Work vehicle control method, work vehicle control program, work vehicle control system, and work system

Abstract

To provide a work vehicle control method, a work vehicle control program, a work vehicle control system, and a work system that can easily maintain control accuracy of a work vehicle.SOLUTION: A control method for a work vehicle 10 includes acquiring a first measurement value and a second measurement value on the basis of an output of a measuring device 14, and determining a deviation of an inclination angle of the work vehicle 10 from a normal value on the basis of a comparison result between the first measurement value and the second measurement value. The measuring device 14 is mounted on the work vehicle 10 and measures an inclination angle of the work vehicle 10 relative to a reference posture. The first measurement value is a value related to the inclination angle of the work vehicle 10 during a first measurement period, and the second measurement value is a value related to the inclination angle of the work vehicle 10 during a second measurement period.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a control method for a work vehicle equipped with a measurement device that measures the tilt angle of the work vehicle relative to a reference attitude, a control program for a work vehicle, a control system for a work vehicle, and a work system. [Background technology]

[0002] As a related technology, an automatic driving system that automatically drives a work vehicle (tractor) is known (see, for example, Patent Document 1). In the related technology, an on-board electronic control unit mounted on the work vehicle receives an instruction to start automatic driving, and performs automatic driving control to automatically drive the work vehicle along a target driving route while acquiring its current position using a positioning unit.

[0003] Here, the positioning unit has a satellite navigation device that measures the current position of the work vehicle, as well as an inertial measurement unit (IMU) that has a three-axis gyroscope, a three-directional acceleration sensor, etc. and measures the attitude of the work vehicle, etc. Therefore, for example, when traveling on a slope, it is conceivable to correct the current position of the work vehicle in accordance with the slope angle of the work vehicle, thereby reducing errors in the current position of the work vehicle caused by the slope of the work vehicle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-149472 Summary of the Invention [Problem to be solved by the invention]

[0005] In the configuration of the above-mentioned related technology, for example, if the measuring device (inertial measurement device) is installed crookedly, the tilt angle of the work vehicle measured by the measuring device may deviate from the normal value, which may lead to an error in the current position of the work vehicle and affect the control accuracy of the work vehicle.

[0006] An object of the present invention is to provide a control method for a work vehicle, a control program for a work vehicle, a control system for a work vehicle, and a work system that make it easy to maintain the control accuracy of the work vehicle. [Means for solving the problem]

[0007] A method for controlling a work vehicle according to one aspect of the present invention includes obtaining a first measurement value for the inclination angle of the work vehicle during a first measurement period and a second measurement value for the inclination angle of the work vehicle during a second measurement period based on the output of a measurement device mounted on the work vehicle that measures the inclination angle of the work vehicle relative to a reference attitude, and determining a deviation of the inclination angle of the work vehicle from a normal value based on a comparison result between the first measurement value and the second measurement value.

[0008] A work vehicle control program according to one aspect of the present invention is a program for causing one or more processors to execute the work vehicle control method.

[0009] A work vehicle control system according to one aspect of the present invention includes an acquisition processing unit and an arithmetic processing unit. The acquisition processing unit acquires a first measurement value relating to the inclination angle of the work vehicle during a first measurement period and a second measurement value relating to the inclination angle of the work vehicle during a second measurement period based on the output of a measurement device mounted on the work vehicle that measures the inclination angle of the work vehicle relative to a reference attitude. The arithmetic processing unit determines the deviation of the inclination angle of the work vehicle from a normal value based on a comparison result between the first measurement value and the second measurement value.

[0010] A work system according to one aspect of the present invention includes the work vehicle control system and a vehicle body on which the measuring device is mounted. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a work vehicle control method, a work vehicle control program, a work vehicle control system, and a work system that make it easy to maintain the control accuracy of the work vehicle. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a schematic side view showing the appearance of a work vehicle according to a first embodiment. [Figure 2] FIG. 2 is a schematic block diagram of the operation system according to the first embodiment. [Figure 3] FIG. 3 is a schematic diagram illustrating the automatic traveling in the work system according to the first embodiment. [Figure 4] FIG. 4 is a schematic diagram illustrating the tilt angle in the roll angle direction of the work vehicle according to the first embodiment. [Figure 5] FIG. 5 is a schematic diagram showing an example of a measurement route in the work vehicle control method according to the first embodiment. [Figure 6] FIG. 6 is an explanatory diagram showing an example of processing related to the inclination angle deviation calculation process in the work vehicle control method according to the first embodiment. [Figure 7] FIG. 7 is a graph showing an example of an inclination angle measured by a measurement device, in relation to the inclination angle deviation calculation process in the work vehicle control method according to the first embodiment. [Figure 8] FIG. 8 is a flowchart showing an example of processing related to the inclination angle deviation calculation process in the work vehicle control method according to the first embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following description will discuss preferred embodiments of the present invention with reference to the accompanying drawings. The preferred embodiments are merely examples of the present invention and are not intended to limit the technical scope of the present invention.

[0014] (Embodiment 1) [1] Overall structure First, the overall configuration of a work system 100 according to this embodiment will be described with reference to Figures 1 to 3. A work vehicle control system 1 according to this embodiment (hereinafter also simply referred to as "control system 1") constitutes the work system 100 together with a body 11 of a work vehicle 10. A work implement 12 is attached to the body 11. In other words, the work system 100 comprises the work vehicle control system 1 and the body 11 of the work vehicle 10 (to which the work implement 12 is attached).

[0015] In this embodiment, the control system 1 includes a control device 2 (see FIG. 2 ) mounted on the body 11 of the work vehicle 10, and a terminal device 3. The work vehicle 10 and the terminal device 3 are capable of communicating with each other. In this disclosure, "capable of communication" means that information can be exchanged directly or indirectly via a communication network or repeater, using an appropriate communication method such as wired communication or wireless communication (communication using radio waves or light as a medium). Examples of communication networks include the Internet, a LAN (Local Area Network), a WAN (Wide Area Network), a public telephone line, a mobile phone network, a packet network, or a wireless LAN. It is not essential for the control system 1 that the work vehicle 10 and the terminal device 3 are capable of communicating with each other.

[0016] The work vehicle 10 moves through a target area F1 (see FIG. 1 ) while performing some kind of work within the target area F1 using the work implement 12. In this disclosure, "work" refers to a job that the work implement 12 performs on the target area F1, and includes, for example, various types of agricultural work such as plowing, leveling, sowing, fertilizing, spraying pesticides, planting (rice planting) or harvesting, as well as construction work. In this embodiment, as an example, the work performed by the work vehicle 10 is plowing.

[0017] The work implement 12 performs work within the target area F1 when the body 11 of the work vehicle 10 moves through the target area F1. In this embodiment, as an example, the work implement 12 is a tiller such as a rotary tiller or plow that performs tilling work.

[0018] This type of work implement 12 includes a directly mounted work implement that is attached directly to a three-point linkage, and a towed work implement that is towed by the machine body 11. In this embodiment, as an example, the work implement 12 is a directly mounted rotary tiller that is detachably attached to the machine body 11 of the work vehicle 10. Here, the work implement 12 is attached to the rear side of the machine body 11 (the side opposite to the forward direction of the machine body 11). In other words, the (directly mounted) work implement 12 is connected to the rear side of the machine body 11, and performs work while moving forward together with the machine body 11 when the machine body 11 moves forward. In this embodiment, the work implement 12 is considered to be included as a component of the work vehicle 10, but because the work implement 12 is detachable from the machine body 11, it does not have to be included as a component of the work vehicle 10.

