Vehicle control system

Abstract

A vehicle control system capable of eliminating deterioration in radio quality and improving the safety and productivity of various vehicles comprises: radio terminals mounted on a first vehicle and a second vehicle and capable of communicating with a base station; and a vehicle control supervision server device disposed in a supervision station that communicates with the radio terminals via the base station, wherein the vehicle control supervision server device determines whether the vehicles are in proximity to each other on the basis of position information of the respective vehicles transmitted from the radio terminals via the base station by using a first communication line, and transmits and receives the position information of the respective vehicles to and from the respective vehicles via the base station by using a second communication line when it is determined that the vehicles are in proximity to each other, the first communication line and the second communication line are a first radio bearer and a second radio bearer that are different from each other while having the same radio channel with respect to the radio terminals, and the first radio bearer and the second radio bearer have different communication priorities.

Description

Vehicle control system

[0001] The present invention relates to a vehicle control system for various vehicles running at a mine site.

[0002] At a mine site or the like, there is an increasing demand to make various vehicles run autonomously from the viewpoints of suppressing labor costs and improving safety. As a response to this demand, for example, a vehicle control system that makes a dump truck running at a mine site run autonomously without a driver is known.

[0003] For example, in Patent Document 1, a plurality of vehicles transmit position data of their own vehicle positions to a monitoring station using wireless communication by a first communication method capable of wireless communication with the monitoring station at a distance between each of the plurality of vehicles and the monitoring station. The monitoring station monitors the positional relationship between the vehicles based on the position data. When the presence of nearby vehicles is confirmed, information to this effect is transmitted to the nearby vehicles using wireless communication by the first communication method. The nearby vehicles to which this information is transmitted transmit and receive position data between the vehicles using wireless communication between the vehicles by a second communication method capable of wireless communication between the vehicles, and a technique for performing control to prevent interference between the vehicles is disclosed.

[0004] Japanese Patent Laid-Open No. 10-222227

[0005] When wireless communication is performed between vehicles at a mine site (hereinafter referred to as vehicle-to-vehicle communication), wireless quality degradation peculiar to vehicle-to-vehicle communication can occur, such as oncoming vehicles being out of sight due to curves and gradients with poor visibility, or large vehicles that cause shielding between vehicles entering.

[0006] The technique disclosed in the above Patent Document 1 may cause problems such as a decrease in communication speed or communication interruption due to such wireless quality degradation peculiar to vehicle-to-vehicle communication, leading to a problem of productivity degradation due to deceleration or stop of the driverless dump truck running autonomously.

[0007] Further, the technique disclosed in the above Patent Document 1 requires each vehicle to be equipped with two types of wireless terminals having different communication methods, namely, the first communication method and the second communication method. Equipping each vehicle with two types of wireless terminals having different communication methods is not desirable because the installation location, cost, and probability of equipment failure increase.

[0008] Therefore, the present invention has been made in view of the above problems, and provides a vehicle control system that does not suffer from the degradation of wireless quality that is characteristic of inter-vehicle communication, and does not require each vehicle to be equipped with multiple transceivers with different communication methods, thereby enabling improvements in vehicle safety and productivity.

[0009] The vehicle control system according to the present invention comprises a wireless terminal mounted on each of a first vehicle and a second vehicle and capable of communicating with a base station, and a vehicle control server device located in a control station that communicates with the wireless terminals via the base station, wherein the vehicle control server device determines whether the first vehicle and the second vehicle are in close proximity to each other based on the location information of each of the first vehicle and the second vehicle transmitted from the wireless terminals mounted on the first vehicle and the second vehicle via the base station using a first communication line, and if it is determined that they are in close proximity, it transmits and receives the location information of each of the first vehicle and the second vehicle via the base station using a second communication line, wherein the first communication line and the second communication line are different first and second wireless bearers, although they are on the same wireless channel to the wireless terminals, and the first and second wireless bearers have different communication priorities.

[0010] According to the vehicle control system of the present invention, there is no degradation in wireless quality specific to inter-vehicle communication, and since each vehicle does not need to be equipped with multiple wireless terminals with different communication methods, the probability of equipment failure does not increase, thereby enabling improvements in vehicle safety and productivity.

[0011] This is a schematic diagram showing an example of the overall configuration of the vehicle control system 1000 according to the first embodiment. This is a block diagram illustrating an example of the configuration of the in-vehicle wireless terminal 2. This is a block diagram illustrating an example of the configuration of the in-vehicle wireless terminal 1. This is a schematic diagram illustrating the operation of the vehicle control system 1000 according to the embodiment. This is a diagram showing the relationship between the distance between vehicles X and the proximity detection distance Y. This is a diagram showing an example of the proximity detection distance Y between two unmanned dump trucks 10. This is a diagram showing an example of the proximity detection distance Y between an unmanned dump truck 10 and a manned vehicle 20. This is a characteristics table showing the priority, transmission interval, and TYPE of each wireless bearer. This is a diagram showing the packet reception timing in the network load monitoring function according to the embodiment of the present invention. This is a diagram showing the distribution of the occurrence probability of packet reception intervals in the network load monitoring function according to the embodiment of the present invention. This is a flowchart that explains in detail the operation of the in-vehicle wireless terminal 2 according to the embodiment regarding the transmission of location information and emergency stop signals. This is a flowchart that explains in detail the operation of the in-vehicle wireless terminal 2 according to the embodiment regarding the transmission of location information and emergency stop signals in the proximity state. This is a flowchart that explains in detail the operation of the in-vehicle wireless terminal 1 according to the embodiment regarding the reception of location information and emergency stop signals. This flowchart provides a detailed explanation of the proximity detection operation using location information in the vehicle control server 31 of the embodiment. This flowchart provides a detailed explanation of the proximity detection operation using location information in the vehicle control server 31 of the second embodiment. This flowchart provides a detailed explanation of the proximity detection operation using location information in the vehicle control server 31 of the third embodiment.

[0012] This embodiment will be described below with reference to the attached drawings. In the attached drawings, functionally identical elements are indicated by the same number. The attached drawings show embodiments and implementation examples in accordance with the principles of this disclosure, but these are for the purpose of understanding this disclosure and are not to be used in any way to restrict the interpretation of this disclosure. The descriptions in this specification are merely typical examples and do not limit the claims or applications of this disclosure in any way.

[0013] While this embodiment is described in sufficient detail for those skilled in the art to implement the disclosure, it is important to understand that other implementations and forms are possible, and that the configuration and structure can be modified and various elements replaced without departing from the scope and spirit of the technical idea of ​​this disclosure. Therefore, the following description should not be interpreted as limiting it to this embodiment.

[0014] [First Embodiment] Hereinafter, a vehicle control system according to the first embodiment of the present invention will be described in detail with reference to the drawings. Figure 1 is a schematic diagram showing an example of the overall configuration of the vehicle control system 1000 according to the first embodiment of the present invention. The vehicle control system 1000 has a function to make an unmanned dump truck drive autonomously and a function to stop an unmanned dump truck that is driving autonomously in an emergency.

[0015] In Figure 1, the vehicle control system 1000 includes vehicle-mounted wireless terminals 1-1 to 1-4, vehicle-mounted wireless terminals 2-1 and 2-2, wireless base stations 4-1 and 4-2, a wireless relay station 5, autonomously driving unmanned dump trucks 10-1 to 10-4, manned vehicles 20-1 and 20-2, and a control station 30. The vehicle control system 1000 is configured to perform vehicle control related to the autonomous driving of the unmanned dump trucks 10-1 to 10-4, vehicle control related to emergency stopping of the unmanned dump trucks 10-1 to 10-4, and other controls.

