Remote control system for work equipment

Abstract

The present invention hedges a risk for a communication delay that may occur at the time of remote control of a work machine (1).　A remote control system (100) for a work machine comprises: a monitoring device (25) that outputs monitoring data obtained by monitoring the surroundings of a movable work machine; a first assignment unit (21d) that assigns a first timestamp to the monitoring data; a storage device (42, 22) that stores a plurality of sets of monitoring data and first timestamps; a remote control terminal (30) that receives the monitoring data to display a monitoring result and is operated to transmit a remote operation signal; a second assignment unit (31d) that assigns a second timestamp to the remote operation signal; a signal reception unit (41a, 21a) that receives the remote operation signal, determines validity of the remote operation signal on the basis of the second timestamp of the remote operation signal and the first timestamp of the monitoring data stored in the storage device, and invalidates an inappropriate remote operation signal; and a control device (21) that controls the operation of the work machine on the basis of the remote operation signal determined to be appropriate.

Description

[Technical Field]

[0001] The present invention relates to a remote control system for a work machine that remotely controls a travellable work machine. [Background technology]

[0002] A known example of a remote control system for a work machine is the system disclosed in Patent Document 1. The remote control system for a work machine in Patent Document 1 includes an autonomous work machine (work vehicle), a vehicle control device mounted on the work machine, and a remote control terminal (remote operation device) capable of remotely operating the work machine. The remote control terminal is operated by a worker and wirelessly transmits remote operation signals indicating the work area in the field and the work content to the vehicle control device. The vehicle control device controls the work machine based on the received remote operation signals, causing the work machine to work or travel in the work area in the field. The surroundings of the work machine are monitored by an obstacle sensor mounted on the work machine and a camera mounted on the work machine or the field. Monitoring data from the obstacle sensor and camera is transmitted to the remote control terminal and displayed on a display mounted on the remote control terminal. The worker can remotely operate the work machine using the remote control terminal while understanding the conditions around the work machine by viewing the display. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication "Patent No. 6384545" Summary of the Invention [Problem to be solved by the invention]

[0004] When remotely controlling a work machine, communication delays can occur, impairing the real-time nature of monitoring data or remote control signals, and the actual conditions around the work machine can change from those monitored by the remote control terminal. In this case, if the vehicle's control device controls the travel or work operation of the work machine based on the remote control signal from the remote control terminal, there is a risk that the operation will be ineffective (meaningless) or that the work machine will collide with an obstacle.

[0005] In view of the above problems, the present invention aims to provide a remote control system for a work machine that can hedge risks even if a communication delay occurs when remotely controlling a work machine. [Means for solving the problem]

[0006] The technical means of the present invention for solving the above technical problems is characterized by the following points. The remote control system for a work machine of the present invention includes a monitoring device that monitors the periphery of a travellable work machine and outputs monitoring data indicative of the monitoring results; a first assigning unit that assigns a first timestamp to the monitoring data; a storage device that can store a plurality of pieces of the monitoring data together with the first timestamp assigned to the monitoring data; a remote control terminal that is capable of receiving the monitoring data and displaying the monitoring results indicated by the monitoring data and that transmits a remote operation signal to remotely operate the work machine when operated; a second assigning unit that assigns a second timestamp to the remote operation signal when the remote control terminal transmits the remote operation signal; and receiving the remote control signal transmitted from and determining whether the remote control signal is appropriate based on the second timestamp added to the received remote control signal and the first timestamp added to the monitoring data stored in the storage device, and invalidating the remote control signal that is determined to be inappropriate. a signal receiving unit; Based on the remote control signal determined to be appropriate by the signal receiving unit, a control device for controlling the operation of the work machine, and the signal receiving unit The specific monitoring data to which the first timestamp indicating a first time that is the same as the second time indicated by the second timestamp assigned to the received remote control signal or a first time that is earlier than the second time and closest to the second time is assigned, and the latest monitoring data are acquired from the storage device, a difference between the specific monitoring data and the latest monitoring data is detected, and if the difference does not exceed a predetermined level, the received remote control signal is determined to be appropriate, the remote control signal is transferred to the control device, and the control device is allowed to control the operation of the work machine based on the remote control signal, and if the difference exceeds a predetermined level, the received remote control signal is determined to be inappropriate, the remote control signal is invalidated, and the control device is prevented from controlling the operation of the work machine based on the remote control signal. .

[0008] The signal receiving unit may obtain from the storage device specific monitoring data to which the first timestamp indicating a first time that is the same as the second time indicated by the second timestamp assigned to the received remote control signal, or a first time that is earlier than the second time and closest to the second time, and the latest monitoring data, detect a difference between the specific monitoring data and the latest monitoring data, and if the difference does not exceed a predetermined level, determine that the received remote control signal is appropriate and transfer the remote control signal to the control device, allowing the control device to control the operation of the work machine based on the remote control signal, and if the difference exceeds a predetermined level, determine that the received remote control signal is inappropriate and invalidate the remote control signal, preventing the control device from controlling the operation of the work machine based on the remote control signal.

[0009] The first timestamp assigner may assign the first timestamp indicating a current time to the monitoring data every time the first assigner acquires the monitoring data from the monitoring device.

[0010] The second assigning unit may assign the second timestamp indicating a current time to the remote control signal when transmitting the remote control signal from the remote control terminal.

[0011] The remote control terminal has a display unit and is capable of obtaining the latest monitoring data from the storage device and displaying the monitoring results indicated by the monitoring data on the display unit, and the second assigning unit may refer to the first timestamp assigned to the monitoring data indicating the monitoring results that were displayed on the display unit when the remote control terminal was operated, and assign the second timestamp indicating a second time that is identical to the first time indicated by the first timestamp to the remote control signal.

[0012] If the signal receiving unit determines that the received remote control signal is appropriate, it may enable the remote control signal by transferring it to the control device, and if it determines that the received remote control signal is inappropriate, it may disable the remote control signal by discarding it without transferring it to the control device.

[0013] The signal receiving unit may notify the remote control terminal that the remote operation signal has been disabled, and the remote control terminal may have a display unit and, upon receiving the notification from the signal receiving unit, display the contents of the notification on the display unit.

[0014] The remote control terminal may have an operation unit operated by an operator, and generate the remote control signal in response to an operation instruction of the work machine input by operating the operation unit, and the signal receiving unit may determine the appropriateness of the remote control signal based on the operation instruction in response to the received remote control signal.

[0015] The remote control terminal has an operation unit operated by an operator, and generates the remote control signal in response to an operation instruction of the work machine input by operating the operation unit, and the signal receiving unit may determine the appropriateness of the remote control signal when the operation instruction in response to the received remote control signal is an operation instruction related to the travel of the work machine or work performed by a work device connected to the work machine.

[0016] The remote control system for the work machine includes a communication device that is provided on the work machine and communicates wirelessly, and an assistance device that is provided outside the work machine and outside the remote control terminal, wherein the remote control terminal has a first communication unit that performs communication, and the assistance device has a second communication unit that communicates with the communication device and the first communication unit, and the monitoring device and the first providing unit are provided on the work machine, the second providing unit is provided on the remote control terminal, and the memory device and the signal receiving unit are provided on the assistance device.

[0017] The remote control system for the work machine includes a communication device that is provided on the work machine and communicates wirelessly, and an assistance device that is provided outside the work machine and outside the remote control terminal, the remote control terminal having a first communication unit that communicates, the assistance device having a second communication unit that communicates with the communication device and the first communication unit, the monitoring device and the first providing unit being provided on the work machine, the second providing unit being provided on the remote control terminal, and the memory device and the signal receiving unit being provided on the work machine or the assistance device.

[0018] The communication device may communicate wirelessly via a mobile phone communication network, a wide area network, or a narrow area network, and the first communication unit and the second communication unit may communicate wirelessly or wired via a mobile phone communication network, a fixed telephone communication network, a wide area network, or a narrow area network.

[0019] The remote control system for the work machine may include a communication device provided on the work machine and communicating wirelessly, the remote control terminal having a first communication unit for communicating, the monitoring device, the first granting unit, the memory device, and the signal receiving unit being provided on the work machine, and the second granting unit being provided on the remote control terminal.

[0020] The communication device may communicate wirelessly via a mobile phone communication network, a wide area network, or a narrow area network, and the first communication unit may communicate wirelessly or wired via a mobile phone communication network, a fixed telephone communication network, a wide area network, or a narrow area network.

[0021] The wide area network may be comprised of the Internet, and the narrow area network may be comprised of a local area network.

[0022] The work machine may be composed of an agricultural machine that performs agricultural work in a field, the monitoring device may be provided on the agricultural machine and have a camera or sensor that detects objects around the agricultural machine, and the monitoring data may include image data of the area around the agricultural machine captured by the camera or detection data showing the detection results of the sensor. [Effects of the Invention]

[0023] According to the present invention, it is possible to provide a remote control system for a work machine that can hedge risks even if a communication delay occurs during remote control of the work machine. [Brief explanation of the drawings]

[0024] [Figure 1A] 1 is a schematic configuration diagram of a remote control system for a work machine according to an embodiment; [Figure 1B] FIG. 1B is a configuration diagram showing some details of each part of FIG. 1A. [Figure 2] FIG. 1B is a side view of the work machine of FIG. 1A. [Figure 3] FIG. 1B is a block diagram showing the electrical configuration of the work machine of FIG. 1A. [Figure 4] 1B is a block diagram showing the electrical configuration of the remote control terminal of FIG. 1A. [Figure 5] FIG. 1B is a block diagram showing the electrical configuration of the support device of FIG. 1A. [Figure 6A] 1B is a diagram showing a remote monitoring operation screen displayed on the remote control terminal of FIG. 1A. FIG. [Figure 6B] FIG. 10 is a diagram showing a remote monitoring operation screen including an invalidation notification. [Figure 7A] 1C is a flowchart showing the operation of the control device, the support device, and the remote control terminal of the work machine of FIG. 1B. [Figure 7B] 7B is a flowchart continuing from FIG. 7A. [Figure 8] 10 is a flowchart showing the operation of a support device according to another embodiment. [Figure 9] FIG. 10 is a configuration diagram of a remote control system for a work machine according to another embodiment. [Figure 10] FIG. 10 is a configuration diagram of a remote control system for a work machine according to another embodiment. [Figure 11] FIG. 10 is a configuration diagram of a remote control system for a work machine according to another embodiment. [Figure 12] FIG. 10 is a configuration diagram of a remote control system for a work machine according to another embodiment. [Figure 13] FIG. 10 is a diagram showing a display unit of a remote control terminal according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, embodiments of the present invention will be described with reference to the drawings. For convenience, the same reference numerals are used to designate the same or corresponding components.

