Construction machine control system, construction machine, construction machine management system, and construction machine control method and program

A construction machine control system for a construction machine that travels along a travel route, includes: a position detection unit that detects a position of the construction machine; a determination unit that determines whether an error in the position detected by the position detection unit is equal to or smaller than a predetermined error; a non-contact sensor that detects a position of an object around the construction machine; and a map information storage unit that extracts a detection result related to a vertical projection that protrudes vertically from a detection result of the non-contact sensor and stores the extracted detection result related to the vertical projection as map information when the determination unit determines that the error in the position detected by the position detection unit is equal to or smaller than the predetermined error.

FIELD

The present invention relates to a construction machine control system, a construction machine, a construction machine management system, and a construction machine control method and program.

BACKGROUND

Mining machines as a construction machine such as a dump truck as disclosed in Patent Literature 1 operate in an excavation site of a mine.

CITATION LIST

Patent Literature

SUMMARY

Technical Problem

A construction machine that travels autonomously along a travel route in a mine may stop its operation when the accuracy of the position detected using a global navigation satellite system decreases due to an abnormality in the ionosphere. As a result, the productivity of a mine may decrease.

An object of the present invention is to provide a construction machine control system, a construction machine, a construction machine management system, and a construction machine control method and program.

Solution to Problem

According to the present invention, a construction machine control system for a construction machine that travels along a travel route, comprises: a position detection unit that detects a position of the construction machine; a determination unit that determines whether an error in the position detected by the position detection unit is equal to or smaller than a predetermined error; a non-contact sensor that detects a position of an object around the construction machine; and a map information storage unit that extracts a detection result related to a vertical projection that protrudes vertically from a detection result of the non-contact sensor and stores the extracted detection result related to the vertical projection as map information when the determination unit determines that the error in the position detected by the position detection unit is equal to or smaller than the predetermined error.

In the present invention, it is preferable that the map information storage unit stops storing the map information when a stopped state of the construction machine is detected.

In the present invention, it is preferable that the construction machine control system further comprises: a position measurement unit that specifies the position of the construction machine by comparing the detection result of the non-contact sensor and the map information stored by the map information storage unit when the determination unit determines that the error in the position detected by the position detection unit exceeds the predetermined error.

In the present invention, it is preferable that the position measurement unit stops specifying the position of the construction machine by comparing the detection result of the non-contact sensor and the map information stored by the map information storage unit when a stopped state of the construction machine is detected.

In the present invention, it is preferable that when the determination unit determines that the error in the position detected by the position detection unit is equal to or smaller than the predetermined error, the position measurement unit compares the detection result of the non-contact sensor and the map information stored by the map information storage unit to specify the position of the construction machine and determines whether it is appropriate to allow the construction machine to travel along the travel route based on the position of the construction machine specified by the position measurement unit.

In the present invention, it is preferable that when the determination unit determines that the error in the position detected by the position detection unit is equal to or smaller than the predetermined error, the position measurement unit detects and stores a distance between the position detected by the position detection unit and the position of the construction machine obtained by comparing the detection result of the non-contact sensor and the map information of the travel route stored by the map information storage unit.

According to the present invention, a construction machine comprises: the construction machine control system; and a vehicle body that travels along a travel route provided in a mine.

According to the present invention, a construction machine management system comprises: the construction machine; and a management device that is disposed in a control facility provided in a mine and transmits information on a travel route provided in the mine to a construction machine control system of the construction machine.

According to the present invention, a construction machine control method for controlling a construction machine that travels along a travel route, comprises: allowing the construction machine to travel along the travel route based on a position of the construction machine detected using a position detection unit; extracting a detection result related to a vertical projection that protrudes vertically from a detection result of a non-contact sensor that detects a position of an object around the construction machine when an error in the detected position of the construction machine is equal to or smaller than a predetermined error; and storing the extracted detection result related to the vertical projection as map information of the travel route.

According to the present invention, provided is a program for causing a computer provided in a construction machine that travels along a travel route provided in a mine based on a position detected using a position detection unit to execute: determining whether an error in the position of the construction machine detected using the position detection unit is equal to or smaller than a predetermined error; and extracting a detection result related to a vertical projection from a detection result of a non-contact sensor that detects a position of an object around the construction machine when it is determined that the error in the detected position is equal to or smaller than the predetermined error and storing the extracted detection result related to the vertical projection in a map information storage unit as map information of the travel route.

According to the present invention, a decrease in the productivity of a mine is suppressed.

DESCRIPTION OF EMBODIMENTS

While embodiments of the present invention will be described with reference to the drawings, the present invention is not limited to these embodiments.

First Embodiment

<Overview of Construction Machine Management System>

FIG. 1is a diagram illustrating an example of a construction machine management system according to a first embodiment.