[0019] In the present disclosure, the term "work vehicle" refers to a vehicle that performs various tasks in a target area F1, such as a farm field, and examples include agricultural machinery (farm machinery) such as a tractor, a seed drill, a rice transplanter, a spreader, a sprayer, a transplanter, and a harvester. The work vehicle 10 may also be, for example, a construction machine (construction equipment). In this embodiment, unless otherwise specified, the work vehicle 10 will be described as a tractor equipped with a rotary tiller as the work implement 12. In other words, the work vehicle 10 is configured by connecting a (direct-mounted) rotary tiller as the work implement 12 to a tractor as the machine body 11. With this work vehicle 10, tilling work can be performed in the target area F1, such as a farm field, by the machine body 11 traveling through the target area F1.

[0020] As described above, in this embodiment, the machine body 11 is a type of vehicle that moves by traveling through the target area F1. Here, as shown in Figures 1 and 3, the machine body 11 has steering wheels 111 consisting of a pair of left and right front wheels, and driving wheels 112 consisting of a pair of left and right rear wheels, and travels through the target area F1 using these four wheels (the pair of steering wheels 111 and the pair of driving wheels 112).

[0021] In addition, in this embodiment, as an example, the work vehicle 10 is an automated machine that can operate by automatic travel (autonomous travel, etc.) while allowing a person (operator) to ride in. However, the work vehicle 10 is not limited to this, and may be an unmanned machine that automatically travels, or may be operated by operation (including remote control) by a person (operator).

[0022] In the present disclosure, the term "target area" refers to an area in which the work vehicle 10 travels and performs various tasks, such as plowing, leveling, sowing, fertilizing, spraying pesticides, planting (rice transplanting), or harvesting, and includes paddy fields, fields, orchards, pastures, and the like. For example, if the target area F1 is a paddy field or field where crops (agricultural products) such as rice, wheat, soybeans, or buckwheat are grown, the crops grown in the target area F1 are agricultural products. Furthermore, if plants are grown in a nursery, the nursery is the target area F1, and if trees for lumber are grown in a forest, as in forestry, the forest is the target area F1. In this case, the crops grown in the target area F1 are plants, trees, or the like. In this embodiment, unless otherwise specified, the work vehicle 10 is used for plowing a field (target area F1), and the target area F1 is a rice paddy for growing rice, as an example. Furthermore, the target area F1 is not limited to a farm field. For example, if the work vehicle 10 is a construction machine, the target area F1 would be a site where the construction machine is working.

[0023] Furthermore, the work vehicle 10 can move by automatic driving not only within the target area F1 (here, a field), but also on roads outside the target area F1, such as roads outside the field. The work vehicle 10 is configured to be able to automatically drive (move) along target routes (including roads outside the field) set in advance within and outside the target area F1, based on position information of the current position of the work vehicle 10 measured by a positioning device 15 (see FIG. 2). An outside-field route is, for example, an inter-field connecting road that connects multiple target areas F1 (fields). An inter-field connecting road may be a farm road, forest road, public road, private road, or highway, and may be a road exclusively for the work vehicle 10, or a road that is passable by general vehicles (passenger cars, etc.).

[0024] Furthermore, "automatic driving" as referred to in this disclosure includes "autonomous driving" in which the work vehicle 10 drives autonomously without the operation of an operator, and "semi-automatic driving" in which only steering is automated, such as straight-line assist.

[0025] "Autonomous driving" is a driving mode in which, for example, the steering wheels 111 are automatically steered and vehicle speed and other controls are also performed automatically so that the work vehicle 10 travels along a target route R1, as shown on the left side of FIG. 3. "Straight-line assist" is a driving mode in which, for example, the steering wheels 111 are automatically steered so that the work vehicle 10 travels along a linear target route R1 parallel to a reference straight line (reference line), as shown on the right side of FIG. 3. In other words, "semi-automatic driving" is a driving mode in which only the steering wheels 111 are automatically steered and vehicle speed and other controls are controlled by the operator's operation, so that the work vehicle 10 travels along a linear target route R1 parallel to a reference straight line (reference line). In other words, while "semi-automatic driving" does not allow the work vehicle 10 to travel without the operator's operation, it reduces the steering burden on the operator and allows the work vehicle 10 to travel along a target route such as a straight route, leading to improved work efficiency. In both autonomous driving and semi-automatic driving, the steering wheels 111 are automatically steered, so this can be said to be one aspect of "automatic steering mode."

[0026] In the automatic steering mode, the steering wheels 111 are automatically steered by a motor. That is, instead of an operator operating the steering handle 41 (see FIG. 1), automatic steering is achieved by changing the direction of the steering wheels 111 using the output of the motor. In short, the work vehicle 10 according to this embodiment has an automatic steering mode in which the steering wheels are automatically steered using a motor.

[0027] [2] Configuration of work vehicles Next, the configuration of the work vehicle 10 according to this embodiment will be described in detail with reference to FIGS.

[0028] In this embodiment, for ease of explanation, the vertical direction when the work vehicle 10 is in a usable state is defined as the up-down direction D1 (see FIG. 1). The front-to-rear direction D2 and the left-to-right direction D3 (see FIG. 4) are defined based on the direction as seen by a person (operator) riding on the body 11 (of the driving section 113) of the work vehicle 10. The left side of the left-to-right direction D3 refers to the left side when the body 11 is traveling forward (advancing), and the right side of the left-to-right direction D3 refers to the right side when the body 11 is traveling forward (advancing). However, these directions are not intended to limit the direction of use of the work vehicle 10 (direction during use).

[0029] 2, the work vehicle 10 is equipped with a control device 2, a traveling device 13, a measuring device 14, a positioning device 15, a detection device 16, a communication device 17, a power source 18, an operation device 19, etc. in addition to a machine body 11 and a work implement 12. The control device 2, the traveling device 13, the measuring device 14, the positioning device 15, the detection device 16, the communication device 17, the power source 18, and the operation device 19 are all mounted on the machine body 11. In this embodiment, as an example, the measuring device 14 and the positioning device 15 are housed in a single case as an antenna unit 20.

[0030] The machine body 11 has a driving section 113 (see Figure 1) in which a person (operator) can ride. The driving section 113 is provided with a steering wheel 41 (see Figure 1), a gear shift lever, an operating device 19, etc. The steering wheel 41, the gear shift lever, and the operating device 19, etc. are operating sections that are operated by the operator. Therefore, the work vehicle 10 is configured to be capable of not only automatic driving, but also manual driving by manual operation by the operator. Also, as described above, the work implement 12 is removably connected to the rear side of the machine body 11. It is also possible to connect a device other than the work implement 12 to the machine body 11.

[0031] In this embodiment, the work implement 12 is a directly mounted rotary tiller, and is therefore capable of tilling the field serving as the target area F1 when the machine body 11 moves forward. The work implement 12 is variable in its position (relative height) relative to the machine body 11 in the up-down direction D1. This makes it possible to vary the height of the work implement 12 when the field scene, which is the ground surface of the target area F1, is used as a reference, and for example, by raising the work implement 12 to a height that separates it from the ground surface of the target area F1, the work vehicle 10 can travel in a non-working state in which the work implement 12 is not performing work.

