JP2023175014A - Work vehicle wireless management system - Google Patents

Abstract

To provide a work vehicle wireless management system that builds a more effective wireless communication network.SOLUTION: A work vehicle wireless management system uses a wireless communication network to manage work travel by work vehicles. A plurality of communication units 4 that handle wireless transmission data regarding work travel of the work vehicles are provided. Each of the communication units 4 uses a frequency band selected for each data type of the wireless transmission data from a plurality of different frequency bands as a frequency band to use, and performs communication processing on the wireless transmission data.SELECTED DRAWING: Figure 1

Description

The present invention relates to a work vehicle wireless management system that manages work travel by a work vehicle using a wireless communication network.

Work vehicles in recent years are equipped with wireless communication devices and can exchange information with external communication devices via wireless communication networks. In particular, a work vehicle that automatically travels receives various control commands related to work travel from other work vehicles or a remote control device brought by a manager, and performs control operations based on the received control commands.

For example, in the work vehicle operation system disclosed in Patent Document 1, the work vehicle is equipped with a control module that outputs a control signal to control operating equipment by operating an operation device, and a mobile information terminal as a remote control device is , a display capable of displaying a pseudo-operation device corresponding to the operating device of the work vehicle, and a remote control unit that generates a remote-control signal based on an operation input to the pseudo-operation device. By operating this pseudo-operation device, the user can remotely control the operation of the work vehicle by giving the same operation commands to the work vehicle as when operating the actual operation device.

Further, Patent Document 2 discloses a work vehicle coordination system in which ground work is performed by a master work vehicle and an unmanned slave work vehicle that follows the master work vehicle. In this system, a manned master work vehicle and an unmanned slave work vehicle that follows the master work vehicle perform ground work by traveling in a straight line back and forth, repeating straight travel and U-turns. At that time, the work travel target position data of the child work vehicle is calculated by taking into consideration the parent travel trajectory data, parent ground working width data, and child ground work width data calculated from the parent position data indicating the position of the parent work vehicle. be done. The calculated work travel target position data is wirelessly transmitted to the child work vehicle. The received work travel target position data becomes the steering control target value, and the slave work vehicle is operated unmanned.

Japanese Patent Application Publication No. 2014-192740 Japanese Patent Application Publication No. 2014-178759

In the system disclosed in Patent Document 1, by constructing a wireless communication network between the working vehicle and the remote control device, the traveling work of the working vehicle can be remotely controlled by the remote control device. Furthermore, in the system disclosed in Patent Document 2, a wireless communication network is constructed between a manned work vehicle and an unmanned work vehicle to exchange data regarding each other's work travel and perform cooperative travel work. The types and amounts of data exchanged between work vehicles and remote control devices and between manned work vehicles and unmanned work vehicles are increasing year by year. In addition, the types of data to be communicated include those for which communication errors cannot be tolerated, such as emergency stop commands, and those for which the amount of data is large, such as surrounding photographic images, even if a communication error would not be fatal. It's mixed. Under these circumstances, there is a demand for a work vehicle wireless management system that establishes a more effective wireless communication network between a plurality of work vehicles.

The present invention provides a work vehicle wireless management system for managing work travel by a work vehicle using a wireless communication network, comprising a plurality of communication units handling wireless transmission data regarding work travel of the work vehicle, and The communication unit performs communication processing on the wireless transmission data using a frequency band selected for each data type of the wireless transmission data from a plurality of different frequency bands as a frequency band to be used.

In this configuration, for the wireless transmission data regarding the work travel of the plurality of work vehicles, a frequency band selected for each data type of the wireless transmission data from a plurality of different frequency bands is used as the frequency band to be used. Therefore, an appropriate frequency band can be used for wireless data transmission depending on the data type. In addition, by using multiple frequency bands, communication of wirelessly transmitted data becomes multi-channel, so there is the advantage that the amount of wirelessly transmitted data required for work driving of a work vehicle can be appropriately distributed. .

