of the field (see, for example, Patent Document <NUM>). Further, Patent Document <NUM> discloses a travel route management system of working machine.

Herein, in a case where a work machine is caused to automatically travel in an outer peripheral area of a field, for example, a distance between a ridge located on an outer periphery of the field and the work vehicle becomes close, and the work vehicle may come into contact with the ridge. Therefore, in the conventional art, a target route on the outermost periphery is set at a position away from the ridge by a predetermined distance. This makes it impossible for the work vehicle to automatically travel in the vicinity of the ridge, which may cause a problem that work efficiency is lowered.

An object of the present invention is to provide an automatic traveling method, an automatic traveling system, and an automatic traveling program that can improve work efficiency of a work vehicle in an outer peripheral area of a field.

An automatic traveling method according to the present invention, an automatic traveling system according to the invention and an automatic traveling program according to the present invention are defined in the appended claims. The automatic traveling method includes: causing a work vehicle to automatically travel along a target route set within a field; detecting an obstacle located on an outer periphery of the field, while the work vehicle is traveling along the target route in an outer peripheral area of the field; and, in a case where the obstacle is an object to be avoided, causing the work vehicle to travel along an avoidance route that is located more inside the field than the target route.

An automatic traveling system according to the present invention includes: a traveling processing unit that causes a work vehicle to automatically travel along a target route set within a field; and a detection processing unit that detects an obstacle located on an outer periphery of the field, while the work vehicle is traveling along the target route in an outer peripheral area of the field. In a case where the obstacle is an object to be avoided, the traveling processing unit causes the work vehicle to travel along an avoidance route that is located more inside the field than the target route.

An automatic traveling program according to the present invention is an automatic traveling program causing one or more processors to execute: causing a work vehicle to automatically travel along a target route set within a field: detecting an obstacle located on an outer periphery of the field, while the work vehicle is traveling along the target route in an outer peripheral area of the field; and, in a case where the obstacle is an object to be avoided, causing the work vehicle to travel along an avoidance route that is located more inside the field than the target route.

According to the present invention, it is possible to provide an automatic traveling method, an automatic traveling system, and an automatic traveling program that can improve work efficiency of a work vehicle in an outer peripheral area of a field.

The following embodiments are an example embodying the present invention, and are not intended to limit the technical scope of the present invention.

As illustrated in <FIG>, an automatic traveling system <NUM> according to an embodiment of the present invention includes a work vehicle <NUM> and an operation terminal <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 with each other via a mobile phone network, a packet network, or a wireless LAN.

In the present embodiment, a case in which the work vehicle <NUM> is a rice transplanter is described as an example. Note that, as another embodiment, the work vehicle <NUM> may be a tractor, a combine harvester, a construction machine, a snow plow, or the like. The work vehicle <NUM> is an automatic traveling vehicle provided with a configuration that enables to automatically travel (autonomously travel) within a field registered in advance. For example, an operator registers a field as a work target, and sets a traveling route (target route) along which the work vehicle <NUM> is caused to automatically travel within the field. The work vehicle <NUM> automatically travels along a predetermined target route within the field, based on position information on a current position of the work vehicle <NUM> to be computed by a positioning device <NUM>. The work vehicle <NUM> can also perform a predetermined work (e.g., a planting work), while automatically traveling within the field.

For example, the work vehicle <NUM> automatically travels along a target route R within a field F illustrated in <FIG>. The field F illustrated in <FIG> includes an inner area Fa, and a headland area Fb (outer peripheral area), and a ridge A1 (such as a bank) is formed on the outside of the field F in such a way as to surround the periphery of the field F. The target route R including a plurality of work routes is set in advance in the field F. For example, a work route Ra along which the work vehicle <NUM> reciprocally travels in parallel from a work start position S is set in the inner area Ra, and a work route Rb along which the work vehicle <NUM> travels spirally along an outer periphery toward a work end position G is set in the headland area Fb. The target route R is not limited to the route illustrated in <FIG>, but may be set as appropriate according to a shape of the field F, a work content, and the like.

The work vehicle <NUM> starts automatic traveling from the work start position S, and performs a work within the inner area Fa, while reciprocally traveling along the work route Ra. Also, the work vehicle <NUM> performs a work within the headland area Fb, while traveling around along the work route Rb until the work end position G.

Herein, in a case where the work vehicle <NUM> is caused to automatically travel within an outer peripheral area (headland area Fb) of the field F, for example, a distance between the ridge A1 located on an outer periphery of the field F, and the work vehicle <NUM> becomes close, and the work vehicle <NUM> may come into contact with the ridge. For example, in a case where the work vehicle <NUM> travels along the ridge A1 in an outermost peripheral area of the headland area Fb, a work machine <NUM> of the work vehicle <NUM> may come into contact with the ridge A1. For this reason, in the conventional art, the target route R on the outermost periphery is set to a position away from the ridge A1 by a predetermined distance. This does not allow the work vehicle <NUM> to automatically travel in the vicinity of the ridge A1, which causes a problem that work efficiency is lowered. In contrast, an automatic traveling system <NUM> according to the present embodiment can improve work efficiency of the work vehicle <NUM> in an outer peripheral area of the field F, as described below.

As illustrated in <FIG>, <FIG>, the work vehicle <NUM> includes a vehicle control device <NUM>, a storage unit <NUM>, a vehicle body unit <NUM>, the work machine <NUM>, a communication unit <NUM>, the positioning device <NUM>, an obstacle detection unit <NUM>, and the like. The vehicle control device <NUM> is electrically connected to the storage unit <NUM>, the vehicle body unit <NUM>, the work machine <NUM>, the positioning device <NUM>, the obstacle detection unit <NUM>, and the like. Note that, the vehicle control device <NUM> and the positioning device <NUM> may be wirelessly communicable.

First, a rice transplanter, which is an example of the work vehicle <NUM>, is described with reference to <FIG> is a side view of the work vehicle <NUM> (rice transplanter), and <FIG> is a plan view of the work vehicle <NUM>. The work vehicle <NUM> includes the vehicle body unit <NUM>, a pair of left and right front wheels <NUM>, a pair of left and right rear wheels <NUM>, the work machine <NUM> (planting unit), and the like.

An engine (drive unit) <NUM> is disposed inside a hood <NUM> disposed on a front portion of the vehicle body unit <NUM>. Power generated by the engine <NUM> is transmitted to the front wheels <NUM> and the rear wheels <NUM> via a transmission case <NUM>. Power transmitted via the transmission case <NUM> is also transmitted to the work machine <NUM> via a PTO shaft <NUM> disposed on a rear portion of the vehicle body unit <NUM>. Note that, the PTO shaft <NUM> is configured in such a way as to transmit power via a planting clutch (work clutch) (not illustrated). A driver's seat <NUM> on which an operator is seated is provided at a position between the front wheels <NUM> and the rear wheels <NUM> in a front-rear direction of the vehicle body unit <NUM>.