A construction machine management system1(hereinafter referred to as a management system) includes a management device10disposed in a control facility7and manages construction machines. Management of construction machines includes at least one of operations control of construction machines, the evaluation of productivity of the construction machines, the evaluation of operation skill of the construction machine operators, the maintenance of the construction machines, and the abnormality diagnosis of the construction machines.

The construction machine is a generic name of machinery used for various operations at a mine. Construction machines include at least one of a boring machine, an excavating machine, a loading machine, a transport machine, a crushing machine, and a vehicle that is driven by an operator. The excavating machines can excavate a mine. The loading machines can load loads the transport machine. The loading machines include at least one of an excavator, an electric shovel, and a wheel loader. The transport machine includes a moving body that can move at a mine, and can transport a load. The transport machines include a dump truck. The loads include at least one of soil and ores produced by excavation. The crushing machines crushes the dumped earth unloaded from the transport machines.

In the first embodiment, transport machines which are construction machines that travel in a mine are managed by the management system1. In the first embodiment, an example in which dump trucks2which are the construction machines are managed by the management system1will be described. The dump truck2is a mining machine used in a mine and operates on at least a portion of a loading area LPA in a mine, a dumping area DPA, a haul road HL that leads to at least one of the loading area LPA and the dumping area DPA, and an intersection IS at which the haul roads HL cross each other as illustrated inFIGS. 1 and 2. A crushing machine CR that crushes the dumped earth may be disposed in at least one dumping area DPA. A bank BK in which earth is piled is provided in at least one of the outside of the loading area LPA, the outside of the dumping area DPA, and the outside of the haul road HL.

The dump truck2is a moving object that can move in a mine. The dump truck2can travel on at least a portion of the loading area LPA, the dumping area DPA, the haul road HL, and the intersection IS. The dump truck2can travel on at least a portion of the haul road HL and the intersection IS and can move between the loading area LPA and the dumping area DPA. That is, a travel route RP of the dump truck2provided in a mine includes at least a portion of the loading area LPA, the dumping area DPA, the haul road HL, and the intersection IS. Vertical projections VP that protrude by a predetermined height vertically from the surface of the travel route RP are disposed in a mine. In the first embodiment, the vertical projections VPs include the bank BK, an artificial object AF provided in at least one of the loading area LPA, the dumping area DPA, and the haul road HL, and a wall WL provided in at least one of the LPA, the dumping area DPA, and the haul road HL. However, the vertical projection VP may include signs, artificial objects such as a building, rocks, and the like. However, the vertical projection VP is not limited to this. The predetermined height is such a height that it is not desirable for the dump truck2to run over the vertical projection VP during autonomous travel.

The dump truck2can load loads in the loading area LPA. The loading area LPA is an area (place) where an operation of loading a load is performed in a mine. In the loading area LPA, a loading machine which is another construction machine3other than the dump truck2loads a load on the dump truck2.

The dump truck2unloads (discharges) loads in the dumping area DPA. The dumping area DPA is an area (place) where an operation of discharging a load in a mine is performed. The dump truck2puts the dumped earth which is a load into a crushing machine CR in the dumping area DPA in which the crushing machine CR is provided.

In the first embodiment, the dump truck2is a so-called unmanned dump truck that generally autonomously travels along the travel route RP according to an instruction signal from a management device10. The dump truck2does not travel according to an operation of an operator (driver). The dump truck2travelling autonomously unit that the dump truck2does not travel according to an operation of an operator but travels according to an instruction signal from the management device10.

InFIG. 1, the management system1includes the management device10disposed in a control facility7to manage the dump truck2, a communication system9capable of transmitting information, the dump truck2, and the other construction machine3.

The management device10is installed in the control facility7of the mine. The control facility7may be referred to as a management facility7or a central control room7. The management device10may be referred to as a control device (central control device)10or a central control system10. The management device10does not move. The management device10may be movable.

The communication system9delivers information according to wireless communication among the management device10, the dump truck2, and the other construction machine3. The management device10and the dump truck2can perform bidirectional wireless communication via the communication system9. The management device10and the other construction machine3can perform bidirectional wireless communication via the communication system9. The dump truck2and the other construction machine3can perform bidirectional wireless communication via the communication system9. In the first embodiment, the communication system9includes a plurality of relays6that relays signals (radio waves) among the management device10, the dump truck2, and the other construction machine3.