In one preferred embodiment of the present invention, there is provided a communication state determination unit that determines the communication state of the plurality of different frequency bands, and a communication state determination unit that selects the frequency band to be used to be allocated to each data type based on the communication state. A frequency band selection section is provided. With this configuration, since the communication status of each of the plurality of frequency bands used as the operating frequency band is checked, it is possible to identify a frequency band in which reception sensitivity has decreased or a frequency band that is experiencing radio wave interference. Therefore, by adjusting the purpose of use of a plurality of frequency bands according to the communication state, it is possible to perform optimal wireless transmission according to the communication state.

In one of the preferred embodiments of the present invention, the plurality of frequency bands include a first frequency band, a second frequency band, and a third frequency band, and the first frequency band is the second frequency band. higher than the frequency band, the second frequency band is higher than the third frequency band, and the data types include photographed image data around the working vehicle, control information data regarding the traveling work of the working vehicle, and an emergency stop command for causing an emergency stop, and if all of the plurality of frequency bands are in good condition, the first frequency band is the used frequency band for the photographed image data. The second frequency band is used as the working frequency band for the control information data, and the third frequency band is used as the working frequency band for transmitting the emergency stop command.

In wireless data transmission, in high frequency bands, the amount of data transmitted increases, but its propagation characteristics worsen, and in low frequency bands, the amount of data transmitted decreases, but its propagation characteristics improve. It has characteristics. Taking this into consideration, in the configuration described above, although the amount of data is large, the loss of the transmitted data is not fatal, and for wireless transmission of photographed image data around the work vehicle, the first Frequency bands are used. Further, although the amount of data is small, the third frequency band, which has the lowest frequency, is used for wireless transmission of an emergency stop command in which loss of transmitted data can be fatal. Furthermore, the second frequency band is used for wireless transmission of control information data where loss of transmitted data is not fatal and the amount of data is not large. As a result, a frequency band that is appropriately selected according to the type of data necessary for the work vehicle to travel is used for data transmission.

In order to ensure that work using multiple work vehicles is performed as desired, it is important for a driver on board a manned work vehicle to monitor the automatic operation of an unmanned work vehicle. Furthermore, the movement of an unmanned work vehicle may fall into the blind spot of the driver of a manned work vehicle, or the driver of a manned work vehicle may miss unexpected movements of the unmanned work vehicle, so measures must be taken to deal with such situations. In order to achieve this, it is also important to have a configuration in which a supervisor who stands at the work site and monitors the movement of the unmanned working vehicle uses a remote control device to bring the unmanned working vehicle to an emergency stop. Therefore, in one of the preferred embodiments of the present invention, the plurality of work vehicles include a manned work vehicle that travels manually and an unmanned work vehicle that travels automatically, and the photographed image data is communicated. The control information data is transmitted between the manned work vehicle and the unmanned work vehicle, and the emergency stop command is transmitted between a remote control device operated by a user outside the work vehicle and the unmanned work vehicle. It is carried out between.

In one of the preferred embodiments of the present invention, when there is a margin of data transmission capacity in at least one of the used frequency bands, at least a part of the data content in at least one of the data types is Redundant transmission is performed using the frequency bands used that have sufficient capacity. In this configuration, if there is free space in the used frequency band allocated according to the data type, that free space is used to wirelessly transmit at least some data of other data types, preferably important data. be done. This improves the communication reliability of wireless transmission.

In one of the preferred embodiments of the present invention, if at least one of the plurality of frequency bands is determined to be defective and at least one is determined to be good, the frequency band determined to be defective is assigned. At least part of the wireless transmission data of the data type transmitted in the used frequency band is transmitted using the used frequency band, which is a frequency band determined to be good. With this configuration, if reception sensitivity is reduced or radio wave interference occurs in a specific frequency band, at least part of the wireless transmission data of the data type that is allocated to the specific frequency band is transferred to the communication state. Since wireless transmission can be carried out by interrupting other used frequency bands with good performance, the minimum communication reliability of wireless transmission is ensured.