[0016] The vehicle control system 1000 is installed, for example, in a mine. The unmanned dump trucks 10-1 to 10-4 are vehicles capable of autonomous driving without a driver, and are operated without a driver in principle, and are controlled based on the vehicle control system 1000. The unmanned dump trucks 10-1 to 10-4 are transport vehicles that load and transport cargo such as soil and ore. The unmanned dump trucks 10-1 to 10-4 autonomously drive along a pre-set transport route 100 within the mine site without a driver. For example, a shovel (not shown) is placed at the loading area 200 to load soil and ore onto the unmanned dump truck 10-2, and the unmanned dump truck 10-2 travels back and forth between the loading area 200 and the unloading area 300 along the transport route 100, transporting the cargo. A vehicle control server 31 is also installed at the control station 30.

[0017] Each of the vehicle-mounted wireless terminals 1-1 to 1-4 is installed on an unmanned dump truck 10-1 to 10-4. Each of the vehicle-mounted wireless terminals 2-1 and 2-2 is installed on a manned vehicle 20-1 and 20-2. The number of each device is not limited to those shown in the illustration or specific numbers. For example, each of the vehicle-mounted wireless terminals 1-1 to 1-4 and the unmanned dump trucks 10-1 to 10-4 may be only one unit, or there may be multiple units of either or both. Similarly, each of the vehicle-mounted wireless terminals 2-1 and 2-2 and the manned vehicles 20-1 and 20-2 may be only one unit, or there may be multiple units of either or both.

[0018] Furthermore, although not shown in Figure 1, a system and operation management system to support autonomous driving for the unmanned dump trucks 10-1 to 10-4 are installed at the work site within the mine.

[0019] The configurations of the vehicle-mounted wireless terminals 1-1 to 1-4 may all be the same or different. Hereafter, vehicle-mounted wireless terminals 1-1 to 1-4 may be collectively referred to as "vehicle-mounted wireless terminal 1" without distinction. Similarly, vehicle-mounted wireless terminals 2-1 and 2-2 and wireless base stations 4-1 and 4-2 may be collectively referred to as "vehicle-mounted wireless terminal 2" and "wireless base station 4," respectively, without distinction. Also, the configurations of the unmanned dump trucks 10-1 to 10-4 may all be the same, so when referring to them collectively, they may be referred to as "unmanned dump truck 10." Manned vehicles 20-1 and 20-2 may also be collectively referred to as "manned vehicle 20."

[0020] At the mining site, in addition to unmanned dump trucks 10 that transport loads such as soil and ore, manned vehicles 20 also operate. Manned vehicles 20 are configured to accommodate a driver or other passengers and are designed to be driven by a driver. Examples of manned vehicles 20 include the aforementioned shovels, bulldozers for leveling the surface of the transport route 100, water trucks, service cars for patrolling the mining site, and manned dump trucks that are designed to be driven by a driver.

[0021] The vehicle-mounted wireless terminal 2 is a vehicle-mounted device installed in a manned vehicle 20. The vehicle-mounted wireless terminal 2 has a function to transmit an emergency stop signal in an emergency. The driver or passenger of the manned vehicle 20 can use the vehicle-mounted wireless terminal 2 to instruct the unmanned dump truck 10 to make an emergency stop in an emergency. For example, an emergency stop instruction signal can be transmitted from the transport route 100, loading area 200, and unloading area 300 within the site.

[0022] In this embodiment, the scope and meaning of "emergency" are not limited, and workers or drivers of manned vehicles 20 can determine whether or not an emergency has occurred and issue an emergency stop instruction based on their own judgment. Generally, whether or not an "emergency" has occurred is determined based on whether or not it is necessary to stop the unmanned dump truck 10. For example, if there is a possibility of contact or interference between two unmanned dump trucks 10, or between an unmanned dump truck 10 and a manned vehicle 20, it can be determined that an emergency has occurred. Also, if there is a possibility of contact or interference between an unmanned dump truck 10 and a worker, it can be determined that an emergency has occurred.

[0023] The vehicle-mounted wireless terminal 1 is a vehicle-mounted device installed on the unmanned dump truck 10. The vehicle-mounted wireless terminal 1 has the function of receiving driving control signals (driving permission and speed commands, etc.) necessary for the autonomous driving of the unmanned dump truck 10, and emergency stop signals necessary for the emergency stop of the unmanned dump truck 10. In the event of an emergency, the unmanned dump truck 10 can be brought to an emergency stop by the emergency stop signal transmitted from the vehicle-mounted wireless terminal 2. In addition, the unmanned dump truck 10 can drive autonomously by the driving control signals transmitted from the vehicle control server 31 located in the control station 30. The emergency stop signal transmitted from the vehicle-mounted wireless terminal 2 and the driving control signals transmitted from the vehicle control server located in the control station 30 are transmitted via the wireless base station 4, the wireless relay station 5, and the core network device 6.

[0024] The location of the antenna for the vehicle-mounted wireless terminal 1 installed on the unmanned dump truck 10 is not limited to a specific location. For example, it is preferable that the antenna be installed in a location where there is a clear line of sight to the radio waves from the wireless base station 4, for example, on the upper front surface of the unmanned dump truck 10.

[0025] Multiple wireless base stations 4 each constitute a wireless area called a cell, and are capable of wireless communication with unmanned dump trucks 10 and manned vehicles 20 located within the cell. For example, since the unmanned dump trucks 10 and manned vehicles 20 move to an area including a transport route 100, a loading area 200, and a soil disposal area 300, the multiple wireless base stations 4 are arranged so that the unmanned dump trucks 10 and manned vehicles 20 can communicate wirelessly in these areas.

[0026] The wireless base station 4 is connected to the vehicle control server 31 via the core network device 6 in the control station 30, through the wireless relay line 510 and the wireless relay station 5. Driving control signals necessary for the autonomous driving of the unmanned dump truck 10, emergency stop signals necessary for the emergency stop of the unmanned dump truck 10, position information necessary for proximity detection between the unmanned dump truck 10 and the manned vehicle 20, and position information necessary for proximity detection between the unmanned dump trucks 10 themselves are transmitted and received between the vehicle control server 31 via the wireless base station 4, the wireless relay line 510, the wireless relay station 5, and the core network device 6. The vehicle control server 31 has the function of transmitting driving control signals to the unmanned dump truck 10, thereby enabling the unmanned dump truck 10 to drive autonomously. Furthermore, the vehicle control server 31 has the function of transmitting an emergency stop signal sent from the on-board wireless terminal 2 mounted on the manned vehicle 20 to the on-board wireless terminal 1 mounted on the target unmanned dump truck 10 via the core network device 6, wireless relay station 5, wireless relay line 510, and each wireless base station 4. In addition, the vehicle control server 31 has the function of performing proximity detection determination between the unmanned dump truck 10 and the manned vehicle 20, and proximity detection determination between the unmanned dump trucks 10 themselves, based on location information sent from the on-board wireless terminal 1 mounted on the unmanned dump truck 10 and the on-board wireless terminal 2 mounted on the manned vehicle 20.