Operating tools such as a steering wheel <NUM>, a main shift lever (not illustrated), and a planting clutch lever (not illustrated) are disposed in front of the driver's seat <NUM>. The steering wheel <NUM> is an operating tool for changing a steering angle of the work vehicle <NUM>. The main shift lever is configured in such a way that at least "forward", "backward", and "seedling transfer" positions are selectable. When the main shift lever is operated to the "forward" position, power is transmitted in such a way that the front wheels <NUM> and the rear wheels <NUM> rotate in a direction in which the work vehicle <NUM> is moved forward. When the main shift lever is operated to the "backward" position, power is driven in such a way that the front wheels <NUM> and the rear wheels <NUM> rotate in a direction in which the work vehicle <NUM> is moved backward. When the main shift lever is operated to the "seedling transfer" position, transmission of power to the front wheels <NUM>, the rear wheels <NUM>, and the PTO shaft <NUM> is cut off. In addition, operating the planting clutch lever enables to switch between a transmission state in which the planting clutch transmits power to the PTO shaft <NUM> (i.e., the work machine <NUM>), and a cut-off state in which the planting clutch does not transmit power to the PTO shaft <NUM> (i.e., the work machine <NUM>).

The work machine <NUM> is connected to a rear portion of the vehicle body unit <NUM> via an elevating link mechanism <NUM>. The elevating link mechanism <NUM> is constituted of a parallel link structure including a top link <NUM>, a lower link <NUM>, and the like. A lifting cylinder (lifting device) <NUM> is connected to the lower link <NUM>. Extending and retracting the lifting cylinder <NUM> enables to raise and lower the entirety of the work machine <NUM>. This allows to change a height of the work machine <NUM> between a lowered position where the work machine <NUM> is lowered, and a planting work is performed, and a raised position where the work machine <NUM> is raised, and a planing work is not performed. Although the lifting cylinder <NUM> is a hydraulic cylinder, an electric cylinder may also be used. The work machine <NUM> may also be raised and lowered by an actuator other than a cylinder.

The work machine <NUM> (planting unit) includes a planting input case <NUM>, a plurality of planting units <NUM>, a seedling stand <NUM>, a plurality of floats <NUM>, and the like.

Each planting unit <NUM> includes a planting transmission case <NUM> and a rotation case <NUM>. Power is transmitted to the planting transmission case <NUM> via the PTO shaft <NUM> and the planting input case <NUM>. The rotation case <NUM> is mounted on both sides of each planting transmission case <NUM> in a vehicle width direction. Two planting claws <NUM> are mounted on each rotation case <NUM> side by side in a traveling direction of the work vehicle <NUM>. Planting one row of seedlings is performed by these two planting claws <NUM>.

As illustrated in <FIG>, the seedling stand <NUM> is disposed in front of and above the planting unit <NUM>, and is configured to be able to place a seedling mat. The seedling stand <NUM> is configured to be reciprocally movable for horizontal feeding (slidable in a horizontal direction). The seedling stand <NUM> is also configured to be able to intermittently transport a seedling mat downward for vertical feeding at a reciprocating moving end of the seedling stand <NUM>. This configuration allows the seedling stand <NUM> to supply seedlings on a seedling mat to each planting unit <NUM>. In this way, the work vehicle <NUM> can sequentially supply seedlings to each planting unit <NUM>, and continuously plant seedlings.

The float <NUM> illustrated in <FIG> is provided at a lower portion of the work machine <NUM>, and disposed in such a way that a lower surface of the float <NUM> can come into contact with the ground. Contact of the float <NUM> with the ground allows preparation of a surface of a rice field before planting seedlings. The float <NUM> is also provided with a float sensor (not illustrated) that detects a swing angle of the float <NUM>. The swing angle of the float <NUM> is associated with a distance between a surface of a rice field and the work machine <NUM>. The work vehicle <NUM> can keep a height of the work machine <NUM> with respect to the ground to a constant level by operating the lifting cylinder <NUM>, based on a swing angle of the float <NUM>, and raising and lowering the work machine <NUM>.

A spare seedling stand <NUM> is disposed outside the hood <NUM> in the vehicle width direction, and can carry a seedling box containing spare mat seedlings. Upper portions of a pair of left and right spare seedling stands <NUM> are connected to each other by a connecting frame <NUM> extending in an up-down direction and in the vehicle width direction. The positioning device <NUM> is disposed at a middle of the connecting frame <NUM> in the vehicle width direction. A positioning control unit <NUM>, a storage unit <NUM>, a communication unit <NUM>, and a positioning antenna <NUM> (see <FIG>) are disposed inside the positioning device <NUM>. The positioning antenna <NUM> can receive a radio wave from a positioning satellite constituting a satellite positioning system (GNSS). Performing known positioning computation, based on the radio wave enables to acquire a position of the work vehicle <NUM>.

An obstacle detection unit <NUM> is provided on both side surfaces of the vehicle body unit <NUM>. For example, as illustrated in <FIG>, an obstacle detection unit <NUM> capable of detecting an obstacle in a left direction of the work vehicle <NUM> is provided on the left side surface of the vehicle body unit <NUM>, and an obstacle detection unit 17R capable of detecting an obstacle in a right direction of the work vehicle <NUM> is provided on the right side surface of the vehicle body unit <NUM>. The obstacle detection unit <NUM> is constituted of a sensor that detects an obstacle in a predetermined detection area by using, for example, an infrared ray, an ultrasonic wave, and the like. For example, the obstacle detection unit <NUM> may be a LIDAR sensor (distance sensor) capable of measuring a distance to a measurement target (obstacle) in a three-dimensional manner by using a laser, or a sonar sensor including a plurality of sonars capable of measuring a distance to a measurement target by using an ultrasonic wave. <FIG> schematically illustrates a plan view of the work vehicle <NUM> in a case where the obstacle detection unit <NUM> is constituted of an optical sensor. The obstacle detection unit <NUM> is provided on the left side surface of the vehicle body unit <NUM> of the work vehicle <NUM>, and the obstacle detection unit 17R is provided on the right side surface of the vehicle body unit <NUM> of the work vehicle <NUM>.

Note that, a dotted line illustrated in <FIG> indicates a target area (determination area) for determination processing of determining whether an obstacle is an object to be avoided, in a case where the obstacle detection unit <NUM> detects the obstacle. Details will be described later, but, for example, in a case where the obstacle detection unit <NUM> detects an obstacle within the determination area, the vehicle control device <NUM> performs determination processing of determining whether the obstacle is an object to be avoided (e.g., a ridge A1). On the other hand, in a case where the obstacle detection unit <NUM> detects an obstacle within the detection area and outside the determination area, the vehicle control device <NUM> omits the determination processing. The determination area is set, for example, to a radius of <NUM> to <NUM> with respect to a mounting position of the obstacle detection unit <NUM> as a center. Note that, the detection area of the obstacle detection unit <NUM> is set to an area larger than the determination area.

The obstacle is, for example, the ridge A1, a water intake, a utility pole, materials temporarily placed within the field F, a person, and the like. The obstacle detection unit <NUM> is configured to be able to detect the obstacle within the detection area. When the obstacle detection unit <NUM> detects the obstacle, the obstacle detection unit <NUM> transmits a detection result (measurement information to be described later) to the vehicle control device <NUM>.