If an unmanned work vehicle is connected to a wireless communication network and runs automatically, depending on the conditions of the work site and the type of work, it may be necessary to avoid driving even if part of the wireless communication network is cut off. Therefore, in one of the preferred embodiments of the present invention, if at least one of the plurality of frequency bands is determined to be defective, the unmanned working vehicle is forcibly stopped.

In a preferred embodiment of the present invention, the communication state determination section is configured to determine the communication state based on received signal strength, beacon signal check, or both. A configuration in which the communication state is determined based only on the received signal strength requires simple circuits and programs, and is advantageous in terms of cost. The configuration in which the communication state is determined by checking the beacon signal involves transmission and reception of actual data (beacon signal), so the communication state can be determined more reliably. In a configuration in which the communication state is determined based on both the received signal strength and the beacon signal check, it is easier to investigate the cause of a communication state failure, so more appropriate measures can be taken when a communication state failure occurs.

FIG. 1 is an explanatory diagram illustrating the basic configuration of one embodiment of a work vehicle wireless management system. 1 is a side view of a tractor that is an example of a work machine that employs a work vehicle wireless management system. FIG. 1 is a schematic diagram showing an example of a work vehicle wireless management system including a manned work vehicle, an unmanned work vehicle, and a remote control device. FIG. 3 is a plan view of the remote control device. FIG. 2 is a functional block diagram showing functional parts of the unmanned working vehicle. 2 is a flowchart illustrating an example of a wireless data transmission management routine in the work vehicle wireless management system. 2 is a flowchart illustrating an example of a wireless data transmission management routine in the work vehicle wireless management system.

Next, one embodiment of the work vehicle wireless management system of the present invention will be described using the drawings. FIG. 1 shows the basic configuration of this work vehicle wireless management system. The wireless communication network of this working vehicle wireless management system includes a communication unit 4 installed in each of the two working vehicles and a remote control device 9 carried by a supervisor. The frequency bands handled by this wireless communication network are a first frequency band, a second frequency band, and a third frequency band. The first frequency band is the highest band, followed by the second frequency band and the third frequency band are the lowest bands. Each frequency band is officially defined, and the first frequency band is the 2.4 giga band, the second frequency band is the 920 mega band, and the third frequency band is the 429 mega band. Of course, other bands may also be used.

The types of wireless transmission data handled by the wireless communication network of this embodiment are photographed image data around the work vehicle, control information data regarding the traveling work of the work vehicle, and emergency stop commands for bringing the work vehicle to an emergency stop. . In principle, the frequency band used for wireless transmission of photographed image data is called the first frequency band, and the frequency band used for wireless transmission of control information data is called the second frequency band. The frequency band used for transmission is called the third used frequency band.

The communication unit 4 includes a communication processing section 40, a communication state determination section 41, and a frequency band selection section 42. The communication processing unit 40 has a function of converting input data into a form that can be wirelessly transmitted, and a function of converting received wireless transmission data into a necessary form and outputting it. The communication state determining unit 41 determines the communication state in the first frequency band, the second frequency band, and the third frequency band. When determining the communication state based on the received signal strength, the strength of the input signal from the antenna 49 is measured. If the measured intensity is greater than or equal to the threshold, it is determined that the communication condition is good, and if the measured intensity is less than the threshold, it is determined that the communication condition is poor. When determining the communication state by checking the beacon signal, each communication unit 4 periodically transmits a beacon signal, and if the reception is successful, it is determined that the communication state is good, and if the reception is unsuccessful, the communication state is determined to be good. is determined to be defective.

The used frequency band selection unit 42 selects a frequency band used for photographed image data (i.e., a first used frequency band), a frequency band used for wireless transmission of control information data (i.e., a second used frequency band), and an emergency stop command. The frequency band used for wireless transmission (that is, the third used frequency band) is selected based on the communication state determined by the communication state determination unit 41.