[0027] The vehicle control system 1000 can be configured to stop all unmanned dump trucks 10 or only a specific unmanned dump truck 10 if an emergency stop signal is issued from any of the on-board wireless terminals 2 to all unmanned dump trucks 10 within the mining site.

[0028] Vehicle-mounted wireless terminals 1 and 2 are equipped with GPS (Global Positioning System) receiving functions. They have the function of transmitting their own location information acquired by the GPS receiving function to the vehicle control server 31 located at the control station 30 via the wireless base station 4, wireless relay station 5, and core network device 6. The vehicle control server 31 has the function of managing its own location information sent from vehicle-mounted wireless terminals 1 and 2, and has the function of calculating the distance between the unmanned dump truck 10 and the manned vehicle 20, and the distance between the unmanned dump trucks 10 themselves, based on the managed location information, and performs proximity detection between the unmanned dump trucks 10 themselves, or between the unmanned dump trucks 10 and the manned vehicle 20, based on a predetermined proximity detection distance Y. It should be noted that the method of acquiring its own location information may be other than GPS.

[0029] Next, an example of the configuration of the in-vehicle wireless terminal 2 will be described with reference to Figure 2. As an example, the in-vehicle wireless terminal 2 is configured to include a transmitting / receiving antenna 101, a wireless modem 102, a microcontroller device 103, an external interface (I / F) 104, a power supply device 105, a display device 106, an emergency stop button 107, a GPS receiver 108, and a GPS antenna 109.

[0030] The wireless modem 102 in the in-vehicle wireless terminal 2 is composed of high-frequency circuits and integrated circuits. The wireless modem 102 is connected to the transmitting and receiving antenna 101 and performs wireless communication with the wireless base station 4 according to a predetermined wireless communication method (for example, LTE (Long Term Evolution)). The wireless modem 102 is also connected to the microcontroller device 103 and transmits the received signals to the microcontroller device 103. Specifically, the wireless signal 110 transmitted from the wireless base station 4 and received by the transmitting and receiving antenna 101 is input to the wireless modem 102, and after undergoing predetermined filtering, amplification, frequency conversion, demodulation, and error correction decoding, it is output as received data 112 in the microcontroller device 103.

[0031] Furthermore, the wireless modem 102 processes the transmission data 111 output from the microcontroller device 103 with error correction coding, modulation, frequency conversion, amplification, and filtering to generate a wireless signal 110, which is then output to the transmitting / receiving antenna 101.

[0032] The microcontroller device 103 consists of a CPU 801 (arithmetic processing unit) and a storage device 802 (main memory and flash memory, etc.), and is connected to a wireless modem 102, an external interface 104, a power supply 105, a display device 106, an emergency stop button 107, and a GPS receiver 108. The functions described below are realized when the program stored in the storage device 802 is calculated and executed by the CPU 801. Note that the microcontroller device 103 may be composed of integrated circuits or the like in part or all of it.

[0033] The external I / F 104 consists of a voltage conversion unit, a protocol conversion unit, and connectors, and is responsible for interfacing with external devices. Specifically, it is configured to perform voltage and protocol conversions required by external devices. The external I / F 104 is connected to various devices, such as an on-board controller device, which is mounted on the manned vehicle 20.

[0034] The power supply unit 105 consists of a battery 810 and a voltage converter 811, etc. The power supply unit 105 has the function of converting the power supplied from the battery 810 to the required voltage using the voltage converter 811, and then supplying it to each part of the in-vehicle wireless terminal 2.

[0035] The display device 106 consists of LEDs and a liquid crystal display device, and is connected to the microcontroller device 103. The display device 106 has the function of notifying the operator or maintenance personnel of the normality of the power supply and the result of the wireless communication interruption detection.

[0036] The emergency stop button 107 is connected to the microcomputer device 103 and is an operation button used by the operator to instruct the unmanned dump truck 10 to make an emergency stop. The emergency stop button 107 can be a push-button structure that detects an instruction from the operator when it is pressed. The emergency stop button 107 may also have a mechanism that locks when pressed and remains pressed until released.

[0037] The GPS receiver 108 is connected to the GPS antenna 109 and the microcontroller device 103, and acquires location information indicating the current position of the manned vehicle 20 from the GPS reception signal received via the GPS antenna 109. The GPS receiver 108 periodically (for example, every second) outputs the location information indicating the current position of the manned vehicle 20 to the microcontroller device 103. Here, the location information may be the latitude and longitude indicating the current position of the manned vehicle 20. The vehicle-mounted wireless terminal 2 may be a single physical box, or it may consist of multiple boxes separated by function.

[0038] Next, an example of the configuration of the vehicle-mounted wireless terminal 1 will be described with reference to Figure 3. As an example, the vehicle-mounted wireless terminal 1 is configured to include a transmitting / receiving antenna 101, a wireless modem 102, a microcontroller device 103, an external interface 104, a power supply device 105, a display device 106, a GPS receiver 108, and a GPS antenna 109. In other words, the vehicle-mounted wireless terminal 1 may have the same configuration as the vehicle-mounted wireless terminal 2, except that it does not have an emergency stop button 107. The external interface 104 is connected to various devices such as a vehicle-mounted controller device and a BCU (Brake Control Unit) installed on the unmanned dump truck 10, and transmits and receives driving control signals (driving permission and speed commands, etc.) necessary for the autonomous driving of the unmanned dump truck 10, and emergency stop signals necessary for the emergency stop of the unmanned dump truck 10.

[0039] Furthermore, since the vehicle control server 31 is implemented in a general server device and computer and does not represent a feature of the present invention, a detailed explanation of the device configuration of the vehicle control server 31 will be omitted.

[0040] Figure 4 is a schematic diagram illustrating the wireless connection status of an unmanned dump truck 10-1 (first vehicle), an unmanned dump truck 10-2 (second vehicle), on-board wireless terminals 1-1 and 1-2, and a wireless base station 4-1 in a vehicle control system 1000 according to a first embodiment of the present invention. Here, the wireless connection of the unmanned dump truck 10 is explained, but a similar wireless connection can be made for a manned vehicle 20. In order to cover the entire vast mining site, the vehicle control system 1000 is configured with multiple wireless base stations, but here, one wireless base station 4-1 is shown as an example.

[0041] Referring to Figure 4, the basic operation of the vehicle control system 1000 according to the first embodiment of the present invention will be described in detail. The vehicle-mounted wireless terminals 1-1 and 1-2 installed on the unmanned dump trucks 10-1 and 10-2 are capable of communicating with the wireless base station 4 using multiple wireless bearers, for example, a first wireless bearer and a second wireless bearer. Here, a wireless bearer refers to a logical data transmission path in wireless communication. The first wireless bearer and the second wireless bearer do not refer to wireless lines (transmission paths) with different frequencies or wireless methods (communication methods), but rather to wireless lines (transmission paths) that have the same frequency and the same wireless method but are logically different. In addition, the same or different priorities can be set for each wireless bearer. For example, the priority of the second wireless bearer is set to be higher than the priority of the first wireless bearer. Furthermore, the resolution of the position information sent by the second wireless bearer is set to be higher than that of the position information sent by the first wireless bearer. For example, the position information sent by the first wireless bearer is 16 bits, and the position information sent by the second wireless bearer is 32 bits. Furthermore, the transmission intervals of the position information of the unmanned dump truck 10 that is periodically sent using the first wireless bearer and the position information of the unmanned dump truck 10 that is periodically sent using the second wireless bearer are different. For example, the transmission interval of the position information that is periodically sent using the second wireless bearer is shorter than that of the position information that is periodically sent using the first wireless bearer. By making the transmission interval of the position information that is periodically sent using the second wireless bearer 202 shorter than that of the position information that is periodically sent using the first wireless bearer 201, more precise vehicle control of the unmanned dump truck 10 becomes possible, resulting in increased productivity, such as a shorter deceleration period. Furthermore, by making the resolution of the position information that is periodically sent using the second wireless bearer 202 higher than that of the position information that is periodically sent using the first wireless bearer 201, even more precise vehicle control of the unmanned dump truck 10 becomes possible, resulting in even greater productivity.