[0026] Fig. 1A is a schematic diagram of a remote control system 100 for a work machine according to one embodiment. Fig. 1B is a diagram showing some details of each part of Fig. 1A.

[0027] 1A and 1B includes a work machine 1, a remote control terminal 30, and a support device 40. The work machine 1 is composed of an agricultural machine that is capable of traveling and performing work autonomously (also called an autonomous agricultural machine). In this embodiment, the work machine 1 is composed of a tractor, which is an example of an agricultural machine that performs agricultural work in a field.

[0028] The remote control terminal 30 is configured as a portable terminal device such as a tablet device or a smartphone, or a stationary terminal device installed in a base station (not shown). In this embodiment, the remote control terminal 30 is configured as a portable terminal device carried and operated by the operator 60. The remote control terminal 30 is a device for remotely controlling (remotely operating and remotely monitoring) the work machine 1.

[0029] The support device 40 is configured from a server or a PC (personal computer), etc. The support device 40 is installed, for example, at a manufacturer or management center of the work machine 1. The support device 40 supports the remote control of the work machine 1 by the remote control terminal 30. The support device 40 also manages various information and data required for the work machine 1 to perform work in a field, etc.

[0030] The work machine 1 can connect to the Internet 50 via a mobile phone communication network 51 or the like using a wireless communication device 23 (FIG. 1B) installed therein. The remote control terminal 30 can connect to the Internet 50 via a mobile phone communication network 51 or the like using a communication unit 33 (FIG. 1B) installed therein. The support device 40 can connect to the Internet 50 via a mobile phone communication network 51 or a fixed telephone communication network 52 or the like using a communication unit 43 (FIG. 1B) installed therein, which will be described later.

[0031] The wireless communication device 23 of the work machine 1 and the communication unit 33 of the remote control terminal 30 can connect to (access) the support device 40 via a mobile phone communication network 51 or a fixed telephone communication network 52 and the Internet 50, etc. The support device 40 communicates with the wireless communication device 23 of the work machine 1 and the communication unit 33 of the remote control terminal 30 via the mobile phone communication network 51 or the fixed telephone communication network 52 and the Internet 50, etc., using the communication unit 43.

[0032] The wireless communication device 23 of the work machine 1, the remote control terminal 30, and the support device 40 may communicate with each other via a wireless or wired LAN, in addition to a mobile phone communication network 51, a fixed telephone communication network 52, and the Internet 50. The Internet 50 is an example of a wide area network using a public communication network. The LAN is an example of a narrow area network using a dedicated communication line.

[0033] Figure 2 is a side view of the work machine 1. The work machine 1 of this embodiment is configured as a tractor as shown in Figure 2. Note that the work machine 1 may also be configured as an agricultural machine other than a tractor, a construction machine, or a work vehicle.

[0034] As shown in Figure 2, the vehicle body 3 of the work machine 1 is provided with a traveling device 7. The traveling devices 7 are provided on both the left and right sides of the vehicle body 3 and support the vehicle body 3 so that it can travel. The traveling devices 7 are wheeled traveling devices having front wheels 7F and rear wheels 7R made up of tires. Alternatively, traveling devices in which the front wheels or rear wheels are made up of crawlers may be used.

[0035] The vehicle body 3 is equipped with a prime mover 4, a transmission 5, and a cabin 9. The prime mover 4 is composed of an engine (diesel engine, gasoline engine) or an electric motor. The transmission 5 performs a gear change operation to vary the propulsive force of the traveling device 7 and to switch the traveling device 7 between forward and reverse.

[0036] The cabin 9 is provided with a driver's seat 10 and a control device 11. The work machine 1 is a tractor that can travel and work unmanned, but an operator seated in the driver's seat 10 can also operate the control device 11 to control the work machine 1. The cabin 9 is a protective device that protects the driver's seat 10 by surrounding it from the front, rear, above, and on the left and right sides. Instead of the cabin 9, a rope that covers at least the top of the driver's seat 10 may be used.

[0037] The direction indicated by arrow A1 in Fig. 2 is the front of the work device (implement, etc.) 2. The direction indicated by arrow A2 is the rear of the work device 2. The direction indicated by arrow Z1 is above the work device 2. The direction indicated by arrow Z2 is below the work device 2. The direction perpendicular to the arrows A1, A2, Z1, and Z2 is the width direction (left-right direction) of the work machine 1. The front side of Fig. 2 is the left side of the work machine 1, and the back side is the right side of the work machine.

[0038] A connecting section 8 is provided at the rear of the vehicle body 3. The connecting section 8 is configured with a three-point link mechanism or the like. The working device 2 can be detachably connected to the connecting section 8. By connecting the working device 2 to the connecting section 8 and driving the traveling device 7, the working machine 1 (vehicle body 3) can travel and tow the working device 2. The connecting section 8 can also be used to raise and lower the working device 2 and change the attitude of the working device 2.

[0039] The work equipment 2 includes a tilling equipment for tilling, a fertilizer spreading equipment for spreading fertilizer, a pesticide spreading equipment for spreading pesticide, a harvesting equipment for harvesting, a reaping equipment for cutting grass etc., a spreading equipment for spreading grass etc., a grass collecting equipment for collecting grass etc., a shaping equipment for shaping grass etc., and the like.

[0040] A hood 12 is provided in front of the cabin 9. The hood 12 is attached to the vehicle body 3. A housing room (reference numeral omitted) is formed between the hood 12 and the vehicle body 3. The housing room houses not only the engine 4 but also a cooling fan, a radiator, a battery, and the like (not shown).

[0041] Figure 3 is a block diagram showing the electrical configuration of the work machine 1 shown in Figure 1A etc. The work machine 1 is provided with a control device 21, a wireless communication device 23, a position detection device 24, a monitoring device 25, a state detection device 26, an actuator group 27, and a work machine 2. These components are electrically connected by an on-board communication network such as CAN, LIN, or FlexRay that is configured in the work machine 1.

[0042] The control device 21 is composed of an ECU (electronic control unit) including a CPU and memory. The control device 21 controls the operation of each part of the work machine 1. The control device 21 is provided with a travel control unit 21b, a work control unit 21c, a first assignment unit 21d, and a memory unit 21e. The memory unit 21e is composed of volatile or non-volatile memory, etc. Various types of information and data used by the control device 21 to control the operation of each part of the work machine 1 are stored in a readable and writable manner in the memory unit 21e. The travel control unit 21b, the work control unit 21c, and the first assignment unit 21d are composed of software programs or hardware.

[0043] The wireless communication device 23 performs wireless communication via a mobile phone communication network 51 or the Internet 50. The wireless communication device 23 can also perform wireless communication via a wireless LAN.

[0044] The position detection device 24 is installed, for example, on top of the cabin 9 (FIG. 2) (details not shown). The installation location of the position detection device 24 is not limited to the top of the cabin 9, but may be another location on the vehicle body 3 or a predetermined location on the work device 2. The position detection device 24 detects its own position (positioning information including latitude and longitude) using a satellite positioning system. That is, the position detection device 24 receives signals transmitted from positioning satellites (position of the positioning satellite, transmission time, correction information, etc.) and detects its own position based on the signals. The position detection device 24 may detect, as its own position, a position corrected based on signals such as corrections from a base station (reference station) that can receive signals from positioning satellites.

[0045] The position detection device 24 may also have an inertial measurement device such as a gyro sensor or an acceleration sensor. In this case, the position detection device 24 may correct the position (latitude, longitude) detected based on a signal received from a positioning satellite using the inertial measurement device, and detect the corrected position as its own position. The position detection device 24 considers its own detected position to be the position of the work implement 1. Alternatively, the position detection device 24 may calculate the position of the work implement 1 based on its own detected position and pre-stored external shape information of the work implement 1. The position detection device 24 may also calculate the position of the work implement 2 based on its own detected position, pre-stored external shape information of the work implement 2, and the mounting position of the work implement 2 relative to the vehicle body 3.

[0046] The monitoring device 25 has a laser sensor 25a, an ultrasonic sensor 25b, a camera 25c, and an object detection unit 25d. The laser sensor 25a, the ultrasonic sensor 25b, and the camera 25c are installed at appropriate locations such as the front, rear, left and right sides, or top of the work machine 1 (details not shown), and detect the conditions around the work machine 1. Note that at least one of the laser sensor 25a, the ultrasonic sensor 25b, and the camera 25c may be provided in the monitoring device 25. Furthermore, the monitoring device 25 may be provided with detection means such as sensors other than these.

[0047] The laser sensor 25a is an optical sensor such as a LiDAR (Light Detection And Ranging) sensor. The laser sensor 25a emits pulsed measurement light (laser light) millions of times per second from a light source such as a laser diode, and reflects the measurement light with a rotating mirror to scan the measurement light in the horizontal or vertical direction and project it onto a predetermined detection range (sensing range). The laser sensor 25a then receives the measurement light reflected by the target object with a light-receiving element.

[0048] The object detection unit 25d detects the presence or absence of an object, the position of the object, the type of the object, etc. based on the light receiving signal output from the light receiving element of the laser sensor 25a. The object detection unit 25d also detects the distance to the object based on the time from when the laser sensor 25a emits measurement light to when it receives reflected light (TOF (Time of Flight) method). The objects detected by the object detection unit 25d include the work site where the work machine 1 travels and works, the field, crops in the field, the ground, the road surface, other objects, obstacles, people, etc.

[0049] The ultrasonic sensor 25b is an airborne ultrasonic sensor such as a sonar. The ultrasonic sensor 25b transmits measurement waves (ultrasonic waves) within a predetermined detection range using a transmitter, and receives the reflected waves from an object using a receiver. The object detection unit 25d detects the presence or absence of an object, its position, and the type of object based on the signal output from the receiver of the ultrasonic sensor 25b. The object detection unit 25d also detects the distance to the object based on the time between when the ultrasonic sensor 25b transmits the measurement wave and when it receives the reflected wave (TOF method).

[0050] The camera 25c is an imaging device such as a CCD camera equipped with a CCD (Charge Coupled Devices) image sensor or a CMOS camera equipped with a CMOS (Complementary Metal Oxide Semiconductor) image sensor. The camera 25c captures an image of the surroundings of the work machine 1 and outputs an image signal. The object detection unit 25d detects the presence or absence of an object, the position of the object, the type of the object, etc. based on the image signal output from the camera 25c.

[0051] Monitoring device 25 monitors the conditions around work machine 1 and work device 2 using laser sensor 25a, ultrasonic sensor 25b, camera 25c, and object detection unit 25d, and outputs monitoring data indicating the monitoring results to control device 21. This monitoring data includes at least image data captured by camera 25c and detection data of objects detected by object detection unit 25d.