In the first embodiment, the positions of the dump truck2and the other construction machine3are detected using a real time kinematic-global navigation satellite systems (RTK-GNSS; GNSS means global navigation satellite system). An example of the global navigation satellite system is a global positioning system (GPS) but not limited to this. The RTK-GNSS includes a plurality of positioning satellites5. The RTK-GNSS detects a position in a coordinate system (a global coordinate system) that defines latitude, longitude, and altitude. The position detected by the RTK-GNSS includes coordinate data of latitude, longitude, and altitude. The positions of the dump truck2and the other construction machine3in a mine are detected by the RTK-GNSS. The positions detected by the RTK-GNSS are absolute positions defined in the global coordinate system. In the following description, the positions detected by the RTK-GNSS will be appropriately referred to as GPS positions. The GPS positions are absolute positions and are coordinate data (coordinate values) of latitude, longitude, and altitude. Moreover, according to the RTK-GNSS, a positioning state changes due to the influence of an arrangement of the positioning satellites5, the ionosphere, the troposphere, or the geographical features around an antenna that received information from the positioning satellite5. Examples of the positioning state include Fix solution (accuracy: approximately ±1 cm to 2 cm), Float solution (accuracy: approximately ±10 cm to several meters), Single solution (accuracy: approximately ± several meters), and No solution (Unable to compute a solution).

Moreover, the management system1manages the positions of the dump truck2and the other construction machine3in a mine using coordinates (hereinafter referred to as X-Y coordinates) defined in an X-axis direction and a Y-axis direction orthogonal to each other illustrated inFIG. 1. Moreover, the management system1manages the directions of the dump truck2and the other construction machine3using the North as 0°, the East as 90°, the South as 180°, and the West as 270°. The directions of the dump truck2and the other construction machine3are the directions in which the dump truck2and the other construction machine3move when travelling forward. In the first embodiment, although the Y-axis direction indicates the North, the present invention is not limited to this.

Next, the management device10disposed in the control facility7will be described. The management device10is configured to transmit information on the travel route RP provided in a mine to a construction machine control system30of the dump truck2. As illustrated inFIG. 1, the management device10includes a computer11, a display device16, an input device17, a wireless communication device18, and a GPS base station19.

The computer11includes a processing device12, a storage device13, and an input and output unit15. The display device16, the input device17, the wireless communication device18, and the GPS base station19are connected to the computer11via the input and output unit15. The input and output unit15is used for inputting and outputting (interfacing) information to and from at least one of the processing device12, the display device16, the input device17, the wireless communication device18, and the GPS base station19.

The processing device12executes various processes related to the management of the dump truck2and the other construction machine3. The processing device12processes the information on the positions of the dump truck2and the other construction machine3, acquired via the communication system9. The processing device12generates information on the travel route RP of the dump truck2.

The storage device13is connected to the processing device12. The storage device13stores various items of information related to the management of the dump truck2and the other construction machine3. The storage device13stores the positions of the dump truck2and the other construction machine3. The storage device13stores a computer program for causing the processing device12to execute various processes.

The display device16includes a flat panel display such as a liquid crystal display, for example. The display device16can display information on the positions of the dump truck2and the other construction machine3.

The input device17includes at least one of a keyboard, a touch panel, and a mouse. The input device17functions as an operating unit that can input an operation signal to the processing device12. An administrator of the control facility7can operate the input device17to input an operation signal to the processing device12.

The wireless communication device18is disposed in the control facility7. The wireless communication device18is a portion of the communication system9. The wireless communication device18is connected to the processing device12via the input and output unit15. The wireless communication device18has an antenna18A. The wireless communication device18can receive information transmitted from at least one of the dump truck2and the other construction machine3. The information received by the wireless communication device18is output to the processing device12and is stored (registered) in the storage device13. The wireless communication device18can transmit information to at least one of the dump truck2and the other construction machine3.

The GPS base station19is disposed in the control facility7. The GPS base station19includes an antenna19A that receives information from the plurality of positioning satellites5and a transceiver19B connected to the antenna19A. The transceiver19B includes at least a receiver that receives information from the positioning satellite5via the antenna19A, a transmitter that transmits information to the dump truck2via an antenna19C, an arithmetic processor that includes a microprocessor such as a central processing unit (CPU), and a storage device that includes a memory such as read only memory (ROM) or random access memory (RAM). The transceiver19B detects the GPS position of the GPS base station19from the information received by the antenna19A and correction measurement information for correcting the GPS position of the dump truck2. The transceiver19B of the GPS base station19transmits the correction measurement information to the dump truck2and the other construction machine3via the antenna19C.

The computer11includes at least a communication input and output unit15, a central processing unit (CPU) that executes a control program, read only memory (ROM) that stores the control program, random access memory (RAM) that is used as a work area of the CPU, and nonvolatile memory in which information is registered by the CPU.

The function of the processing device12is realized when the CPU reads the control program stored in the ROM and executes the control program in the work area of the RAM. The function of the storage device13is realized when the ROM stores the control program and the information is stored in the nonvolatile memory by the CPU. The nonvolatile memory includes at least one of flash memory and a hard disk and realizes a database. Moreover, a plurality of processing circuits may realize the functions of the processing device12and the storage device13in collaboration.

Next, the other construction machine3will be described. In the first embodiment, the other construction machine3is a construction machine other than the dump truck2and is driven by the operation of the operator. The other construction machine3includes a processing device that includes a central processing unit (CPU) and executes various processes related to operation content, a GPS receiver that detects the GPS position, and a wireless communication device that transmits and receives information to and from the wireless communication device18of the control facility7. The wireless communication device of the other construction machine3transmits a GPS position to the wireless communication device18of the control facility7every predetermined period.

