Remote operation system

Abstract

The present invention enables a remote operator to cause a remote work machine (1) to travel in a stable manner.　A remote operation system (100) comprises a machine body (3), a work device (2) that is supported by the machine body (3), a remote work machine (1) that has a traveling device (7) which supports the machine body (3) so as to be capable of traveling, and a remote operation device (35) that receives operation and remotely operates the remote work machine (1). In the remote operation, the traveling device (7) causes the machine body (3) to travel at or below a limit vehicle speed corresponding to a steering angle. Moreover, in the remote operation, the traveling device (7) causes the machine body (3) to travel at or below the limit vehicle speed, said limit vehicle speed decreasing as the steering angle increases.

Description

Remote Control System

[0001] The present invention relates to a remote control system for remotely controlling a remote-controlled working machine.

[0002] 2. Description of the Related Art Conventionally, remote control systems for remotely operating work vehicles have been known (see, for example, Patent Document 1).

[0003] Japanese Patent Publication No. 2021-36796

[0004] However, remote control, in which a remote operator controls a work machine (work vehicle) from a location away from the machine, and manual control, in which a driver actually rides on the work machine, differ in the traveling speed experienced by the operator, so remote control must be performed in a different way from manual control.

[0005] The present invention has been made to solve the problems of the prior art, and has as its object to provide a remote control system that allows a remote operator to stably drive a remote-controlled working machine.

[0006] A remote control system according to one aspect of the present invention comprises a remote work machine having a vehicle body, a work device supported on the vehicle body, a traveling device that supports the vehicle body so that it can move, and a remote control device that receives operations and remotely controls the remote work machine, wherein the traveling device causes the vehicle to move at or below a speed limit that corresponds to a steering angle during remote control.

[0007] The traveling device may, during the remote control, cause the vehicle to travel at or below the speed limit, which decreases as the steering angle increases.

[0008] The remote-controlled work machine may have a coupling device that detachably couples the work device to the vehicle body, and the traveling device may cause the vehicle body to travel at or below the speed limit that corresponds to the work device coupled to the coupling device.

[0009] The traveling device may cause the machine body to travel at or below the limited vehicle speed, which is lower when the working device is connected to the coupling device than when the working device is not connected to the coupling device.

[0010] The remote control system may include a first detection device that detects the attitude of the remote work machine, and the traveling device may cause the vehicle to travel at or below the speed limit, which becomes lower as the attitude of the remote work machine detected by the first detection device becomes more inclined relative to the horizontal state.

[0011] The remote control system may include a second detection device that detects the gradient of the surrounding area of ​​the remote work vehicle, and the traveling device may cause the vehicle to travel at or below the speed limit, which decreases as the gradient of the surrounding area detected by the second detection device increases.

[0012] The second detection device may be a sensing device that senses the surroundings of the remote-controlled work machine and detects the gradient of the surroundings of the remote-controlled work machine.

[0013] The second detection device may detect the gradient around the remote work machine based on a position detection device that detects the position of the remote work machine, the position of the remote work machine detected by the position detection device, and map information indicating the gradient stored in a memory device.

[0014] In addition to being remotely controlled by the remote control device, the remote work machine is capable of autonomous driving and / or manual driving operated by a driver on board the remote work machine, and the driving device may cause the vehicle to drive at or below the limited vehicle speed, which is lower when remotely controlled than when the remote work machine is driving automatically or manually.

[0015] According to the present invention, a remote operator can drive a remote-controlled working machine stably.

[0016] 1 is a configuration diagram of a remote control system according to an embodiment of the present invention; FIG. 1 is a side view of a tractor, which is an example of a remote work machine; FIG. 2 is a diagram showing an example of a forward / backward tilt state of the remote work machine; FIG. 3 is a diagram showing an example of a left / right tilt state of the remote work machine; FIG. 4 is a diagram showing an example of the state of the gradient around the remote work machine; FIG. 5 is a diagram showing an example of correspondence data; FIG. 6 is a diagram showing an example of a display screen of a display device; FIG. 7 is a diagram showing an example of a vehicle speed limit map; FIG. 8 is a diagram showing an example of a vehicle speed limit map based on the attachment of a work machine; FIG. 9 is a diagram showing an example of a vehicle speed limit map based on the attitude of the remote work machine; FIG. 10 is a diagram showing an example of a vehicle speed limit map based on the gradient around the remote work machine; FIG. 11 is a diagram showing an example of a vehicle speed limit map of the remote work machine during automatic or manual driving; FIG. 12 is a flowchart showing the operation of the remote work machine and a remote device; FIG. 13 is a flowchart showing the operation of the remote work machine and a remote device in a modified example;

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0018] FIG. 1 is a configuration diagram of a remotely controlled system 100 according to one embodiment of the present invention. The remotely controlled system 100 includes a remotely controlled work machine 1 and a remote device 30. The remotely controlled system 100 and the remote device 30 enable remote control (or remote operation) and remote monitoring of the remotely controlled work machine 1. The remotely controlled work machine 1 is a farm machine (also referred to as a "remotely controlled agricultural machine") that can be remotely operated (e.g., remotely traveled and remotely operated) using the remote device 30. The remotely controlled work machine 1 includes agricultural machinery such as tractors, rice transplanters, and combine harvesters that are equipped with (supports) a work device 2 such as an implement. In this embodiment, in addition to being remotely controlled using the remote device 30, the remotely controlled work machine 1 can also be manually operated (manually steered, manually traveled) by a driver (worker, operator) aboard the remotely controlled work machine 1.

[0019] FIG. 2 is a side view of a tractor, an example of the remote-controlled work machine 1. Hereinafter, the front side of a driver seated in the driver's seat 10 of the remote-controlled work machine 1 (in the direction of arrow A1 in FIG. 2 ) will be referred to as the front, the rear side of the driver (in the direction of arrow A2 in FIG. 2 ) will be referred to as the rear, the left side of the driver will be referred to as the left side (the near side in FIG. 2 ), and the right side of the driver will be referred to as the right side (the far side in FIG. 2 ). The upper side of the driver will be referred to as the upside (in the direction of arrow Z1 in FIG. 2 ), and the lower side of the driver will be referred to as the downside (in the direction of arrow Z2 in FIG. 2 ). The horizontal direction, which is perpendicular to the fore-and-aft direction of the remote-controlled work machine 1, will be referred to as the width direction. The remote-controlled work machine 1 includes a body 3. The body 3 is provided with a traveling device 7. The traveling device 7 has front wheels 7F and rear wheels 7R on both the left and right sides of the body 3, respectively, to support the body 3 so that it can travel. The traveling device 7 may be a crawler-type device.

[0020] 1 and 2, the aircraft body 3 is equipped with a prime mover 4, a transmission 5, a braking device 13, and a steering device 14. The prime mover 4 is formed of an engine (diesel engine, gasoline engine), an electric motor, or the like.

[0021] The transmission 5, for example, 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. The braking device 13 controls the movement of the machine body 3. The steering device 14 is operated to direct the machine body 3 in a predetermined direction.

[0022] A control device 11 for manually operating the remote-controlled work machine 1 is provided around the driver's seat 10. The remote-controlled work machine 1 is a tractor that can travel and work unmanned, but a driver seated in the driver's seat 10 can operate the control device 11 to travel the remote-controlled work machine 1 and perform work using the work device 2. The control device 11 includes a steering wheel 11a, an accelerator pedal 11b, a brake pedal, a gear shift lever, and the like.

[0023] A coupling device 8 is provided at the rear of the machine body 3. The coupling device 8 allows the working device 2 to be detachably coupled to the machine body 3. The coupling device 8 is configured with a three-point link mechanism or the like. By coupling the working device 2 to the coupling device 8 and traveling using the traveling device 7, the remote-controlled work machine 1 (machine body 3) can raise and lower the working device 2 and change its attitude.