As another embodiment, the obstacle detection unit <NUM> may be constituted of a physical detection device (physical sensor). <FIG> schematically illustrates a plan view of the work vehicle <NUM> in a case where the obstacle detection unit <NUM> is constituted of a contact sensor (or a switch). The obstacle detection unit <NUM> detects an obstacle, in a case where the obstacle comes into contact with the obstacle detection unit <NUM>. In the first embodiment, a case in which the obstacle detection unit <NUM> is an optical sensor (see <FIG>) is described as an example. A configuration in a case where the obstacle detection unit <NUM> is a physical sensor (see <FIG>) is described later in the [Second Embodiment].

The storage unit <NUM> is a non-volatile storage unit such as a hard disk drive (HDD) or a solid state drive (SSD) that stores various pieces of information. The storage unit <NUM> stores a control program such as an automatic traveling program for causing the vehicle control device <NUM> to perform automatic traveling processing. For example, the automatic traveling program is non-transitorily recorded in a computer-readable recording medium such as a flash ROM, an EEPROM, a CD, or a DVD, read by a predetermined reading device (not illustrated), and stored in the storage unit <NUM>. Note 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>. Also, the storage unit <NUM> may store route data on the target route R to be generated in the operation terminal <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 pieces of arithmetic processing. The ROM is a non-volatile storage unit that stores in advance a control program such as a BIOS and an OS for causing the CPU to execute various pieces of arithmetic processing. The RAM is a volatile or non-volatile storage unit that stores various pieces of information, and is used as a temporary storage memory (work area) in which the CPU executes various pieces of processing. Further, the vehicle control device <NUM> controls the work vehicle <NUM> by causing the CPU to execute various control programs stored in advance in the ROM or the storage unit <NUM>.

The vehicle control device <NUM> controls an operation of the work vehicle <NUM> in response to various operations by the user with respect to the work vehicle <NUM>. The vehicle control device <NUM> also performs automatic traveling processing of the work vehicle <NUM>, based on a current position of the work vehicle <NUM> to be computed by the positioning device <NUM>, and the target route R set in advance.

As illustrated in <FIG>, the vehicle control device <NUM> includes various processing units such as a traveling processing unit <NUM>, a detection processing unit <NUM>, and a determination processing unit <NUM>. Note that, the vehicle control device <NUM> functions as the various processing units by causing the CPU to execute various pieces of processing according to the automatic traveling program. Also, a part or all of the processing units may be constituted of an electronic circuit. Note that, the automatic traveling program may be a program for causing a plurality of processors to function as the processing units.

The traveling processing unit <NUM> controls traveling of the work vehicle <NUM>. Specifically, the traveling processing unit <NUM> causes the work vehicle <NUM> to automatically travel along the target route R set within the field F. For example, when the traveling processing unit <NUM> acquires a traveling start instruction from the operation terminal <NUM>, the traveling processing unit <NUM> starts automatic traveling of the work vehicle <NUM>. For example, in a case where a current position of the work vehicle <NUM> is a position that satisfies a traveling start condition, when an operator presses a start button on an operation screen of the operation terminal <NUM>, the operation terminal <NUM> outputs a traveling start instruction to the work vehicle <NUM>. When the traveling processing unit <NUM> acquires the traveling start instruction from the operation terminal <NUM>, the traveling processing unit <NUM> causes the work vehicle <NUM> to start automatic traveling along the target route R.

Further, when the traveling processing unit <NUM> acquires a traveling stop instruction from the operation terminal <NUM>, the traveling processing unit <NUM> stops automatic traveling of the work vehicle <NUM>. For example, when the operator presses a temporary stop button on an operation screen of the operation terminal <NUM>, the operation terminal <NUM> outputs a traveling stop instruction to the work vehicle <NUM>.

The traveling processing unit <NUM> also controls traveling of the work vehicle <NUM>, based on a detection result by the obstacle detection unit <NUM>. Traveling control based on the detection result is described later.

The detection processing unit <NUM> acquires a detection result (measurement information) from the obstacle detection unit <NUM>. Also, the detection processing unit <NUM> detects an obstacle located on an outer periphery of the field F, while the work vehicle <NUM> is traveling along the target route R in an outer periphery area (headland area Fb) of the field F. Specifically, the detection processing unit <NUM> acquires measurement information on each detection area from the obstacle detection units <NUM> and 17R. For example, in a case where an obstacle enters the detection area, the detection processing unit <NUM> acquires a measurement distance (distance from the obstacle detection unit <NUM> to the obstacle) to be measured by the obstacle detection unit <NUM>. The detection processing unit <NUM> also determines a position and a shape of the obstacle, based on the measurement information. The detection processing unit <NUM> may be included in a device (detection device) different from the vehicle control device <NUM>. The detection device may also be configured to include the obstacle detection unit <NUM> and the detection processing unit <NUM>.

The determination processing unit <NUM> determines an obstacle detected by the obstacle detection unit <NUM>. Specifically, the determination processing unit <NUM> performs determination processing of determining whether an obstacle detected within the determination area is an object to be avoided. For example, the determination area is set within a range of a radius of <NUM> from a mounting position of the obstacle detection unit <NUM>. In this case, the determination processing unit <NUM> performs the determination processing, based on the measurement distance to be acquired from the detection processing unit <NUM>, in a case where the obstacle detection unit <NUM> detects an obstacle within the determination area.

For example, the determination processing unit <NUM> detects an edge of an obstacle, based on a position and a shape of the obstacle detected from the measurement information by the detection processing unit <NUM>, and determines whether the obstacle is the ridge A1, based on whether a boundary of the obstacle is continuous. The determination processing unit <NUM> determines that the obstacle is the ridge A1, in a case where the boundary of the obstacle is continuous, and the detected position is determined as a point group. On the other hand, in a case where the boundary of the obstacle is not continuous, and the detected position is determined as a point, the determination processing unit <NUM> determines that the obstacle is an object (such as a person) other than the ridge A1.

The traveling processing unit <NUM> controls automatic traveling of the work vehicle <NUM>, based on a determination result of the determination processing unit <NUM>. Specifically, in a case where the determination processing unit <NUM> determines that the obstacle is the ridge A1, the traveling processing unit <NUM> causes the work vehicle <NUM> to perform avoidance traveling of avoiding the ridge A1. A specific example of the avoidance traveling is described with reference to <FIG>.

<FIG> illustrates a state in which the work vehicle <NUM> is automatically traveling along the work route Rb on the outermost periphery of the headland area Fb. In the state illustrated in <FIG>, since a distance between the work vehicle <NUM> and the ridge A1 on the left side is equal to or more than <NUM>, and the ridge A1 is outside the determination area, the determination processing unit <NUM> does not perform the determination processing, assuming that there is no risk that the work vehicle <NUM> comes into contact with the ridge A1.