Next, the dump truck2will be described.FIG. 2is a control block diagram of the dump truck according to the first embodiment.FIG. 3is a hardware configuration diagram of the dump truck according to the first embodiment.FIG. 4is a front view of an obstacle sensor of the dump truck according to the first embodiment.FIG. 5is a plan view illustrating a detection range of a laser sensor of the obstacle sensor illustrated inFIG. 4.FIG. 6is a side view illustrating the detection range of the laser sensor of the obstacle sensor of the dump truck illustrated inFIG. 4.

As illustrated inFIG. 3, the dump truck2includes a vehicle body21, a vessel22, wheels23, an obstacle sensor24, and a construction machine control system30.

The vehicle body21is configured to travel along the travel route RP. An internal combustion engine2E such as a diesel engine, a generator2G operated by the internal combustion engine2E, and a motor23M operated by the electric power generated by the generator2G are disposed in the vehicle body21. Rear wheels23R of the wheels23are driven by the motor23M. The power of the internal combustion engine2E may be transmitted to the rear wheels23R via a transmission including a torque converter. Moreover, the vehicle body21includes a steering device2S that steers front wheels23F of the wheels23. A loading machine loads a load on the vessel22and the vessel is lifted during a discharge operation to discharge the load.

As illustrated inFIG. 4, the obstacle sensor24is disposed under the front portion of the vehicle body21. The obstacle sensor24detects an obstacle in front of the vehicle body21in a non-contacting manner. In the first embodiment, as illustrated inFIG. 4, the obstacle sensor24includes a plurality of radars24A which is a non-contact sensor and a laser sensor24B which is a non-contact sensor. The radar24A is configured to detect the position of an object around the dump truck2. The radar24A emits radio waves to irradiate an obstacle with the radio waves and receives radio waves reflected from the obstacle. In this way, the radar24A can detect the direction and the distance of the obstacle in relation to the radar24A. In the first embodiment, although three radars24A are provided at intervals in the left-right direction of the vehicle body21, the present invention is not limited to this.

The laser sensor24B is configured to detect the position of an object around the dump truck2. The laser sensor24B emits a laser beam to irradiate an obstacle which is an object with the laser beam and receives a laser beam reflected from the obstacle. In this way, the laser sensor24B can detect the direction and the distance of the obstacle in relation to the laser sensor24B. The resolution of the laser sensor24B is higher than the resolution of the radar24A because the laser sensor24B emits a laser beam and receives the reflected laser beam. In the first embodiment, as illustrated inFIG. 4, although two laser sensors24B are provided at an interval in the left-right direction of the vehicle body21, the present invention is not limited to this.

The laser sensor24B allows laser beams to oscillate in the left-right direction while emitting four laser beams having different directions in the up-down direction and receives laser beams reflected by an obstacle. In the first embodiment, although the two laser sensors24B are configured such that the irradiation area IAH of laser beams overlap at the center in the left-right direction in a plan view of the vehicle body21as illustrated inFIG. 5, and the laser beams oscillate in the left-right direction, the present invention is not limited to this. Moreover, in the first embodiment, as illustrated inFIG. 6, although the laser sensor24B irradiates laser beams in an irradiation area IAV about a direction inclined closer to a lower side than a horizontal direction from the vehicle body21in a side view of the vehicle body21, the present invention is not limited to this.

Moreover, the radar24A and the laser sensor24B are connected to a second communication line37of the construction machine control system30. Moreover, the laser sensor24B is connected to a position measurement controller33of the construction machine control system30.

Next, the construction machine control system will be described.FIG. 7is a diagram for describing a method by which the travel controller of the construction machine control system according to the first embodiment specifies a position and a direction.FIG. 8is a diagram for describing a method by which a matching navigation calculation unit of the position measurement controller of the construction machine control system according to the first embodiment specifies a position and a direction.FIG. 9is a diagram illustrating a portion of map information stored in a map storage database of the construction machine control system according to the first embodiment.FIG. 10is an enlarged view of a portion indicated by XIV inFIG. 9.

The construction machine control system30is a system that is provided in the dump truck2so as to allow the dump truck2to autonomously travel along the travel route RP. As illustrated inFIG. 3, the construction machine control system30includes a gyro sensor26, a speed sensor27, a GPS receiver31, a travel route creating device32, a position measurement controller33, a travel controller20, the laser sensor24B, a wireless communication device34, and a map storage database36. In addition to these components, the construction machine control system30further includes a first communication line35, the second communication line37, and a safety controller40.