[0052] When the control device 21 acquires monitoring data from the monitoring device 25, the first assigning unit 21d assigns a first timestamp to the monitoring data. The control device 21 transmits the monitoring data with the assigned first timestamp to the support device 40 via the wireless communication device 23. The control device 21 transmits the monitoring data and the assigned first timestamp at a predetermined interval or in response to a request from the support device 40.

[0053] The state detection device 26 includes various sensors installed in various parts of the work machine 1 or work device 2. The state detection device 26 detects the operating states of the work machine 1 and work device 2, such as travel and work, based on output signals from the various sensors. The state detection device 26 also acquires the positions (position of the work machine 1, position of the work device 2) detected by the position detection device 24 at a predetermined cycle, and detects changes (transitions) in these positions as the operating states of the work machine 1 and work device 2. The state detection device 26 then generates operation detection data that indicates the detection results of the operating states of the work machine 1 and work device 2, and outputs this operation detection data to the control device 21.

[0054] The actuator group 27 includes electric or hydraulic motors, cylinders, control valves, etc. for operating various parts of the work machine 1, such as the traveling device 7, the transmission 5, the prime mover 4, and the connecting part 8. The traveling control part 21b of the control device 21 operates predetermined actuators included in the actuator group 27 to drive the traveling device 7, the transmission 5, the prime mover 4, etc., and control the traveling of the work machine 1.

[0055] The work control unit 21c communicates with the control unit 2a provided in the work apparatus 2 and causes the control unit 2a to control the operation of the work apparatus 2. In other words, the work control unit 21c controls the work performed by the work apparatus 2 via the control unit 2a.

[0056] The control device 21 controls the travel of the work machine 1 by the travel control unit 21b, controls the work operation by the work control unit 21c, or also controls other operations of the work machine 1, based on the monitoring data output from the monitoring device 25, the operation detection data output from the state detection device 26, the position of the work machine 1 output from the position detection device 24, etc. Furthermore, when the control device 21 receives a remote control signal transmitted from the remote control terminal 30 by the wireless communication device 23, it controls the travel, work operation, and other operations of the work machine 1 etc. (or the work device 2) based on the remote control signal in addition to the above data.

[0057] Furthermore, when the control device 21 controls the travel or work of the work machine 1, etc., if the object detection unit 25d detects that there is an object in the travel direction of the work machine 1 or the operation direction of the work device 2, the control device 21 controls the travel device 7 or the work device 2, etc., to stop the travel or work and avoid a collision with the object (collision avoidance operation).

[0058] FIG. 4 is a block diagram showing the electrical configuration of the remote control terminal 30 shown in FIG. 1A etc. The remote control terminal 30 is provided with a control unit 31, a storage unit 32, a communication unit 33, and a display operation unit 34. The control unit 31 is composed of a CPU etc. The control unit 31 controls the operation of each unit of the remote control terminal 30. The control unit 31 is provided with a second assigning unit 31d. The second assigning unit 31d is composed of a software program. As another example, the second assigning unit 31d may be composed of hardware separate from the control unit 31.

[0059] The storage unit 32 is composed of a volatile or non-volatile memory, etc. The storage unit 32 stores various information and data in a readable and writable manner, which is used by the control unit 31 to control the operation of each unit of the remote control terminal 30. The communication unit 33 communicates wirelessly via a mobile phone communication network 51 or the Internet 50. The communication unit 33 can also communicate wirelessly via a wireless LAN.

[0060] The display operation unit 34 is configured from, for example, a touch panel and hardware switches. Information for remotely controlling the work machine 1 is displayed on the display operation unit 34. Operations for remotely controlling the work machine 1 can also be performed using the display operation unit 34. As another example, instead of the display operation unit 34, a separate display unit and operation unit may be provided in the remote control terminal 30.

[0061] When the operator 60 operates the display operation unit 34 to input an operation instruction for the work machine 1, the control unit 31 generates a remote operation signal corresponding to the operation instruction. The second assigning unit 31d assigns a second timestamp to the generated remote operation signal. The control unit 31 transmits the remote operation signal with the second timestamp assigned to it via the communication unit 33 to the support device 40.

[0062] FIG. 5 is a block diagram showing the electrical configuration of the support device 40 shown in FIG. 1A and other figures. The support device 40 is provided with a control unit 41, a storage device 42, and a communication unit 43. The control unit 41 is composed of a CPU and other components. The control unit 41 controls the operation of each component of the support device 40. The control unit 41 is provided with a signal receiving unit 41a. The signal receiving unit 41a has a digital filter 41b. The signal receiving unit 41a is configured by a software program. As another example, the signal receiving unit 41a may be configured by hardware separate from the control unit 41. Furthermore, the digital filter 41b may be configured separately from the signal receiving unit 41a.

[0063] The storage device 42 is composed of a non-volatile memory or a hard disk, etc. A work database 42a and a monitoring database 42d are constructed in the storage device 42. The work database 42a stores (saves) multiple pieces of work data for the work machine 1 to perform work. The monitoring database 42d stores (saves) multiple pieces of monitoring data from the monitoring device 25 (FIG. 3).

[0064] The communication unit 43 communicates wirelessly or via a wired connection via a mobile phone communication network 51 or a fixed telephone communication network 52 and the Internet 50. The communication unit 43 can also communicate via a wireless or wired LAN.

[0065] The monitoring data and the first timestamp assigned thereto transmitted from the wireless communication device 23 of the work machine 1 are received by the communication unit 43 of the support device 40. The control unit 41 stores (preserves) the monitoring data received by the communication unit 43 and the first timestamp assigned thereto in the monitoring database 42d of the storage device 42.

[0066] The monitoring data stored in the monitoring database 42d of the storage device 42 and the work data stored in the work database 42a are read by the control unit 41 in response to a request from the remote control terminal 30, and are transmitted to the remote control terminal 30 by the communication unit 43. When the monitoring data is transmitted to the remote control terminal 30, the first timestamp assigned to the monitoring data is also transmitted to the remote control terminal 30 by the communication unit 43.

[0067] The remote control signal transmitted from the remote control terminal 30 is received by the communication unit 43 of the support device 40 and accepted by the signal accepting unit 41a. The signal accepting unit 41a determines whether the accepted remote control signal is appropriate based on the second timestamp assigned to the accepted remote control signal and the first timestamp assigned to the monitoring data stored in the monitoring database 42d of the storage device 42.

[0068] If the signal receiving unit 41a determines that the received remote control signal is appropriate, it validates the remote control signal by transferring it to the wireless communication device 23 of the work machine 1 via the communication unit 43. On the other hand, if the signal receiving unit 41a determines that the received remote control signal is inappropriate, it invalidates the remote control signal by discarding it without transferring it. The digital filter 41b filters image data (image signals) included in the monitoring data read out from the monitoring database 42d.

[0069] 6A and 6B are diagrams showing a remote monitoring operation screen G1 displayed on the display operation unit 34 of the remote control terminal 30. For example, when an operator 60 (FIG. 1B) performs a predetermined operation on the display operation unit 34, the control unit 31 executes (launches) an application program for remotely controlling the work machine 1 (hereinafter referred to as a "remote control app"), and displays the remote monitoring operation screen G1 shown in FIG. 6A etc. on the display operation unit 34. The remote monitoring operation screen G1 is provided with input fields J1 to J3, operation keys B1 to B6, display fields D1 and D2, and notification fields M1 and M2.

[0070] The operator 60 enters the name of the field where the work will be performed with the work implement 1 (field identification information) into the field input field J1, the model of the work implement 1 (work implement identification information) into the model input field J2, the type of work (work identification information) into the work input field J3, and then touches the enter key B1. In response to this operation, the control unit 31 reads out work data corresponding to the input contents of the input fields J1 to J3 from the memory unit 32. If work data corresponding to the input contents of the input fields J1 to J3 is not stored in the memory unit 32, the control unit 31 generates a work request signal corresponding to the input contents and transmits the work request signal to the support device 40 via the communication unit 33.

[0071] In the support device 40, when the communication unit 43 receives the task request signal, the control unit 41 reads out task data corresponding to the task request signal from the task database 42a (FIG. 5) and transmits the task data to the remote control terminal 30.

[0072] When the control unit 31 of the remote control terminal 30 reads out work data from the storage unit 32 or receives work data via the communication unit 33, it displays the work information indicated by the work data in the work display field D1 of the remote monitoring operation screen G1. Furthermore, when the control unit 31 receives work data via the communication unit 33, it stores the work data in the storage unit 32.

[0073] As shown in Figure 6A, the work information displayed in the work display field D1 includes a field map MP2 showing the field H1 entered in the field input field J1, and a driving route L1 along which the work implement 1 entered in the model input field J2 will travel in the field H1 when performing the work entered in the work input field J3.

[0074] The travel route L1 includes a straight section L1a, a turning section L1b, a start position Ps, and an end position Pg. The start position Ps is the position where the work machine 1 starts traveling to perform work. The straight section L1a is a route along which the work machine 1 performs work using the work implement 2 while traveling straight. The turning section L1b is a route along which the work machine 1 turns from one straight section L1a to the next straight section L1a. When the work machine 1 is turning along the turning section L1b, work by the work implement 2 is stopped. The end position Pg is the position where the work machine 1 ends (stops) work and traveling.

[0075] Furthermore, when the enter key B1 is touched, the control unit 31 generates a monitoring request signal requesting monitoring data and transmits the monitoring request signal to the support device 40 via the communication unit 33. In the support device 40, when the communication unit 43 receives the monitoring request signal, the control unit 41 reads out the monitoring data corresponding to the monitoring request signal from the monitoring database 42d (FIG. 5) and transmits the monitoring data to the remote control terminal 30 via the communication unit 43. At this time, the control unit 41 reads out the latest monitoring data and the first timestamp assigned to the monitoring data from the monitoring data stored in the monitoring database 42d and transmits them via the communication unit 43.

[0076] In the remote control terminal 30, when the communication unit 33 receives monitoring data, the control unit 31 stores the monitoring data and the first timestamp assigned to it in the memory unit 32, and then displays the monitoring results (monitoring information) indicated by the monitoring data in the display fields D2, D1 and notification field M2 of the remote monitoring operation screen G1.

[0077] Specifically, the control unit 31 displays, in the monitoring display field D2, an image captured by the camera 25c (FIG. 3) of the monitoring device 25, among the monitoring results indicated by the monitoring data, as shown in FIG. 6A etc. The control unit 31 also displays, in the monitoring notification field M2, a message indicating the result of object detection by the object detection unit 25d (FIG. 3). Furthermore, the control unit 31 displays, in the work display field D1, a mark X1 indicating the position of the work implement 1 detected by the position detection device 24.