Subsequently, when the work vehicle <NUM> moves straight ahead along the work route Rb, the obstacle detection unit <NUM> detects an obstacle at a position illustrated in <FIG>. The obstacle is a part of the ridge A1 partially protruding into the field F. The detection processing unit <NUM> determines a position and a shape of the obstacle, based on measurement information of the obstacle detection unit <NUM>. Since the protruding portion of the obstacle is included in the determination area, the determination processing unit <NUM> determines whether the obstacle is the ridge A1, based on the position and the shape of the obstacle. Herein, since a boundary of the obstacle has continuity, and is determined as a point group, the determination processing unit <NUM> determines that the obstacle is the ridge A1.

When the determination processing unit <NUM> determines that the obstacle is the ridge A1, the traveling processing unit <NUM> sets an avoidance route r1 to a position where the work route Rb (target route R) is offset to the inside of the field F. For example, the traveling processing unit <NUM> sets the avoidance route r1 to a position where the target route R is offset by a distance (offset amount L1) according to a protruding width of a protruding portion of the ridge A1. Note that, the offset amount L1 may be set according to the protrusion width, or may be set to a predetermined distance in advance. The traveling processing unit <NUM> causes the work vehicle <NUM> to travel along the avoidance route r1 inside the field F than the target route R.

For example, when the traveling processing unit <NUM> sets the avoidance route r1, the traveling processing unit <NUM> changes the traveling direction of the work vehicle <NUM> to the direction of the avoidance route r1 (see <FIG>). This allows the work vehicle <NUM> to move from the position where the ridge A1 is detected to the avoidance route r1, and to automatically travel along the avoidance route r1 (see <FIG>).

Subsequently, in a case where the work vehicle <NUM> has traveled along the avoidance route r1, and passed the ridge A1, the traveling processing unit <NUM> causes the work vehicle <NUM> to return to the target route R (work route Rb). For example, as illustrated in <FIG>, when the work vehicle <NUM> has traveled straight ahead along the avoidance route r1, and the determination area no longer includes the ridge A1 (protruding portion), the traveling processing unit <NUM> changes the traveling direction of the work vehicle <NUM> to the direction of the work route Rb (see <FIG>). This allows the work vehicle <NUM> to return to the original work route Rb from the avoidance route r1, and to automatically travel along the work route Rb.

According to the configuration described above, the work vehicle <NUM> can automatically travel on the outermost periphery of the field F along the ridge A1. Also, in a case where the work vehicle <NUM> detects the ridge A1, while automatically traveling on the outermost periphery, the work vehicle <NUM> can maintain automatic traveling by traveling along the avoidance route r1 in such a way as not to come into contact with the ridge A1. Also, by setting the determination area (see <FIG>) for determining whether the obstacle is an object to be avoided, it becomes possible to cause the work vehicle <NUM> to automatically travel along the ridge A1 on the outermost periphery of the field F, while maintaining a distance between the object to be avoided and the work vehicle <NUM> to a constant value.

Note that, in a case where the determination processing unit <NUM> determines that the obstacle is not the ridge A1, the traveling processing unit <NUM> stops automatic traveling of the work vehicle <NUM>. In this case, the traveling processing unit <NUM> resumes automatic traveling of the work vehicle <NUM>, in a case where the obstacle has moved, or in a case where an instruction operation by the operator is accepted.

In a case where the position of the obstacle detected by the detection processing unit <NUM> is outside the determination area, the traveling processing unit <NUM> maintains automatic traveling of the work vehicle <NUM> along the target route R.

In this way, the vehicle control device <NUM> performs processing of detecting an obstacle located on an outer periphery of the field F, while the work vehicle <NUM> is traveling along the target route R in an outer peripheral area of the field F, and in a case where the obstacle is an object to be avoided (e.g., the ridge A1), the vehicle control device <NUM> performs processing of causing the work vehicle <NUM> to travel along the avoidance route r1 inside the field F than the target route R.

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

The communication unit <NUM> is a communication interface that connects the operation terminal <NUM> to the communication network N1 wiredly or wirelessly, and performs data communication with an external device such as one or more work vehicles <NUM> via the communication network N1 in accordance with a predetermined communication protocol.

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 pieces of information, and an operation unit such as a touch panel that accepts an operation, a mouse, or a keyboard. An operator can perform, on an operation screen to be displayed on the display unit, an operation of registering various pieces of information (such as work vehicle information, field information, and work information to be described later) by operating the operation unit. For example, the operator performs, on the operation unit, an operation of registering the field F as a work target.

The operator can also perform a traveling start instruction, a traveling stop instruction, and the like with respect to the work vehicle <NUM> by operating the operation unit. Furthermore, the operator can recognize, at a position away from the work vehicle <NUM>, a traveling state of the work vehicle <NUM> that automatically travels within the field F along the target route R by a traveling trajectory to be displayed on the operation terminal <NUM>.

The storage unit <NUM> is a non-volatile storage unit such as an HDD or an SSD that stores various pieces of information. The storage unit <NUM> stores a control program for causing the operation control unit <NUM> to perform predetermined processing. For example, the control program is non-transitorily recorded in a computer-readable recording medium such as a flash ROM, an EEPROM, a CD, or a DVD, read by a predetermined reading device (not illustrated), and stored in the storage unit <NUM>. Note that, the control 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>.

In addition, a dedicated application for causing the work vehicle <NUM> to automatically travel is installed in the storage unit <NUM>. The operation control unit <NUM> activates the dedicated application, and performs setting processing on various pieces of information related to the work vehicle <NUM>, generation processing of the target route R of the work vehicle <NUM>, an automatic traveling instruction with respect to the work vehicle <NUM>, and the like.

In addition, the storage unit <NUM> stores data such as work vehicle information being information related to the work vehicle <NUM>, and target route information being information related to the target route R. The work vehicle information includes information such as a vehicle number and a model number for each work vehicle <NUM>. The vehicle number is identification information of the work vehicle <NUM>. The model number is a model number of the work vehicle <NUM>.

Note that, the storage unit <NUM> may store the work vehicle information related to one work vehicle <NUM>, or may store the work vehicle information related to a plurality of work vehicles <NUM>. For example, in a case where a specific operator owns a plurality of work vehicles <NUM>, the work vehicle information related to each work vehicle <NUM> is stored in the storage unit <NUM>.

The target route information includes information such as a route name, a field name, an address, a field area, and a work time for each target route R. The route name is a route name of the target route R generated in the operation terminal <NUM>. The field name is a name of the field F as a work target, for which the target route R is set. The address is an address of the field F. The field area is an area of the field F. The work time is a time required for a work in the field F by the work vehicle <NUM>.

Note that, the storage unit <NUM> may store the target route information related to one target route R, or may store the target route information related to a plurality of target routes R. For example, in a case where a specific operator generates a plurality of target routes R with respect to one or more fields F owned by himself/herself, the storage unit <NUM> stores the target route information related to each target route R. Note that, one target route R may be set for one field F, or a plurality of target routes R may be set for one field F.