[0024] The work devices 2 include, for example, a tilling device for tilling the soil, a fertilizer spreading device for spreading fertilizer, a pesticide spreading device for spreading pesticides, a harvesting device for harvesting, a reaping device for reaping grass etc., a spreading device for spreading grass etc., a grass collecting device for collecting grass etc., a shaping device for shaping grass etc. The remote-controlled work machine 1 performs agricultural work in the field using these work devices 2.

[0025] 1 , the remote-operated work machine 1 includes an on-board control device 21, a storage device 22, a second communication device (on-board communication device) 23, a position detection device 24, a first detection device (inertial measurement unit) 25, a second detection device (sensing device) 26, a state detection device 27, and a third detection device 28. In addition, an on-board network such as CAN, LIN, or FlexRay is configured in the remote-operated work machine 1, and the on-board control device 21 is electrically connected to the storage device 22, the second communication device 23, the position detection device 24, etc.

[0026] The on-board control device 21 is composed of an ECU (electronic control unit) including a processor 21a and a memory 21b. The on-board control device 21 is a controller that controls the operation of each part of the remote-controlled work machine 1. The on-board control device 21 controls a group of actuators including electric or hydraulic motors, cylinders, control valves, etc. for operating each part of the remote-controlled work machine 1, such as the prime mover 4, transmission 5, travel device 7, braking device 13, and coupling device 8. The on-board control device 21 controls the group of actuators according to a manual mode in which the driver manually controls the remote work machine 1 and a remote mode in which a remote operator remotely controls the remote work machine 1. Note that switching between these modes is performed using a mode selector switch included in the control device 11 or the remote control device 35 described below. The memory 21b is composed of volatile or non-volatile memory, etc. Various information and data used by the on-board control device 21 to control the operation of each part of the remote-controlled work machine 1 are readably and writably stored in the memory 21b of the on-board control device 21.

[0027] The storage device 22 is, for example, an SSD (Solid State Drive), an HDD (Hard Disk Drive), etc. The storage device 22 stores various types of information and data that the on-board control device 21 uses to control the operation of each part of the remote-controlled work machine 1 in a readable and writable manner.

[0028] The second communication device 23 is composed of an antenna, an IC (integrated circuit), an electric circuit, etc. for wireless communication via a mobile phone communication network, the Internet, or a wireless LAN. The on-board control device 21 communicates wirelessly with the remote device 30 via the second communication device 23. The on-board control device 21 also has an RTC (real-time clock) and can measure the date and time.

[0029] Although the present embodiment illustrates an example in which the remote work machine 1 and the remote device 30 communicate via a mobile phone communication network or the like, the remote work machine 1 and the remote device 30 may alternatively communicate via a mobile phone communication network or an external device such as a server or a repeater. Alternatively, the remote work machine 1 and the remote device 30 may communicate directly using short-range wireless signals such as Bluetooth (registered trademark) Low Energy (BLE) signals or Ultra High Frequency (UHF) signals. In this case, it is sufficient that the second communication device 23 and the remote device 30 each have an interface for short-range wireless communication.

[0030] 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 (such as the position of the positioning satellite, the transmission time, and correction information) and detects its own position based on the signals. The position detection device 24 may detect its own position as a position corrected based on signals such as corrections from a base station (reference station) that can receive signals from the positioning satellites. The position detection device 24 may also calculate the position of the remote-controlled work machine 1 based on its detected position and pre-stored external shape information of the remote-controlled work machine 1. The position detection device 24 may also calculate the position of the work machine 2 based on its detected position, pre-stored external shape information of the work machine 2, and the mounting position of the work machine 2 relative to the machine body 3.

[0031] The first detection device 25 includes a gyro sensor or an acceleration sensor, and detects the roll angle, pitch angle, yaw angle, etc. of the remote-controlled work machine 1 (machine body 3). That is, the first detection device 25 detects the tilt attitude of the remote-controlled work machine 1 to the left and right and forward and backward relative to the horizontal state.

[0032] 3A is a diagram showing an example of a forward-to-rear tilt state of the remote-controlled work machine 1 when viewed from the side. As shown in FIG. 3A , when the body 3 of the remote-controlled work machine 1 is in a forward-leaning position with the front tilted downward, the pitch angle θp of the body 3 detected by the first detector 25 is a negative value (θp<0). On the other hand, when the body 3 is in a backward-leaning position with the rear tilted downward, the pitch angle θp of the body 3 detected by the first detector 25 is a positive value (θp>0). Note that when the body 3 is in a horizontal position, the pitch angle θp of the body 3 detected by the first detector 25 is zero (θp=0).

[0033] 3B is a diagram showing an example of a state in which the remote-controlled work machine 1 is tilted to the left or right when viewed from behind. When the body 3 of the remote-controlled work machine 1 is in a right-leaning position, tilted downward to the right, as shown in FIG. 3B , the roll angle θr of the body 3 detected by the first detector 25 is a negative value (θr<0). On the other hand, when the body 3 is in a left-leaning position, tilted downward to the left, the roll angle θr of the body 3 detected by the first detector 25 is a positive value (θr>0). When the body 3 is in a horizontal position, the roll angle θr of the body 3 detected by the first detector 25 is zero (θr=0).

[0034] As described above, when the attitude of the remote-controlled work machine 1 is horizontal, the absolute values ​​of the pitch angle θp and roll angle θr detected by the first detection device 25 are approximately equal to zero. When the attitude of the remote-controlled work machine 1 is tilted relative to the horizontal, the absolute values ​​of the pitch angle θp and roll angle θr detected by the first detection device 25 become larger (FIGS. 3A and 3B).

[0035] The second detection device 26 is a sensing device that senses (monitors) the surroundings of the remote-controlled work machine 1. The second detection device 26 includes a laser sensor 26a, an ultrasonic sensor 26b, a camera 26c, and an object detection unit 26d. In this embodiment, the second detection device 26 includes a plurality of laser sensors 26a and ultrasonic sensors 26b. The plurality of laser sensors 26a and the plurality of ultrasonic sensors 26b are installed at predetermined locations, such as the front, rear, and left and right sides of the remote-controlled work machine 1, and detect surrounding conditions, such as the front, rear, left and right sides of the remote-controlled work machine 1, and objects in the surroundings. For example, the laser sensor 26a and the ultrasonic sensor 26b are installed at predetermined positions on the machine body 3 that can detect objects within a predetermined target detection distance from the remote-controlled work machine 1 and that are located lower than the machine body 3.

[0036] The laser sensor 26a and the ultrasonic sensor 26b are examples of object sensors. Note that at least one of the laser sensor 26a and the ultrasonic sensor 26b may be provided in plurality as an object sensor in the second detection device 26. Furthermore, the second detection device 26 may be provided with a plurality of other object sensors.

[0037] The laser sensor 26a is composed of an optical sensor such as a LiDAR (Light Detection and Ranging) sensor. The laser sensor 26a 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 26a then receives the measurement light reflected by the target object with a light-receiving element.

[0038] The object detection unit 26d is composed of an electric circuit or an IC that detects the presence, position, and type of an object based on the light-receiving signal output from the light-receiving element of the laser sensor 26a. The object detection unit 26d detects the distance to the object based on the time between when the laser sensor 26a emits measurement light and when it receives the reflected light (TOF (Time of Flight) method). Objects detected by the object detection unit 26d include the field in which the remote-controlled work machine 1 travels and works, crops in the field, the ground, the slope of the ground, other objects, people, etc.

[0039] The ultrasonic sensor 26b is composed of an airborne ultrasonic sensor such as a sonar. The ultrasonic sensor 26b 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 26d detects the presence or absence, position, and type of object based on the signal output from the receiver of the ultrasonic sensor 26b. The object detection unit 26d also detects the distance to the object based on the time between when the ultrasonic sensor 26b transmits the measurement wave and when it receives the reflected wave (TOF method).