[0042] For example, in the conveyance path 100 of FIG. 4, a case where the driverless dump truck 10-1 (first vehicle) moves rightward from the left end and the driverless dump truck 10-2 (second vehicle) moves leftward from the right end will be used to explain in detail the operation of the vehicle control system 1000 according to the first embodiment of the present invention.

[0043] At time t1 (when there is no approaching vehicle), the driverless dump truck 10-1 transmits its own position information acquired by the GPS receiving function of the in-vehicle wireless terminal 1-1 to the vehicle control server 31 disposed in the control station 30 via the first radio bearer 201-1, the radio base station 4, the radio relay station 5, and the core network device 6. Similarly, at time t1, the driverless dump truck 10-2 transmits its own position information acquired by the GPS receiving function of the in-vehicle wireless terminal 1-2 to the vehicle control server 31 disposed in the control station 30 via the first radio bearer 201-2, the radio base station 4, the radio relay station 5, and the core network device 6.

[0044] At time t2 (when there is an approaching vehicle), the driverless dump truck 10-1 transmits its own position information acquired by the GPS receiving function of the in-vehicle wireless terminal 1-1 to the vehicle control server 31 disposed in the control station 30 via the first radio bearer 201-1, the radio base station 4, the radio relay station 5, and the core network device 6. Similarly, at time t2, the driverless dump truck 10-2 transmits its own position information acquired by the GPS receiving function of the in-vehicle wireless terminal 1-2 to the vehicle control server 31 disposed in the control station 30 via the first radio bearer 201-2, the radio base station 4, the radio relay station 5, and the core network device 6.

[0045] The vehicle control server 31 disposed in the control station 30 has a function of calculating the distance between the driverless dump truck 10-1 and the driverless dump truck 10-2 based on the position information of the driverless dump truck 10-1 sent using the first radio bearer 201-1 and the position information of the driverless dump truck 10-2 sent using the first radio bearer 201-2, and performs proximity detection determination of the driverless dump truck 10-1 and the driverless dump truck 10-2 based on a predetermined proximity detection distance Y.

[0046] In the vehicle control server 31 located at the control station 30, as shown in Figure 5, if the distance X between vehicles determined from the position information of the unmanned dump truck 10-1 sent using the first wireless bearer 201-1 and the position information of the unmanned dump truck 10-2 sent using the first wireless bearer 201-2 is shorter than the proximity detection distance Y, and it is determined that the unmanned dump trucks 10-1 and 10-2 are in close proximity, the vehicle control server 31 will maintain the first wireless bearers 201-1 and 201-2 while newly establishing the second wireless bearers 202-1 and 202-2 for the unmanned dump trucks 10-1 and 10-2 that are in close proximity. The unmanned dump truck 10-1 transmits its own location information, acquired by the GPS receiving function of the on-board wireless terminal 1-1, to the vehicle control server 31 located at the control station 30 via the wireless base station 4, wireless relay station 5, and core network device 6 using the second wireless bearer 202-1. Similarly, the unmanned dump truck 10-2 transmits its own location information, acquired by the GPS receiving function of the on-board wireless terminal 1-2, to the vehicle control server 31 located at the control station 30 via the wireless base station 4, wireless relay station 5, and core network device 6 using the second wireless bearer 202-2. Furthermore, as shown in Figure 4 at time t3 (when there are no nearby vehicles), if the distance X between unmanned dump trucks 10-1 and 10-2 becomes longer than the proximity detection distance Y, the transmission of location information using the second wireless bearers 202-1 and 202-2 is stopped, and the second wireless bearers 202-1 and 202-2 are released, and only the transmission of location information using the first wireless bearers 201-1 and 201-2 continues, as at time t1. In the following, the first wireless bearers 201-1 and 201-2 and the second wireless bearers 202-1 and 202-2 may be collectively referred to as "first wireless bearer 201" and "second wireless bearer 202" without distinction.

[0047] FIG. 6 shows an example of the proximity detection distance Y between the driverless dump trucks 10. In this case, when referring to the driverless dump trucks 10, two driverless dump trucks 10 are assumed. One driverless dump truck 10 is regarded as the first vehicle, and the other driverless dump truck 10 is regarded as the second vehicle. For example, as shown in FIG. 6, the proximity detection distance Y is determined in advance based on the relative speed, height difference, presence or absence of embankment, and loading capacity between the vehicles (the first vehicle and the second vehicle). In the vehicle control and management server 31 arranged in the control station 30, when the relationship between the inter-vehicle distance X calculated based on the position information sent from each vehicle using the first radio bearers 201-1 and 201-2 and the proximity detection distance Y is such that the inter-vehicle distance X < the proximity detection distance Y, it is determined that the vehicles are in a proximity state. Regarding the relative speed between the vehicles, it may be obtained from the variation amount of the position information sent from the vehicles, or the traveling speed may be sent from each vehicle. For example, the greater the relative speed between the vehicles, the longer the proximity detection distance Y is set. Regarding the height difference between the vehicles, it may be obtained from the position information sent from the vehicles and the map information of the vehicle control and management server 31, or the altitude information may be sent from each vehicle. For example, the greater the height difference between the vehicles, the shorter the proximity detection distance Y is set. The embankment between the vehicles means whether there is an embankment serving as the median strip and guardrail on the general road between the vehicles. Regarding the embankment between the vehicles, it may be obtained from the position information sent from the vehicles and the map information of the vehicle control and management server 31, or the sensor information for detecting the embankment may be sent from each vehicle. For example, when there is an embankment between the vehicles, the proximity detection distance Y is set shorter than when there is no embankment between the vehicles. Also, the proximity detection distance Y may be changed according to the loading capacity of the driverless dump truck 10. The loading capacity between the vehicles can be, for example, the total of the loading capacities between the vehicles. For example, the greater the loading capacity between the vehicles, the longer the proximity detection distance Y is set.

[0048] Figure 7 shows an example of the proximity detection distance Y between an unmanned dump truck 10 and a manned vehicle 20. In this case, the unmanned dump truck 10 is considered the first vehicle and the manned vehicle 20 is considered the second vehicle. For example, as in Figure 6, the proximity detection distance Y is predetermined based on the relative speed, elevation difference, and presence or absence of an embankment between the vehicles (the first vehicle and the second vehicle). The vehicle control server 31 located at the control station 30 determines that the vehicles are in close proximity if the relationship between the vehicle distance X calculated based on the position information sent from each vehicle using the first wireless bearers 201-1 and 201-2 and the proximity detection distance Y is X < proximity detection distance Y. Although not shown in Figure 7, the proximity detection distance Y may also be changed according to the load capacity of the unmanned dump truck 10, as in Figure 6. The proximity detection distance Y between the unmanned dump truck 10 and the manned vehicle 20 is longer than the proximity detection distance Y between the two unmanned dump trucks 10, thus ensuring greater safety.