As illustrated inFIG. 3, the travel controller20, the travel route creating device32, the position measurement controller33, the map storage database36, and the safety controller40are connected to the first communication line35. These components communicate with each other via the first communication line35to transmit and receive information. The travel controller20and the safety controller40are also connected to the second communication line37. These components communicate with each other via the second communication line37to transmit and receive information. In the first embodiment, although the standard of the communication using the first and second communication lines35and37is CAN (controller area network) which is standardized as ISO 11898 and ISO 11519.

The gyro sensor26detects the direction (an amount of directional change) of the dump truck2. The gyro sensor26is connected to the travel controller20. The gyro sensor26outputs a detection signal which is a detection result to the travel controller20. The travel controller20can calculate the direction (the amount of directional change) of the dump truck2based on the detection signal of the gyro sensor26.

The speed sensor27detects a travel speed of the dump truck2. In the first embodiment, the speed sensor27detects a rotation speed of the wheel23to detect the speed (travel speed) of the dump truck2. The speed sensor27is connected to the travel controller20. The speed sensor27outputs a detection signal which is a detection result to the travel controller20. The travel controller can calculate the moving distance of the dump truck2based on the detection signal of the speed sensor27and time information calculated from a timer included in the travel controller20.

The GPS receiver31is a position detection unit that detects the GPS position which is the position of the dump truck2using a GPS. The GPS receiver31is connected to at least one of an antenna31A that receives information from the positioning satellite5and an antenna31B that receives correction measurement information from the GPS base station19. The antenna31A outputs a signal based on the information received from the positioning satellite5to the GPS receiver31, and the antenna31B outputs a signal based on the received correction measurement information to the GPS receiver31. The GPS receiver31detects the position (the GPS position) of the antenna31A using the information from the positioning satellite5and the correction measurement information from the GPS base station19. Specifically, the GPS receiver31compares the information from the positioning satellite5and the correction measurement information from the GPS base station19to calculate the distance to an arbitrary positioning satellite5, and examines the phase of the radio waves from the positioning satellite5to detect the position (the GPS position) of the antenna31A. In the first embodiment, although the GPS receiver31uses an RTK (real time kinematic)-GNSS, the present invention is not limited to this.

The GPS receiver31detects the position (the GPS position) of the dump truck2by detecting the position (the GPS position) of the antenna31A. Moreover, the GPS receiver31detects a Fix solution, a Float solution, or a Single solution indicating the accuracy of the detected GPS position based on the number of the positioning satellites from which the antenna31A has received information, for example, in the process of detecting the position of the antenna31A. The GPS receiver31outputs a signal indicating No solution when the GPS position cannot be measured. In the first embodiment, when the accuracy of the GPS position is Fix solution, the dump truck2can perform autonomous travel whereas when the accuracy of the GPS position is Float or Single solution, the dump truck2cannot perform autonomous travel. However, the present invention is not limited to this. In this manner, the GPS receiver31detects the Fix, Float, or Single solution indicating the accuracy of the detected GPS position and outputs a signal indicating No solution when the GPS position cannot be measured to the travel controller20and the position measurement controller33via the travel route creating device32.

As illustrated inFIG. 2, the travel route creating device32includes a route position storage unit32A which is a route position storage unit that stores information on the travel route RP generated by the processing device12of the management device10. The travel route creating device32is connected to the wireless communication device34to which an antenna34A is connected. The wireless communication device34can receive information (including an instruction signal) transmitted from at least one of the management device10and the construction machine4other than a subject vehicle. The construction machine4other than the subject vehicle is a construction machine4other than the dump truck2in which the construction machine control system30is provided and includes a boring machine, an excavating machine, a loading machine, a transport machine, and a vehicle that is driven by an operator. That is, the construction machine4other than the subject vehicle includes the dump truck2other than the subject vehicle.

The wireless communication device34receives information on the travel route RP and information on the position of the construction machine4other than the subject vehicle transmitted by the wireless communication device18of the control facility7and outputs the information to the travel route creating device32and the position measurement controller33. The information on the travel route RP and the information on the position of the construction machine4other than the subject vehicle are represented by X-Y coordinates. Upon receiving the information on the travel route RP and the information on the position of the construction machine4other than the subject vehicle from the wireless communication device34, the travel route creating device32stores the information in the route position storage unit32A. Upon receiving the information on the travel route RP and the information on the position of the construction machine4other than the subject vehicle from the wireless communication device34, the travel route creating device32transmits the position and direction of the dump truck2which is the subject vehicle to the wireless communication device18of the control facility7via the wireless communication device34. Moreover, the travel route creating device32is connected to the first communication line35.

The travel controller20is a computer that includes at least a central processing unit (CPU), read only memory (ROM) that stores a control program, random access memory (RAM) used as a work area of the CPU, and nonvolatile memory. The travel controller20receives the GPS position detected by the GPS receiver31and the position of the dump truck2detected by the position measurement controller33. The travel controller20is a control unit that allows the dump truck2to autonomously travel along the travel route RP based on the GPS position of the dump truck2, detected by the GPS receiver31or the position of the dump truck2, detected by a matching navigation calculation unit33B of the position measurement controller33.