[0040] The camera 26c is composed of a CCD camera equipped with a CCD (Charge Coupled Device) image sensor, or a CMOS camera equipped with a CMOS (Complementary Metal Oxide Semiconductor) image sensor. As shown in Fig. 2, the cameras 26c are installed at predetermined locations such as the front, rear, left and right sides of the remote-controlled work machine 1 and inside the cabin 9, and capture images of the surroundings such as the front, rear, left and right sides of the remote-controlled work machine 1 and output data of the captured images. The camera 26c is an example of an imaging device.

[0041] 2, for example, camera 26c1 installed inside cabin 9 captures an image of the area in front of the remote-controlled work machine 1 from the driver's seat 10. More specifically, camera 26c1 captures an image of the area in front of the remote-controlled work machine 1 (in the direction of travel, A1 direction) from a field of view that is substantially the same as that of a driver seated in the driver's seat 10. In other words, camera 26c1 can obtain an image of the area in the direction of travel of the remote-controlled work machine 1.

[0042] 2, the camera 26c2 installed at the rear of the body 3 of the remote-controlled work machine 1 captures images behind the remote-controlled work machine 1. More specifically, the camera 26c2 captures images in the direction opposite to the field of view of the driver seated in the driver's seat 10 (direction A2). In other words, the camera 26c2 can obtain captured images of the direction opposite to the traveling direction of the remote-controlled work machine 1.

[0043] The object detection unit 26d can also detect the presence or absence of an object, the position of the object, the type of the object, and the like, based on the captured image data output from the camera 26c.

[0044] In the above example, the first detection device 25 of the remote-controlled work machine 1 detects the tilted attitude of the remote-controlled work machine 1. However, instead of or in addition to this, the second detection device 26 may be able to calculate the gradient of the surroundings of the remote-controlled work machine 1 based on signals output from the laser sensor 26a, ultrasonic sensor 26b, camera 26C, etc. For example, the second detection device 26 (object detection unit 26d) calculates a gradient value N that indicates the gradient of the surroundings of the remote-controlled work machine 1.

[0045] 3C is a diagram showing an example of the gradient state around the remote-controlled work vehicle 1. As shown in C1 and C2, the gradient value N detected by the second detection device 26 increases as the gradient of the surrounding area increases. For example, C1 shows the case where the gradient value N is n1%, and C2 shows the case where the gradient value N is n2%. The gradient value N is n2>n1, and the gradient (inclination) is greater in the case of C2 than in the case of C1.

[0046] The second detection device 26 senses the surrounding conditions of the remote-controlled work machine 1 and the work device 2 using the laser sensor 26a, ultrasonic sensor 26b, camera 26c, and object detection unit 26d, and outputs sensing information indicating the results to the on-board control device 21. The sensing information includes at least the detection information of the object detection unit 26d, the image data captured by the camera 26c, and the surrounding gradient, but the sensing information may also include detection information from the laser sensor 26a and ultrasonic sensor 26b.

[0047] The state detection device 27 detects the operating state of the remote-controlled work machine 1. Specifically, the state detection device 27 includes various sensors installed in each part of the remote-controlled work machine 1 (machine body 3) and a computing unit, and the computing unit detects (calculates) the operating state of the remote-controlled work machine 1 based on output signals from the various sensors. The state of the remote-controlled work machine 1 detected by the state detection device 27 includes the drive and stop states of each part of the remote-controlled work machine 1, the traveling direction, traveling speed, acceleration, and steering angle of the remote-controlled work machine 1, etc. In the following description, the steering angle is set to zero when the remote-controlled work machine 1 is traveling straight (when traveling straight), and will be described as the absolute value of the deviation from the steering angle when traveling straight, unless otherwise specified.

[0048] The state detection device 27 generates detection information indicating the detected operating state of the remote-controlled work machine 1 and outputs the detection information to the on-board control device 21. For example, the detection information of the state detection device 27 includes operation information of the remote-controlled work machine 1 and the work device 2. This operation information includes, for example, at least one piece of information among the speed (or acceleration) of the remote-controlled work machine 1, the gear shift position of the transmission 5, the braking position of the braking device 13, the operating position of the work device 2, and the steering angle of the machine body 3.

[0049] The third detection device 28 detects the state of the working device 2. The third detection device 28 includes various sensors installed in each part of the coupling device 8 and the working device 2, and a computing unit, and the computing unit detects (calculates) the operating state of the working device 2 based on output signals from the various sensors. The states of the working device 2 detected by the third detection device 28 include the type of working device 2, the attachment / detachment state of the working device 2, the drive / stop state of each part of the working device 2, the inclination of the working device 2, its height above ground, etc.

[0050] If the type of remote-controlled working machine 1 is a rice transplanter, the third detection device 28 may detect the drive and stop states of each mechanism related to seedling planting, the remaining amount of materials (seedlings, fertilizer), etc., based on output signals from various sensors arranged in each part of the seedling planting device, etc. If the type of remote-controlled working machine 1 is a combine harvester, the third detection device 28 may detect the drive and stop states of each mechanism related to harvesting, the characteristics of the harvested grain, etc., based on output signals from various sensors arranged in each part of the reaping device, grain tank, etc.

[0051] The position detection device 24, the first detection device 25, the state detection device 27, and the third detection device 28 output detection information indicating the results of detection at a predetermined cycle or at a predetermined timing to the on-board control device 21 as needed. The second detection device 26 also outputs sensing information indicating the results of sensing at a predetermined cycle or at a predetermined timing to the on-board control device 21 as needed. The on-board control device 21 stores the detection information and sensing information input from the position detection device 24, the state detection device 27, and the second detection device 26 in the internal memory 21b.

[0052] In addition, the on-board control device 21 sequentially transmits these detection information stored in the internal memory 21b and the sensing information of the second detection device 26 to the remote device 30 via the second communication device 23 at a predetermined period or at a predetermined timing in the case of remote driving.

[0053] The detection information and sensing information transmitted from the remote-controlled work machine 1 in this manner includes correspondence data (see FIG. 4 ) that associates the position information of the remote-controlled work machine 1 with captured images of the direction of travel of the remote-controlled work machine 1. FIG. 4 is a diagram showing an example of the correspondence data. That is, correspondence data that associates the detection information of the position detection device 24 (i.e., the position information of the remote-controlled work machine 1) with the sensing information of the second detection device 26 (e.g., images captured by the camera 26c1) is sequentially transmitted to the remote device 30. With regard to the captured images, as shown in FIG. 3 , correspondence data that associates the position information of the remote-controlled work machine 1 detected by the position detection device 24 (e.g., positions PU1, PV1, PW1, PX1) with the captured images captured by the camera 26c1 (e.g., captured images GPU1, GPV1, GPW1, GPX1) is sequentially transmitted to the remote device 30.

[0054] The on-vehicle control device 21 also communicates with a control unit 2a provided in the work device 2, and causes the control unit 2a to control the operation of the work device 2. That is, the on-vehicle control device 21 performs work on the field by controlling the operation of the work device 2 via the control unit 2a. For example, the control unit 2a is made up of a CPU, memory, etc. Note that some work devices 2 do not have a control unit 2a. In this case, the on-vehicle control device 21 controls the attitude of the work device 2 using the coupling device 8, and the work device 2 performs work on the field.

[0055] The on-board control device 21 controls the travel of the remotely operated work machine 1, the work performed by the work device 2, and other operations of the remotely operated work machine 1 based on detection information obtained from the first detection device 25, the second detection device 26, the state detection device 27, the third detection device 28, etc. Furthermore, when the on-board control device 21 receives a remote control signal transmitted from the remote device 30 via the second communication device 23, it controls the travel of the remotely operated work machine 1, the work performed by the work device 2, and other operations of the remotely operated work machine 1 based on the remote control signal in addition to the above information.