[0032] As shown in FIG. 1 , the traveling device 13 is a device that drives drive wheels 112 consisting of (a pair of left and right) rear wheels, thereby causing the work vehicle 10 to travel. The traveling device 13 includes a transmission, and transmits power generated by the power source 18 to the drive wheels 112 via the transmission, thereby causing the machine body 11 to travel forward or backward. Furthermore, the traveling device 13 includes a brake device, and is also capable of slowing down or stopping the machine body 11. In this embodiment, the drive wheels 112 are normal wheels, but this is not limiting, and the machine body 11 may, for example, be a half-crawler type machine body 11 that uses crawlers (tracks) for the drive wheels 112.

[0033] Furthermore, as shown in FIG. 1, the traveling device 13 steers the steering wheels 111 consisting of (a pair of left and right) front wheels. The traveling device 13 steers the steering wheels 111 in response to the operator's operation of the steering handle 41. The pair of steering wheels 111 have a straight-ahead position in a plan view in which they face the front-to-rear direction D2, that is, a position in which the rotation axis is along the left-to-right direction D3, and are steered by the traveling device 13 so as to tilt left or right from the straight-ahead position. In other words, the traveling device 13 steers the steering wheels 111 by changing the direction of the pair of steering wheels 111.

[0034] The traveling device 13 enables the vehicle 11 to travel within the target area F1 in the forward / backward direction D2 and the left / right direction D3. For example, when the driving wheels 112 are driven by the traveling device 13 to move the vehicle 11 forward, if the angle of the steering wheels 111 is changed, the vehicle 11 turns in the left / right direction D3, and the traveling direction of the vehicle 11 is changed.

[0035] The measurement device 14 is mounted on the body 11 of the work vehicle 10 and is a device that measures the tilt angle of the work vehicle 10 with respect to a reference attitude. Specifically, the measurement device 14 is disposed, for example, on the roof of the driver's section 113. The measurement device 14 is, for example, an inertial measurement unit (IMU) that has a three-axis angular velocity sensor (gyro sensor) that is orthogonal to one another and a three-axis acceleration sensor that is orthogonal to one another, and measures the attitude, etc. of the work vehicle 10. This measurement device 14 is capable of detecting three-dimensional inertial motion (rotational motion and translational motion in three orthogonal axial directions), and measures the rotation angle (tilt angle) around the three axes due to the rotational motion using the angular velocity sensor, and measures the three-axis acceleration due to the translational motion using the acceleration sensor.

[0036] The positioning device 15 determines the current position (latitude, longitude, altitude, etc.) of the aircraft 11. Specifically, the positioning device 15 is disposed, for example, on the roof of the driver's section 113, and calculates the current position (latitude and longitude) of the aircraft 11 using a satellite positioning system such as the Global Navigation Satellite System (GNSS). That is, the positioning device 15 has a positioning antenna that receives positioning signals from multiple satellites 202 (see FIG. 1), and calculates the current position based on the positioning signals.

[0037] The positioning device 15 also employs a relatively high-precision positioning method such as RTK (Real Time Kinematic) positioning, which calculates the current position of the work vehicle 10 using correction information corresponding to a base station 201 (reference station) close to the work vehicle 10. The current position of the vehicle 11 may be the same as the positioning position (position of the positioning antenna), or may be a position displaced from the positioning position, such as the center position of the vehicle 11 in a planar view. The positioning device 15 may be substituted with, for example, a mobile phone terminal, a smartphone, or a tablet terminal.

[0038] The antenna unit 20 having the measuring device 14 and positioning device 15 described above is disposed at the front end of the roof of the driver's section 113, in the center of the left-right direction D3 (see FIGS. 1 and 4). Therefore, the current position of the aircraft 11 measured by the positioning device 15 is identified by the position of positioning point P0 (see FIG. 4), which is located at the front end of the roof of the driver's section 113, in the center of the left-right direction D3.

[0039] The detection device 16 detects obstacles in the detection area. The detection device 16 includes an obstacle sensor and a detection processing unit. The obstacle sensor may include various sensors such as a camera (image sensor), a sonar sensor, a human presence sensor, radar, or LiDAR (Light Detection and Ranging). The obstacle sensor may be a three-dimensional sensor that measures the distance to an object (obstacle) using a Time Of Flight (TOF) method, which measures the distance to a ranging point based on the round-trip time it takes for light or sound to reach the ranging point and return. The detection processing unit detects obstacles based on measurement information acquired from the obstacle sensor. Here, the detection processing unit may detect only the presence or absence of an obstacle, or may detect the position, shape, number, or attributes (including type, etc.) of the obstacle.

[0040] The detection results of the detection device 16 are output to the control device 2. When the detection device 16 detects an obstacle at least during the automatic traveling of the work vehicle 10, the control device 2 outputs an alarm (including an alarm by sound and / or light) and executes obstacle avoidance processing (including detouring, slowing down, stopping, etc.) by controlling the traveling device 13. Furthermore, the control device 2 may output obstacle position information, the execution history of the avoidance processing, etc. to the terminal device 3 and cause the terminal device 3 to display, etc.

[0041] The communication device 17 is a communication interface that connects the work vehicle 10 (control device 2, positioning device 15, etc.) to an external device via a wired or wireless connection and executes data communication with the external device in accordance with a predetermined communication protocol. In this embodiment, the communication device 17 is capable of mutual communication with at least the external device, the terminal device 3. For example, a mobile phone terminal, a smartphone, a tablet terminal, etc. may be used as the communication device 17.

[0042] The power source 18 is a driving source that supplies power to at least the traveling device 13. The power source 18 has an engine such as a diesel engine.

[0043] The operation device 19 is a device that accepts operations from an operator. The operation device 19 can accept, for example, a switching operation between an automatic steering mode in which the steering wheels 111 are automatically steered and a manual steering mode in which the steering wheels 111 are manually steered. The operation device 19 outputs a signal to the control device 2 according to the accepted operation.

[0044] The control device 2 is primarily configured as a computer system having one or more processors such as a CPU (Central Processing Unit) and one or more memories such as a ROM (Read Only Memory) and a RAM (Random Access Memory), and performs various processes (information processing). In this embodiment, the control device 2 is primarily configured as a computer system having one or more processors, and the control device 2 is realized by the one or more processors executing a work vehicle control program. In this embodiment, the control device 2 is an integrated controller that controls the entire work vehicle 10, and is composed of, for example, an electronic control unit (ECU). However, the control device 2 may be provided separately from the integrated controller.

[0045] The control device 2 is configured to be able to communicate with devices provided in each part of the machine body 11. In other words, the control device 2 is electrically connected to the work implement 12, the traveling device 13, the measuring device 14, the positioning device 15, the detecting device 16, the communication device 17, the power source 18, the operating device 19, etc. This allows the control device 2 to control the work implement 12, the traveling device 13, etc., and to acquire outputs from the measuring device 14, the positioning device 15, the detecting device 16, the operating device 19, etc. Here, the control device 2 may exchange various types of information (data) with each device directly, or indirectly via a repeater or the like.

[0046] In this embodiment, the control device 2 includes a travel control unit 21, an operation control unit 22, a storage unit 23, an acquisition processing unit 24, and an arithmetic processing unit 25, as shown in FIG.

[0047] The travel control unit 21 controls the travel device 13 and the power source 18. At least during autonomous travel, the travel control unit 21 controls the travel device 13 and the power source 18 on behalf of the operator so that the vehicle speed, engine rotation speed, etc. approach target values. The travel control unit 21 can also control the brake device of the travel device 13 to slow down or stop the vehicle 11.