The storage unit <NUM> may store position information on the ridge A1 that is detected while the work vehicle <NUM> is traveling along the target route R. For example, as illustrated in <FIG>, in a case where the work vehicle <NUM> travels along the avoidance route R1, the work vehicle <NUM> travels at a position (in an already worked area) of an already planted crop, which may adversely affect the crop. In this case, for example, in a work next year and thereafter, it becomes possible to work using position information on the ridge A1 stored in the storage unit <NUM>. Specifically, in the field F illustrated in <FIG>, the work vehicle <NUM> is expected to travel along the avoidance route r1 in a process of one step before a work in a process for an outer periphery (outermost periphery). Therefore, the work vehicle <NUM> performs a row stop operation on a side of the already worked area, and is prevented from planting a crop. In the example illustrated in <FIG>, the work vehicle <NUM> performs a row stop operation for two rows on the right side that are included in the already worked area. This configuration enables to prevent an adverse effect on a crop when the work vehicle <NUM> travels along the avoidance route r1.

Note that, as another embodiment, a part or all of pieces of information such as the work vehicle information and the target route information may be stored in a server accessible from the operation terminal <NUM>. The operator may perform an operation of registering the work vehicle information and the target route information in the server (e.g., a personal computer, a cloud server, or the like).

The operation control unit <NUM> includes a control device such as a CPU, a ROM, and a RAM. The CPU is a processor that executes various pieces of arithmetic processing. The ROM is a non-volatile storage unit that stores in advance a control program such as a BIOS and an OS for causing the CPU to execute various pieces of arithmetic processing. The RAM is a volatile or non-volatile storage unit that stores various pieces of information, and is used as a temporary storage memory for various pieces of processing to be executed by the CPU. Further, the operation control unit <NUM> controls the operation terminal <NUM> by causing the CPU to execute various control programs stored in advance in the ROM or the storage unit <NUM>.

As illustrated in <FIG>, the operation control unit <NUM> includes various processing units such as a setting processing unit <NUM>, and an output processing unit <NUM>. Note that, the operation control unit <NUM> functions as the various processing units by causing the CPU to execute various pieces of processing in accordance with the control program. Also, a part or all of the processing units may be constituted of an electronic circuit. Note that, the control program may be a program for causing a plurality of processors to function as the processing units.

The setting processing unit <NUM> sets information related to the work vehicle <NUM> (hereinafter, referred to as "work vehicle information"), information related to the field F (hereinafter, referred to as "field information"), and information as to how a work is specifically performed (hereinafter, referred to as "work information"). The setting processing unit <NUM> accepts a setting operation by the operator on a setting screen D1 illustrated in <FIG>, for example, and registers each piece of setting information.

Specifically, regarding information such as a model number of the work vehicle <NUM>, a position where the positioning antenna <NUM> is mounted on the work vehicle <NUM>, a type of the work machine <NUM>, a size and a shape of the work machine <NUM>, a position of the work machine <NUM> with respect to the work vehicle <NUM>, a traveling speed and an engine speed of the work vehicle <NUM> during a work, and a traveling speed and an engine speed of the work vehicle <NUM> during turning, the setting processing unit <NUM> sets the information by performing a registration operation on the operation terminal <NUM> by the operator.

Regarding information such a position and a shape of the field F, the work start position S at which a work is started, the work end position G at which a work is finished, and a work direction, the setting processing unit <NUM> also sets the information by performing a registration operation on the operation terminal <NUM>.

Information on a position and a shape of the field F can be automatically acquired, for example, by allowing the operator to board the work vehicle <NUM> and drive the work vehicle <NUM> in such a way as to travel around along an outer periphery of the field F, and recording a transition of position information of the positioning antenna <NUM> at this occasion. Further, a position and a shape of the field F can also be acquired by allowing the operator to operate the operation terminal <NUM> in a state that a map is displayed on the operation terminal <NUM>, and based on a polygonal shape acquired by determining a plurality of points on the map. An area to be determined by the acquired position and shape of the field F is an area (traveling area) where the work vehicle <NUM> is allowed to travel.

The setting processing unit <NUM> is also configured in such a way that presence or absence of a cooperative work by a work vehicle <NUM> (unmanned tractor) and a manned work vehicle <NUM>, the number of skips, which is the number of work routes to be skipped in a case where the work vehicle <NUM> turns around in a headland, a width of a headland, a width of a non-cultivated field, and the like are settable as work information.

For example, the setting processing unit <NUM> sets a work area within the registered field F where a work is actually performed. For example, when the operator selects "work area registration" on the setting screen D1 (see <FIG>), and selects the field F for which a work area is registered, the setting processing unit <NUM> displays a registration screen (map screen) on which the work start position S and the work end position G are registered. The operator registers the work start position S and the work end position G at any position within the field F on the registration screen.

The setting processing unit <NUM> also generates the target route R along which the work vehicle <NUM> is caused to automatically travel within the field F, based on each piece of the setting information. For example, when the operator selects "route generation" on the setting screen D1 (see <FIG>), the setting processing unit <NUM> causes to display a registration screen (not illustrated) for generating a route. After the operator registers, on the registration screen, each piece of information such as the field F, the work machine <NUM>, a turning method, a headland, a vehicle speed, and an engine speed, the operator performs a route generation instruction. Upon acquiring the route generation instruction, the setting processing unit <NUM> generates the target route R, based on the work start position S, the work end position G, and each piece of the information.

For example, as illustrated in <FIG>, the setting processing unit <NUM> generates the target route R including the work start position S, the work end position G, and the work routes Ra and Rb. The setting processing unit <NUM> registers the generated target route R in association with the field F.

The output processing unit <NUM> outputs route data on the target route R to the work vehicle <NUM>. For example, when the operator selects the field F as a work target, and a work route (target route R), and performs a work start operation, the output processing unit <NUM> outputs route data on the target route R associated with the field F to the work vehicle <NUM>.

When the work vehicle <NUM> receives the route data on the target route R generated in the operation terminal <NUM>, the work vehicle <NUM> stores the data in the storage unit <NUM>. In addition, in a case where the travel start condition is satisfied, the work vehicle <NUM> starts automatic traveling in response to a traveling start instruction by the operator. While the work vehicle <NUM> is automatically traveling, the operator can recognize a traveling state within the field F on the operation terminal <NUM>.

Note that, the operation terminal <NUM> may be accessible to a website (agricultural support site) of agricultural support services provided by a server (not illustrated) via the communication network N1. In this case, the operation terminal <NUM> is able to function as an operation terminal for the server by causing the operation control unit <NUM> to execute a browser program. Further, the server includes each processing unit described above, and performs each piece of processing.

In the following, an example of the automatic traveling processing to be performed by the automatic traveling system <NUM> is described with reference to <FIG>.

Note that, the present invention can be described as an invention directed to an automatic traveling method in which one or more steps included in the automatic traveling processing are performed. Further, one or more steps included in the automatic traveling processing described herein may be omitted as appropriate. Note that, the order of execution of each step in the automatic traveling processing may be different, as far as similar advantageous effects are generated. Furthermore, although a case is described herein as an example, in which the vehicle control device <NUM> performs each step in the automatic traveling processing, an automatic traveling method in which one or more processors perform each step in the automatic traveling processing in a distributed manner is also considered as another embodiment.