[0078] 6A and 6B, an overhead image of the area around the work machine 1 is displayed in the monitoring display field D2. This overhead image is created by the control unit 31 based on the monitoring data. Specifically, the monitoring data includes images of the front, rear, left, and right sides of the work machine 1 captured by multiple cameras 25c, and the control unit 31 combines these multiple images with a pre-stored work machine image X2 to create the overhead image. Furthermore, each time the operator 60 touches the image switching key B2, the control unit 31 switches the image displayed in the monitoring display field D2 in the following order: a front image, a rear image, a left image, a right image, and a bird's-eye image of the work machine 1 included in the monitoring data.

[0079] In the monitoring notification field M2, a message indicating the presence or absence of an object around the work machine 1 is displayed as an object detection result, for example. In FIG. 6A, a message indicating that there is no object around the work machine 1 is displayed in the monitoring notification field M2, but a message indicating the absence of the object does not have to be displayed. Furthermore, when a message indicating the presence of an object is displayed in the monitoring notification field M2, the distance to the object and the size of the object may also be displayed in the monitoring notification field M2. Each time the control unit 31 receives monitoring data from the support device 40 via the communication unit 33, the control unit 31 displays the monitoring results indicated by the monitoring data in the display fields D2, D1 and the notification field M2, and updates the display contents of the display fields D2, D1 and the notification field M2.

[0080] The operation notification field M1 displays the detection result of the operation state of the work machine 1 and the like by the state detection device 26 ( FIG. 3 ). In more detail, for example, the control unit 31 transmits an operation request signal requesting operation detection data indicating the detection result of the operation state of the work machine 1 and the like to the support device 40 via the communication unit 33. When the control unit 41 of the support device 40 receives the operation request signal via the communication unit 43, it transfers the operation request signal to the control device 21 of the work machine 1. When the control device 21 receives the operation request signal via the wireless communication device 23, it transmits the latest operation detection data output from the state detection device 26 to the support device 40 via the wireless communication device 23. When the control unit 41 of the support device 40 receives the operation detection data via the communication unit 43, it transfers the operation detection data to the remote control terminal 30. When the control unit 31 of the remote control terminal 30 receives the operation detection data via the communication unit 33, it displays the detection result of the operation state of the work machine indicated by the operation detection data in the operation notification field M1.

[0081] As a result of detecting the operation state of the work machine 1 etc., a message indicating, for example, whether the work machine 1 is traveling (traveling or stopped), whether the work device 2 is working (working or stopped), or whether remote control of the work machine 1 is being executed, is displayed in the operation notification field M1. Every time operation detection data is received by the communication unit 33, the control unit 31 displays the detection result indicated by the operation detection data in the operation notification field M1 and updates the display content of the operation notification field M1.

[0082] The travel work start key B3 and the travel work stop key B4 are examples of operation keys for remotely operating the work machine 1. By touching the travel work start key B3, the operator 60 can input an instruction to start the work machine 1 performing work by the work device 2 while automatically traveling and steering based on the travel route L1. In addition, by touching the travel work stop key B4, the operator 60 can input an instruction to stop the work machine 1 traveling and steering based on the travel route L1 and the work by the work device 2.

[0083] When the operator 60 touches the next key B5 or the previous key B6, other operation keys for remotely operating the work implement 1 are displayed in place of the operation keys B3 and B4. The other operation keys include, for example, a travel key for inputting a travel command for the work implement 1, a stop key for inputting a stop command for the work implement 1, a swing key for inputting a swing command for the work implement 1, a lift key for inputting a lift command for the work implement 2, a prime mover start key for inputting a start command for the prime mover 4 for warming up the work implement 1, or a prime mover stop key for inputting a stop command for the prime mover 4.

[0084] The operator 60 can input operation instructions for the work machine 1 by operating the operation keys B2, B3, etc. for remote operation of the work machine 1 while viewing the work information and monitoring results displayed in the display fields D1, D2 and notification field M1 of the remote monitoring operation screen G1.

[0085] 7A and 7B are flowcharts showing the operations of the control device 21, the support device 40, and the remote control terminal 30 of the work machine 1 of the first embodiment.

[0086] The monitoring device 25 of the work machine 1 outputs monitoring data indicating, for example, the results of monitoring the periphery of the work machine 1 to the control device 21 at a predetermined interval. When the control device 21 acquires the monitoring data (S1 in FIG. 7A), the first assigning unit 21d assigns a first timestamp to the monitoring data (S2). At this time, the first assigning unit 21d assigns, for example, a first timestamp indicating the current time to the monitoring data. The current time here refers to the time when the control device 21 acquired the monitoring data or the time when the control device 21 assigns the first timestamp. The control device 21 transmits the monitoring data with the assigned first timestamp together with the first timestamp to the support device 40 via the wireless communication device 23 (S3).

[0087] When the control unit 41 of the support device 40 acquires the monitoring data via the communication unit 43 (S4), it stores (preserves) the monitoring data together with the first timestamp assigned thereto in the monitoring database 42d of the storage device 42 (S5).

[0088] The control device 21 of the work machine 1 repeatedly executes steps S1 to S3 and S21 of FIG. 7A described above while not receiving a remote-operation signal (S21: NO in FIG. 7B). The control unit 41 of the support device 40 also repeatedly executes steps S4 and S5 of FIG. 7A described above and steps S9, S10, and S17 described below while not receiving a remote-operation signal (S17: NO in FIG. 7B). As a result, monitoring data indicating the monitoring results of the work machine 1 and its surroundings that are periodically output from the monitoring device 25 is stored (saved) as needed in the monitoring database 42d of the support device 40 together with the first timestamp attached thereto, and the monitoring data is accumulated.

[0089] The control unit 31 of the remote control terminal starts the remote control application and displays the remote monitoring operation screen G1 on the display operation unit 34 (S6 in FIG. 7A), then acquires task data corresponding to the input contents of the input fields J1 to J3 from the storage unit 32 or the support device 40, and displays the task contents indicated by the task data on the display operation unit 34 (S7). The control unit 31 also transmits a request signal for monitoring data to the support device 40 via the communication unit 33 (S8). At this time, the control unit 31 may also transmit a request signal for motion detection data to the support device 40 via the communication unit 33.

[0090] When the control unit 41 of the support device 40 receives a request signal for monitoring data via the communication unit 43 (S9: YES), it reads the latest monitoring data from the monitoring database 42d based on the request signal and transmits the monitoring data to the remote control terminal 30 via the communication unit 43 (S10).

[0091] When the control unit 31 of the remote control terminal 30 receives monitoring data via the communication unit 33 (S11), it displays the monitoring results indicated by the monitoring data in the display fields D1 and D2 and notification field M1 of the remote monitoring operation screen G1 (S12).

[0092] Then, while no operation instruction for the work machine 1 is input (S13: NO in FIG. 7B), the control unit 31 repeatedly executes the above-described processes S8, S11, S12, and S13 in FIG. 7A. Every time a request signal for monitoring data is received (S9: YES in FIG. 7A), the control unit 41 of the support device 40 reads the latest monitoring data from the monitoring database 42d and transmits it to the remote control terminal 30 (S10). As a result, the monitoring results of the work machine 1 and its surroundings, which are displayed on the remote monitoring operation screen G1 of the remote control terminal 30, are updated as needed.

[0093] For example, after the work machine 1 moves to a field where work will be performed, the operator 60 operates operation keys B2, B3 (e.g., FIG. 6A) on the remote monitoring operation screen G1 of the remote control terminal 30 to input an operation instruction for the work machine 1. As a result, the control unit 31 determines that an operation instruction for the work machine 1 has been input (S13: YES in FIG. 7B), and generates a remote operation signal corresponding to the operation instruction (S14).

[0094] Then, the second assigning unit 31d assigns a second timestamp to the generated remote control signal (S15). At this time, the second assigning unit 31d assigns the second timestamp, which indicates, for example, the current time, to the remote control signal. The current time here is the time when the control unit 31 generates the remote control signal, or the time when the control unit 31 assigns the second timestamp, for example.

[0095] Alternatively, the second assigning unit 31d refers to a first timestamp assigned to the monitoring data indicating the monitoring result displayed in the display fields D1, D2 and the notification field M1 when the remote operation keys B2, B3, etc. are operated, and assigns a second timestamp indicating a second time that is the same as the first time indicated by the first timestamp to the remote operation signal. The control unit 31 transmits the remote operation signal to which the second timestamp has been assigned, together with the second timestamp, to the support device 40 via the communication unit 33 (S16).

[0096] When the communication unit 43 of the support device 40 receives a remote control signal from the remote control terminal 30 (S17: YES), the signal receiving unit 41a receives the remote control signal and determines whether the remote control signal is appropriate (S18). At this time, the signal receiving unit 41a reads, from the monitoring database 42d, specific monitoring data to which a first timestamp indicating a first time that is the same as the second time indicated by the second timestamp added to the received remote control signal, or a first time that is earlier than the second time and closest to the second time, and the latest monitoring data.

[0097] The signal receiving unit 41a then passes the read specific monitoring data and the latest monitoring data through the digital filter 42b, compares the specific monitoring data with the latest monitoring data, and detects the difference between the two pieces of data. By passing the specific monitoring data and the latest monitoring data through the digital filter 42b, noise in both pieces of data can be removed and differences smaller than a predetermined value can be ignored.

[0098] Furthermore, when detecting a difference between specific monitoring data and the latest monitoring data, the signal receiving unit 41a compares the same type of monitoring data of both monitoring data to detect the difference. That is, the signal receiving unit 41a compares image data from the cameras 25c, detection data from the laser sensors 25a, detection data from the ultrasonic sensors 25b, and detection data from the object detection unit 25d to detect the difference between each piece of data. The signal receiving unit 41a may also compare at least one type of data among the image data from the cameras 25c, detection data from the laser sensors 25a, detection data from the ultrasonic sensors 25b, and detection data from the object detection unit 25d to detect the difference.

[0099] When there is no communication delay of a predetermined time or more in the communication between the remote control terminal 30 and the assistance device 40, the real-timeness of the monitoring results (monitoring data) of the surroundings of the work machine 1 displayed on the remote control terminal 30 and the remote operation signal transmitted from the remote control terminal 30 is ensured to a certain extent. In this case, for example, when a remote operation signal is transmitted from the remote control terminal 30 in response to the traveling operation start key B3 while the work machine 1 is stopped, the signal receiving unit 41a of the assistance device 40 receives the remote operation signal and reads out specific monitoring data and the latest monitoring data from the monitoring database 42d. The state of the surroundings of the work machine 1 shown in the specific monitoring data read out at this time (i.e., the monitoring data displayed on the remote control terminal 30) and the state of the surroundings of the work machine 1 shown in the latest monitoring data are approximately the same, so that objects not shown in the specific monitoring data will not be shown in the latest monitoring data.