[0048] The driving control unit 21 further controls the steering angle of the steered wheels 111. The driving control unit 21 has an automatic steering mode and a manual steering mode as its operating modes, and is configured to be able to switch between the automatic steering mode and the manual steering mode. The manual steering mode is a mode in which the operator performs steering by operating the steering wheel 41. The driving control unit 21 operates in the automatic steering mode at least during autonomous driving or semi-automatic driving, and controls the steering angle of the steered wheels 111 to approach the target steering angle on behalf of the operator.

[0049] In particular, during autonomous driving, the driving control unit 21 controls the work vehicle 10 based on the current position of the machine body 11 so that the machine body 11 drives along the target route. The target route for the work vehicle 10 to drive autonomously is generated, for example, in the terminal device 3. That is, the work vehicle 10 acquires route data corresponding to the target route from the terminal device 3 and drives autonomously according to the target route.

[0050] The work control unit 22 controls the work implement 12. At least during autonomous driving, the work control unit 22 controls the work implement 12 based on the current position of the vehicle body 11 on the target route. Specifically, if the work vehicle 10 is traveling on a work route of the target route where work is to be performed by the work implement 12, the work control unit 22 sets the work implement 12 to a work position and performs work by the work implement 12. On the other hand, if the work vehicle 10 is traveling on a non-work route of the target route where work is not to be performed by the work implement 12, the work control unit 22 raises the work implement 12 to a non-work position and stops work by the work implement 12.

[0051] The storage unit 23 is a non-volatile memory or the like that stores various data such as a work vehicle control program and target route information related to the target route. In other words, the traveling control unit 21 can, for example, cause the vehicle to autonomously travel along the target route based on the target route information stored in the storage unit 23.

[0052] The acquisition processing unit 24 acquires first and second measurement values ​​based on the output of the measuring device 14. The first measurement value is a value related to the inclination angle of the work vehicle 10 during the first measurement period. The second measurement value is a value related to the inclination angle of the work vehicle 10 during the second measurement period. In this embodiment, as an example, the first measurement value is the average value of the inclination angle of the work vehicle 10 during the first measurement period. Similarly, the second measurement value is the average value of the inclination angle of the work vehicle 10 during the second measurement period.

[0053] The calculation processing unit 25 determines the deviation of the tilt angle of the work vehicle 10 from the normal value using the first measurement value and the second measurement value acquired by the acquisition processing unit 24. Here, the calculation processing unit 25 determines the deviation of the tilt angle of the work vehicle 10 from the normal value based on the comparison result between the first measurement value and the second measurement value.

[0054] Furthermore, in this embodiment, the calculation processing unit 25 performs a "correction" based on the deviation from the normal value of the inclination angle of the work vehicle 10. Specifically, the calculation processing unit 25 corrects the deviation of the inclination angle of the work vehicle 10 measured by the measuring device 14, and as a result, corrects the current position of the work vehicle 10 determined from the output of the positioning device 15.

[0055] In addition to the above-mentioned configuration, the work vehicle 10 is further equipped with a battery, a fuel tank, a display device, various sensors, etc. The battery supplies operating power to each part of the work vehicle 10, such as the control device 2. In particular, electronic devices such as the control device 2, measuring device 14, positioning device 15, detection device 16, and communication device 17 operate using power supplied from the battery, and can therefore operate even when the power source 18 is stopped. The display device is a user interface for presenting information to the user (operator), such as a liquid crystal display or organic EL display that displays various types of information.

[0056] [3] Terminal device configuration Next, the configuration of the terminal device 3 according to this embodiment will be described in detail with reference to FIGS.

[0057] In this embodiment, the terminal device 3 is capable of communicating with the work vehicle 10 as described above, and constitutes the control system 1 together with the control device 2 of the work vehicle 10. In other words, the components of the control system 1 are distributed across at least the work vehicle 10 and the terminal device 3. However, this configuration is not limiting, and for example, the functions of the terminal device 3 may be provided in the control device 2, in which case the components of the control system 1 would be realized by the control device 2 alone.

[0058] In this embodiment, as an example, the terminal device 3 is configured as a general-purpose terminal such as a tablet terminal, a smartphone, or a laptop computer. As shown in Fig. 1, the terminal device 3 is disposed in the driving section 113 of the machine body 11. Dedicated application software (program) is installed in the terminal device 3 configured as a general-purpose terminal, and by starting this application software, the terminal device 3 functions as the terminal device 3 of the control system 1.

[0059] The terminal device 3 includes a display unit 31 and an operation unit 32. The display unit 31 includes, for example, a liquid crystal display or an organic EL display. The operation unit 32 includes, for example, a touch panel, a physical switch, a mouse, or a keyboard. In the present embodiment, as an example, the display unit 31 made of a liquid crystal display and the operation unit 32 made of a touch panel are integrated to form a touch panel display. Therefore, by operating the operation unit 32 while a display screen is displayed on the display unit 31, the terminal device 3 can accept user operations on the display screen.

[0060] The terminal device 3 is used to input various settings related to the operation of the work vehicle 10 and to output control signals related to the control of the work vehicle 10. Specifically, the terminal device 3 has the function of setting (registering) various information related to the control of the work vehicle 10, such as a target route for the automatic driving of the work vehicle 10. In other words, the operator can set the target route, etc. by operating the operation unit 32 on the display screen displayed on the display unit 31. The information set here, such as the target route, is transmitted directly or indirectly to the work vehicle 10 and used for the automatic driving of the work vehicle 10. Furthermore, the terminal device 3 is configured to be able to operate the work vehicle 10 by outputting (transmitting) to the work vehicle 10 a control signal for at least stopping the automatic driving of the work vehicle 10 in response to operation by the operator.

[0061] Furthermore, while the work vehicle 10 is autonomously traveling, the terminal device 3 can display on the display unit 31 various information related to the operation of the work vehicle 10, such as the current position, current orientation, and (spraying) work status of the work vehicle 10. As an example, the terminal device 3 can display on the display unit 31 a monitoring screen that displays the current position of the work vehicle 10, etc., together with the target route on a map that simulates the target area F1, making it easier for the operator to visually grasp the status of the work vehicle 10.

[0062] [4] Control method for work vehicles Next, with reference to FIGS. 3 to 8, an example of a control method for the work vehicle 10 (hereinafter simply referred to as "control method") that is executed mainly by the control system 1 will be described.

[0063] The control method according to this embodiment is executed by a control system 1 whose main component is a computer system, and in other words, is embodied in a work vehicle control program (hereinafter simply referred to as a "control program"). In other words, the control program according to this embodiment is a computer program that causes one or more processors to execute each process related to the control method.

[0064] Here, the control system 1 executes the following various processes related to the control method when a specific, preset start operation is performed to execute the control program. The start operation is, for example, an ON operation of a key switch to start the engine (power source 18) and / or an operation to launch an application program (control program for a work vehicle) on the terminal device 3. On the other hand, the control system 1 terminates the following various processes related to the control method when a specific, preset end operation is performed. The end operation is, for example, an OFF operation of a key switch and / or an operation to terminate the application program (control program for a work vehicle) on the terminal device 3.