If the reception conditions for all of the first frequency band, second frequency band, and third frequency band are good, the first frequency band is assigned to the first used frequency band, and the second used frequency band is assigned as the initial setting. is assigned the second frequency band, and the third frequency band is assigned the third frequency band.

If the reception condition of any one of the first frequency band, second frequency band, and third frequency band is poor, the following emergency stop notification process can be arbitrarily adopted.
(1) If the communication condition of the first frequency band is determined to be poor and the communication condition of the second frequency band is determined to be good, the captured image data to which the first frequency band is assigned as the first frequency band , and the control information data are wirelessly transmitted using the second frequency band. In this case, it is preferable that the photographed image data is converted to still image data or the like instead of moving image data to reduce the amount of data. Similarly, if the communication condition of the second frequency band is determined to be poor and the communication condition of the first frequency band is determined to be good, the control information data in which the second frequency band is assigned as the second frequency band to be used is , and the captured image data are wirelessly transmitted using the first frequency band.
(2) If the communication condition of the third frequency band is determined to be poor and the communication condition of the first frequency band or the second frequency band is determined to be good, the third frequency band is assigned as the third frequency band to be used. An emergency stop command is wirelessly transmitted using the first frequency band or the second frequency band as the third frequency band used.
(3) If the communication state of the third frequency band is determined to be poor, a situation may arise in which the emergency stop command cannot be wirelessly transmitted, so the work vehicle is forcibly stopped.
(4) If any one of the first frequency band, second frequency band, and third frequency band is determined to be defective, the work vehicle is forced to stop for the time being.

On the other hand, if at least one of the first frequency band, second frequency band, and third frequency band has sufficient data transmission capacity, the first frequency band or the second frequency band has sufficient data transmission capacity. If there is a surplus in data transmission capacity, control information data or captured image data is redundantly transmitted using a frequency band in which there is a surplus.

Next, as a specific application example of the work vehicle wireless management system shown in FIG. Describes a system that is carried by a user outside of a computer.

FIG. 2 shows a tractor as an example of a work vehicle that participates in this work vehicle wireless management system. This tractor is provided with a steering section 20 in the center of a vehicle body 1 supported by front wheels 11 and rear wheels 12. A working device 30, which is a rotary tiller, is installed at the rear of the vehicle body 1 via a hydraulic lifting mechanism 31. The front wheels 11 function as steering wheels, and the driving direction of the tractor is changed by changing the steering angle by the steering mechanism 13. The steering angle of the front wheels 11 is changed by the operation of the steering mechanism 13. The steering mechanism 13 includes a steering motor 14 for automatic steering. During manual driving, the front wheels 11 can be steered by operating a steering wheel 22 disposed on the control section 20. A general-purpose terminal 3 equipped with a display, a speaker, a touch panel, and operation buttons is arranged in the control section 20. This general-purpose terminal 3 has a function of providing information to the driver and a function of inputting information from the driver.

The tractor cabin 21 is provided with a satellite positioning module 80 configured as a GNSS (global navigation satellite system) module. As a component of the satellite positioning module 80, a satellite antenna for receiving GNSS signals (including GPS signals) is attached to the ceiling area of the cabin 21. Note that in order to supplement satellite navigation, it is possible to combine the satellite positioning module 80 with an inertial navigation module incorporating a gyro acceleration sensor and a magnetic azimuth sensor. The inertial navigation module may be located at a separate location from the satellite positioning module 80. The vehicle body 1 is further equipped with a plurality of photographing cameras 85 that take pictures of the surroundings during traveling work, and an obstacle sensor 86 that detects surrounding obstacles.