[0056] Furthermore, when controlling the travel of the remote-controlled work machine 1 or the work performed by the work device 2, the on-board control device 21 determines from the detection information of the object detection unit 26d whether or not an object is approaching the remote-controlled work machine 1 or the work device 2 within a predetermined distance and is likely to come into contact with the remote-controlled work machine 1 or the work device 2. If the on-board control device 21 determines that an object is approaching the remote-controlled work machine 1 or the work device 2 within a predetermined distance and is likely to come into contact with the remote-controlled work machine 1 or the work device 2, the on-board control device 21 controls the travel device 7 or the work device 2, etc., to automatically stop the travel or work of the remote-controlled work machine 1 and avoid contact with the object.

[0057] Next, the remote device 30 will be described. As shown in Fig. 1, the remote device 30 is located at a distance from the remote-controlled work machine 1. The remote device 30 allows the remote operator to remotely control the remote-controlled work machine 1 and monitor the state of the remote-controlled work machine 1 and the surrounding conditions of the remote-controlled work machine 1. The remote device 30 includes a control device 31, a storage device 32, a first communication device 33, a display device 34, a remote control device 35, and an input device 36.

[0058] The control device 31 is a processor that controls the operation of each part of the remote device 30. This processor functions as the control device 31, controlling the operation of each part of the remote device 30, for example, by executing a remote control program or application stored in the storage device 32. The control device 31 may be implemented by hardware such as an integrated circuit (IC chip), or by software using a computer. In the latter case, the computer includes a recording medium on which a program, which is software that implements each function of the control device 31, and various data related to the remote work machine 1 are recorded in a computer-readable manner, an arithmetic circuit such as a CPU (Central Processing Unit) that executes the instructions of the program, and a RAM (Random Access Memory) that expands the program and various data. The arithmetic circuit then reads and executes the program from the recording medium, thereby realizing the functions of the control device 31.

[0059] The internal memory 31 a provided in the control device 31 is a volatile or non-volatile memory. Various information and data used by the control device 31 to control the operation of each part of the remote device 30 are stored in the internal memory 31 a in a readable and writable manner.

[0060] The display control unit 31b provided in the control device 31 has a function of controlling the display screen displayed by the display device 34. For example, the display control unit 31b causes the display device 34 to display a display screen W1 ( FIG. 5 ) showing information related to remote driving.

[0061] The storage device 32 pre-stores applications such as a remote control program for remotely operating the remote work machine 1 and a remote monitoring program for remotely monitoring the remote work machine 1, as well as various data. The storage device 32 is, for example, an SSD (Solid State Drive) or an HDD (Hard Disk Drive).

[0062] The first communication device 33 is composed of an antenna, an IC, an electric circuit, etc. for wireless communication via a mobile phone communication network, the Internet, or a wireless LAN. The first communication device 33 is capable of wireless communication with the remote-controlled work machine 1 under the control of the control device 31. The first communication device 33 receives various data transmitted from the second communication device 23 (detection information from the position detection device 24, the first detection device 25, the state detection device 27, and the third detection device 28, sensing information from the second detection device 26, etc.). For example, the first communication device 33 receives correspondence data that associates the position information of the remote-controlled work machine 1 with an image captured of the direction in which the remote-controlled work machine 1 is traveling.

[0063] The display device 34 is, for example, a liquid crystal display, an organic EL display, or the like. The display device 34 displays various information for remotely operating the remote-controlled work machine 1. For example, the display device 34 displays a display screen W1 showing information related to remote operation based on an instruction signal from the display control unit 31b. FIG. 5 is a diagram showing an example of the display screen W1 of the display device 34. As shown in FIG. 5, the display screen W1 of the display device 34 displays images captured by the multiple cameras 26c.

[0064] The input device 36 is an interface for operating the remote device 30. The remote operator can input predetermined instructions to the remote device 30 by operating the input device 36. The input device 36 has sensors that detect the amount of operation, the speed of operation, the direction of operation, etc., and a driver that calculates (defines) an instruction signal for the remote device 30 based on the sensor detection results. The driver is a program stored in the memory device 32. When the remote operator operates the input device 36, the sensor of the input device 36 detects the amount of operation, etc., and inputs the detected information to the driver of the input device 36. The driver of the input device 36 defines the instruction signal based on the sensor detection results. Once the input device 36 defines the instruction signal, it inputs the instruction signal to the control device 31. The control device 31 controls the remote device 30 based on the instruction signal input by the input device 36.

[0065] The input device 36 may be a touch panel provided on the display device 34 so that touch operations on the display device 34 can be detected, or a hardware switch or the like may be used.

[0066] The remote control device 35 is a device for remotely controlling the remote-controlled work machine 1. The remote control device 35 includes a steering wheel 35a, an accelerator pedal 35b, a brake pedal 35c, and a gear shift lever 35d, which are arranged around the remote control seat. The remote control device 35 accepts operation by a remote operator. The remote operator sits in the remote control seat and operates the remote control device 35 to remotely control the travel of the remote-controlled work machine 1 or the work performed by the work device 2. The remote operator also monitors the remote-controlled work machine 1 and the surrounding conditions using the display device 34. The remote operator can also input predetermined information or instructions to the remote device 30 by operating the remote control device 35. The remote control device 35 may be a touchpad or a hardware switch, etc.

[0067] 1, the remote device 30 may be composed of a display terminal 70 and a remote control device 35. That is, the display terminal 70 may be a terminal device including a control device 31, a storage device 32, a first communication device 33, a display device 34, and an input device 36. The display terminal 70 may be, for example, a portable terminal device such as a tablet device or a smartphone, or a stationary computer installed in a base station.

[0068] When a remote operator operates the remote control device 35 to input an operation instruction for the remote-controlled work machine 1, the control device 31 generates a remote control signal corresponding to the operation instruction, and transmits the remote control signal to the remote-controlled work machine 1 via the first communication device 33. In other words, a remote control signal corresponding to operation of the steering wheel 35a, accelerator pedal 35b, brake pedal 35c, and gear shift lever 35d is transmitted to the remote-controlled work machine 1. When the on-board control device 21 of the remote-controlled work machine 1 receives the remote control signal from the remote device 30 via the second communication device 23, it operates each part of the remote-controlled work machine 1 based on the remote control signal, detection information from the position detection device 24, sensing information from the second detection device 26, and detection information from the state detection device 27, to control the traveling and steering of the remote-controlled work machine 1 and to control the work operation of the work device 2.

[0069] Furthermore, the on-board control device 21 periodically transmits detection information from the position detection device 24, the first detection device 25, the state detection device 27, and the third detection device 28, and sensing information from the second detection device 26, to the remote device 30 via the second communication device 23. When the control device 31 of the remote device 30 receives the detection information and sensing information via the first communication device 33, it stores the information in the internal memory 31a and displays it on the display device 34.

[0070] The traveling speed experienced by the operator differs between remote operation, in which the remote-controlled work machine 1 is operated from a location distant from the remote-controlled work machine 1, and manual operation (manual driving), in which the operator is on board and operates the remote-controlled work machine 1. For this reason, in order to ensure stable traveling of the remote-controlled work machine 1 during remote control, the on-board control device 21 controls the adjustment of the traveling speed of the traveling device 7.

[0071] During remote control, the traveling device 7 causes the machine body 3 to travel at or below a speed limit that corresponds to the steering angle. Specifically, the traveling device 7 causes the machine body 3 (remotely operated work machine 1) to travel at or below a speed limit that decreases as the steering angle increases. In other words, the traveling device 7 causes the machine body 3 to travel at or below a speed limit that increases as the steering angle decreases.