First, in step S11, the vehicle control device <NUM> of the work vehicle <NUM> determines whether the traveling start instruction has been acquired from the operation terminal <NUM>. When the vehicle control device <NUM> acquires the traveling start instruction (S <NUM>: Yes), the vehicle control device <NUM> proceeds the processing to step S12. The vehicle control device <NUM> waits until the traveling start instruction is acquired (S11: No).

In step S12, the vehicle control device <NUM> causes the work vehicle <NUM> to start automatic traveling. The vehicle control device <NUM> causes the work vehicle <NUM> to start automatic traveling along the target routes R (work routes Ra and Rb) from the work start position S. For example, the work vehicle <NUM> automatically travels along the work routes Ra and Rb in a state that the work machine <NUM> (planting unit) is lowered.

Next, in step S13, the vehicle control device <NUM> determines whether an obstacle is detected. Specifically, the vehicle control device <NUM> acquires measurement information from the obstacle detection unit <NUM>, and determines whether an obstacle is included in the determination area (see <FIG>), based on the measurement information. In a case where the obstacle is detected (S13: Yes), the vehicle control device <NUM> proceeds the processing to step S14. On the other hand, in a case where the obstacle is not detected (S13: No), the vehicle control device <NUM> proceeds the processing to step S18. Note that, in a case where the obstacle detection unit <NUM> does not detect an obstacle, and in a case where the obstacle detection unit <NUM> detects an obstacle outside the determination area, the vehicle control device <NUM> proceeds the processing to step S18.

As another embodiment, the vehicle control device <NUM> may proceed the processing to step S14, in a case where an obstacle is detected a predetermined number of times or more within a predetermined time in the determination area.

In step S14, the vehicle control device <NUM> performs determination processing of determining whether a detected obstacle is the ridge A1. For example, the vehicle control device <NUM> detects an edge of an obstacle, based on a position and a shape of the obstacle detected from the measurement information, and determines whether the obstacle is the ridge A1, based on whether a boundary of the obstacle is continuous. In a case where the vehicle control device <NUM> determines that the obstacle is the ridge A1 (S14: Yes), the vehicle control device <NUM> proceeds the processing to step S15. For example, as illustrated in <FIG>, when the vehicle control device <NUM> detects a protruding portion of the ridge A1, while the work vehicle <NUM> is automatically traveling on the outermost periphery of the field F along the ridge A1, the vehicle control device <NUM> determines that the obstacle is the ridge A1.

On the other hand, in a case where the vehicle control device <NUM> determines that the obstacle is not the ridge A1 (S14: No), the vehicle control device <NUM> proceeds the processing to step S <NUM>. Upon proceeding to step S <NUM>, the vehicle control device <NUM> stops the work vehicle <NUM>, and thereafter, in a case where the obstacle has moved, or in a case where an instruction operation by the operator is accepted, the vehicle control device <NUM> returns the processing to step S13, and causes the work vehicle <NUM> to resume automatic traveling.

In step S15, the vehicle control device <NUM> offsets the target route R. For example, as illustrated in <FIG>, the vehicle control device <NUM> sets the avoidance route r1 to a position offset by a distance (offset amount L1) according to a protruding width of a protruding portion of the ridge A1. After setting the avoidance route r1, the vehicle control device <NUM> causes the work vehicle <NUM> to automatically travel along the avoidance route r1 (see <FIG>). The vehicle control device <NUM> may also set a traveling speed of the work vehicle <NUM> in the avoidance route r1 to a slower speed (e.g., <NUM>/s) than the traveling speed (e.g., <NUM>/s) of the work vehicle <NUM> in the target route R. This can ensure safety of automatic traveling in the avoidance route r1.

Next, in step S16, the vehicle control device <NUM> determines whether it is possible to return the work vehicle <NUM> to the target route R (work route Rb). For example, in a case where the work vehicle <NUM> travels straight ahead along the avoidance route r1, and no obstacle (ridge A1) is detected within the determination area (see <FIG>), the vehicle control device <NUM> determines that it is possible to return the work vehicle <NUM> to the target route R. When the vehicle control device <NUM> determines that it is possible to return the work vehicle <NUM> to the target route R (S16: Yes), the vehicle control device <NUM> proceeds the processing to step S17. On the other hand, when the vehicle control device <NUM> determines that the ridge A1 is included in the determination area, and it is not possible to return the work vehicle <NUM> to the target route R, automatic traveling along the avoidance route r1 (see <FIG>) is continued (S16: No).

In step S17, the vehicle control device <NUM> returns the work vehicle <NUM> from the avoidance route r1 to the original target route R (work route Rb), and causes the work vehicle <NUM> to resume automatic traveling along the target route R.

Next, in step S18, the vehicle control device <NUM> determines whether the work vehicle <NUM> has reached the work end position G. For example, the vehicle control device <NUM> terminates the processing, when the work vehicle <NUM> reaches the work end position G (S18: Yes). The vehicle control device <NUM> continues the above-described pieces of processing (S13 to S17) until the work vehicle <NUM> reaches the work end position G (S18: No). The vehicle control device <NUM> performs the automatic traveling processing as described above.

As described above, the automatic traveling system <NUM> and the automatic traveling method according to the present embodiment performs: causing the work vehicle <NUM> to automatically travel along the target route R set within the field F; detecting an obstacle located on an outer periphery of the field F, while the work vehicle <NUM> is traveling along the target route R in an outer peripheral area (headland area Fb) of the field F; and causing the work vehicle <NUM> to travel along the avoidance route r1 inside the field F than the target route R, in a case where the obstacle is an object to be avoided (e.g., the ridge A1).

According to the above configuration, it is possible to cause the work vehicle <NUM> to automatically travel along the ridge A1 located, for example, on an outer periphery of the field F, within an outermost peripheral area of the field F. Also, even in a case where the work vehicle <NUM> approaches the ridge A1, it is possible to cause the work vehicle <NUM> to automatically travel along the avoidance route r1 away from the ridge A1. Therefore, it is possible to continue automatic traveling without stopping the work vehicle <NUM>. Since it becomes possible to cause the work vehicle <NUM> to automatically travel in the entirety of the field F, work efficiency of the work vehicle <NUM> can be improved.

Herein, the work vehicle <NUM> may be configured to be selectable between a traveling mode (unmanned traveling mode) in which the work vehicle <NUM> automatically travels without an operator on board, and a traveling mode (manned traveling mode) in which the work vehicle <NUM> automatically travels with an operator on board. In this case, the operator selects either "robot tractor" associated with the unmanned traveling mode, or "automatic tractor" associated with the manned traveling mode on an operation screen D2 (see <FIG>) of the operation terminal <NUM>.