[0100] Furthermore, if there is no communication delay of a predetermined time or more in the communication between the remote control terminal 30 and the assistance device 40, for example, when a remote control signal based on a turn key instructing the work machine 1 to turn is sent from the remote control terminal 30 while the work machine 1 is traveling, the signal receiving unit 41a receives the remote control signal and reads out specific monitoring data and the latest monitoring data from the monitoring database 42d. Even in this case, there is little change in the state of the surroundings of the work machine 1 shown in the latest monitoring data compared to the state of the surroundings of the work machine 1 shown in the read specific monitoring data, and objects not shown in the specific monitoring data will not be shown in the latest monitoring data.

[0101] In other words, if there is no communication delay of more than a predetermined time in the communication between the remote control terminal 30 and the support device 40, the difference between the specific monitoring data detected by the signal receiving unit 41a and the latest monitoring data, i.e., the difference between the image data of the camera 25c included in both monitoring data, the detection data of the laser sensor 25a included in both monitoring data, the detection data of the ultrasonic sensor 25b included in both monitoring data, and the detection data of the object detection unit 25d included in both monitoring data, is small, and the difference does not exceed a predetermined level (threshold value).

[0102] Note that, since the conditions around the work machine 1 change while the work machine 1 is traveling, the predetermined degree (threshold) that the signal receiving unit 41a uses to compare with the difference may be set to be greater than the predetermined degree that is used to compare with the difference while the work machine 1 is stopped. Alternatively, while the work machine 1 is traveling, the signal receiving unit 41a may detect the difference between the specific monitoring data and the latest monitoring data, between the detection data of the laser sensor 25a, between the detection data of the ultrasonic sensor 25b, or between the detection data of the object detection unit 25d, and compare it with a predetermined degree, but may not detect the difference between the image data of the cameras 25c or compare it with the predetermined degree.

[0103] Furthermore, if the intervals at which monitoring data is stored in the monitoring database 42d are long or the intervals at which monitoring data is received by the remote control terminal 30 are short, the specific monitoring data that the signal receiving unit 41a reads from the monitoring database 42d may be the same as the latest monitoring data. Even in this case, the difference between the specific monitoring data detected by the signal receiving unit 41a and the latest monitoring data does not exceed a predetermined level.

[0104] If the detected difference does not exceed a predetermined level, the signal receiving unit 41a determines that the received remote control signal is appropriate (S19: YES) and activates the remote control signal by transferring it to the control device 21 of the work machine 1 (S20).

[0105] When the control device 21 of the work machine 1 receives a remote control signal via the wireless communication device 23 (S21: YES), it controls the operation of the work machine 1 (or work device 2) using the travel control unit 21b or the work control unit 21c based on the remote control signal (S22). In other words, the control device 21 is allowed to control the operation of the work machine 1 or work device 2 based on the remote control signal transmitted from the remote control terminal 30, and the work machine 1 or work device 2 performs the operation corresponding to the remote control signal.

[0106] If the remote control signal transmitted from the remote control terminal 30 is a remote control signal based on the operation of the travel work start key B3 (e.g., FIG. 6A), the remote control terminal 30 also transmits work data together with the remote control signal (S16 in FIG. 7B). Then, if the remote control signal is validated by the signal receiving unit 41a of the support device 40 (S20), the wireless communication device 23 of the work implement 1 receives the work data together with the remote control signal (S21: YES). Therefore, the control device 21 controls the operation of the work implement 1 or work implement 2 using the travel control unit 21b or work control unit 21c based on the received remote control signal and the travel route L1 included in the work data, and performs agricultural work in the field using the work implement 2 while automatically traveling and steering the work implement 1. As another example, the control device 21 may acquire (receive) work data from the support device 40 at a predetermined timing.

[0107] On the other hand, if there is a communication delay of a predetermined time or more in the communication between the remote control terminal 30 and the assistance device 40, the real-timeness of the monitoring results (monitoring data) of the surroundings of the work machine 1 displayed on the remote control terminal 30 and the remote control signal transmitted from the remote control terminal 30 is impaired. In this case, for example, if a remote control signal is transmitted from the remote control terminal 30 based on the travel operation start key B3 while the work machine 1 is stopped, or if a remote control signal is transmitted from the remote control terminal 30 based on the turn key while the work machine 1 is traveling, the signal receiving unit 41a receives the remote control signal and reads specific monitoring data and the latest monitoring data from the monitoring database 42d. An object (an obstacle, e.g., a moving object such as a bird or animal) not indicated in the specific monitoring data read at this time may be indicated in the latest monitoring data. Furthermore, while the work machine 1 is traveling, the surrounding conditions of the work machine 1 indicated in the specific monitoring data may change significantly compared to the surrounding conditions of the work machine 1 indicated in the latest monitoring data.

[0108] Therefore, if there is a communication delay of a predetermined time or more in the communication between the remote control terminal 30 and the assistance device 40, the difference between the specific monitoring data detected by the signal receiving unit 41a and the latest monitoring data becomes large, and the difference exceeds a predetermined level (threshold value). If the difference exceeds the predetermined level, the signal receiving unit 41a determines that the received remote control signal is inappropriate (S19: NO) and invalidates the remote control signal by discarding it without transferring it to the control device 21 (S23). Then, the signal receiving unit 41a transmits an invalidation notice (signal) indicating that the remote control signal has been invalidated to the remote control terminal 30 via the communication unit 43 (S24). This prevents the control device 21 from controlling the operation of the work machine based on the remote control signal transmitted from the remote control terminal 30.

[0109] When the control unit 31 of the remote control terminal 30 receives the invalidation notification via the communication unit 33 (S25), it displays the contents of the invalidation notification in the operation notification field M1 (S26). In detail, the control unit 31 displays a message in the operation notification field M1, as shown in Fig. 6B, indicating that the remote operation indicated in the invalidation notification (the input operation instruction for the work machine 1) has been invalidated. This allows the operator 60 to recognize that the input operation instruction for the work machine 1, i.e., the remote operation, has not been executed.

[0110] In the above-described embodiment, the signal receiving unit 41a of the support device 40 reads specific monitoring data and the latest monitoring data from the monitoring database 42d based on the second time indicated by the second timestamp attached to the remote control signal and the first time indicated by the first timestamp attached to the monitoring data stored in the monitoring database 42d, and determines the appropriateness of the remote control signal based on the difference between these. However, the method for determining the appropriateness of the remote control signal is not limited to this, and the following determination method may also be adopted.

[0111] For example, the signal receiving unit 41a determines whether the remote control signal is appropriate based on the time difference between the second time indicated by the second timestamp added to the remote control signal and the first time indicated by the first timestamp added to the latest monitoring data. Specifically, if the time difference between the second time indicated by the second timestamp of the remote control signal and the first time indicated by the first timestamp of the latest monitoring data is less than a predetermined time, the delay time is short, and the signal receiving unit 41a determines that the remote control signal is appropriate. On the other hand, if the time difference between the second time and the first time is equal to or greater than the predetermined time, the delay time is long, and the signal receiving unit 41a determines that the remote control signal is inappropriate.

[0112] Alternatively, the signal receiving unit 41a determines the appropriateness of the received remote control signal based on the operation instruction corresponding to the signal. Specifically, for example, if the operation instruction corresponding to the received remote control signal is an instruction to stop the work machine 1 while the work machine 1 is traveling, the risk is low and the signal receiving unit 41a determines that the remote control signal is appropriate. Also, even if the operation instruction corresponding to the received remote control signal is an instruction to start the prime mover 4 or an operation instruction unrelated to the travel and work of the work machine 1, the risk is low and the signal receiving unit 41a determines that the remote control signal is appropriate. Also, if the operation instruction corresponding to the received remote control signal is an instruction to lower the work implement 2 while the work machine 1 is swinging, the risk is high if the work implement 2 lands, and the signal receiving unit 41a determines that the remote control signal is inappropriate.

[0113] Furthermore, as shown in Fig. 8, the signal receiving unit 41a may determine the appropriateness of a remote control signal. Fig. 8 is a flowchart showing the operation of the support device 40 of another embodiment. In the example of Fig. 8, when the communication unit 43 of the support device 40 receives a remote control signal (S17: YES), the signal receiving unit 41a receives the remote control signal (S18a) and checks whether the operation instruction corresponding to the remote control signal is an operation instruction related to the travel of the work machine 1 or the work performed by the work device 2. Here, if the operation instruction corresponding to the received remote control signal is an operation instruction related to the travel of the work machine 1 or the work performed by the work device 2 (S18b: YES), the signal receiving unit 41a determines the appropriateness of the remote control signal (S18c).

[0114] On the other hand, if the operation instruction corresponding to the received remote control signal is neither an operation instruction related to the travel of the work implement 1 nor an operation instruction related to work by the work implement 2 (S18b: NO), the signal receiving unit 41a does not determine the appropriateness of the remote control signal, but instead transfers the remote control signal to the control device 21 of the work implement 1 to enable it (S20). The other processes of the support device 40 are the same as those described in Figures 7A and 7B.

[0115] The output of monitoring data from the monitoring device 25, the transmission of monitoring data or motion detection data from the wireless communication device 23, or the transmission of monitoring data or motion detection data from the assistance device 40 may be performed at a predetermined interval or in response to a request from the receiving device.

[0116] In the embodiment described above, as shown in Fig. 1B etc., the storage device 42 in which the databases 42d, 42a are constructed and the signal receiving unit 41a are provided in the support device 40, but for example, as shown in Figs. 9 to 11, one of the storage device 42 and the signal receiving unit 41a may be provided in the work machine 1 (or work machine 2), or both may be provided in the work machine 1 (or work machine 2). Figs. 9 to 11 are configuration diagrams of a work machine remote control system 100 of another embodiment.

[0117] In the work machine remote control system 100 shown in Fig. 9, the storage device 22 in which the monitoring database 22d is constructed is provided in the work machine 1. In other words, the monitoring database 22d is not provided in the support device 40. The installation locations of other components are the same as those in the embodiment shown in Figs. 1B to 5.