The detection signal indicating the direction (the amount of directional change) of the dump truck2, which is the detection result of the gyro sensor26other than the position of the dump truck2and the detection signal indicating the travel speed of the dump truck2, which is the detection result of the speed sensor27are input to the travel controller20. In the first embodiment, the detection signal indicating the direction (the amount of directional change) of the dump truck2and the detection signal indicating the travel speed of the dump truck2, which is the detection result of the speed sensor27are input to the travel controller20every T1. Moreover, the travel controller20is connected to the GPS receiver31via the wireless communication device34, the travel route creating device32, and the first communication line35. The detection signal indicating the GPS position which is the detection result of the GPS receiver31is input to the travel controller20. In the first embodiment, the detection signal indicating the GPS position is input to the travel controller20every T2that is longer than T1.

The travel controller20specifies the position and direction of the dump truck2based on the GPS position which is the detection result of the GPS receiver31, the travel speed of the dump truck2, which is the detection result of the speed sensor27, and the direction (the amount of directional change) of the dump truck2, which is the detection result of the gyro sensor26. In the first embodiment, as illustrated inFIG. 7, the travel controller combines the GPS position which is the detection result of the GPS receiver31, the travel speed of the dump truck2, which is the detection result of the speed sensor27, and the direction (the amount of directional change) of the dump truck2, which is the detection result of the gyro sensor26using a Kalman filter KF to specify the position and direction of the dump truck2. Specifically, the travel controller20integrates the travel speed which is the detection result of the speed sensor27by the time information from the timer based on the GPS position at the time at which the GPS position is input from the GPS receiver31and the direction which is the detection result of the gyro sensor26to specify the position and direction. The travel controller20converts the GPS position before, during, or after detection of the position and direction to the position in the X-Y coordinate.

The travel controller20controls at least one of the accelerator of the dump truck2, a braking device (not illustrated), and a steering device2S so that the position of the dump truck2overlaps the position of the travel route RP included in the travel route information (that is, the dump truck2travels along the travel route RP). According to such control, the travel controller20allows the dump truck2to travel along the travel route RP. The function of the travel controller20is realized when the CPU reads the control program stored in the ROM and executes the control program in a work area of the RAM. Moreover, a plurality of processing circuits may realize the function of the travel controller20in collaboration.

As illustrated inFIG. 2, the position measurement controller33includes a determining unit33A, a matching navigation calculation unit33B, and a grid map creating unit33C. The position measurement controller33is configured to detect the GPS position of the dump truck2, which is the detection result of the GPS receiver31and the position of the vertical projection VP (in the first embodiment, mainly the bank BK) from the detection result of the laser sensor24B when the dump truck2travels along the travel route RP and stores the detected position of the vertical projection VP in the map storage database36as map information MI of the travel route RP. The position measurement controller33is connected to the first communication line35. The detection signal indicating the direction (the amount of directional change) of the dump truck2, which is the detection result of the gyro sensor26and the detection signal indicating the travel speed of the dump truck2, which is the detection result of the speed sensor27are input to the position measurement controller33via the first communication line35and the travel controller20.

Moreover, the position measurement controller33is connected to the GPS receiver31via the wireless communication device34, the travel route creating device32, and the first communication line35. The detection signal indicating the GPS position which is the detection result of the GPS receiver31is input to the position measurement controller33.

The determining unit33A is a determination unit that determines whether an error in the GPS position detected by the GPS receiver31is equal to or smaller than a predetermined error. In the first embodiment, the determining unit33A determines whether the solution of the GPS position is a Fix solution, and if the solution of the GPS position is the Fix solution, determines that the accuracy of the detected GPS position of the dump truck2is high and the error in the GPS position is equal to or smaller than a predetermined error. When the solution of the GPS position is a Float solution or a Single solution, or the GPS position is No solution, the determining unit33A determines that the accuracy of the detected GPS position of the dump truck2is low and the error in the GPS position exceeds the predetermined error. The predetermined error is an error (accuracy) of the GPS position, in which the dump truck2can autonomously travel along the travel route RP according to dead reckoning described later. In the first embodiment, although the GPS receiver31detects the GPS position and the solution, the solution may be detected by another device (for example, the determining unit33A).