[0049] A feature of the present invention is that the first wireless bearer 201 and the second wireless bearer 202 have different priorities, with the priority of the second wireless bearer 202 being higher than that of the first wireless bearer 201. Furthermore, the transmission intervals for the location information of the unmanned dump truck 10 sent periodically using the first wireless bearer 201 and the location information of the unmanned dump truck 10 sent periodically using the second wireless bearer 202 are different, and the transmission interval for the location information of the unmanned dump truck 10 sent periodically using the second wireless bearer 202 is shorter than that for the location information of the unmanned dump truck 10 sent periodically using the first wireless bearer 201.

[0050] The characteristics of each wireless bearer are explained using Figure 8. Wireless bearer B1 is the fifth priority of the five types of wireless bearers and has the lowest priority. It has a transmission interval of 1000 ms, a position information resolution of 16 bits, and uses the UDP (User Data Protocol) protocol. It is mainly used for transmitting and receiving the position information of each vehicle under normal conditions and the driving control signals necessary for the autonomous driving of the unmanned dump truck 10. Wireless bearer B1 is the first wireless bearer 201 described above. Wireless bearer B2 is the second priority of the five types of wireless bearers. It has a transmission interval of 100 ms, a position information resolution of 32 bits, and uses the UDP protocol. It is mainly used for transmitting and receiving the position information of each vehicle in proximity and the driving control signals necessary for the autonomous driving of the unmanned dump truck 10. Wireless bearer B2 is the second wireless bearer 202 described above. Wireless bearer B3 has the highest priority among the five types of wireless bearers, with a transmission interval of 500 ms and using the UDP protocol. It is mainly used for sending and receiving emergency stop signals necessary for the emergency stop of the unmanned dump truck 10 in emergencies. Wireless bearer B4 has the third highest priority among the five types of wireless bearers, has no regular transmission interval, uses the TCP (Transmission Control Protocol) protocol, and is mainly used for sending and receiving instructions and commands necessary for the operation management of each vehicle. Wireless bearer B5 has the fourth highest priority among the five types of wireless bearers, has no regular transmission interval, uses the TCP protocol, and is mainly used for sending and receiving map data distribution to each vehicle. Note that Figure 8 illustrates five types of wireless bearers, but of course, there can be more or fewer than five types. The priority and transmission interval are merely examples.

[0051] Next, referring to Figure 9, the network load monitoring function, which is a feature of the vehicle control system 1000 according to the first embodiment of the present invention, will be described in detail. In the first embodiment of the present invention, the network load is monitored using location information packets from the unmanned dump truck 10 and the manned vehicle 20 that are periodically sent using a wireless bearer. Specifically, the network load is monitored by measuring the reception interval of the location information packets that are periodically sent. For example, assuming that the unmanned dump truck 10 and the manned vehicle 20 transmit location information packets at 1-second intervals, if the network load is in a normal state, as shown by the symbol (A) in Figure 9, the packet reception interval received by the vehicle control server 31 will also be approximately 1 second. On the other hand, as shown by the symbol (B) in Figure 9, if the network load is in an abnormal state (overloaded state), even if the unmanned dump truck 10 and the manned vehicle 20 transmit location information packets at 1-second intervals, delays and fluctuations will occur in the packet reception timing received by the vehicle control server 31, causing disturbances in the packet reception interval. Furthermore, if the network load increases, location information packets will be lost. Accordingly, the first embodiment of the present invention is characterized by monitoring the network load during operation by constantly monitoring the reception interval and loss of location information packets that are sent periodically.

[0052] Furthermore, in the first embodiment of the present invention, the wireless bearer used to monitor network load is the first wireless bearer 201 used by the unmanned dump truck 10 to transmit its own location information, that is, the wireless bearer B1 with the lowest priority among the five types of bearers in Figure 8. Due to the characteristics of mobile networks such as LTE, when the network becomes congested, packets with higher priority are given priority, so the wireless bearer B1 with the lowest priority is the first to be affected by network congestion. Therefore, by constantly monitoring the reception interval and loss of location information packets that are sent periodically using the wireless bearer B1 with the lowest priority, it becomes possible to sensitively monitor whether the network in operation is in an overloaded state.

[0053] Figure 10 shows the distribution of the probability of occurrence of the packet reception interval measured by the vehicle control server 31 when the unmanned dump truck 10 transmits its own position information at 1-second intervals using the first wireless bearer 201, i.e., the wireless bearer B1 with the lowest priority. When the network load is normal, the probability of occurrence of the packet reception interval is distributed with a small spread, i.e., a small standard deviation, centered around an average value of 1 second. On the other hand, when the network load is congested, the probability of occurrence of the packet reception interval remains at an average value of 1 second, but the spread of the probability distribution increases, i.e., the standard deviation increases. Furthermore, when the network load is overloaded, the spread of the probability distribution increases even further, i.e., the standard deviation becomes larger. Therefore, the first embodiment of the present invention is characterized by monitoring the network load using the spread of the probability distribution of the packet reception interval, i.e., the value of the standard deviation, as an indicator. For example, threshold judgments are made such as congestion when the standard deviation σ = 200 ms or more, and overload when it is 400 ms or more.

[0054] The following describes in detail the operation of the in-vehicle wireless terminal 2 of the first embodiment regarding the transmission of location information and emergency stop signals, with reference to the flowchart in Figure 11. The flowchart in Figure 11 is executed according to the timing period of the timer interrupt in the microcontroller device 103. For example, the timer value of the timer interrupt is set to 1000 ms. Note that the timer value can be changed arbitrarily.

[0055] The processing of the in-vehicle wireless terminal 2 begins at the timing of a timer interrupt in the microcontroller device 103 (step S001), and various parameters related to the wireless bearer stored in the storage device 802 of the microcontroller device 103 are set in the CPU 801 (step S002). The parameters related to the wireless bearer are, for example, the transmission interval, IP address, PORT number, etc. of the wireless bearers B1, B2, B3, B4, and B5 shown in Figure 8. The various parameters related to the wireless bearer stored in the storage device 802 of the microcontroller device 103 may also be updated as needed via a wireless link from the vehicle control server 31 through the wireless base station 4.

[0056] Next, after various parameters related to the wireless bearer are set, the in-vehicle wireless terminal 2 selects the wireless bearer B1 shown in Figure 8, i.e., the first wireless bearer 201 (step S003).

[0057] Next, the in-vehicle wireless terminal 2 acquires location information indicating the current location of the in-vehicle wireless terminal 2, that is, the current location of the manned vehicle 20, based on the GPS signals received using the GPS antenna 109 and GPS receiver 108 (step S004).

[0058] Next, the in-vehicle wireless terminal 2 proceeds to step S005, where it determines whether the emergency stop button 107 is pressed or not. If it determines that it is not pressed (No in step S005), the microcontroller device 103 generates an emergency stop signal "0" (step S006). On the other hand, if it determines that the emergency stop button 107 is pressed (Yes in step S005), the microcontroller device 103 generates an emergency stop signal "1" (step S007). Therefore, an emergency stop signal "1" indicates that the emergency stop button 107 has been pressed, and an emergency stop signal "0" indicates that the emergency stop button 107 has not been pressed.