[0118] 9 , the monitoring data output from the monitoring device 25 of the work machine 1 to the control device 21 is assigned a first timestamp by the first assigning unit 21d, and then stored in the monitoring database 22d of the storage device 22 by the control device 21. The remote control terminal 30 transmits a first monitoring request signal requesting the monitoring data to the support device 40 via the communication unit 33. The support device 40 receives the first monitoring request signal via the communication unit 43 and transfers it to the wireless communication device 23 of the work machine 1. In response to the first monitoring request signal received by the wireless communication device 23, the control device 21 reads out the monitoring data (the latest monitoring data) from the monitoring database 22d and transmits the monitoring data to the support device 40 via the wireless communication device 23. The support device 40 receives the monitoring data via the communication unit 43 and transfers the monitoring data to the remote control terminal 30.

[0119] 9, when the signal receiving unit 41a of the support device 40 receives a remote control signal transmitted from the remote control terminal 30 via the communication unit 43, the signal receiving unit 41a transmits a second monitoring request signal requesting monitoring data corresponding to the remote control signal to the control device 21 of the work machine 1 via the communication unit 43. When the control device 21 receives the second monitoring request signal via the wireless communication device 23, the control device 21 reads the monitoring data requested by the second monitoring request signal from the monitoring database 22d. At this time, the control device 21 reads from the monitoring database 22d specific monitoring data assigned a first timestamp indicating a first time that is the same as the second time indicated by the second timestamp assigned to the remote control signal that triggered (triggered) the transmission of the second monitoring request signal, or a first time that is earlier than and closest to the second time, and the latest monitoring data. Then, when this monitoring data is transmitted to the support device 40 via the wireless communication device 23, the signal receiving unit 41a acquires the monitoring data via the communication unit 43. The operation of each of the other units is the same as the operation of each unit described with reference to FIGS. 1A to 8.

[0120] 5 may also be constructed in the storage device 22 of the work machine 1 (not shown) rather than being provided in the support device 40. In this case, the work data in the work database 42a constructed in the storage device 22 is transmitted from the storage device 22 of the work machine 1 to the remote control terminal 30 via the support device 40 in the same manner as the monitoring data described above.

[0121] In the work machine remote control system 100 shown in Fig. 10, the signal receiving unit 41a (Fig. 5, etc.) is not provided in the support device 40, but the signal receiving unit 21a is provided in the work machine 1. The installation locations of other components are the same as in the embodiment shown in Figs. 1B to 5.

[0122] 10 , a remote control signal transmitted from the remote control terminal 30 is received by the wireless communication device 23 of the work machine 1 via the communication unit 43 of the support device 40 and accepted by the signal accepting unit 21a. The signal accepting unit 21a then transmits a second monitoring request signal, requesting monitoring data corresponding to the accepted remote control signal, to the support device 40 via the wireless communication device 23. Upon receiving the second monitoring request signal via the communication unit 43, the control unit 41 of the support device 40 reads the monitoring data requested by the second monitoring request signal from the monitoring database 42d of the storage device 42. At this time, the control unit 41 reads from the monitoring database 42d specific monitoring data assigned a first timestamp that is the same as the second time indicated by the second timestamp assigned to the remote control signal that was the basis of the second monitoring request signal, or a first timestamp that is earlier than and closest to the second time, as well as the latest monitoring data. Then, the monitoring data is transmitted by the communication unit 43 to the wireless communication device 23, and the signal receiving unit 21a acquires (receives) the monitoring data from the wireless communication device 23.

[0123] When signal receiving unit 21a acquires the specific monitoring data and the latest monitoring data as described above, it detects the difference between the specific monitoring data and the latest monitoring data, similar to signal receiving unit 41a (FIG. 5, etc.), determines the appropriateness of the remote control signal based on the difference, and activates or deactivates the remote control signal depending on the determination result. Based on the remote control signal that has been activated (determined to be appropriate) by signal receiving unit 21a, control device 21 controls the operation of work implement 1 and work device 2 using travel control unit 21b or work control unit 21c. The operation of each of the other parts is the same as the operation of each part described with reference to FIGS. 1A to 8.

[0124] In the remote control system 100 for a work machine shown in FIG. 11, a storage device 22 and a signal receiving unit 21a are provided in the work machine 1. The installation locations of other components are the same as those in the embodiment shown in FIGS. 1B to 5. In FIG. 11, an assistance device 40 relays a first monitoring request signal, monitoring data, remote operation signals, etc. between the wireless communication device 23 of the work machine 1 and the remote control terminal 30. A communication unit 43 of the assistance device 40 communicates wirelessly or wired with the wireless communication device 23 of the work machine 1 and the communication unit 33 of the remote control terminal 30 via a mobile phone communication network 51, a fixed telephone communication network 52, or a LAN (local area network) 53 and the Internet 50. The operation of each of the other units is the same as that of each unit described with reference to FIGS. 1A to 8 or 9.

[0125] In the embodiment described above, the support device 40 is included in the work machine remote control system 100, but the support device may be omitted, as in another embodiment of the work machine remote control system 100 shown in Fig. 12. In the work machine remote control system 100 shown in Fig. 12, the wireless communication device 23 of the work machine 1 and the remote control terminal 30 communicate wirelessly via a LAN 53, a mobile phone communication network 51, a fixed telephone communication network 52, the Internet 50, or the like. The work machine 1 is provided with a memory device 22 and a signal receiving unit 21a.

[0126] 12, the remote control terminal 30 transmits a monitoring request signal requesting monitoring data to the wireless communication device 23 of the work machine 1 via the communication unit 33. When the wireless communication device 23 receives the monitoring request signal, the control device 21 of the work machine 1 reads out the monitoring data from the monitoring database 22d in the storage device 22 and transmits it to the remote control terminal 30 via the wireless communication device 23. The work data stored in the work database 22a is also transmitted from the wireless communication device 23 to the remote control terminal 30 in the same procedure as the above-mentioned monitoring data.

[0127] Furthermore, the remote control terminal 30 transmits a remote control signal to the wireless communication device 23 via the communication unit 33. When the wireless communication device 23 receives the remote control signal, the signal reception unit 21a receives the remote control signal and reads, from the monitoring database 22d, specific monitoring data to which a first timestamp indicating a first time that is the same as the second time indicated by the second timestamp added to the remote control signal or a first time that is earlier than the second time and closest to the second time, and the latest monitoring data. The signal reception unit 21a then determines the appropriateness of the received remote control signal based on the difference between the specific monitoring data and the latest monitoring data, and activates or deactivates the remote control signal depending on the determination result. The operations of the other components are the same as those of the components described in FIGS. 1A to 8, 9, or 10.

[0128] In another embodiment, the wireless communication device 23 of the work machine 1 and the remote control terminal 30 may directly communicate monitoring data and remote operation commands using short-range wireless signals such as infrared signals, BLU (Bluetooth (registered trademark) Low Energy) signals, or UHF (Ultra High Frequency) signals, without using a network. In this case, the wireless communication device 23 and the remote control terminal 30 may each be provided with an interface for short-range wireless communication. The remaining configuration may be the same as the configuration shown in FIG. 12.

[0129] In the above-described embodiment, an example has been shown in which the monitoring data transmitted to the remote control terminal 30 includes image data of the surroundings of the work machine 1 captured by the camera 25c, but for example, the camera 25c may be omitted, and data indicating the surrounding conditions of the work machine 1 and the like detected by a sensor and the object detection unit 25d may be transmitted as monitoring data from the wireless communication device 23 of the work machine 1 or the support device 40 to the remote control terminal 30. In this case, for example, a display unit 38 as shown in Fig. 13 may be provided on the remote control terminal 30.

[0130] The display unit 38 shown in Fig. 13 may be, for example, a screen displayed on a touch panel, or may be formed by processing such as printing and molding on the surface of the remote control terminal 30. In the latter case, the display field D2a and notification fields M1a and M2a may be respectively formed by printed characters and indicator lamps 39a to 39k (circles shown in Fig. 13), and push-button type operation keys B3a and B4a may be provided. The indicator lamps 39a to 39k are formed by LEDs or the like.

[0131] For example, when an object is detected around the work machine 1 and the work implement 2 by the laser sensor 25a or the ultrasonic sensor 25b and the object detection unit 25d, the control unit 31 of the remote control terminal 30, which has received monitoring data including the detection results, lights up indicator lamps 39a to 39h in the display field D2a corresponding to the direction of the object (as indicated by hatching). The control unit 31 also lights up indicator lamps 39i and 39j in the corresponding notification field M1a to notify the vehicle status of whether the work machine 1 and the work implement 2 are stopped or in operation. The control unit 31 also lights up indicator lamp 39k in the corresponding notification field M2a to notify that the remote operation signal has been disabled. The travel and work start key B3a is operated to input an instruction to start work by the work implement 2 while the work machine 1 automatically travels and steers based on the travel route L1. The travel work stop key B4a is operated to input a command to stop the work implement 2 from performing work while the work implement 1 is automatically traveling and steering based on the travel route L1.

[0132] In the above-described embodiment, the remote control signal determined by the signal receiving unit 41a to be inappropriate is invalidated by discarding it without transferring it to the control device 21. However, the invalidation method is not limited to this. For example, the remote control signal determined by the signal receiving unit 41a to be inappropriate may be returned together with an error message to the remote control terminal 30, rather than to the control device 21. Furthermore, if the signal receiving unit 21a is provided in the work machine 1, when the signal receiving unit 21a determines that the received remote control signal is inappropriate, the remote control signal may be invalidated by turning on a flag (referred to as a "remote control prohibition flag") that prohibits operational control of the work machine 1 (or the work machine 2) based on the remote control signal in a predetermined storage area of ​​the storage unit 21e (FIG. 3) of the control device 21. In this case, when the remote control prohibition flag is ON, the control device 21 does not execute operational control of the work machine 1, etc., based on the remote control signal received via the wireless communication device 23. Furthermore, the signal receiving unit 21a may turn off the remote control prohibition flag when a predetermined time has elapsed since the remote control prohibition flag was turned on, or when the next remote control signal is received.

[0133] In the above-described embodiment, the monitoring device 25 is provided in the work machine 1, but in addition to this, for example, a monitoring device that monitors the work machine 1 and the surrounding area of ​​the work machine 1 may be provided at the work site (such as a farm field) where the work machine 1 performs work. In this case, for example, the monitoring device may be provided with a communication unit that communicates wirelessly, and monitoring data indicating the monitoring results of the monitoring device may be transmitted by the communication unit to the wireless communication device 23 of the work machine 1, the remote control terminal 30, or the support device 40.