[0065] [4.1] Automatic driving method First, a method for causing the work vehicle 10 to travel automatically (including autonomous and semi-autonomous travel) using the control system 1 according to this embodiment will be described with reference to Fig. 3. Fig. 3 schematically shows a target route R1 generated for a target area F1 in a plan view and the work vehicle 10. In Fig. 3, a route along which the work vehicle 10 performs work (work route r11) is indicated by a solid line, and a route along which the work vehicle 10 does not perform work (non-work route r12) is indicated by a dotted line.

[0066] The left side of FIG. 3 shows an example of autonomous driving in which the work vehicle 10 travels autonomously without operator operation. In autonomous driving, the control system 1 automatically drives the work vehicle 10 along a target route R1 generated for a target area F1 consisting of a farm field. In the example of FIG. 3, the target route R1 includes a plurality of linear work routes r11 and a non-work route r12 consisting of a turning route connecting adjacent work routes r11. In this case, the control system 1 controls the traveling device 13 (including the steering wheels 111) and the power source 18 using the traveling control unit 21 to drive the work vehicle 10 along the target route R1. Furthermore, the control system 1 controls the work implement 12 using the work control unit 22 to perform work by the work implement 12 only along the work route r11 of the target route R1.

[0067] The right side of Figure 3 shows an example of straight-line assist (semi-automated driving) in which only steering is automated. In straight-line assist, the control system 1 causes the work vehicle 10 to travel along a target route R1 consisting of a straight-line route r13 parallel to a reference line in a target area F1 consisting of a farm field. In this case, the control system 1 controls the steering angle of the steered wheels 111 using the travel control unit 21 to keep the work vehicle on the straight-line route r13.

[0068] In this example, at least when the work vehicle 10 deviates from the straight path r13, the travel control unit 21 changes the steering angle of the steered wheels 111 in order to return the work vehicle 10 to the straight path r13.

[0069] When performing the above-described automatic driving (including autonomous driving and semi-automatic driving), the work vehicle 10 moves along the target route R1 based on position information of the current position of the work vehicle 10 measured by the positioning device 15. Therefore, for example, as shown on the left side of FIG. 4, when the work vehicle 10 travels through a target area F1 that is inclined in the roll direction, the center position P1 of the work vehicle 10 in the left-right direction D3 on the surface of the target area F1 may deviate from the target route R1 in the left-right direction D3. The "roll direction" referred to in this disclosure is the direction of rotation (tilt) of the vehicle body 11 around an axis along the traveling direction of the work vehicle 10 (i.e., the fore-aft direction D2). When the work vehicle 10 tilts in the roll direction, the vehicle body 11 is in a "downward right" state, where the right side of the vehicle body 11 is lowered, or in a "downward left" state, where the left side of the vehicle body 11 is lowered.

[0070] That is, as shown on the left side of FIG. 4, in a plan view, a positioning position P2 drawn by a perpendicular line from the positioning point P0 where the antenna unit 20 (positioning device 15) is located (i.e., directly below the vertical direction of the positioning point P0) is recognized as the current position of the work vehicle 10, whose position is determined by the positioning device 15. Therefore, when automatic driving control is performed so that the positioning position P2 is on the target route R1, the center position P1 (in the left-right direction D3) of the work vehicle 10 will be shifted in the left-right direction D3 from the target route R1. In the example of FIG. 4, since the target area F1 is tilted in the roll direction, the vehicle body 11 is tilted downward to the right, and therefore the center position P1 of the work vehicle 10 is shifted to the left from the positioning position P2 by a shift amount L1. The shift amount L1 varies depending on the tilt angle in the roll direction of the work vehicle 10, and the greater the tilt angle, the greater the shift amount L1. In particular, when the work vehicle 10 travels back and forth as in the example shown on the left side of FIG. 3, the influence of this amount of deviation L1 may result in unworked areas in the target area F1.

[0071] In the control method according to this embodiment, automatic driving is performed by shifting the measured position P2 in the left-right direction D3 by an amount equivalent to the deviation amount L1 in order to suppress deviation of the center position P1 of the work vehicle 10 from the target route R1. In other words, by performing an "offset adjustment process" that shifts the measured position P2 in the left-right direction D3 in accordance with the tilt angle in the roll direction of the work vehicle 10, it is possible to adjust the center position P1 (in the left-right direction D3) of the work vehicle 10 to be on the target route R1. The tilt angle in the roll direction of the work vehicle 10 is measured by the measuring device 14, so during the offset adjustment process, the driving control unit 21 adjusts the actual driving position with respect to the target route R1 based on the measurement results of the measuring device 14.

[0072] On the other hand, depending on the mounting state of the antenna unit 20 on the vehicle body 11, performing the offset adjustment process as described above may result in the center position P1 of the work vehicle 10 being deviated from the target route R1. For example, in the example shown on the right side of Fig. 4, the antenna unit 20 (measurement device 14) is mounted tilted in the roll direction with respect to the vehicle body 11. Therefore, while offset adjustment processing is not normally required when traveling through a horizontal (non-tilted) target area F1, in the example on the right side of Fig. 4, the offset adjustment process causes the positioning position P2 to be deviated in the left-right direction D3 from the target route R1 by an amount equivalent to the amount of deviation L1 (which does not actually occur).

[0073] In this way, for example, if the measuring device 14 is installed crookedly, the tilt angle of the work vehicle 10 measured by the measuring device 14 may deviate from the normal value, which may result in an error in the current position of the work vehicle 10 and affect the control accuracy of the work vehicle 10.

[0074] In this embodiment, the deviation from the normal value of the inclination angle of the work vehicle 10 measured by the measuring device 14 is determined by the "inclination angle deviation calculation process" described below, thereby realizing a control method, a work vehicle control program, a work vehicle control system 1, and a work system 100 that make it easy to maintain the control accuracy of the work vehicle 10.

[0075] [4.2] Calculation of tilt angle deviation Next, the process related to the calculation of the deviation in the tilt angle in the control method according to this embodiment will be described with reference to FIGS.

[0076] In this embodiment, a measurement route R2 is generated, and the deviation of the tilt angle of the work vehicle 10 from the normal value is determined based on the output of the measuring device 14 when the work vehicle 10 travels automatically along this measurement route R2. As shown in Fig. 5, the measurement route R2 is a straight route connecting points A and B. The measurement route R2 may be used in combination with the target route R1 for automatic travel, or may be generated separately from the target route R1.

[0077] In the control method according to this embodiment, the work vehicle 10 is caused to travel back and forth along the same measurement route R2, and the deviation of the inclination angle of the work vehicle 10 from the normal value is determined based on the output of the measurement device 14 while traveling on both the outbound and inbound routes. Here, the travel route from point A to point B is referred to as the "outbound route," and the travel route from point B to point A is referred to as the "inbound route." A value related to the inclination angle of the work vehicle 10 while traveling on the outbound route is referred to as a first measured value, and a value related to the inclination angle of the work vehicle 10 while traveling on the inbound route is referred to as a second measured value, and the deviation of the inclination angle of the work vehicle 10 from the normal value is determined based on the results of comparing these first and second measured values.

[0078] In this way, the calculation processing unit 25 determines the deviation of the inclination angle of the work vehicle 10 from the normal value based on the comparison result between the first measurement value of the inclination angle of the work vehicle 10 during the first measurement period while the work vehicle 10 is traveling on the outbound path, and the second measurement value of the inclination angle of the work vehicle 10 during the second measurement period while the work vehicle 10 is traveling on the return path. Because the work vehicle 10 is made to travel both ways on the same measurement route R2, if the inclination angle of the work vehicle 10 is a normal value, the inclination angles measured on the outbound path and the return path should be opposite in the roll direction and have the same value. Therefore, the comparison result between the first measurement value and the second measurement value determines the deviation of the inclination angle of the work vehicle 10 from the normal value.