The vehicle control device <NUM> may perform processing of detecting the obstacle, based on the traveling mode. Specifically, in a case where the traveling mode is set to the manned traveling mode, the vehicle control device <NUM> performs processing of determining whether the obstacle is an object to be avoided, in a case where a distance between the work vehicle <NUM> and the obstacle becomes equal to or less than a first set distance. For example, in a case where a distance to an obstacle detected by the detection processing unit <NUM> is <NUM> or less, the determination processing unit <NUM> determines whether the obstacle is the ridge A1. Then, in a case where the obstacle is the ridge A1, the traveling processing unit <NUM> causes the work vehicle <NUM> to travel while avoiding the obstacle. On the other hand, in a case where the distance to the obstacle detected by the detection processing unit <NUM> exceeds <NUM>, the determination processing unit <NUM> does not perform processing of determining whether the obstacle is the ridge A1. In this case, the traveling processing unit <NUM> maintains automatic traveling of the work vehicle <NUM> along the target route R.

In contrast, in a case where the traveling mode is set to the unmanned traveling mode, the vehicle control device <NUM> determines whether an obstacle is an object to be avoided, in a case where the distance between the work vehicle <NUM> and the obstacle becomes equal to or less than a second set distance. For example, in a case where the distance to the obstacle detected by the detection processing unit <NUM> is <NUM> or less, the determination processing unit <NUM> determines whether the obstacle is the ridge A1. Then, in a case where the obstacle is the ridge A1, the traveling processing unit <NUM> causes the work vehicle <NUM> to travel while avoiding the obstacle. On the other hand, in a case where the distance to the obstacle detected by the detection processing unit <NUM> exceeds <NUM>, the determination processing unit <NUM> does not perform processing of determining whether the obstacle is the ridge A1. In this case, the traveling processing unit <NUM> maintains automatic traveling of the work vehicle <NUM> along the target route R.

In this way, in a case where the operator boards the work vehicle <NUM>, the vehicle control device <NUM> performs determination (determination processing) as to whether an obstacle is an object to be avoided, in a case where a distance between the work vehicle <NUM> and the object to be avoided becomes equal to or less than the first set distance; and in a case where the operator does not board the work vehicle <NUM>, the vehicle control device <NUM> performs the determination processing, in a case where the distance between the work vehicle <NUM> and the object to be avoided becomes equal to or less than the second set distance, which is greater than the first set distance. Also, in a case where the operator boards (in a case of the manned traveling mode), the operator can visually check the distance to the object to be avoided (ridge A1). Therefore, a determination threshold value for avoidance traveling can be set to a value smaller than that in a case where the operator does not board (in a case of the unmanned traveling mode).

As another embodiment, the vehicle control device <NUM> may perform processing of determining whether an obstacle is the ridge A1, in a case where the obstacle is detected a predetermined number of times or more within a predetermined time in the determination area. The vehicle control device <NUM> may also set the predetermined time and the predetermined number of times according to the traveling mode. For example, the predetermined time in a case where the operator boards (in a case of the manned travel mode) may be set to a time longer than the predetermined time in a case where the operator does not board (in a case of the unmanned travel mode), and the predetermined number of times in a case where the operator boards (in a case of the manned travel mode) may be set to the number of times larger than the predetermined number of times in a case where the operator does not board (in a case of the unmanned travel mode). In this way, as with a case of the determination threshold value for avoidance traveling, in a case where the operator boards (in a case of the manned traveling mode), the operator can visually check the distance to the object to be avoided (ridge A1). Therefore, threshold values of the predetermined time and the predetermined number of times can be set to values larger than those in a case where the operator does not board (in a case of the unmanned traveling mode).

An automatic traveling system <NUM> according to the second embodiment of the present invention is described. In the automatic traveling system <NUM> according to the second embodiment, an obstacle detection unit <NUM> is constituted of a physical sensor, and other configuration is the same as that of the automatic traveling system <NUM> according to the first embodiment. In the following, differences from the automatic traveling system <NUM> according to the first embodiment are mainly described.

As illustrated in <FIG>, obstacle detection units <NUM> and 17R, each of which is constituted of a physical sensor (such as a contact sensor or a switch), are provided on a left side surface and a right side surface of a vehicle body unit <NUM> of a work vehicle <NUM>, respectively. The obstacle detection units <NUM> and 17R transmit a detection result (detection signal) to a vehicle control device <NUM>, in a case where the obstacle detection units <NUM> and 17R detect a contact with an obstacle.

A detection processing unit <NUM> acquires a detection result from the obstacle detection units <NUM> and 17R. For example, as illustrated in <FIG>, in a case where a protruding portion of a ridge A1 comes into contact with the obstacle detection unit <NUM>, while the work vehicle <NUM> is automatically traveling along a work route Rb on the outermost periphery of a headland area Fb, the obstacle detection unit <NUM> transmits a detection signal to the vehicle control device <NUM>, and the detection processing unit <NUM> acquires the detection signal.

When the detection processing unit <NUM> acquires the detection signal, a determination processing unit <NUM> determines that the obstacle is the ridge A1. For example, the determination processing unit <NUM> determines that the obstacle is the ridge A1 (object to be avoided), in a case where the detection processing unit <NUM> acquires the detection signal a predetermined number of times.

The predetermined number of times may be set according to the traveling mode (the manned traveling mode or the unmanned traveling mode). For example, in a case where the traveling mode is the manned traveling mode, the determination processing unit <NUM> determines that the obstacle is the ridge A1, in a case where the detection processing unit <NUM> successively acquires the detection signal three times. On the other hand, in a case where the traveling mode is the unmanned traveling mode, the determination processing unit <NUM> determines that the obstacle is the ridge A1, in a case where the detection processing unit <NUM> acquires the detection signal once. As another method of determining the ridge A1, the determination processing unit <NUM> may determine whether the obstacle is the ridge A1, based on an interval at which the detection signal is acquired. For example, the determination processing unit <NUM> acquires the detection signal with respect to a predetermined traveling distance of the work vehicle <NUM> to be computed by a rotation sensor (not illustrated) of a traveling wheel, and determines that the obstacle is the ridge A1, in a case where an interval between the successive detection signals is shorter than a threshold value.

When the determination processing unit <NUM> determines that the obstacle is the ridge A1, a traveling processing unit <NUM> sets an avoidance route r1, and changes the traveling direction of the work vehicle <NUM> to the direction of the avoidance route r1 (see <FIG>). This allows the work vehicle <NUM> to move from a position where the ridge A1 is detected to the avoidance route r1, and to automatically travel along the avoidance route r1 (see <FIG>).

After causing the work vehicle <NUM> to travel along the avoidance route r1 for a predetermined time or by a predetermined distance, the traveling processing unit <NUM> returns the work vehicle <NUM> to a target route R (work route Rb). The predetermined time and the predetermined distance are set in advance. For example, the predetermined time and the predetermined distance are set in advance based on information such as a shape of a field F and a shape of the ridge A1 to be measured when registering the field F.

As another embodiment, the predetermined time or the predetermined distance may be set to a first threshold value in a case of the manned traveling mode, and the predetermined time or the predetermined distance may be set to a second threshold value being greater than the first threshold value in a case of the unmanned traveling mode. In this way, since the operator can visually check the distance to an object to be avoided (ridge A1) in a case of the manned traveling mode, a threshold value of the predetermined time or the predetermined distance may be set to a value smaller than that in a case of the unmanned traveling mode.