When the determining unit33A determines that the error in the GPS position of the dump truck2, detected by the GPS receiver31is equal to or smaller than the predetermined error, the grid map creating unit33C detects the position of the vertical projection VP (in the first embodiment, mainly the bank BK) provided in at least one of the loading area LPA, the dumping area DPA, and the haul road HL based on the detection result of the gyro sensor26, the detection result of the speed sensor27, and the detection result of the laser sensor24B and stores information on the position of the vertical projection VP in the map storage database36as the map information MI of the travel route RP. Specifically, the grid map creating unit33C combines the position and direction of the dump truck2, detected by the travel controller20and the detection result of the laser sensor24B and removes the detection result other than the vertical projection VP from the combined information to detect the position of the vertical projection VP. Moreover, the map information MI that the grid map creating unit33C stores in the map storage database36indicates the X-Y coordinate positions of grids GR obtained by breaking a mine into quadrangles (rectangles or squares) of a predetermined size and whether the vertical projection VP is present in each grid GR in a plan view as illustrated inFIGS. 9 and 10. Each grid GR in the map information MI includes information on whether the vertical projection VP is present or not (that is, 0 or 1). In the first embodiment, as illustrated inFIGS. 9 and 10, although each grid GR in the map information MI is depicted as a black quadrangle in the figure to indicate “1” if the vertical projection VP is present or as a white quadrangle in the figure to indicate “0” if the vertical projection VP is not present, the present invention is not limited to this.

The map storage database36is a map information storage unit that stores information on the position of the vertical projection VP as the map information MI of the travel route RP and is connected to a first travel control CAN35. The map storage database36is configured by at least one of random access memory (RAM), read only memory (ROM), flash memory, and a hard disk drive. When the determining unit33A determines that the error in the GPS position of the dump truck2, detected by the GPS receiver31is equal to or smaller than the predetermined error, the map storage database36extracts the detection result related to the vertical projection VP that protrudes vertically from the surface of the travel route RP from the detection result of the laser sensor24B and stores the extracted detection result related to the vertical projection VP as the map information MI of the travel route RP. The map storage database36stores the detection result detected by the grid map creating unit33C as the map information MI whenever the grid map creating unit33C detects the detection result. In the first embodiment, although the map information MI stored in the map storage database36is overwritten whenever the grid map creating unit33C detects the detection result, the present invention is not limited to this.

When the determining unit33A determines that the error in the GPS position of the dump truck2, detected by the GPS receiver31exceeds the predetermined error, the matching navigation calculation unit33B specifies the position and direction of the dump truck2based on the detection result of the laser sensor24B and the map information MI stored in the map storage database36. As illustrated inFIG. 8, the matching navigation calculation unit33B combines the detection result of the gyro sensor26, the detection result of the speed sensor27, the detection result of the laser sensor24B, and the map information MI stored in the map storage database36using a particle filter PF to specify the position and direction of the dump truck2. In the first embodiment, the matching navigation calculation unit33B specifies the position and direction every T3that is longer than T1and shorter than T2and outputs the specified position and direction to the travel controller20. In the first embodiment, the position and direction detected by the matching navigation calculation unit33B is input to the travel controller20every T3. As described above, the position measurement controller33is a position measurement unit that specifies the position of the dump truck2by comparing the detection result of the laser sensor24B and the map information MI stored in the map storage database36when the determining unit33A determines that the error in the GPS position of the dump truck2detected by the GPS receiver31exceeds the predetermined error.

Moreover, the position measurement controller33transmits information on the position and direction of the dump truck2which is the subject vehicle, detected by the GPS receiver31or the matching navigation calculation unit33B to the wireless communication device18of the control facility7via the wireless communication device34.

Further, as illustrated inFIG. 2, the position measurement controller33includes a measurement point coordinate conversion unit38and a measurement point availability determining unit39. The measurement point coordinate conversion unit38converts the position of the detection result of the laser sensor24B expressed using a coordinate that is defined by the direction and the distance from the laser sensor24B to the X-Y coordinate. The position of the detection result which is coordinate-converted by the measurement point coordinate conversion unit38is defined by an X-axis direction, a Y-axis direction, and a height direction (a Z-axis direction) orthogonal to these directions. The information on the position of the construction machine4other than the subject vehicle is input from the route position storage unit32A to the measurement point availability determining unit39. The measurement point availability determining unit39removes various noise components, a detection result in which the height from the ground surface is equal to or lower than a predetermined height, and a detection result in which it is expected that the construction machine4other than the subject vehicle has been detected from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38. The measurement point availability determining unit39combines the detection result of the laser sensor24B, from which noise components are removed with the detection result of the grids GR. The measurement point availability determining unit39outputs the combined detection result to both the grid map creating unit33C and the matching navigation calculation unit33B.

The position measurement controller33includes at least a communication input and output unit, a central processing unit (CPU) that executes a control program, read only memory (ROM) that stores the control program, random access memory (RAM) that is used as a work area of the CPU, and nonvolatile memory in which information is registered by the CPU.

The position measurement controller33is realized by a CPU, RAM, and ROM. The functions of the determining unit33A, the matching navigation calculation unit33B, the grid map creating unit33C, the measurement point coordinate conversion unit38, and the measurement point availability determining unit39are realized when the CPU reads the control program stored in the ROM and executes the control program in the work area of the RAM. The nonvolatile memory includes at least one of flash memory and a hard disk drive. Moreover, a plurality of processing circuits may realize the functions of the determining unit33A, the matching navigation calculation unit33B, the grid map creating unit33C, the measurement point coordinate conversion unit38, and the measurement point availability determining unit39in collaboration.