[0079] That is, the control method according to this embodiment comprises obtaining a first measurement value and a second measurement value based on the output of the measuring device 14, and determining the deviation of the inclination angle of the work vehicle 10 from a normal value based on the comparison result between the first measurement value and the second measurement value. The measuring device 14 is mounted on the work vehicle 10 and measures the inclination angle of the work vehicle 10 relative to a reference attitude. The first measurement value is a value related to the inclination angle of the work vehicle 10 during a first measurement period, and the second measurement value is a value related to the inclination angle of the work vehicle 10 during a second measurement period.

[0080] In this way, by acquiring the first and second measurement values ​​based on the output of the measuring device 14 during each of the first and second measurement periods and comparing these, it is possible to determine the deviation of the inclination angle of the work vehicle 10 from the normal value. As a result, by correcting the deviation of the inclination angle of the work vehicle 10 from the normal value, it is possible to adjust the center position P1 (in the left-right direction D3) of the work vehicle 10 to be on the target route R1 when performing the offset adjustment process as described above. Therefore, it is possible to realize a control method, work vehicle control program, work vehicle control system 1, and work system 100 that can determine the deviation of the inclination angle of the work vehicle 10 measured by the measuring device 14 from the normal value, and thereby easily maintain the control accuracy of the work vehicle 10.

[0081] Here, the tilt angle is the angle of tilt in the roll angle direction of the work vehicle 10. Therefore, for example, it becomes easier to maintain the control accuracy of the work vehicle 10 when performing an "offset adjustment process" that shifts the positioning position P2 in the left-right direction D3 according to the tilt angle in the roll direction of the work vehicle 10. Since a deviation in the tilt angle in the roll angle direction has a large effect on the positioning accuracy of the work vehicle 10 (particularly on the adjacent work route r11), determining the deviation in the tilt angle in the roll angle direction particularly improves the control accuracy of the work vehicle 10.

[0082] Furthermore, in this embodiment, the first measurement value is the average value of the inclination angle of the work vehicle 10 during the first measurement period, and the second measurement value is the average value of the inclination angle of the work vehicle 10 during the second measurement period. In other words, the calculation processing unit 25 averages the output of the measuring device 14 during the first measurement period while the work vehicle 10 is traveling on the outbound path, and calculates the first measurement value, which is the average value of the inclination angle of the work vehicle 10. Similarly, the calculation processing unit 25 averages the output of the measuring device 14 during the second measurement period while the work vehicle 10 is traveling on the return path, and calculates the second measurement value, which is the average value of the inclination angle of the work vehicle 10.

[0083] In this way, the deviation of the inclination angle of the work vehicle 10 from the normal value is determined using averaged measured values, which reduces the influence of temporary fluctuations in the output of the measuring device 14 due to, for example, localized irregularities or noise. Therefore, it is possible to determine the deviation of the inclination angle of the work vehicle 10 from the normal value with greater accuracy.

[0084] Furthermore, the control method according to this embodiment further comprises making a correction based on the deviation of the inclination angle of the work vehicle 10 from its normal value. In other words, the calculation processing unit 25 not only determines the deviation of the inclination angle from its normal value, but also corrects the output of the measuring device 14, etc., based on the determined deviation (and its magnitude). Specifically, the calculation processing unit 25 determines the amount of deviation of the inclination angle from its normal value and automatically stores this deviation amount in the memory unit 23 as a correction value. Thereafter, the calculation processing unit 25 corrects the output of the measuring device 14 (the inclination angle measured by the measuring device 14) in accordance with the correction value. Alternatively, the calculation processing unit 25 may correct the current position (positioning information) of the work vehicle 10 in accordance with the correction value.

[0085] As a result, even if the tilt angle of the work vehicle 10 measured by the measuring device 14 deviates from the normal value, the deviation can be corrected and control can be performed in the same way as if no deviation occurred. As a result, it becomes easier to maintain the control accuracy of the work vehicle 10. Furthermore, because the correction is performed automatically, there is no need for the operator to input the correction value, for example.

[0086] The tilt angle deviation calculation process in this embodiment will be described in more detail below.

[0087] In this embodiment, as shown in FIG. 5, the measurement route R2 includes three sections: a travel section R21, a run-up section R22, and a run-up section R23. The travel section R21 is a section set between the run-up section R22 and the run-up section R23. The run-up section R22 is a section a certain distance (for example, 5 m) from point A, and the run-up section R23 is a section a certain distance (for example, 5 m) from point B. Here, as an example, the travel section R21 is assumed to be a 15 m section. When the work vehicle 10 travels along the measurement route R2 (the travel section R21, the run-up section R22, and the run-up section R23), travel control of the work vehicle 10 is performed so that a point on the work vehicle 10 determined as a travel reference point moves on the travel route R2. The travel reference point is assumed to be the center of the pair of drive wheels 112 (the center of the rear axle in the left-right direction D3). However, the driving reference point is not limited to the center of the pair of drive wheels 112, but may be, for example, the center of the aircraft 11, the mounting position of the antenna unit 20 (positioning device 15), or the center of the pair of steering wheels 111, etc.

[0088] Here, sampling of the output of the measuring device 14 is performed only during the period when the work vehicle 10 is traveling on the travel section R21 of the measurement route R2, on both the outbound and return journeys. In other words, the period when the work vehicle 10 is traveling on the travel section R21 on the outbound journey is the first measurement period, and the period when the work vehicle 10 is traveling on the travel section R21 on the return journey is the second measurement period.

[0089] The approach sections R22 and R23 are sections for aligning the work vehicle 10 with respect to the measurement route R2. In other words, by correctly aligning the work vehicle 10 on the measurement route R2 while traveling through the approach sections R22 and R23, the reliability of the output of the measuring device 14 while traveling through the travel section R21 is improved.

[0090] FIG. 6 is a schematic diagram showing steps (first to fourth steps) related to the tilt angle deviation calculation process.

[0091] In the first step, the operator generates a measurement route R2 by registering points A and B in the target area F1, and manually drives the work vehicle 10 toward point A on the measurement route R2. With the work vehicle 10 on the measurement route R2 near point A, automatic driving is started. In this first step, it is preferable to display guidance to the operator on the display unit 31 of the terminal device 3, such as "Start roll angle correction," "Register points A and B," "Place the vehicle body on the route," or "Start automatic driving (outbound)."

[0092] In the next, second process, the work vehicle 10 automatically travels along the measurement route R2 from point A to point B. At this time, the work vehicle 10 is traveling in the approach section R22 set on the point A side, so sampling of the output of the measuring device 14 has not yet been performed. Then, while traveling in the approach section R22, the work vehicle 10 is accurately aligned with the measurement route R2. In this second process, it is preferable to display guidance to the operator on the display unit 31 of the terminal device 3, such as "This is the approach section (5 m)."