[0072] The storage device 22 of the remote-controlled work machine 1 stores a speed limit map M ( FIG. 6 ) that defines the correspondence between the steering angle and the speed limit, which is the upper limit of the vehicle speed (traveling speed) of the traveling device 7. The speed limit map M may be held as table-format data, or a software program that converts the steering angle into a function using the steering angle as an input argument may be stored in the storage device 22, and the on-board control device 21 in remote mode may acquire the speed limit by executing the software program.

[0073] FIG. 6 is a diagram showing an example of a vehicle speed limit map M. In FIG. 6 and FIGS. 7A to 7D described below, the vertical axis represents the vehicle speed limit, and the horizontal axis represents the steering angle. As shown in FIG. 6, in the vehicle speed limit map M, the vehicle speed limit decreases as the steering angle increases. In other words, the vehicle speed limit has a monotonically decreasing relationship with the steering angle. Note that the vehicle speed limit map M is curved, and the vehicle speed limit fluctuates relatively more when the steering angle is large than when the steering angle is small. However, it is sufficient that the vehicle speed limit decreases at least as the steering angle increases. The vehicle speed limit map M may also be substantially linear, and the vehicle speed limit and the steering angle are proportional to each other.

[0074] When the on-board control device 21 in remote mode receives a remote control signal from the remote device 30, it refers to the speed limit map M and obtains the speed limit corresponding to the steering angle of the machine body 3 detected by the state detection device 27. The on-board control device 21 inputs command signals to each part of the remote-controlled work machine 1, and controls the machine body 3 (remote-controlled work machine 1) to travel so as not to exceed the speed limit.

[0075] Fig. 8 is a flowchart showing the operation of the work machine 1 and the remote device 30. Each step in the flowchart shown on the left side of Fig. 8 is executed by the on-board control device 21 in remote mode based on a software program stored in the storage device 22. Each step in the flowchart shown on the right side of Fig. 8 is executed by the control device 31 of the remote device 30 based on a software program stored in the storage device 32.

[0076] When the remote operator inputs an operation instruction using the remote control device 35, the control device 31 transmits a remote control signal corresponding to the operation instruction to the remote-operated work machine 1 via the first communication device 33 (S1).

[0077] When the on-board control device 21 in the remote mode receives a remote control signal from the remote device 30 via the second communication device 23 (S11), it acquires (S12) the current vehicle speed limit of the work machine 1. In detail, the on-board control device 21 refers to the vehicle speed limit map M and acquires the vehicle speed limit corresponding to the current steering angle of the machine body 3 detected by the state detection device 27.

[0078] When the on-board control device 21 acquires the vehicle speed limit, it performs driving control and steering control of the remotely operated work machine 1 based on the vehicle speed limit (S13). Specifically, the on-board control device 21 controls the operation of each part of the remotely operated work machine 1 based on the remote control signal, the vehicle speed limit, the detection information from the position detection device 24, the sensing information from the second detection device 26, and the detection information from the state detection device 27. For example, if the traveling speed of the remotely operated work machine 1 acquired by the state detection device 27 exceeds the vehicle speed limit, or if the traveling speed is the vehicle speed limit and is increasing, the on-board control device 21 inputs an instruction signal to each part of the remotely operated work machine 1 to brake or decelerate the traveling device 7.

[0079] The on-board control device 21 again acquires the detection information from the position detection device 24, the sensing information from the second detection device 26, and the detection information from the status detection device 27, and transmits them to the remote device 30 via the second communication device 23 (S14).

[0080] When the control device 31 of the remote device 30 receives the detection information and sensing information via the first communication device 33 (S2), the control device 31 temporarily stores the information in the internal memory 31a and then reads it in. Then, the control device 31 (display control unit 31b) displays the display screen W1 on the display device 34 based on the read detection information and sensing information (S3), and the process returns to step S1.

[0081] Through the above processing, the on-board control device 21 controls the remote-controlled work machine 1 based on the remote control signal received from the remote device 30, the detection information acquired by each part of the remote-controlled work machine 1, the sensing information, and the vehicle speed limit. As a result, the traveling device 7 can cause the machine body 3 to travel at or below the vehicle speed limit according to the steering angle.

[0082] The traveling device 7 may cause the machine body 3 to travel at or below a speed limit corresponding to the work device 2 connected to the coupling device 8. For example, the traveling device 7 causes the machine body 3 to travel at or below a lower speed limit when the work device 2 is connected to the coupling device 8 compared to when the work device 2 is not connected to the coupling device 8.

[0083] 7A is a diagram showing an example of a vehicle speed limit map M' based on the attachment of a work device 2. The on-board control device 21 corrects the vehicle speed limit map M in accordance with the work device 2 connected to the coupling device 8, and obtains the vehicle speed limit from the corrected vehicle speed limit map M'. For example, the on-board control device 21 corrects the vehicle speed limit map M using a first correction value based on the work device 2 connected to the coupling device 8, so that the vehicle speed limit is lower when the work device 2 is connected to the coupling device 8 compared to when the work device 2 is not connected to the coupling device 8.

[0084] Furthermore, in addition to whether or not the work implement 2 is connected, the on-board control device 21 may also correct the limited vehicle speed map M using a first correction value based on the connected work implement 2 when the work implement 2 is connected to the coupling device 8.

[0085] For example, the on-board control device 21 corrects the vehicle speed limit map M so that the vehicle speed limit is lower when the center of gravity of the working device 2 connected to the coupling device 8 is high compared to when the center of gravity of the working device 2 connected to the coupling device 8 is low. The on-board control device 21 also corrects the vehicle speed limit map M so that the vehicle speed limit is lower when the weight of the working device 2 connected to the coupling device 8 is heavy compared to when the weight of the working device 2 connected to the coupling device 8 is light. In the present embodiment, the on-board control device 21 multiplies the vehicle speed limit corresponding to the steering angle identified from the vehicle speed limit map M by the first correction value to identify the corrected vehicle speed limit map M'.

[0086] A first correction value is defined for each work device 2 coupled to the coupling device 8, and these first correction values ​​are stored in the storage device 22 as a table associated with the identification information of the work device 2. In this embodiment, the on-board control device 21 sets the first correction value to "1" when no work device 2 is coupled to the coupling device 8. In more detail, the on-board control device 21 corrects the vehicle speed limit map M in accordance with changes in the state of the work device 2, and stores the corrected vehicle speed limit map M' in the memory 21b. For example, the on-board control device 21 corrects the vehicle speed limit map M when the third detection device 28 detects the attachment or detachment of a work device 2.

[0087] The on-vehicle control device 21 obtains whether or not a work device 2 is coupled to the coupling device 8, and identification information for the coupled work device 2. The on-vehicle control device 21 obtains whether or not a work device 2 is coupled using the third detection device 28, and if a work device 2 is coupled, obtains identification information for that work device 2 from the third detection device 28. The on-vehicle control device 21 obtains a first correction value from the storage device 22 based on the information obtained from the third detection device 28, and corrects the vehicle speed limit map M based on the first correction value.

[0088] The example shown in FIG. 7A shows a vehicle speed limit map M'1 when the coupling device 8 does not couple the working implement 2, and vehicle speed limit maps M'2 and M'3 when the coupling device 8 couples the working implement 2. In particular, the vehicle speed limit map M'3 is a vehicle speed limit map M when the center of gravity of the working implement 2 coupled to the coupling device 8 is higher than that of the vehicle speed limit map M'2. As shown in FIG. 7A, the vehicle speed limit maps M'1 to M'3 have different vehicle speed limits. The vehicle speed limit maps M'1 to M'3 are located closer to the zero side in this order: vehicle speed limit maps M'1, M'2, M'3. For this reason, the vehicle speed limit map M'2 has a lower vehicle speed limit than the vehicle speed limit map M'1. Furthermore, the vehicle speed limit map M'3 has a lower vehicle speed limit than the vehicle speed limit map M'2.