[0059] Next, the in-vehicle wireless terminal 2 generates transmission data that includes location information indicating the current location of the manned vehicle 20 and an emergency stop signal ("0" or "1") (step S008). The generated transmission data is sent to the wireless modem 102 (step S009), and the timer interrupt processing is completed (step S010).

[0060] The wireless modem 102 receives the transmission data from the microcontroller device 103 and uses the wireless bearer B1 selected by the microcontroller device 103 to perform processing necessary for wireless communication, such as error correction coding, modulation, frequency conversion, amplification, and filtering, and then transmits a wireless signal from the transmitting / receiving antenna 101.

[0061] As the transmission operation is performed according to the flowchart in Figure 11, the location information of the manned vehicle 20 equipped with the vehicle-mounted wireless terminal 2 is periodically transmitted, and while the emergency stop button 107 is pressed (step S005: Yes), an emergency stop signal "1" is continuously transmitted. When the emergency stop button 107 is released (step S005: No), the microcontroller device 103 transmits an emergency stop signal of "0".

[0062] In addition, the vehicle-mounted wireless terminal 1 performs the same transmission operation as the vehicle-mounted wireless terminal 2, and the location information of the unmanned dump truck 10 on which the vehicle-mounted wireless terminal 1 is installed is transmitted periodically. This process excludes steps S005, S006, and S007 of the flowchart in Figure 11.

[0063] The following describes in detail the operation of transmitting location information and emergency stop signals in the vehicle-mounted wireless terminal 2 in proximity state, referring to the flowchart in Figure 12. The flowchart in Figure 12 is executed according to the timing period of the timer interrupt in the microcontroller device 103. For example, the timer value of the timer interrupt is set to 100 ms. Note that the timer value can be changed arbitrarily. Until the proximity state is reached, only wireless bearer B1, i.e., the first wireless bearer 201, is selected.

[0064] The processing of the in-vehicle wireless terminal 2 begins at the timing of a timer interrupt in the microcontroller device 103 (step S101), and various parameters related to the wireless bearer stored in the storage device 802 of the microcontroller device 103 are set in the CPU 801 (step S102). The parameters related to the wireless bearer are, for example, the transmission interval, IP address, PORT number, etc. of the wireless bearers B1, B2, B3, B4, and B5 shown in Figure 8. The various parameters related to the wireless bearer stored in the storage device 802 of the microcontroller device 103 may also be updated as needed via a wireless link from the vehicle control server 31 through the wireless base station 4.

[0065] Next, the in-vehicle wireless terminal 2 proceeds to step S103, where it performs an operation based on the proximity detection information sent from the vehicle control server 31. After various parameters related to the wireless bearer are set, if the value of the proximity detection information sent from the vehicle control server 31 is "0" (No in step S103), the timer interrupt processing is completed (step S105). On the other hand, if the value of the proximity detection information is "1" (Yes in step S103), the wireless bearer B2 shown in Figure 8, i.e., the second wireless bearer 202, is additionally selected (step S104).

[0066] Next, the vehicle-mounted wireless terminal 2 acquires location information indicating the current position of the vehicle-mounted wireless terminal 2, i.e., the current position of the manned vehicle 20, based on the GPS signal received using the GPS antenna 109 and GPS receiver 108 (step S106). The resolution of the location information indicating the current position of the manned vehicle 20 acquired here may be higher than the resolution of the location information acquired by the wireless bearer B1 in Figure 11. By increasing the resolution of the location information sent by the second wireless bearer 202 compared to the location information sent by the first wireless bearer 201, more precise vehicle control of the unmanned dump truck 10 becomes possible, resulting in increased productivity, such as a shorter deceleration period. Here, the resolution of the location information refers to the number of bits; for example, the location information sent by the first wireless bearer 201 is 16 bits, and the location information sent by the second wireless bearer 202 is 32 bits.

[0067] Next, the in-vehicle wireless terminal 2 proceeds to step S107, where it determines whether the emergency stop button 107 is pressed or not. If it determines that it is not pressed (No in step S107), the microcomputer device 103 generates an emergency stop signal "0" (step S108). On the other hand, if it determines that the emergency stop button 107 is pressed (Yes in step S107), the microcomputer device 103 generates an emergency stop signal "1" (step S109). Therefore, an emergency stop signal "1" indicates that the emergency stop button 107 has been pressed, and an emergency stop signal "0" indicates that the emergency stop button 107 has not been pressed.

[0068] Next, the in-vehicle wireless terminal 2 generates transmission data that includes location information indicating the current location of the manned vehicle 20 and an emergency stop signal ("0" or "1") (step S110). The generated transmission data is sent to the wireless modem 102 (step S111), and the timer interrupt processing is completed (step S112).

[0069] The wireless modem 102 processes the transmission data received from the microcontroller device 103 using a wireless bearer selected by the microcontroller device 103, performing necessary processing for wireless communication such as error correction coding, modulation, frequency conversion, amplification, and filtering, and then transmits a wireless signal from the transmitting / receiving antenna 101.

[0070] As the transmission operation is performed according to the flowchart in Figure 12, the location information of the manned vehicle 20 equipped with the vehicle-mounted wireless terminal 2 is periodically transmitted, and while the emergency stop button 107 is pressed (step S107: Yes), an emergency stop signal "1" is continuously transmitted. When the emergency stop button 107 is released (step S107: No), the microcontroller device 103 transmits an emergency stop signal of "0".

[0071] In addition, the vehicle-mounted wireless terminal 1 performs the same transmission operation as the vehicle-mounted wireless terminal 2, and the location information of the unmanned dump truck 10 on which the vehicle-mounted wireless terminal 1 is installed is transmitted periodically. This process excludes steps S107, S108, and S109 of the flowchart in Figure 12.

[0072] The operation of the in-vehicle wireless terminal 1 in receiving driving control signals and emergency stop signals will be explained in detail below with reference to the flowchart in Figure 13. The flowchart in Figure 13 is executed according to the timing period of the timer interrupt in the microcontroller device 103. For example, the initial value of the timer interrupt timer is set to 1000 ms. Note that the timer value can be changed arbitrarily.

[0073] The vehicle-mounted wireless terminal 1 receives wireless signals from the transmitting and receiving antenna 101, and the wireless modem 102 performs necessary processing for wireless communication, such as filtering, amplification, frequency conversion, demodulation, and error correction decoding.

[0074] The processing of the in-vehicle wireless terminal 1 begins at the timing of a timer interrupt in the microcontroller device 103 (step S201), and various parameters related to the wireless bearer stored in the storage device 802 of the microcontroller device 103 are set in the CPU 801 (step S202). These various parameters related to the wireless bearer include, for example, the transmission interval, IP address, and PORT number of the wireless bearers B1, B2, B3, B4, and B5 shown in Figure 8. The various parameters related to the wireless bearer stored in the storage device 802 of the microcontroller device 103 may also be updated as needed via a wireless link from the vehicle control server 31 through the wireless base station 4.