FIG. 3 shows how a field is cultivated by a manned work vehicle that is driven by a driver (user) and an unmanned work vehicle that is driven unmanned. Here, the manned work vehicle and the unmanned work vehicle are tractors of substantially the same type, and are equipped with the communication unit 4 shown in FIG. 1. A farm field is divided into a substantially rectangular central area and a peripheral area, also called headland, defined along the ridges around the central area. In the central region, ground work is performed by reciprocating travel, so the travel trajectory is a repetition of straight forward travel, turning (U-turn) travel, straight homeward travel, and turning (U-turn) travel. The headland serves as a turning area during work travel in the central work area. In the peripheral area, circular work driving is performed by repeatedly driving in a straight line and turning around at each corner area. Two-way wireless communication is performed between the manned work vehicle and the unmanned work vehicle. Furthermore, a supervisor (user) with a remote control device 9 is standing on the ridge. The remote control device 9 performs unidirectional wireless communication with the unmanned work vehicle.

A plan view of the remote control device 9 is shown in FIG. This remote control device 9 is a handy type that can be operated with one hand. A power button, an emergency stop button 91, an automatic travel start button 92, and a temporary stop button 93 are provided on its surface. When the emergency stop button 91 is pressed, an emergency stop command is transmitted to the communication unit 4 of the unmanned work vehicle. Similarly, if the automatic travel start button 92 is pressed, an automatic travel start command is transmitted, and if the pause button 93 is pressed, a temporary stop command is transmitted.

In this wireless communication network, wireless communication is performed between the manned work vehicle and the unmanned work vehicle using two channels, a first frequency band and a second frequency band. The first used frequency band is used for transmitting photographed image data by the photographing camera 95. The second used frequency band is used for exchanging control information data generated in each of the manned work vehicle and the unmanned work vehicle. The control information data includes the state of the vehicle body 1 of each work vehicle (vehicle position, engine speed, vehicle speed, etc.), the state of the work device 30 (work depth, posture, etc.), detection results of the obstacle sensor 86, etc. It will be done.

FIG. 5 shows a functional block diagram of the control system of the unmanned working vehicle. Since the control systems of manned work vehicles are also substantially the same, the explanation of the control system of unmanned work vehicles can be applied to the description of the control system of manned work vehicles.

The control unit CU, which is a core element of the control system of the unmanned working vehicle, includes an output processing section 7 and an input processing section 8 as input/output interfaces. For wireless data exchange with the outside, the communication unit 4 described in FIG. 1 is installed, and this communication unit 4 is connected to the control unit CU through the on-vehicle LAN. Of course, the communication unit 4 may also be constructed within the control unit CU. A general-purpose terminal 3 equipped with a graphic user interface is also connected so that the movement of the work vehicle can be managed by user operations. In FIG. 5, the general-purpose terminal 3 is a fixed type connected to the in-vehicle LAN, but if it is configured to be able to wirelessly exchange data with the control unit CU via the communication unit 4, it can be taken out of the vehicle. , can be used.

The output processing unit 7 is connected to a work traveling equipment group 70 consisting of a vehicle traveling equipment group 71 and a working equipment equipment group 72, and a notification device 73 consisting of a lamp, a buzzer, a speaker, etc. The vehicle running equipment group 71 includes control equipment related to vehicle running, such as an engine control equipment, a shift control equipment, a braking control equipment, a steering control equipment, and the like. The working device equipment group 72 includes power control devices such as a PTO clutch of the working device 30, which is a rotary tilling device in this embodiment, and lifting cylinder control devices of the lifting mechanism 31 that raises and lowers the rotary tilling device. .

Connected to the input processing unit 8 are a satellite positioning module 80, an automatic/manual switching operation tool 81, a driving state detection sensor group 82, a work state detection sensor group 83, a photographing camera 85, an obstacle sensor 86, and the like. The automatic/manual switching operation tool 81 is a switch that selects either an automatic driving mode in which the vehicle travels with automatic steering or a manual steering mode in which the vehicle travels with manual steering. For example, by operating the automatic/manual switching operation tool 81 while driving in automatic steering mode, driving can be switched to manual steering, and by operating the automatic/manual switching operation tool 81 while driving in manual steering mode. , the vehicle can be switched to automatic steering. The running state detection sensor group 82 includes sensors that detect the states of operating tools (components of the work running operating tool group 84) such as an engine speed adjuster, an accelerator pedal, a brake pedal, and the steering wheel 22. . The work state detection sensor group 83 includes sensors that detect the state of work operating tools (components of the work travel operating tool group 84) that adjust the drive and posture of the work device 30.