[0089] In the above example, the on-board control device 21 obtained information about the work device 2 connected to the coupling device 8 (the presence or absence of the work device 2 and its identification information) based on the detection results of the third detection device 28, but the above information may also be identified based on manual input by the remote operator (for example, manual input to the remote device 30) and the limit vehicle speed map M may be corrected.

[0090] Furthermore, in the above example, a case has been described in which the on-board control device 21 corrects the limit vehicle speed map M for each work device 2 connected to the coupling device 8, but it is sufficient that at least the traveling device 7 causes the machine body 3 to travel at or below the limit vehicle speed corresponding to the work device 2, and a configuration may be adopted in which the limit vehicle speed map M' for when no work device 2 is connected and the limit vehicle speed map M' corresponding to each work device 2 are stored in advance in the memory device 22, and the on-board control device 21 acquires the limit vehicle speed map M' that satisfies the conditions of the coupling device 8 (whether or not a work device 2 is connected, and the work device 2 connected to the coupling device 8).

[0091] Furthermore, the conditions corresponding to the work implement 2 connected to the coupling device 8 are not limited to the examples described above. For example, the speed limit map M does not have to be set (corrected or defined) for each work implement 2, but may be set in accordance with the type of work implement 2 (cultivator, sprayer, etc.), the operating state of the work implement 2 (driven and stopped), the height of the work implement 2 above ground, etc.

[0092] Furthermore, the traveling device 7 may travel the machine 3 at a speed limit or less that varies depending on the attitude of the remote-controlled work machine 1, separately from the work device 2. In particular, the traveling device 7 may travel the machine 3 at a speed limit or less that decreases as the attitude of the remote-controlled work machine 1 detected by the first detection device 25 tilts with respect to the horizontal. In other words, the traveling device 7 may travel the machine 3 at a speed limit or less that increases as the attitude of the remote-controlled work machine 1 detected by the first detection device 25 approaches the horizontal.

[0093] 7B is a diagram showing an example of a vehicle speed limit map M' based on the attitude of the remote-controlled work machine 1. The on-board control device 21 corrects the vehicle speed limit map M in accordance with the attitude of the remote-controlled work machine 1 detected by the first detection device 25, and obtains the vehicle speed limit from the corrected vehicle speed limit map M'. For example, the on-board control device 21 corrects the vehicle speed limit map M using a second correction value based on the attitude of the remote-controlled work machine 1 so that the vehicle speed limit is lower when the attitude of the remote-controlled work machine 1 is tilted from the horizontal state than when the attitude of the remote-controlled work machine 1 is not tilted from the horizontal state. In this embodiment, the on-board control device 21 specifies the corrected vehicle speed limit map M' by multiplying the vehicle speed limit corresponding to the steering angle specified from the vehicle speed limit map M by the second correction value.

[0094] The second correction value is calculated, for example, by a function that uses the pitch angle θp and / or the roll angle θr as input arguments. The second correction value does not have to be calculated by the function. Instead, the storage device 22 may store a table that associates the second correction value with the level of the pitch angle θp and / or the roll angle θr (the angle divided into a predetermined range) and the on-board control device 21 may refer to the table to determine the second correction value. In this embodiment, the on-board control device 21 sets the second correction value to "1" when the attitude of the remote-controlled work machine 1 is horizontal. Specifically, the on-board control device 21 corrects the speed limit map M in response to changes in the attitude of the remote-controlled work machine 1 and stores the corrected speed limit map M' in the memory 21b. For example, the on-board control device 21 corrects the speed limit map M when the first detection device 25 detects a change in the attitude of the remote-controlled work machine 1.

[0095] The example shown in Figure 7B shows a vehicle speed limit map M'4 when the attitude of the remote-controlled work machine 1 is horizontal, i.e., when the pitch angle θp and roll angle θr are zero; a vehicle speed limit map M'5 when the absolute value of the pitch angle θp or roll angle θr is a predetermined value θ1; and a vehicle speed limit map M'6 when the absolute value of the pitch angle θp or roll angle θr is a predetermined value θ2 (θ2 > θ1). As shown in Figure 7B, the vehicle speed limit maps M'4 to M'6 have different vehicle speed limits. The vehicle speed limit maps M'4 to M'6 are located closer to the zero side, in the order of M'4, M'5, and M'6. Therefore, the vehicle speed limit map M'5 defines a lower vehicle speed limit than the vehicle speed limit map M'4. Furthermore, the vehicle speed limit map M'6 defines a lower vehicle speed limit than the vehicle speed limit map M'5.

[0096] In the above example, we have explained a case where the on-board control device 21 corrects the limit vehicle speed map M in accordance with the attitude of the remote work machine 1, but it is sufficient if at least the traveling device 7 causes the machine body 3 to travel at or below the limit vehicle speed in accordance with the attitude of the remote work machine 1, and a configuration may be adopted in which the limit vehicle speed maps M, M' corresponding to the attitude of the remote work machine 1 are stored in advance in the memory device 22, and the on-board control device 21 acquires the limit vehicle speed maps M, M' corresponding to the attitude.

[0097] Furthermore, the traveling device 7 may cause the machine 3 to travel at or below a speed limit that varies depending on the gradient of the surrounding area of ​​the remote-controlled work machine 1, regardless of the attitude of the remote-controlled work machine 1. In particular, the traveling device 7 may cause the machine 3 to travel at or below a speed limit that decreases as the gradient of the surrounding area detected by the second detection device 26 increases. In other words, the traveling device 7 may cause the machine 3 to travel at or below a speed limit that increases as the gradient of the surrounding area detected by the second detection device 26 decreases.

[0098] 7C is a diagram showing an example of a vehicle speed limit map M' based on the gradient around the remote-controlled work machine 1. The on-board control device 21 corrects the vehicle speed limit map M according to the gradient (gradient value N) around the remote-controlled work machine 1 detected by sensing using the second detection device 26 ( FIG. 3C ), and obtains the vehicle speed limit from the corrected vehicle speed limit map M'. For example, the on-board control device 21 corrects the vehicle speed limit map M using a third correction value based on the gradient value N so that the vehicle speed limit is lower when the gradient value N is large than when the gradient value N is small. In this embodiment, the on-board control device 21 multiplies the vehicle speed limit corresponding to the steering angle determined from the vehicle speed limit map M by the third correction value to determine the corrected vehicle speed limit map M'.

[0099] The third correction value is calculated, for example, by a function that uses the gradient value N as an input argument. The third correction value does not have to be calculated by the function. Instead, the storage device 22 may store a table that associates the levels of the gradient value N (stages obtained by dividing the gradient value N into predetermined ranges) with the third correction value, and the on-board control device 21 may refer to the table to determine the third correction value. In this embodiment, the on-board control device 21 sets the correction value to "1" when the remote-controlled work machine 1 is in a horizontal position. Specifically, the on-board control device 21 corrects the vehicle speed limit map M in response to changes in the gradient value N and stores the corrected vehicle speed limit map M' in the memory 21b. For example, the on-board control device 21 corrects the vehicle speed limit map M when the first detection device 25 detects a change in the gradient value N.

[0100] The example shown in FIG. 7C shows a vehicle speed limit map M'7 when the gradient around the remote-controlled work machine 1 is relatively small, i.e., when the gradient value N detected by the second detection device 26 is less than a predetermined value N1; a vehicle speed limit map M'8 when the gradient value N detected by the second detection device 26 is the predetermined value N1; and a vehicle speed limit map M'9 when the gradient value N detected by the second detection device 26 is the predetermined value N2 (N2 > N1). As shown in FIG. 7C, the vehicle speed limit maps M'7 to M'9 have different vehicle speed limits. The vehicle speed limit maps M'7 to M'9 are located closer to the zero side, in the order of M'7, M'8, and M'9. Therefore, the vehicle speed limit map M'8 defines a lower vehicle speed limit than the vehicle speed limit map M'7. Furthermore, the vehicle speed limit map M'9 defines a lower vehicle speed limit than the vehicle speed limit map M'8.