[0134] In the above-described embodiment, an example has been shown in which the wireless communication device 23 of the work machine 1, the communication unit 33 of the remote control terminal 30, or the communication unit 43 of the support device 40 communicate with each other via a mobile phone communication network 51, a fixed telephone communication network 52, the Internet 50, or a LAN 53. However, the communication networks are not limited to these. For example, the wireless communication device 23 and the communication units 33, 43 may communicate with each other via a wide area network or a narrow area network such as a WAN (World Area Network), a MAN (Metropolitan Area Network), a VPN (Virtual Private Network), Ethernet, or an intranet, or via a public communication network. Alternatively, the wireless communication device 23 and the communication units 33, 43 may communicate with each other via a combination of the above communication networks and other communication networks.

[0135] The remote control system 100 for a work machine according to the present embodiment described above has the following configuration and provides the following effects.

[0136] The remote control system 100 for a work machine of this embodiment includes a monitoring device 25 that monitors the periphery of the travellable work machine 1 and outputs monitoring data indicative of the monitoring results, a first assigning unit 21d that assigns a first timestamp to the monitoring data, storage devices 42, 22 that can store a plurality of pieces of monitoring data together with the first timestamps assigned to the monitoring data, a remote control terminal 30 that can receive the monitoring data and display the monitoring results indicated by the monitoring data and that transmits a remote operation signal to remotely operate the work machine 1 when operated, and a remote control unit 21d that assigns a second timestamp to the remote operation signal when the remote control terminal 30 transmits the remote operation signal. The system is equipped with a second timestamp assigning unit 31d that assigns a stamp, a signal receiving unit 41a, 21a that receives a remote control signal transmitted from the remote control terminal 30, and a control device 21 that controls the operation of the work machine 1, and the signal receiving units 41a, 21a determine the appropriateness of the remote control signal based on the second timestamp assigned to the received remote control signal and the first timestamp assigned to the monitoring data stored in the memory devices 42, 22, and invalidate any remote control signal that is determined to be inappropriate, and the control device 21 controls the operation of the work machine 1 based on the remote control signal that is determined to be appropriate by the signal receiving units 41a, 21a.

[0137] According to the above configuration, even if a communication delay occurs during remote control of the work machine 1 by the remote control terminal 30, the signal receiving units 41a and 21a receive the remote control signal and determine whether the remote control signal is appropriate based on the second timestamp of the remote control signal and the first timestamp of the monitoring data stored in the storage devices 42 and 22. The signal receiving units 41a and 21a then invalidate the remote control signal determined to be inappropriate. This prevents the work machine 1 from operating in an inappropriate manner based on a communication delay. Furthermore, even if an obstacle (object) not indicated in the monitoring data displayed on the remote control terminal 30 actually appears around the work machine 1, the invalid remote control signal due to the communication delay prevents the work machine 1 from colliding with the obstacle by operating based on the remote control signal. This makes it possible to hedge risks even when a communication delay occurs during remote control of the work machine 1. Furthermore, the control device 21 controls the operation of the work machine 1 based on the remote control signal that the signal receiving units 41a, 21a determine to be appropriate, so that the work machine 1 can be operated effectively and stably.

[0138] In this embodiment, the signal receiving unit 41a, 21a acquires from the storage devices 42, 22 specific monitoring data assigned a first timestamp indicating a first time that is the same as the second time indicated by the second timestamp assigned to the received remote control signal, or a first time that is earlier than the second time and closest to the second time, and the latest monitoring data, and detects the difference between the specific monitoring data and the latest monitoring data.If the difference does not exceed a predetermined level, the signal receiving unit 41a, 21a determines that the received remote control signal is appropriate, transfers the remote control signal to the control device 21, and allows the control device 21 to control the operation of the work machine 1 based on the remote control signal.If the difference exceeds a predetermined level, the signal receiving unit 41a, 21a determines that the received remote control signal is inappropriate, invalidates the remote control signal, and prevents the control device 21 from controlling the operation of the work machine 1 based on the remote control signal.

[0139] According to the above, when a communication delay occurs during remote control of the work machine 1 by the remote control terminal 30, and an obstacle (object) that was not shown in the specific monitoring data equivalent to the monitoring data displayed on the remote control terminal 30 is shown in the latest monitoring data stored in the storage device 22, that is, when an obstacle is actually present around the work machine 1, the difference between the specific monitoring data equivalent to the monitoring data displayed on the remote control terminal 30 and the latest monitoring data exceeds a predetermined level. Then, the signal receiving units 41a, 21a determine that the received remote control signal is inappropriate and invalidate the remote control signal, so that the work machine 1 (or work device 2) can avoid colliding with an obstacle by operating (for example, starting to travel or work) based on the remote control signal. Furthermore, even when the conditions around the work machine indicated by the latest monitoring data change significantly compared to the conditions around the work machine indicated by specific monitoring data, the difference between the specific monitoring data and the latest monitoring data exceeds a predetermined level, and the remote control signal received by the signal receiving units 41a, 21a is invalidated, thereby preventing the work machine 1 from operating unnecessarily based on the remote control signal.

[0140] Furthermore, in this embodiment, the first assigning unit 21d assigns a first timestamp indicating the current time to the monitoring data every time the first assigning unit 21d acquires monitoring data from the monitoring device 25. This allows all monitoring data output from the monitoring device 25 to be managed using the first timestamp including unique time information.

[0141] In this embodiment, when a remote control signal is transmitted from the remote control terminal 30, the second assigning unit 31d assigns a second timestamp indicating the current time to the remote control signal. This allows all remote control signals transmitted from the remote control terminal 30 to be managed using the second timestamp including unique time information. Furthermore, monitoring data to which a first timestamp equivalent to the transmission time of the remote control signal has been assigned can be easily read from the storage devices 42 and 22.

[0142] Furthermore, in this embodiment, the remote control terminal 30 has a display unit (display / operation unit) 34 and can acquire the latest monitoring data from the storage devices 42, 22 and display the monitoring results indicated by the monitoring data on the display unit 34. The second assigning unit 31d refers to the first timestamp assigned to the monitoring data indicating the monitoring results displayed on the display unit 34 when the remote control terminal 30 is operated, and assigns a second timestamp indicating a second time that is identical to the first time indicated by the first timestamp to the remote control signal. This makes it possible to manage all remote control signals transmitted from the remote control terminal 30 using the second timestamp including time information. Furthermore, when the operator 60 operates the remote control terminal 30, the signal receiving unit 41a, 21a can reliably acquire specific monitoring data corresponding to the monitoring data displayed on the display unit 34 from the storage devices 42, 22.

[0143] Furthermore, in this embodiment, when the signal receiving units 41a, 21a determine that the received remote control signal is appropriate, they validate the remote control signal by transferring it to the control device 21, and when they determine that the received remote control signal is inappropriate, they invalidate the remote control signal by discarding it without transferring it to the control device 21. This allows the control device 21 to control the operation of the work machine 1 based on an appropriate remote control signal, even if a communication delay occurs when the work machine 1 is remotely controlled by the remote control terminal 30. It also makes it possible to reliably prevent the control device 21 from controlling the operation of the work machine 1 based on an inappropriate remote control signal.

[0144] Furthermore, in this embodiment, the signal receiving units 41a, 21a notify the remote control terminal 30 that the remote operation signal has been invalidated, and the remote control terminal 30 has a display unit (display operation unit) 34, and upon receiving a notification from the signal receiving units 41a, 21a, displays the contents of the notification on the display unit 34. This allows the operator 60 to easily understand by looking at the display unit 34 of the remote control terminal 30 that the remote operation signal corresponding to the input operation instruction for the work machine 1 has been invalidated and that the operation has not been executed by the work machine 1.

[0145] Furthermore, in this embodiment, the remote control terminal 30 has an operation unit (display operation unit) 34 operated by the operator 60, generates a remote operation signal corresponding to an operation instruction for the work machine 1 input by operating the operation unit 34, and the signal receiving units 41a, 21a judge the appropriateness of the remote operation signal based on the operation instruction corresponding to the received remote operation signal. As a result, the signal receiving units 41a, 21a do not judge the appropriateness of all received remote operation signals, thereby reducing the processing load on the signal receiving units 41a, 21a and enabling the control device 21 to quickly execute operation control of the work machine 1 based on a remote operation signal corresponding to a specific operation instruction.

[0146] Furthermore, in this embodiment, the remote control terminal 30 has an operation unit (display operation unit) 34 operated by the operator 60, and generates a remote control signal corresponding to an operation instruction for the work machine 1 input by operating the operation unit 34. The signal receiving units 41a, 21a determine the appropriateness of the remote control signal when the operation instruction corresponding to the received remote control signal is an operation instruction related to the travel of the work machine 1 or an operation performed by the work device 2 connected to the work machine 1. As a result, for remote control signals corresponding to operation instructions related to the travel or operation of the work machine 1 that involve a risk due to communication delays, the signal receiving units 41a, 21a determine the appropriateness and validate or invalidate the signals, thereby hedging against the risk. Furthermore, for remote control signals corresponding to other operation instructions for the work machine 1 that do not involve a risk due to communication delays, the signal receiving units 41a, 21a do not determine the appropriateness. This reduces the processing load of the signal receiving units 41a, 21a, and allows the control device 21 to quickly control the operation of the work machine 1 based on the remote control signal.

[0147] 1A to 8, the present embodiment includes a communication device (wireless communication device) 23 that is provided in the work machine 1 and that communicates wirelessly, and an assistance device 40 that is provided outside the work machine 1 and outside the remote control terminal 30, the remote control terminal 30 having a first communication unit (communication unit) 33 that performs communication, the assistance device 40 having a second communication unit (communication unit) 43 that communicates with the communication device 23 and the first communication unit 33, the monitoring device 25 and the first assigning unit 21d are provided in the work machine 1, the second assigning unit 31d is provided in the remote control terminal 30, and the storage device 42 and signal receiving unit 41a are provided in the assistance device 40. As a result, a first timestamp can be assigned to monitoring data output from the monitoring device 25 of the work machine 1, and then the monitoring data can be saved in the storage device 42 of the assistance device 40. In addition, the signal receiving unit 41a of the support device 40 can receive a remote control signal from the remote control terminal 30, determine whether the remote control signal is appropriate, and then send an appropriate remote control signal to the control device 21 of the work machine 1, thereby disabling the inappropriate remote control signal.