The control unit CU incorporates a working travel control section 50, an automatic travel control section AC, a transmission data processing section 61, and a mode switching section 62 as functional sections that are substantially constructed by software.

The work travel control section 50 includes a travel control section 51, a work control section 52, and an engine control section 53. The running control unit 51 controls the vehicle running equipment group 71. Since this tractor is configured to be able to travel in both automatic travel (automatic steering) and manual travel (manual steering), travel control section 51 has a manual travel control function and an automatic travel control function. When the manual travel control function is being executed, the vehicle travel equipment group 71 is controlled based on the operation by the driver. When the automatic cruise control function is being executed, a steering control signal (a type of operation control signal) generated based on an automatic steering command given from the automatic cruise control unit AC is output to the steering motor 14. The work control unit 52 provides a work control signal (a type of operation control signal) to the work equipment equipment group 72 in order to control the movement of the work equipment 30. The engine control unit 53 provides an engine control signal (a type of operation control signal) to the operating equipment of the engine.

The automatic travel control unit AC includes a route generation unit 54, a route setting unit 55, an own vehicle position calculation unit 56, and an automatic work travel command unit 57.

The route generation unit 54 reads out the external shape data of the field from the inputted field information, and generates an appropriate travel route in this field. This driving route may be generated automatically based on basic initial parameters input by the driver, or a driving route generated by another computer may be downloaded. In any case, the travel route output from the route generation unit 54 is developed in memory and used for automatic travel. Of course, this traveling route can be used for guidance for the work vehicle to travel along the traveling route even when traveling manually.

The route setting unit 55 sequentially reads out the travel routes developed in the memory and sets them as the target travel route. The own vehicle position calculation unit 56 calculates the position of the vehicle body 1 or the position of the working device 30 based on positioning data sequentially sent from the satellite positioning module 80. The automatic work travel command unit 57 calculates the azimuth deviation and positional deviation between the target travel route and the own vehicle position, and provides the travel control unit 51 with an automatic steering command to eliminate the azimuth deviation and positional deviation.

The mode switching unit 62 has a function of switching between a manned work vehicle mode in which the work vehicle functions as a manned work vehicle and an unmanned work vehicle mode in which the work vehicle functions as an unmanned work vehicle when a plurality of work vehicles perform work in cooperation through a user operation. have The transmission data processing unit 61 handles control information data indicating the work running state detected by the running state detection sensor group 82, the work state detection sensor group 83, and the obstacle sensor 86, and the photographed image data from the photographing camera 85. The transmission data processing unit 61 converts various data into a suitable format for converting it into wireless transmission data, and converts the wireless transmission data sent into a data format that can be internally processed.

Next, an example of a wireless data transmission management routine in an unmanned work vehicle will be explained using FIGS. 6 and 7.
First, the determination result from the communication state determining unit 41 is taken in, and it is checked whether the third frequency band communication state is good (#01). In the default state, this third frequency band is used as the third used frequency band for transmitting an emergency stop command from the remote control device 9. Therefore, if the communication state of the third frequency band is poor (No branch in #01), the transmission data processing unit 61 issues an automatic travel stop command to the work travel control unit 50 (#61). As a result, the unmanned work vehicle stops automatically driving. Further, a stop notification process (driving a lamp or a buzzer) indicating the stop of automatic driving is executed (#62).

If the communication state of the third frequency band is good (Yes branch in #01), it is further checked whether the communication states of the first frequency band and the second frequency band are good (#02). In this check, different processes are performed depending on the following four communication states.

(1) When the communication conditions of the first frequency band and the second frequency band are good (#10):
The first frequency band is used as the first used frequency band (#11). The second frequency band is used as a second used frequency band (#12).