[0101] In the above example, the on-board control device 21 corrects the limit vehicle speed map M in accordance with the gradient (gradient value N) around the remote work machine 1, but it is sufficient that at least the traveling device 7 causes the vehicle body 3 to travel at or below the limit vehicle speed according to the gradient of the surrounding area, and a configuration may be adopted in which the memory device 22 pre-stores limit vehicle speed maps M, M' corresponding to the gradient value N, and the on-board control device 21 acquires the limit vehicle speed maps M, M' corresponding to the attitude.

[0102] Furthermore, in the above-described example, the second detection device 26 sensed the surroundings of the remote work machine 1 and detected the gradient around the remote work machine 1, but the on-board control device 21 may also identify the gradient around the remote work machine 1 based on the position of the remote work machine 1 detected by the position detection device 24 and map information (gradient map) indicating the gradient that has been stored in advance in the memory device 22 of the remote work machine 1.

[0103] The gradient map is, for example, driving history data that associates position information detected by the position detection device 24 with gradient values ​​N detected by the second detection device (sensing device) 26 during past remote driving performed by the remote-controlled work machine 1. The driving history data may be data acquired during manual driving by a driver on board the remote-controlled work machine 1 or during automatic driving, which will be described later.

[0104] The on-board control device 21 stores (accumulates) the position information and the gradient value N corresponding to the position information as travel history data in the storage device 22 of the remote-controlled work machine 1. Note that the travel history data may be acquired by a work machine other than the remote-controlled work machine 1. The travel history data of the other work machine is stored in the storage device 22 via the second communication device 23.

[0105] The gradient map may be geographic information generated by a system separate from the remote-operated work machine 1 and the remote control system 100. The geographic information is stored in the storage device 22 via the second communication device 23. In the example described above, the on-board control device 21 identifies the gradient around the remote-operated work machine 1 based on the position of the remote-operated work machine 1 performing remote traveling and the gradient map, and the traveling device 7 causes the machine 3 to travel at or below a different speed limit depending on the gradient. However, the traveling device 7 may also cause the machine 3 to travel at or below a different speed limit depending on the position of the remote-operated work machine 1 and map information indicating information other than the gradient.

[0106] For example, the map information may include a field and roads (e.g., farm roads) surrounding the field, and the on-board control device 21 may identify whether the remote-controlled work machine 1 is located in a field or on a road based on the position of the remote-controlled work machine 1 performing remote traveling and the map information, and the traveling device 7 may cause the machine body 3 to travel at or below a different speed limit depending on the position. In such a case, the on-board control device 21 corrects the speed limit map M so that the speed limit is lower when the remote-controlled work machine 1 is located on a road than when it is located in a field.

[0107] Furthermore, in the above explanation, the cases where the traveling device 7 causes the machine body 3 to travel at or below a speed limit corresponding to the working device 2 connected to the coupling device 8, the cases where the traveling device 7 causes the machine body 3 to travel at or below a different speed limit depending on the attitude of the remote-controlled work machine 1, and the cases where the traveling device 7 causes the machine body 3 to travel at or below a different speed limit depending on the gradient around the remote-controlled work machine 1 have been individually described, but these may also be combined as appropriate. For example, the on-board control device 21 may specify a corrected speed limit map M' using at least one of the first to third correction values, and obtain the speed limit from the corrected speed limit map M'.

[0108] Furthermore, in the above example, the traveling device 7 causes the vehicle 3 to travel at or below a speed limit corresponding to the steering angle during remote control. However, the on-board control device 21 may also limit the traveling speed during traveling other than remote control. For example, the traveling device 7 may cause the vehicle 3 to travel at or below a predetermined speed limit even during manual traveling. In this embodiment, similar to remote traveling, the traveling device 7 causes the vehicle 3 to travel at or below a speed limit corresponding to the steering angle during manual traveling. Specifically, in manual mode, the on-board control device 21 refers to a speed limit map MH pre-stored in the storage device 22 and obtains a speed limit corresponding to the current steering angle of the vehicle 3 detected by the state detection device 27. Furthermore, upon obtaining the speed limit, the on-board control device 21 performs traveling control and steering control of the remote-controlled work machine 1 based on the speed limit.

[0109] Furthermore, when the remote-controlled work machine 1 is traveling automatically (in automatic mode) along a predetermined travel route, the vehicle 3 may be driven at a speed equal to or lower than a predetermined speed limit. In this case, similar to remote control, the traveling device 7 drives the vehicle 3 automatically at a speed equal to or lower than a speed limit corresponding to the steering angle. In automatic mode, the on-board control device 21 controls the actuators and the operation of each part of the remote-controlled work machine 1 so that the position deviation and / or azimuth deviation between the travel route and the remote-controlled work machine 1 approaches zero based on a predetermined travel route predefined in the storage device 22, the position of the remote-controlled work machine 1 detected by the position detection device 24, and the like. In this case, the on-board control device 21 in automatic mode references a speed limit map MO prestored in the storage device 22 and acquires a speed limit corresponding to the current steering angle of the vehicle 3 detected by the state detection device 27. Furthermore, upon acquiring the speed limit, the on-board control device 21 controls the travel and steering of the remote-controlled work machine 1 based on the speed limit.

[0110] FIG. 7D is a diagram showing an example of a vehicle speed limit map MH of the remotely operated work machine 1 during manual driving and an example of a vehicle speed limit map MO of the remotely operated work machine 1 during automatic driving. The example shown in FIG. 7D shows a vehicle speed limit map M when remote driving is performed, a vehicle speed limit map MH when the remotely operated work machine 1 is manually driven, and a vehicle speed limit map MH when automatic driving is performed. As shown in FIG. 7D , the vehicle speed limit maps M, MH, and MO have different vehicle speed limits. As is clear from FIG. 7D , the vehicle speed limit map M has a lower vehicle speed limit than the vehicle speed limit maps MH and MO. Furthermore, in the example shown in FIG. 7D , the vehicle speed limit map MO has a lower vehicle speed limit than the vehicle speed limit map MH.

[0111] In the example shown in Figure 7D, the limit vehicle speed maps MH and MO are curved like the limit vehicle speed map M, and the limit vehicle speed fluctuates relatively more when the steering angle is large than when the steering angle is small. However, it is sufficient that at least the limit vehicle speed maps MH and MO have a higher limit vehicle speed corresponding to the same steering angle than the limit vehicle speed map M and the corrected limit vehicle speed map M', and the limit vehicle speed maps MH and MO are approximately straight, and the limit vehicle speed and the steering angle may be proportional to each other or may be constant regardless of the steering angle.

[0112] Furthermore, in the above example, the memory device 22 is described as storing all of the limit vehicle speed maps M, MH, and MO, but the memory device 22 may store any one of the limit vehicle speed maps M, MH, and MO, and the on-board control device 21 may identify another limit vehicle speed map based on that one limit vehicle speed map and a predetermined calculation formula.

[0113] <Modification> In the remote control system 100 of the above embodiment, the on-board control device 21 performs driving control based on the vehicle speed limit. However, in the remote control system 100 of the modification, as shown in FIG. 9 , the remote device 30 generates a remote control signal in accordance with the vehicle speed limit and transmits it to the remote work machine 1, which is different from the remote control system 100 of the above embodiment.

[0114] In the embodiment described above, the vehicle speed limit map M is stored in the storage device 22 of the remote-controlled work machine 1, and the on-board control device 21 obtains the vehicle speed limit based on the vehicle speed limit maps M and M'. However, in a modified example, the vehicle speed limit map M is stored in the storage device 32 of the remote device 30, and the control device 31 obtains the vehicle speed limit based on the vehicle speed limit maps M and M'. The on-board control device 21 periodically transmits current detection information and sensing information of the remote-controlled work machine 1 to the remote device 30 via the second communication device 23. When the remote device 30 receives the detection information and sensing information via the first communication device 33, it temporarily stores them in its internal memory 31a.