Further as another embodiment, in a case of the manned traveling mode, the obstacle detection unit <NUM> may determine that an obstacle is an object to be avoided, in a case where the work vehicle <NUM> comes into contact with the obstacle a first predetermined number of times; and in a case of the unmanned traveling mode, the obstacle detection unit <NUM> may determine that an obstacle is an object to be avoided, in a case where the work vehicle <NUM> comes into contact with the obstacle a second predetermined number of times, which is less than the first predetermined number of times. In this way, since the operator can visually check the distance to an object to be avoided (ridge A1), in a case where the operator boards (in a case of the manned traveling mode), a threshold value of the predetermined number of times can be set to a value larger than that in a case where the operator does not board (in a case of the unmanned traveling mode).

<FIG> is a flowchart illustrating an example of the automatic traveling processing to be performed in the automatic traveling system <NUM> according to the second embodiment. Herein, differences from the automatic traveling processing to be performed in the automatic traveling system <NUM> according to the first embodiment illustrated in <FIG> are described.

When the vehicle control device <NUM> acquires the traveling start instruction from an operation terminal <NUM> (S21: Yes), and automatic traveling is started (S22), the vehicle control device <NUM> determines whether an obstacle is detected in step S23. For example, when the vehicle control device <NUM> acquires a detection signal from the obstacle detection unit <NUM>, in a case where an obstacle comes into contact with the obstacle detection unit <NUM>, the vehicle control device <NUM> determines that an obstacle has been detected (S23: Yes).

When an obstacle is detected (S23: Yes), the vehicle control device <NUM> determines whether the obstacle is the ridge A1. For example, the vehicle control device <NUM> determines that the obstacle is the ridge A1, in a case where the detection signal is successively acquired a predetermined number of times within a predetermined time (S24: Yes). Also, for example, the vehicle control device <NUM> may determine that the obstacle is not the ridge A1 (such as a person), in a case where the detection signal is acquired only once within a predetermined time (S24: No).

In step S25, the vehicle control device <NUM> offsets the target route R. For example, as illustrated in <FIG>, the vehicle control device <NUM> sets the avoidance route r1 to a position offset by a preset distance (offset amount L2). The offset amount L2 may be set in advance based on information such as a shape of the field F and a shape of the ridge A1 to be measured when registering the field F. When the vehicle control device <NUM> sets the avoidance route r1, the work vehicle <NUM> is caused to automatically travel along the avoidance route r1 (see <FIG>).

Note that, the vehicle control device <NUM> may offset the work vehicle <NUM>, while the obstacle detection unit <NUM> repeatedly comes into contact with a protruding portion of the ridge A1, and may set the avoidance route r1 to a position where the obstacle detection unit <NUM> no longer comes into contact with the protruding portion.

Next, in step S26, the vehicle control device <NUM> determines whether the work vehicle <NUM> has traveled along the avoidance route r1 by a predetermined distance. In a case where the work vehicle <NUM> has traveled along the avoidance route r1 by a predetermined distance (S26: Yes), the vehicle control device <NUM> returns the work vehicle <NUM> from the avoidance route r1 to the original target route R (work route Rb), and causes the work vehicle <NUM> to resume automatic traveling along the target route R (S27).

As another embodiment, in a case where the work vehicle <NUM> has traveled along the avoidance route r1 for a predetermined time, the vehicle control device <NUM> may return the work vehicle <NUM> from the avoidance route r1 to the original target route R (work route Rb). The predetermined distance and the predetermined time may be set based on a traveling distance and a traveling time required for the work vehicle <NUM> to pass an object to be avoided, for example, in a case where the object to be avoided is an object to be avoided such as a water intake, whose outer shape can be generally recognized.

Other processing in automatic traveling processing according to the second embodiment is the same as that in automatic traveling processing according to the first embodiment.

Also in the automatic traveling system <NUM> according to the second embodiment, similarly to the automatic traveling system <NUM> according to the first embodiment, even in a case where the work vehicle <NUM> approaches the ridge A1, it is possible to cause the work vehicle <NUM> to automatically travel along the avoidance route r1 away from the ridge A1. Therefore, it is possible to continue automatic traveling without stopping the work vehicle <NUM>. Thus, since it is possible to cause the work vehicle <NUM> to automatically travel within the entirety of the field F, work efficiency of the work vehicle <NUM> can be improved.

Note that, an object to be avoided according to the present invention is not limited to the ridge A1, but may be a water intake or a fixed object located near a boundary of the field F. Also, an object to be avoided according to the present invention may be an obstacle that is difficult to be detected at a time of registering the field F, unlike an obstacle (structure such as a steel tower) that can be detected at a time of registering the field F.

In the first and second embodiments described above, the vehicle control device <NUM> may output a warning sound, in each of a case where the ridge A1 is detected, a case where the work vehicle <NUM> automatically travels along the avoidance route r1, and a case where the work vehicle <NUM> returns from the avoidance route r1 to the target route R. The vehicle control device <NUM> may also output a warning sound in a different manner between a warning sound in a case where an obstacle is the ridge A1, and a warning sound in a case where an obstacle is an object (such as a person) other than the ridge A1. The vehicle control device <NUM> may also output an audio guidance. For example, the vehicle control device <NUM> may output an audio sound "the ridge A1 has been detected", in a case where the ridge A1 has been detected, and may continuously output an audio sound "the work vehicle <NUM> is traveling along the avoidance route" until the work vehicle <NUM> returns to the original target route R, while the work vehicle <NUM> is automatically traveling along the avoidance route r1.

In the first and second embodiments described above, the obstacle detection unit <NUM> may be further provided in front of the vehicle body unit <NUM>. This enables to detect an obstacle in a forward direction of the work vehicle <NUM>. For example, when the work vehicle <NUM> turns and travels along the work route Rb on the outermost periphery of the field F, in a case where the obstacle detection unit <NUM> in the forward direction detects an obstacle, and the obstacle is the ridge A1, the vehicle control device <NUM> may cause the work vehicle <NUM> to turn and travel along an avoidance route (avoidance turning route) that is offset from the work route Rb.

Claim 1:
An automatic traveling method comprising:
Causing (S12, S22) a work vehicle (<NUM>) to automatically travel along a target route (R) set within a field (F);
Detecting (S13, S23) an obstacle (A1) located on an outer periphery of the field (F), while the work vehicle (<NUM>) is traveling along the target route (R) in an outer peripheral area (Fb) of the field (F); and
in a case where the obstacle (A1) is an object to be avoided, causing (S15, S25) the work vehicle (<NUM>) to travel along an avoidance route (r1) that is located more inside the field (F) than the target route (R),
characterized in the method further comprising:
in a case where an operator boards the work vehicle (<NUM>), determining that the obstacle (A1) is the object to be avoided in a case where a distance between the work vehicle (<NUM>) and the obstacle (A1) becomes equal to or less than a first set distance, and
in a case where an operator does not board the work vehicle (<NUM>), determining that the obstacle (A1) is the object to be avoided in a case where the distance between the work vehicle (<NUM>) and the obstacle (A1) becomes equal to or less than a second set distance being greater than the first set distance.