[0093] In the next, third process, the work vehicle 10 automatically travels from point A to point B along travel section R21 of the measurement route R2. At this time, sampling of the output of the measuring device 14 is performed. That is, the acquisition processing unit 24 acquires the output of the measuring device 14 multiple times, and the calculation processing unit 25 calculates the average value of these multiple outputs as the first measurement value. When the work vehicle 10 reaches the end point of the travel section R21 (i.e., the approach section R23), sampling of the output of the measuring device 14 stops. In this third process, it is preferable to display guidance to the operator on the display unit 31 of the terminal device 3, such as, for example, "Measuring roll angle (outbound) (15 m)" or "Measurement of roll angle (outbound) has been completed. Please turn the vehicle body to align it with the start position for the return journey."

[0094] In the next, fourth step, the operator manually drives the work vehicle 10 to the point B side of the measurement route R2. At this time, the operator turns the work vehicle 10 and reverses the direction of the work vehicle 10 so that the work vehicle 10 can travel toward point A. Then, with the work vehicle 10 on the measurement route R2 near point B, automatic driving is started. In this fourth step, it is preferable to display guidance to the operator on the display unit 31 of the terminal device 3, such as "Please start automatic driving (return trip)."

[0095] Thereafter, as on the outbound journey, the work vehicle 10 travels through the approach section R23 and the travel section R21 in that order, and while traveling back through the travel section R21, the output of the measuring device 14 is obtained multiple times, and the average value of these multiple outputs is calculated as the second measurement value.

[0096] When the work vehicle 10 reaches point A, the first measurement value and the second measurement value are used to perform a correction (roll angle correction) based on the deviation of the tilt angle of the work vehicle 10 from the normal value. At this time, it is preferable to display guidance to the operator such as "Measurement of roll angle (return trip) completed," "Do you want to perform roll angle correction? Yes / No," and "Roll angle correction completed."

[0097] FIG. 7 is a graph showing an example of the inclination angles measured by the measurement device 14 when traveling back and forth along the measurement route R2. As shown in FIG. 7, the inclination angle G1 during traveling on the outbound path and the inclination angle G2 during traveling on the return path are basically opposite in sign. In the example of FIG. 7, the average value (first measurement value) of the inclination angle G1 on the outbound path is "-2.10," and the average value (second measurement value) of the inclination angle G2 on the return path is "0.83." Therefore, as shown in FIG. 7, the median value G3 of these inclination angles G1 and G2 is slightly biased toward the negative side, and the average value G4 is "-0.63." In this case, the average value G4 is stored in the memory unit 23 as a correction value.

[0098] As described above, in this embodiment, the first measurement period and the second measurement period are periods during which the work vehicle 10 travels on the same measurement route R2. This makes it easier to align conditions between the first measurement period and the second measurement period, and the deviation of the tilt angle of the work vehicle 10 from the normal value can be determined with high accuracy.

[0099] Furthermore, the first measurement period is a period during outbound travel, and the second measurement period is a period during inbound travel. In other words, the first measurement period and the second measurement period are periods during which the work vehicle 10 travels in opposite directions on the measurement route R2. This makes it easier to align conditions between the first measurement period and the second measurement period, and the deviation of the tilt angle of the work vehicle 10 from the normal value can be determined with high accuracy.

[0100] Furthermore, the first measurement period and the second measurement period are periods during which the work vehicle 10 travels a travel section R21 of the same length on the measurement route R2. In other words, if the length of the travel section R21 is 15 m, then the first measurement period and the second measurement period are periods during which the work vehicle 10 travels the same 15 m. This makes it easier to align the conditions for the first measurement period and the second measurement period, and the deviation of the inclination angle of the work vehicle 10 from the normal value can be determined with high accuracy.

[0101] Furthermore, the first measurement period and the second measurement period are periods during which the vehicle travels the same travel section R21 on the measurement route R2. In other words, the work vehicle 10 travels the exact same section during the first measurement period and the second measurement period. This makes it easier to align conditions between the first measurement period and the second measurement period, and the deviation of the tilt angle of the work vehicle 10 from the normal value can be determined with high accuracy.

[0102] Furthermore, the control method according to this embodiment further comprises aligning the work vehicle 10 with respect to the measurement path R2 while the work vehicle 10 travels through approach sections R22, R23 set before the travel section on the measurement path R2. This reduces the operator's effort in aligning the work vehicle 10 with the measurement path R2, as such precision is not required when positioning the work vehicle 10 near point A or point B on the measurement path R2.

[0103] 8 is a flowchart showing an example of processing related to the tilt angle deviation calculation process. In the control method according to this embodiment, the processing shown in FIG. 8 is performed each time the tilt angle deviation calculation mode is started.

[0104] First, the operator generates a measurement route R2 in the target area F1 by registering points A and B (S1). The operator manually drives the work vehicle 10 to the vicinity of point A.

[0105] Next, the travel control unit 21 starts the automatic travel (outbound) of the work vehicle 10 along the measurement route R2 from point A to point B (S2). Here, the calculation processing unit 25 determines whether the work vehicle 10 is traveling in the travel section R21 (S3), and if it is traveling in the travel section R21 (S3: Yes), samples the inclination angle using the measuring device 14 (S4). On the other hand, when the work vehicle 10 leaves the travel section R21 and reaches the approach section R23 (S3: No), the calculation processing unit 25 averages the multiple inclination angles sampled during the outbound travel in the travel section R21 to calculate a first measurement value (S5).

[0106] Next, the operator manually drives the work vehicle 10 to the vicinity of point B. The driving control unit 21 starts automatic driving (returning) of the work vehicle 10 along the measurement route R2 from point B toward point A (S6). Here, the calculation processing unit 25 determines whether the work vehicle 10 is traveling through travel section R21 (S7), and if it is traveling through travel section R21 (S7: Yes), samples the inclination angle using the measuring device 14 (S8). On the other hand, when the work vehicle 10 leaves travel section R21 and reaches the approach section R22 (S7: No), the calculation processing unit 25 averages the multiple inclination angles sampled during the return travel through travel section R21 to calculate a second measurement value (S9).

[0107] Thereafter, the calculation processing unit 25 compares the first measurement value with the second measurement value to determine the deviation of the tilt angle of the work vehicle 10 from the normal value (S10), and stores the deviation amount in the memory unit 23 as a correction value (S11).

[0108] However, the flowchart shown in FIG. 8 is merely an example, and processes may be added or omitted as appropriate, and the order of processes may be changed as appropriate.

[0109] [5] Variation Below, we will list some modified examples of embodiment 1. The modified examples explained below can be applied in appropriate combinations.

[0110] The control system 1 in the present disclosure includes a computer system. The computer system is primarily composed of one or more processors and one or more memories as hardware. The functions of the control system 1 in the present disclosure are realized by the processor executing a program (a control program for a work vehicle) recorded in the memory of the computer system. The program may be pre-recorded in the memory of the computer system, provided via a telecommunications line, or provided by being recorded on a non-transitory recording medium such as a memory card, optical disk, or hard disk drive that is readable by the computer system. In addition, some or all of the functional units included in the control system 1 may be configured with electronic circuits.

[0111] Furthermore, it is not essential for the control system 1 that at least some of the functions of the control system 1 are concentrated in one housing, and the components of the control system 1 may be distributed across multiple devices (for example, the control device 2 and the terminal device 3). Conversely, in embodiment 1, the functions distributed across multiple devices may be concentrated in one housing. Furthermore, at least some of the functions of the control system 1 may be realized by the cloud (cloud computing) or the like.