(2) When the communication condition is good only in the first frequency band (#20):
The first frequency band is used as the first used frequency band (#21). Therefore, the photographed image data is wirelessly transmitted using the first frequency band, which is the 2.4 giga band. Furthermore, it is checked whether there is enough margin for data transmission in the first used frequency band, which is the first frequency band (#22). If there is a margin for data transmission in the first used frequency band (Yes branch in #22), the control information data that was originally intended to be transmitted in the second frequency band is transferred to the margin in the first used frequency band (first frequency band). put on. Therefore, the control information data is simplified (data amount reduced) to the necessary extent (#23). The control information data is then transmitted using the first frequency band. In other words, the first frequency band is also used as the second frequency band (#24). If there is no margin for data transmission in the first used frequency band (No branch in #22), the first frequency band is used as the first used frequency band and the second used frequency band, and the captured image data and control information data are used for both wireless transmission. Therefore, the photographed image data is simplified (data amount reduced) to the necessary extent by frame thinning, still image conversion, etc. (#25). Similarly, the control information data is also simplified (data amount reduced) to a necessary extent (#26). Then, the photographed image data and the control information data are transmitted using the first frequency band. That is, the first frequency band is used not only as the first used frequency band but also as the second used frequency band (#27).

(3) When the communication status of the first frequency band and the second frequency band is poor (#30):
It is checked whether there is enough margin for data transmission in the third used frequency band, which is the third frequency band (#31). If there is a margin for data transmission in the third used frequency band (Yes branch in #31), the captured image data that was originally intended to be transmitted in the first frequency band is transferred to the margin in the third used frequency band (third frequency band). and control information data that was originally intended to be transmitted in the second frequency band. Since the amount of data transmitted in the third frequency band, which is the 429 megaband, is small, the captured image data is simplified to the extent necessary (#34), and the third frequency band is also used as the first frequency band. The simplified photographic image data is wirelessly transmitted in the third frequency band (#35). Similarly, the control information data is simplified to the extent necessary (#36), the third frequency band is also used as the second frequency band, and the simplified control information data is wirelessly transmitted in the third frequency band. (#37). If there is a margin for data transmission in the third used frequency band (No branch in #31), the transmission data processing unit 61 issues an automatic travel stop command to the work travel control unit 50 (#32). As a result, the unmanned work vehicle stops automatically driving. Further, a stop notification process (driving a lamp or a buzzer) indicating the stop of automatic driving is executed (#33).

(4) When the communication condition is good only in the second frequency band (#40):
The second frequency band is used as a second used frequency band (#41). Therefore, the control information data is wirelessly transmitted using the second frequency band, which is the 920 megaband. Furthermore, it is checked whether there is enough margin for data transmission in the second used frequency band, which is the second frequency band (#42). If there is a margin for data transmission in the second used frequency band (Yes branch in #42), the captured image data that was originally intended to be transmitted in the first frequency band is transferred to the margin in the second used frequency band (second frequency band). put on. Therefore, the captured image data is simplified (data amount reduced) to the necessary extent (#43). The captured image data is then transmitted using the second frequency band. In other words, the second frequency band is also used as the first frequency band (#44). If there is not enough room for data transmission in the second used frequency band (No branch in #42), wireless transmission of the photographed image data is stopped (#45), and a notification that the transmission of the photographed image data has been stopped is notified (#46).