[0075] Next, the in-vehicle wireless terminal 1 proceeds to step S203, where it operates based on proximity detection information sent from the vehicle control server 31. After various parameters related to the wireless bearer are set, if the value of the proximity detection information sent from the vehicle control server 31 is "0" (No in step S203), the timer value is set to 1000ms (step S204), and the wireless bearer B1 shown in Figure 8, i.e., the first wireless bearer 201, is selected (step S205). On the other hand, if the value of the proximity detection information is "1" (Yes in step S203), the timer value is set to 100ms (step S206), and the wireless bearer B2 shown in Figure 8 is selected (step S207).

[0076] Next, the in-vehicle wireless terminal 1 acquires the driving control signals necessary for the autonomous driving of the unmanned dump truck 10, the emergency stop signals necessary for the emergency stop of the unmanned dump truck 10, and the reception time of the received packets, all of which are included in the received data of the selected wireless bearer (step S208).

[0077] Next, the in-vehicle wireless terminal 1 proceeds to step S209, where it measures the packet reception interval from the difference between the packet reception time of the previously received data and the packet reception time of the currently received data, and determines whether this measured packet reception interval exceeds a predetermined interruption time.

[0078] If it is determined that the measured packet reception interval does not exceed a predetermined interruption time (No in step S209), the microcontroller device 103 generates an interruption determination signal "0" (step S210). On the other hand, if it is determined that the communication interval exceeds a predetermined interruption time (Yes in step S209), the microcontroller device 103 generates an interruption determination signal "1" (step S211). An interruption determination signal "1" means that wireless communication has been interrupted for a predetermined time or longer.

[0079] Next, the vehicle-mounted wireless terminal 1 generates control data including the obtained interruption determination signal ("0" or "1"), driving control signals necessary for the autonomous driving of the unmanned dump truck 10 (such as driving permission and speed command), and an emergency stop signal necessary for the emergency stop of the unmanned dump truck 10 (step S212). The generated control data is converted to the voltage and protocol required by the external device via the external I / F 104 and transmitted to the external device (step S213), completing the timer interrupt processing (step S214). The external device is, for example, a vehicle-mounted controller device or a BCU (Brake Control Unit) installed on the unmanned dump truck 10. Based on the control data output from the external I / F 104 to the external device, the unmanned dump truck 10 performs processes such as autonomous driving based on the driving control signals and emergency stopping based on the emergency stop signals.

[0080] Referring to the flowchart in Figure 14, the operation of proximity detection using location information in the vehicle control server 31 will be explained in detail. The flowchart in Figure 14 is executed continuously by the operating clock of the vehicle control server 31. Note that the vehicle control server 31 is composed of a general-purpose server, so the hardware configuration will be omitted.

[0081] The processing of the vehicle control server 31 is performed continuously and periodically according to the operating clock of the vehicle control server 31 (step S301), and the transmitted data sent from each vehicle becomes the received data for the vehicle control server 31 and is stored in memory as it occurs.

[0082] The vehicle control server 31 acquires received data for all vehicles, including location information indicating the current position of each vehicle, an emergency stop signal ("0" or "1"), and the time of reception of the received packet (step S302).

[0083] Next, the vehicle control server 31 measures the packet reception interval for each vehicle from the difference between the reception time of the previously received packet and the reception time of the currently received packet, and uses the measured packet reception interval to calculate the standard deviation, i.e., ((measured value) - (average value)). ２ Find the positive square root of (step S303).

[0084] Next, the vehicle control server 31 proceeds to step S304. If the calculated standard deviation does not exceed the first threshold (for example, 200 ms), it proceeds to step S308. If it is determined that it exceeds the threshold, it proceeds to step S305.

[0085] Next, if the vehicle control server 31 does not exceed the second threshold (for example, 400 ms) calculated in step S305, it proceeds to step S306 and notifies the monitor at the control station 30 that the network load is congested.

[0086] On the other hand, if the calculated standard deviation in step S305 exceeds the second threshold (for example, 400 ms), the process proceeds to step S307, and the control station 30 notifies the monitor that the network load is in an overloaded state.

[0087] Next, the vehicle control server 31 performs proximity detection on all vehicles based on the location information contained in the received data sent from each vehicle (step S308).

[0088] Regarding the proximity detection determination method, as explained with reference to Figures 4 and 5, for example, if the relationship between the distance X obtained from the position information of unmanned dump truck 10-1 and the position information of unmanned dump truck 10-2 and the predetermined proximity detection distance Y is such that the distance between vehicles X < proximity detection distance Y, then it is determined that unmanned dump truck 10-1 and unmanned dump truck 10-2 are in close proximity.

[0089] The vehicle control server 31 then proceeds to step S309, and based on the proximity detection determination results between all vehicles performed using the position information contained in the received data of each vehicle, if a vehicle is not determined to have any vehicles nearby (No in step S309), it sets the proximity detection information to "0" (step S310) and selects only the wireless bearer B1, i.e., the first wireless bearer 201 (step S311). On the other hand, if a vehicle is determined to have vehicles nearby (Yes in step S309), it sets the proximity detection information to "1" (step S312) and selects wireless bearers B1 and B2, i.e., the first wireless bearer 201 and the second wireless bearer 202 (step S313).

[0090] The vehicle control server 31 then generates transmission data including proximity detection information ("0" or "1") and an emergency stop signal (step S314). The generated transmission data is periodically transmitted to the vehicle-mounted wireless terminals 1 and 2 installed on the target unmanned dump truck 10 and manned vehicle via the core network device 6, wireless relay station 5, wireless relay line 510, and each wireless base station 4 using the selected wireless bearer (step S315). Here, periodic data transmission means, for example, that the transmission interval is 1000 ms for wireless bearer B1 and 100 ms for wireless bearer B2. Once data transmission is complete, the process ends (step S316). Then, it returns to START (S301) and the same operation is repeated.

[0091] [Second Embodiment] The operation of proximity detection using location information in the vehicle control server 31 in the second embodiment of the present invention will be described in detail below with reference to the flowchart in Figure 15. The same processing as in steps S301 to S304 in Figure 14 is also performed in steps S401 to S404 in Figure 15. In step S404, if the vehicle control server 31 determines that the calculated standard deviation exceeds a first threshold (for example, 200 ms), the network load is congested. Therefore, in order to avoid increasing the network load, the selection of wireless bearer B2, i.e., the second wireless bearer 202, is not performed, and the flow may proceed to step S410 after performing the processing in steps S405 to S407, similar to steps S305 to S307 in Figure 14. In this case, communication is performed only by wireless bearer B1, i.e., the first wireless bearer 201. Subsequently, the same processing as in steps S308 to S316 in Figure 14 is performed in steps S408 to S416 in Figure 15. In the flowchart of Figure 15, if it is determined in step S404 that the calculated standard deviation exceeds a threshold greater than the first threshold (for example, 400 ms), the network load is in an overload state (overload). Similarly, in order to avoid increasing the network load, the selection of wireless bearer B2 is not performed, and communication is performed only with wireless bearer B1, i.e., the first wireless bearer 201. According to the second embodiment, it is avoided to further increase the network load when the network load is in an overload state.