[0148] 9 to 11, the system includes a communication device (wireless communication device) 23 that is provided in the work machine 1 and that communicates wirelessly, and an assistance device 40 that is provided outside the work machine 1 and outside the remote control terminal 30, the remote control terminal 30 having a first communication unit (communication unit) 33 that performs communication, the assistance device 40 having a second communication unit 43 that communicates with the communication device 23 and the first communication unit 33, the monitoring device 25 and the first assigning unit 21d are provided in the work machine 1, the second assigning unit 31d is provided in the remote control terminal 30, and the storage devices 22, 42 and signal receiving units 21a, 41a are provided in the work machine 1 or the assistance device 40. As a result, a first timestamp can be assigned to monitoring data output from the monitoring device 25 of the work machine 1, and then the monitoring data can be saved in the storage device 42 of the assistance device 40 or the storage device 22 of the work machine 1. In addition, the signal receiving unit 41a of the support device 40 or the signal receiving unit 21a of the work machine 1 can receive a remote control signal from the remote control terminal 30, determine whether the remote control signal is appropriate, and then send an appropriate remote control signal to the control device 21, thereby disabling the inappropriate remote control signal.

[0149] 9 to 11, the communication device 23 communicates wirelessly via a mobile phone communication network 51, a wide area network (Internet) 50, or a local area network (LAN) 53, and the first communication unit 33 and the second communication unit 43 communicate wirelessly or by wire via the mobile phone communication network 51, a fixed telephone communication network 52, the wide area network 50, or the local area network 53. As a result, even if a communication delay occurs between the communication device 23 of the work machine 1, the support device 40, and the remote control terminal 30 due to a communication failure in the mobile phone communication network 51, the fixed telephone communication network 52, the wide area network 50, or the local area network 53 during remote control of the work machine 1, it is possible to hedge against the risk caused by this.

[0150] 12, the work machine 1 is provided with a communication device (wireless communication device) 23 that communicates wirelessly. The remote control terminal 30 has a first communication unit 33 that communicates. The monitoring device 25, the first assigning unit 21d, the storage device 22, and the signal receiving unit 21a are provided in the work machine 1. The second assigning unit 31d is provided in the remote control terminal 30. This allows a first timestamp to be assigned to monitoring data output from the monitoring device 25 of the work machine 1, and then the monitoring data is stored in the storage device 22. The signal receiving unit 21a of the work machine 1 receives a remote control signal from the remote control terminal 30, determines whether the remote control signal is appropriate, and promptly controls the operation of the work machine 1 using the control device 21 based on the appropriate remote control signal. The signal receiving unit 21a can invalidate an inappropriate remote control signal, thereby avoiding risks resulting from the inappropriate remote control signal.

[0151] 12, the communication device (wireless communication device) 23 communicates wirelessly via the mobile phone communication network 51, the wide area network 50, or the narrow area network 53, and the first communication unit 33 communicates wirelessly or by wire via the mobile phone communication network 51, the fixed telephone communication network 52, the wide area network 50, or the narrow area network 53. As a result, even if a communication delay occurs between the communication device 23 of the work machine 1 and the remote control terminal 30 due to a communication failure in the mobile phone communication network 51, the fixed telephone communication network 52, the wide area network 50, or the narrow area network 53 when the work machine 1 is remotely controlled, it is possible to hedge against the risk caused by this.

[0152] In this embodiment, the wide area network 50 is configured from the Internet, and the narrow area network 53 is configured from a local area network. As a result, even if a communication delay occurs between the communication device 23 of the work machine 1, the support device 40, or the remote control terminal 30 due to a communication problem on the Internet or the local area network when the work machine 1 is remotely controlled, it is possible to hedge against the risk caused by this.

[0153] Furthermore, in this embodiment, the work implement 1 is an agricultural machine that performs agricultural work in a field, and the monitoring device 25 is provided on the agricultural machine and includes a camera 25c or sensors 25a and 25b that detect objects around the agricultural machine. The monitoring data includes image data of the area around the agricultural machine captured by the camera 25c or detection data indicating the detection results of the sensors. This allows the camera 25c or sensors 25a and 25b to monitor the conditions around the work implement 1 that is an agricultural machine or the objects in the area, and the monitoring results can be displayed on the remote control terminal 30. This makes it easier for the operator 60 operating the remote control terminal 30 to grasp the conditions around the work implement 1 and to remotely control the work implement 1. Furthermore, even if communication delays occur during remote control of the work implement 1 that is an agricultural machine, risk hedging can be performed.

[0154] Although the present invention has been described above, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0155] 1. Work equipment (agricultural machinery) 2. Work equipment 21 Control device 21a, 41a Signal reception section 21d First Grant 22, 42 Storage device 23 Wireless communication equipment (communication equipment) 25 Monitoring equipment 25a Laser sensor (sensor) 25b Ultrasonic sensor (sensor) 25c camera 30 Remote Control Terminal 31d Second Grant 33 Communications Department (First Communications Department) 34 Display and operation section (display section, operation section) 38 Display section 40 Support equipment 43 Communications Department (Second Communications Department) 50 Internet (wide area network) 51 Mobile phone network 52 Fixed telephone communication network 53 LAN (Narrow Area Network) 60 Operator 100 Work machine remote control system

Claims

1. a monitoring device that monitors the periphery of the travellable work machine and outputs monitoring data indicative of the monitoring results; a first timestamp assigning unit that assigns a first timestamp to the monitoring data; a storage device capable of storing a plurality of pieces of the monitoring data together with the first timestamps assigned to the monitoring data; a remote control terminal that receives the monitoring data, is capable of displaying the monitoring results indicated by the monitoring data, and is operated to transmit a remote operation signal for remotely operating the work machine; a second time stamp assigning unit that assigns a second time stamp to the remote control signal when the remote control signal is transmitted from the remote control terminal; a signal receiving unit that receives the remote control signal transmitted from the remote control terminal, determines whether the remote control signal is appropriate based on the second timestamp added to the received remote control signal and the first timestamp added to the monitoring data stored in the storage device, and invalidates the remote control signal that is determined to be inappropriate; a control device that controls the operation of the work machine based on the remote control signal determined to be appropriate by the signal receiving unit, The signal receiving unit acquiring, from the storage device, specific monitoring data to which the first timestamp indicating a first time that is the same as the second time indicated by the second timestamp added to the received remote control signal or a first time that is earlier than the second time and closest to the second time, and latest monitoring data, and detecting a difference between the specific monitoring data and the latest monitoring data; If the difference does not exceed a predetermined level, the received remote control signal is determined to be appropriate, the remote control signal is transferred to the control device, and the control device is allowed to control the operation of the work machine based on the remote control signal. If the difference exceeds a predetermined level, the remote control system determines that the received remote control signal is inappropriate, invalidates the remote control signal, and prevents the control device from controlling the operation of the work machine based on the remote control signal.

2. The remote control system for a work machine according to claim 1 , wherein the first timestamp assigning unit assigns the first timestamp indicating a current time to the monitoring data every time the monitoring data is acquired from the monitoring device.

3. The remote control system for a work machine according to claim 1 , wherein the second timestamp assigning unit assigns the second timestamp indicating a current time to the remote control signal when the remote control signal is transmitted from the remote control terminal.

4. the remote control terminal has a display unit, and is capable of acquiring the latest monitoring data from the storage device and displaying the monitoring results indicated by the monitoring data on the display unit; 2. The remote control system for a work machine according to claim 1, wherein the second assigning unit refers to the first timestamp assigned to the monitoring data indicating the monitoring result that was displayed on the display unit when the remote control terminal was operated, and assigns the second timestamp indicating a second time that is the same as the first time indicated by the first timestamp to the remote control signal.

5. The signal receiving unit If the received remote control signal is determined to be appropriate, the remote control signal is validated by transferring the remote control signal to the control device; 2. The remote control system for a work machine according to claim 1, wherein, if the received remote control signal is determined to be inappropriate, the remote control signal is invalidated by being discarded without being transferred to the control device.

6. the signal receiving unit notifies the remote control terminal that the remote operation signal has been invalidated; The remote control system for a work machine according to claim 1, wherein the remote control terminal has a display unit, and upon receiving the notification from the signal receiving unit, causes the content of the notification to be displayed on the display unit.

7. the remote control terminal has an operation unit operated by an operator, and generates the remote operation signal in accordance with an operation instruction of the work machine input by operating the operation unit; The remote control system for a work machine according to claim 1 , wherein the signal receiving unit determines whether the remote control signal is appropriate based on the operation instruction corresponding to the received remote control signal.

8. the remote control terminal has an operation unit operated by an operator, and generates the remote operation signal in accordance with an operation instruction of the work machine input by operating the operation unit; 2. The remote control system for a work machine according to claim 1, wherein the signal receiving unit determines whether the remote control signal is appropriate when the operation instruction corresponding to the received remote control signal is an operation instruction related to the travel of the work machine or work performed by a work device connected to the work machine.

9. a communication device provided in the work machine and performing wireless communication; a support device provided other than the work machine and other than the remote control terminal, the remote control terminal has a first communication unit for performing communication; the support device has a second communication unit that communicates with the communication device and the first communication unit, The monitoring device and the first applying unit are provided in the work machine, the second providing unit is provided in the remote control terminal, The remote control system for a work machine according to claim 1 , wherein the storage device and the signal receiving unit are provided in the support device.

10. a communication device provided in the work machine and performing wireless communication; a support device provided other than the work machine and other than the remote control terminal, the remote control terminal has a first communication unit for performing communication; the support device has a second communication unit that communicates with the communication device and the first communication unit, The monitoring device and the first applying unit are provided in the work machine, the second providing unit is provided in the remote control terminal, The remote control system for a work machine according to claim 1 , wherein the storage device and the signal receiving unit are provided in the work machine or the support device.

11. the communication device communicates wirelessly via a mobile phone network, a wide area network, or a short area network; The remote control system for a work machine according to claim 9 or 10, wherein the first communication unit and the second communication unit communicate wirelessly or wired via a mobile phone communication network, a fixed telephone communication network, a wide area network, or a narrow area network.

12. a communication device provided in the work machine and performing wireless communication; the remote control terminal has a first communication unit for performing communication; the monitoring device, the first providing unit, the storage device, and the signal receiving unit are provided in the work machine, The remote control system for a work machine according to claim 1 , wherein the second providing unit is provided in the remote control terminal.

13. the communication device communicates wirelessly via a mobile phone network, a wide area network, or a short area network; The remote control system for a work machine according to claim 12, wherein the first communication unit communicates wirelessly or via a wired connection via a mobile phone communication network, a fixed telephone communication network, a wide area network, or a narrow area network.

14. the wide area network comprises the Internet; 12. The remote control system for a work machine according to claim 11, wherein the narrow area network is configured as a local area network.

15. The work machine is composed of an agricultural machine that performs agricultural work in a field, the monitoring device is provided on the agricultural machine and has a camera or a sensor that detects objects in the vicinity of the agricultural machine; 2. The remote control system for a work machine according to claim 1, wherein the monitoring data includes image data of the surroundings of the agricultural machine captured by the camera or detection data indicating the detection results of the sensor.

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