[Another embodiment]
(1) In the embodiment described above, three frequency bands were used, but it is also possible to use more frequency bands.
(2) In the embodiment described above, the remote control device 9 was used as a simple signal transmitter that performs unidirectional wireless communication, but instead, a high-performance communication terminal such as a tablet computer can be It may also be used as the device 9. In this case, bidirectional wireless communication is also possible between the remote control device 9 and the work vehicle, and, for example, photographed image data can be displayed on a touch panel of a communication terminal serving as the remote control device 9.
(3) Each functional unit in the functional block diagram shown in FIG. 5 is divided mainly for the purpose of explanation. In practice, each function can be integrated with other functions or divided into multiple functions. For example, the automatic travel control unit AC may be constructed in the general-purpose terminal 3.
(4) In the embodiment described above, the manned work vehicle and the unmanned work vehicle are of the same type and their control systems are also substantially the same, but the manned work vehicle and the unmanned work vehicle may be configured with different types of work vehicles. Good too. Furthermore, the control system may also include only essential parts for each of the manned work vehicle and the unmanned work vehicle.
(5) In the embodiment described above, a tractor equipped with a rotary tiller as the working device 30 was used as a working vehicle, but other than such a tractor, for example, a rice transplanter, a fertilizer spreader, a combine harvester, etc. Various work vehicles such as agricultural work vehicles such as , construction work vehicles equipped with dozers, rollers, etc. as the work equipment 30 can also be adopted as embodiments. Further, one of the work vehicles may be a vehicle that does not actually perform work.

INDUSTRIAL APPLICABILITY The present invention is applicable to a work vehicle wireless management system that manages work travel by a work vehicle using a wireless communication network.

3: General-purpose terminal 4: Communication unit 40: Communication processing unit 41: Communication status determination unit 42: Frequency band selection unit 50: Work travel control unit 61: Transmission data processing unit 62: Mode switching unit 85: Photographing camera 86: Failure Object sensor 9: Remote control device 91: Emergency stop button 92: Automatic travel start button 93: Pause button 95: Photographing camera AC: Automatic travel control unit CU: Control unit

Claims (7)

A work vehicle wireless management system that manages work travel by a work vehicle using a wireless communication network,
A plurality of communication units are provided that handle wirelessly transmitted data regarding work travel of the work vehicle, and
The communication unit performs communication processing on the wireless transmission data using a frequency band selected for each data type of the wireless transmission data from a plurality of different frequency bands as a frequency band to be used,
The plurality of frequency bands include a first frequency band and a third frequency band, the first frequency band being higher than the third frequency band,
The data types include photographed image data around the work vehicle, control information data regarding the traveling work of the work vehicle, and an emergency stop command for bringing the work vehicle to an emergency stop, and
When all of the plurality of frequency bands are in good condition, the first frequency band is used as the used frequency band for the captured image data, and the third frequency band is used for transmitting the emergency stop command. used as the frequency band used in
A work vehicle wireless management system in which automatic driving of the work vehicle is forcibly stopped when the third frequency band is determined to be defective, even if the first frequency band is in a good state. a communication state determination unit that determines communication states of the plurality of different frequency bands;
The work vehicle wireless management system according to claim 1, further comprising: a frequency band selection unit that selects the frequency band to be used to be allocated to each data type based on the communication state. The work vehicle wireless management system according to claim 2, wherein the communication state determination unit determines the communication state based on received signal strength, beacon signal check, or both. A plurality of the work vehicles including a manned work vehicle that travels manually and an unmanned work vehicle that travels automatically are provided,
Communication of the photographed image data and transmission of the control information data are performed between the manned work vehicle and the unmanned work vehicle,
The work vehicle wireless management system according to any one of claims 1 to 3, wherein the transmission of the emergency stop command is performed between the remote control device operated by a user outside the work vehicle and the unmanned work vehicle. . If there is a surplus in data transmission capacity in at least one of the used frequency bands, at least a part of the data content in at least one of the data types is transmitted using the used frequency band in which there is a surplus in the data transmission capacity. The work vehicle wireless management system according to any one of claims 1 to 4, wherein the work vehicle wireless management system is transmitted in duplicate. If at least one of the plurality of frequency bands is determined to be defective and at least one is determined to be good, the type of data transmitted in the used frequency band to which the frequency band determined to be defective is allocated. The work vehicle wireless management system according to any one of claims 1 to 5, wherein at least a part of the wireless transmission data is transmitted using the used frequency band, which is a frequency band determined to be good. The work vehicle wireless management system according to any one of claims 1 to 6, wherein the work vehicle is forcibly stopped when at least one of the plurality of frequency bands is determined to be defective.

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