[0112] Furthermore, the terminal device 3 is not limited to a general-purpose terminal such as a tablet terminal, smartphone, or laptop computer, but may be configured as a dedicated terminal. Furthermore, multiple terminal devices 3 may be associated with one work vehicle 10, in which case one work vehicle 10 can be controlled by multiple terminal devices 3. Conversely, one terminal device 3 may be associated with multiple work vehicles 10, in which case multiple work vehicles 10 can be controlled by one terminal device 3.

[0113] In addition, in the first embodiment, the steered wheels 111 are a pair of left and right front wheels, but this is not limited thereto. For example, in addition to or instead of the pair of left and right front wheels, a pair of left and right rear wheels may constitute the steered wheels. In this case, the rear wheels as the steered wheels are also steered. Furthermore, the drive wheels 112 are not limited to a pair of left and right rear wheels, and for example, in addition to or instead of the pair of left and right rear wheels, a pair of left and right front wheels may constitute the drive wheels. Furthermore, the steered wheels 111 may be a single wheel or three or more wheels. Similarly, the drive wheels 112 may be a single wheel or three or more wheels. The same wheel may be used as both the steered wheels 111 and the drive wheels 112.

[0114] Furthermore, it is not essential that the arithmetic processing unit 25 automatically stores the calculated deviation amount as a correction value in the memory unit 23 and automatically corrects the output of the measuring device 14. For example, the deviation amount of the tilt angle calculated by the arithmetic processing unit 25 from the normal value may be displayed on the display unit 31 of the terminal device 3, and an operator who sees the deviation amount may manually input the correction value on a setting screen.

[0115] Furthermore, in the first embodiment, an example was shown in which the average value of the inclination angle on the outbound journey (first measurement value) and the average value of the inclination angle on the return journey (second measurement value) were calculated and these first and second measurement values ​​were compared, but this is not the only example. For example, all inclination angles on the outbound journey and the return journey may be sampled, and the average value of the inclination angle over the entire outbound journey may be calculated. This case is also equivalent to taking the average (median) of the first and second measurement values.

[0116] Furthermore, the work vehicle 10 is not limited to a configuration having a cabin as the driver's section 113, and may be, for example, a ROPs specification having a ROPs frame that protects the operator in the event of a rollover of the work vehicle 10. In this case, the antenna unit 20 is attached to, for example, the ROPs frame.

[0117] Furthermore, it is not essential that the measurement device 14 and the positioning device 15 are integrated to form the antenna unit 20, and the measurement device 14 and the positioning device 15 may be provided separately.

[0118] [Appendix to the invention] The following is a summary of the invention extracted from the above-described embodiment. Note that the configurations and processing functions described in the following supplementary notes can be selected and combined as desired.

[0119] <Appendix 1> acquiring a first measurement value relating to the tilt angle of the work vehicle in a first measurement period and a second measurement value relating to the tilt angle of the work vehicle in a second measurement period based on an output of a measurement device mounted on the work vehicle and measuring the tilt angle of the work vehicle relative to a reference attitude; and determining a deviation of the tilt angle of the work vehicle from a normal value based on a comparison result between the first measurement value and the second measurement value. A method for controlling a work vehicle.

[0120] <Appendix 2> The first measurement period and the second measurement period are periods during which the work vehicle travels on the same measurement route. A control method for a work vehicle according to claim 1.

[0121] <Appendix 3> The first measurement period and the second measurement period are periods during which the work vehicle travels in opposite directions on the measurement route. A control method for a work vehicle according to claim 2.

[0122] <Appendix 4> The first measurement period and the second measurement period are periods during which the work vehicle travels along a travel section of the same length on the measurement route. 4. A control method for a work vehicle according to claim 2 or 3.

[0123] <Appendix 5> The first measurement period and the second measurement period are periods during which the vehicle travels along the same travel section on the measurement route. A method for controlling a work vehicle according to claim 4.

[0124] <Appendix 6> The method further includes aligning the work vehicle with respect to the measurement route while the work vehicle travels through a run-up section set before the travel section on the measurement route. A method for controlling a work vehicle according to claim 5.

[0125] <Appendix 7> the first measurement value is an average value of the tilt angle of the work vehicle during the first measurement period, The second measurement value is an average value of the tilt angle of the work vehicle during the second measurement period. 7. A control method for a work vehicle according to claim 1.

[0126] <Appendix 8> The tilt angle of the work vehicle is corrected based on a deviation of the tilt angle from the normal value. 8. A control method for a work vehicle according to claim 1.

[0127] <Appendix 9> The inclination angle is an angle of inclination in a roll angle direction of the work vehicle. 9. A control method for a work vehicle according to claim 1.

[0128] <Appendix 10> A method for controlling a work vehicle according to any one of claims 1 to 9, A control program for a work vehicle to be executed by one or more processors. [Explanation of symbols]

[0129] 1. Control system for work vehicles 10 Work vehicles 11 aircraft 14 Measuring equipment 24 Acquisition processing unit 25 Processing unit 100 Work Systems R2 measurement path R21 driving section R22, R23 approach section

Claims

1. acquiring a first measurement value relating to the tilt angle of the work vehicle in a first measurement period and a second measurement value relating to the tilt angle of the work vehicle in a second measurement period based on an output of a measurement device mounted on the work vehicle and measuring the tilt angle of the work vehicle relative to a reference attitude; and determining a deviation of the tilt angle of the work vehicle from a normal value based on a comparison result between the first measurement value and the second measurement value. A method for controlling a work vehicle.

2. The first measurement period and the second measurement period are periods during which the work vehicle travels on the same measurement route. A method for controlling a work vehicle according to claim 1.

3. The first measurement period and the second measurement period are periods during which the work vehicle travels in opposite directions on the measurement route. The method for controlling a work vehicle according to claim 2.

4. The first measurement period and the second measurement period are periods during which the work vehicle travels along a travel section of the same length on the measurement route. A method for controlling a work vehicle according to claim 2 or 3.

5. The first measurement period and the second measurement period are periods during which a vehicle travels along the same travel section on the measurement route. The method for controlling a work vehicle according to claim 4.

6. The method further includes aligning the work vehicle with respect to the measurement route while the work vehicle travels through a run-up section set before the travel section on the measurement route. The method for controlling a work vehicle according to claim 5.

7. the first measurement value is an average value of the tilt angle of the work vehicle during the first measurement period, the second measurement value is an average value of the tilt angle of the work vehicle during the second measurement period; A method for controlling a work vehicle according to any one of claims 1 to 3.

8. The tilt angle of the work vehicle is corrected based on a deviation of the tilt angle from the normal value. A method for controlling a work vehicle according to any one of claims 1 to 3.

9. The inclination angle is an angle of inclination in a roll angle direction of the work vehicle. A method for controlling a work vehicle according to any one of claims 1 to 3.

10. A method for controlling a work vehicle according to any one of claims 1 to 3, A control program for a work vehicle to be executed by one or more processors.

11. an acquisition processing unit that is mounted on the work vehicle and acquires a first measurement value related to the tilt angle of the work vehicle in a first measurement period and a second measurement value related to the tilt angle of the work vehicle in a second measurement period based on the output of a measurement device that measures the tilt angle of the work vehicle relative to a reference attitude; a calculation processing unit that determines a deviation of the tilt angle of the work vehicle from a normal value based on a comparison result between the first measurement value and the second measurement value, Control systems for work vehicles.

12. The work vehicle control system according to claim 11; and an airframe on which the measuring device is mounted. Working system.

Images