[0092] [Third Embodiment] The operation of proximity detection using location information in the vehicle control server 31 in the third embodiment of the present invention will be described in detail below with reference to the flowchart in Figure 16. The same processing as in steps S401 to S405 in Figure 15 is performed in steps S501 to S505 in Figure 16. In step S505, if the vehicle control server 31 determines that the calculated standard deviation exceeds a second threshold (for example, 400 ms) which is greater than the first threshold, the network load is in an overloaded state (overload), and therefore the vehicle control system 1000 is in a dangerous state. Therefore, after performing the same processing as in step S407 in Figure 15, the vehicle control server 31 may perform an operation to completely stop the unmanned dump truck 10 and to perform an emergency stop of the entire vehicle control system 1000 (step S517). The same process as in steps S405 to S406 and S408 to S416 in Figure 15 is also performed in steps S505 to S506 and S508 to S516 in Figure 15. According to the third embodiment, if the network load is in an overload state and the vehicle control system 1000 is in a dangerous state, the entire vehicle is stopped and the entire vehicle control system 1000 is stopped in an emergency, thereby improving safety.

[0093] As described above with reference to Figures 14 to 16, in the first to third embodiments of the present invention, the decision to add the second wireless bearer 202 to the first wireless bearer 201 is mainly made by the vehicle control server 31. However, as described above with reference to Figures 12 and 13, the decision to add the second wireless bearer 202 to the first wireless bearer 201 may also be made by the in-vehicle wireless terminal 1 and the in-vehicle wireless terminal 2.

[0094] As described above, according to the first to third embodiments of the present invention, a vehicle control system 1000 can be provided that does not have the degradation of wireless quality specific to inter-vehicle communication, and does not increase the probability of equipment failure because multiple wireless terminals are not installed in each vehicle, thereby improving the safety and productivity of the vehicle.

[0095] In the first to third embodiments of the present invention, the vehicle control system 1000 controls an unmanned dump truck 10. However, the autonomous vehicles controlled by the vehicle control system 1000 are not limited to the unmanned dump truck 10. Other vehicles may also be controlled, and the same control may be performed on them as on the unmanned dump truck 10.

[0096] It should be noted that the present invention is not limited to the embodiments described above, and various modifications are included. For example, the embodiments described above are described in detail to make the present invention easier to understand, and are not necessarily limited to those having all the configurations described. Furthermore, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace parts of the configuration of each embodiment with other configurations. In addition, some or all of the above configurations, functions, processing units, processing means, etc., may be implemented in hardware, for example by designing them as integrated circuits, or they may all be implemented in software.

[0097] 1...Vehicle-mounted wireless terminal, 2...Vehicle-mounted wireless terminal, 4...Wireless base station, 5...Wireless relay station, 6...Core network device, 10...Unmanned dump truck, 20...Manned vehicle, 30...Control station, 31...Vehicle control server, 100...Transportation path, 101...Transmitting / receiving antenna, 102...Wireless modem, 103...Microcontroller device, 104...External I / F, 105...Power supply device, 106...Display device, 107...Emergency stop button, 108...GPS receiver, 109...GPS antenna, 200...Loading area, 201...First wireless bearer, 202...Second wireless bearer, 300...Unloading area, 510...Wireless relay line, 801...CPU, 802...Memory device, 810...Battery, 811...Voltage converter, 1000...Vehicle control system, B1, B2, B3, B4, B5...Wireless bearer

Claims

1. A vehicle control system comprising: a wireless terminal mounted on each of a first vehicle and a second vehicle and capable of communicating with a base station; and a vehicle control server device located in a control station that communicates with the wireless terminals via the base station, wherein the vehicle control server device determines whether the first vehicle and the second vehicle are in close proximity to each other based on the location information of each of the first vehicle and the second vehicle transmitted via the base station using a first communication line from the wireless terminals mounted on the first vehicle and the second vehicle, and if it is determined that they are in close proximity, it transmits and receives the location information of each of the first vehicle and the second vehicle via the base station using a second communication line, wherein the first communication line and the second communication line are different first and second wireless bearers, even though they are on the same wireless channel with respect to the wireless terminals, and the first and second wireless bearers have different communication priorities.

2. A vehicle control system according to claim 1, characterized in that the communication priority of the second wireless bearer is higher than the communication priority of the first wireless bearer.

3. A vehicle control system according to claim 2, characterized in that the transmission interval of the second wireless bearer is shorter than the transmission interval of the first wireless bearer.

4. A vehicle control system according to claim 3, characterized in that the position information transmitted by the first wireless bearer and the position information transmitted by the second wireless bearer have a higher resolution in the position information transmitted by the second wireless bearer than in the position information transmitted by the first wireless bearer.

5. A vehicle control system according to claim 1, characterized in that the distance at which the system determines whether the first vehicle and the second vehicle are in close proximity to each other, based on the position information of the first vehicle and the second vehicle transmitted via the base station using the first wireless bearer, is varied according to the relative speed, elevation difference, presence or absence of an embankment, and load capacity of the first vehicle and the second vehicle.

6. A vehicle control system according to claim 5, characterized in that the greater the relative speed of the first vehicle and the second vehicle, the longer the distance for determining whether the first vehicle and the second vehicle are in close proximity to each other is set; the greater the difference in elevation between the first vehicle and the second vehicle, the shorter the distance for determining whether the first vehicle and the second vehicle are in close proximity to each other is set; when there is an embankment between the first vehicle and the second vehicle, the shorter the distance for determining whether the first vehicle and the second vehicle are in close proximity to each other is set compared to when there is no embankment between the first vehicle and the second vehicle; and the greater the load capacity of the first vehicle and the second vehicle, the longer the distance for determining whether the first vehicle and the second vehicle are in close proximity to each other is set.

7. A vehicle control system according to claim 6, characterized in that when the first vehicle and the second vehicle are an unmanned vehicle and a manned vehicle, the distance for determining whether the first vehicle and the second vehicle are close to each other is set to be longer than when the first vehicle and the second vehicle are both unmanned vehicles.

8. A vehicle control system according to claim 1, wherein the vehicle control server device has a function of monitoring network load based on the packet reception interval of the position information of the first vehicle and the second vehicle transmitted from the wireless terminals mounted on the first vehicle and the second vehicle via the base station using the first wireless bearer.

9. A vehicle control system according to claim 8, wherein the vehicle control server device monitors the network load using the standard deviation of the probability of occurrence of the packet reception interval of the position information of the first vehicle and the second vehicle transmitted from the wireless terminal mounted on the first vehicle and the second vehicle via the base station using the first wireless bearer as an indicator, and determines that the network load is overloaded when the standard deviation exceeds a predetermined threshold.

10. A vehicle control system according to claim 9, wherein the vehicle control server device monitors the network load based on the packet reception interval of the position information of the first vehicle and the second vehicle transmitted from the wireless terminals mounted on the first vehicle and the second vehicle via the base station using the first wireless bearer, and notifies the monitor at the control station when the network load is determined to be overloaded.

11. A vehicle control system according to claim 9, wherein the vehicle control server device monitors the network load based on the packet reception interval of the position information of the first vehicle and the second vehicle transmitted via the base station using the first wireless bearer from the wireless terminals mounted on the first vehicle and the second vehicle, and when the network load is determined to be overloaded, the second wireless bearer is not used and communication is performed using only the first wireless bearer.

12. A vehicle control system according to claim 9, wherein the vehicle control server device monitors the network load based on the packet reception interval of the position information of the first vehicle and the second vehicle transmitted from the wireless terminals mounted on the first vehicle and the second vehicle via the base station using the first wireless bearer, and when the network load is determined to be overloaded, it executes the process of stopping the first vehicle and the second vehicle and stopping the entire vehicle control system.

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