[0115] FIG. 9 is a flowchart showing the operation of the remote-controlled work machine 1 and the remote device 30 in a modified example. When a remote operator inputs an operation command for the remote-controlled work machine 1 by operating the remote control device 35, the control device 31 references the speed limit map M stored in the storage device 32 and obtains the speed limit corresponding to the current steering angle of the remote-controlled work machine 1 stored in the internal memory 31a (S4). The control device 31 generates a remote control signal based on the operation command and the speed limit (S5). For example, when the remote operator operates the accelerator pedal 35b, the control device 31 converts the operation command into a remote control signal that does not exceed the speed limit. The remote control signal is transmitted to the remote-controlled work machine 1 by the first communication device 33 (S1).

[0116] A preferred embodiment of the present invention provides a remote control system 100 as described in the following sections.

[0117] (Item A1) A remote control system 100 comprising a machine body 3, a working device 2 supported on the machine body 3, a remote work machine 1 having a traveling device 7 that supports the machine body 3 so that it can travel, and a remote control device 35 that receives operations and remotely controls the remote work machine 1, wherein the traveling device 7 causes the machine body 3 to travel at or below a limited vehicle speed that corresponds to a steering angle during the remote control.

[0118] According to the remote control system 100 according to item A1, the remote-controlled work machine 1 can be driven stably even when remotely controlled by a remote operator.

[0119] (Item A2) The remote control system 100 according to Item A1, wherein the traveling device 7 causes the vehicle 3 to travel at or below the speed limit, which decreases as the steering angle increases, during the remote control.

[0120] According to the remote control system 100 according to item A2, the remote operator can drive the remote-controlled work machine 1 stably even when the steering angle is large.

[0121] (Item A3) The remotely controlled system 100 described in Item A1, in which the remote work machine 1 has a coupling device 8 that detachably couples the work device 2 to the machine body 3, and the traveling device 7 causes the machine body 3 to travel at or below the limited vehicle speed corresponding to the work device 2 coupled to the coupling device 8.

[0122] According to the remote control system 100 according to item A3, the remote operator can appropriately drive the remote-controlled work machine 1 depending on the work device 2 to which it is connected.

[0123] (Item A4) The remote control system 100 described in Item A3, in which the traveling device 7 causes the machine body 3 to travel at or below the limited vehicle speed, which is lower when the working device 2 is connected to the coupling device 8 than when the working device 2 is not connected to the coupling device 8.

[0124] According to the remote control system 100 according to item A4, the remote operator can stably drive the remote-controlled work machine 1 to which the work device 2 is connected.

[0125] (Item A5) A remote control system 100 as described in Item A1, which is provided with a first detection device 25 that detects the attitude of the remote work machine 1, and the traveling device 7 causes the vehicle body 3 to travel at or below the limited vehicle speed, which becomes lower as the attitude of the remote work machine 1 detected by the first detection device 25 becomes inclined relative to the horizontal state.

[0126] According to the remote control system 100 according to item A5, the remote operator can make the remote-controlled work machine 1 travel stably according to the attitude of the remote-controlled work machine 1 while traveling.

[0127] (Item A6) A remote control system 100 as described in Item A1, which is provided with a second detection device 26 that detects the gradient of the surroundings of the remote work machine 1, and the traveling device 7 causes the machine body 3 to travel at or below the limited vehicle speed, which decreases as the gradient of the surroundings detected by the second detection device 26 increases.

[0128] According to the remote control system 100 according to item A6, the remote operator can stably drive the remote-controlled work machine 1 according to the gradient of the surroundings of the remote-controlled work machine 1.

[0129] (Item A7) The remote control system 100 according to Item A6, wherein the second detection device 26 is a sensing device that senses the surroundings of the remote-controlled work machine 1 and detects the gradient of the surroundings of the remote-controlled work machine 1.

[0130] According to the remote control system 100 relating to item A7, the second detection device 26 detects the gradient around the remote work machine 1 in a timely manner, and the remote operator can drive the remote work machine 1 stably according to the current conditions around the remote work machine 1.

[0131] (Item A8) The second detection device 26 of the remote control system 100 described in Item A6 detects the gradient around the remote work machine 1 based on a position detection device 24 that detects the position of the remote work machine 1, the position of the remote work machine 1 detected by the position detection device 24, and map information indicating the gradient stored in the memory device 22.

[0132] According to the remote control system 100 relating to item A8, the vehicle speed limit is defined according to the slope of the area around the remote work machine 1 obtained from the map information, so that the remote work machine 1 can be driven stably with relatively simple processing.

[0133] (Item A9) The remotely controlled system 100 described in Item A1 is capable of automatic driving, i.e., autonomous driving, and / or manual driving operated by a driver on board the remotely controlled work machine 1, in addition to the remote control by the remote control device 35, and the driving device 7 drives the vehicle 3 at or below the limited vehicle speed, which is lower when the remotely controlled work machine 1 is driving automatically or manually, compared to when the remotely controlled work machine 1 is driving automatically or manually.

[0134] According to the remote control system 100 relating to item A9, even in remote control where it is not easy to accurately grasp the state of the remote work machine 1, the remote work machine 1 can travel stably, just like other automatic and manual travel.

[0135] 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.

[0136] REFERENCE SIGNS LIST 1: Remote-controlled work machine 2: Work device 3: Machine body 7: Traveling device 8: Coupling device 22: Storage device 24: Position detection device 25: First detection device 26: Second detection device 35: Remote control device 100: Remote control system

Claims

1. A remote working machine having a machine body, a working device supported by the machine body, and a traveling device that supports the machine body so as to be travelable, and a remote control device that receives an operation and remotely controls the remote working machine, wherein the traveling device is a remote control system that causes the machine body to travel at a limited vehicle speed or less according to a steering angle in the remote control.

2. The remote control system according to claim 1, wherein the traveling device causes the machine body to travel at a limited vehicle speed or less that decreases as the steering angle increases in the remote control.

3. The remote working machine has a connecting device that detachably connects the working device to the machine body, and the traveling device is the remote control system according to claim 1 that causes the machine body to travel at a limited vehicle speed or less according to the working device connected to the connecting device.

4. The remote control system according to claim 3, wherein the traveling device causes the machine body to travel at a limited vehicle speed or less that is lower when the working device is connected to the connecting device than when the working device is not connected to the connecting device.

5. The remote control system according to claim 1, further comprising a first detection device that detects the attitude of the remote working machine, and the traveling device causes the machine body to travel at a limited vehicle speed or less that decreases as the attitude of the remote working machine detected by the first detection device inclines with respect to the horizontal state.

6. The remote control system according to claim 1, further comprising a second detection device that detects the gradient around the remote working machine, and the traveling device causes the machine body to travel at a limited vehicle speed or less that decreases as the gradient around the remote working machine detected by the second detection device increases.

7. The remote control system according to claim 6, wherein the second detection device is a sensing device that senses the surroundings of the remote working machine and detects the gradient around the remote working machine.

8. The remote control system according to claim 6, wherein the second detection device detects the gradient around the remote working machine based on a position detection device that detects the position of the remote working machine, the position of the remote working machine detected by the position detection device, and map information indicating the gradient stored in a storage device.

9. In addition to the remote control by the remote control device, the remote working machine is capable of autonomous driving in which it travels autonomously and / or manual driving in which a driver on board the remote working machine operates it. The traveling device causes the machine body to travel at a speed equal to or lower than the restricted vehicle speed, which is lower during the remote control than when the remote working machine performs the autonomous driving or the manual driving. The remote control system according to claim 1.

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