The safety controller40calculates a relative position between the dump truck2and an obstacle based on the detection signals of the radar24A and the laser sensor24B. The safety controller40generates an instruction for controlling at least one of an accelerator, a braking device (not illustrated), and the steering device2S using the relative position to the obstacle and outputs the instruction to the travel controller20. The travel controller20controls the dump truck2based on the instruction acquired from the safety controller40to avoid the dump truck2from colliding with the obstacle.

Moreover, the travel controller20outputs an instruction for controlling the braking device (not illustrated) that brakes the vehicle body21when the solution of the GPS position is the Float or Single solution or when a state in which the GPS position is not measured has continued a predetermined period and the matching navigation calculation unit33B can only obtain the detection result of the laser sensor24B in which the estimation accuracy and the reliability level of the map information MI stored in the map storage database36are lower than a predetermined value and a predetermined reliability level.

Next, a construction machine control method according to the first embodiment (that is, an example of the operation of the construction machine control system30) will be described.FIG. 11is an example of the flowchart of the construction machine control system according to the first embodiment.FIG. 12is an example of the flowchart of step ST4inFIG. 11.FIG. 13is an example of the flowchart of step ST42inFIG. 12.FIG. 14is an example of the flowchart of step ST6inFIG. 11.FIG. 15is an example of the flowchart of step ST64inFIG. 14.FIG. 16is a diagram illustrating an example of an expected detection result of positions and directions detected by the matching navigation calculation unit of the construction machine control system according to the first embodiment.FIG. 17is a diagram illustrating an example of a detection result actually detected by the laser sensor of the construction machine control system according to the first embodiment.FIG. 18is a diagram illustrating an example of a state in which the matching navigation calculation unit of the position measurement controller of the construction machine control system according to the first embodiment calculates the closest detection result.

The construction machine control method is a method by which the construction machine control system30allows the dump truck2to autonomously travel along the travel route RP. In the construction machine control method, the processing device12transmits an instruction signal to the travel route creating device32and the position measurement controller33of the dump truck2via the wireless communication device18. The instruction signal includes information on the travel condition of the dump truck2and information on the position of the construction machine4other than the subject vehicle. The information on the travel condition includes the information on the travel route RP generated by the processing device12and the information on the travel speed of the dump truck2.

The travel route creating device32stores the information on the travel route RP and the information on the position of the construction machine4other than the subject vehicle among the instruction signals transmitted from the processing device12via the communication system9in the route position storage unit32A. When the travel route creating device32receives the instruction signal from the processing device12, including the information on the travel route RP, the position measurement controller33transmits information on the position and direction of the dump truck2which is the subject vehicle to the processing device12via the wireless communication device34. The travel controller20controls the accelerator of the dump truck2, the braking device (not illustrated), and the steering device2S based on the instruction signal from the processing device12to control the travel of the dump truck2.

The travel controller20of the construction machine control system30executes step ST1of allowing the dump truck2to travel according to dead reckoning along the travel route RP based on the GPS position of the dump truck2, detected by the GPS receiver31. In the first embodiment, the travel controller20allows the dump truck2to travel in at least a portion of the loading area LPA, the dumping area DPA, the haul road HL, and the intersection IS according to the travel condition including the information on the travel route RP generated by the processing device12of the management device10and the travel speed (a target travel speed) set by the processing device12. The dead reckoning means a navigation method of predicting the present position of an object (the dump truck2) based on the direction (the amount of directional change) and the moving distance from a known position. The direction (the amount of directional change) of the dump truck2is detected using the gyro sensor26disposed in the dump truck2. The moving distance of the dump truck2is detected using the speed sensor27disposed in the dump truck2. The detection signal of the gyro sensor26and the detection signal of the speed sensor27are output to the travel controller20of the dump truck2.

The travel controller20can calculate the direction (the amount of directional change) of the dump truck2from a known start point based on the detection signal from the gyro sensor26. The travel controller20can calculate the moving distance of the dump truck2from the known start point based on the detection signal from the speed sensor27. The travel controller20generates a control amount related to the travel of the dump truck2based on the detection signal from the gyro sensor26and the detection signal from the speed sensor27so that the dump truck2travels along the generated travel route RP. The control amount includes an accelerator signal, a braking signal, and a steering signal. The travel controller20controls the travel (operation) of the dump truck2based on the steering signal, the accelerator signal, and the braking signal.

Next, an example in which the dump truck2travels while the prediction position calculated by dead reckoning is corrected using the RTK-GNSS or the matching navigation calculation unit33B. When the travel distance of the dump truck2increases, a difference may occur between the predicted position (prediction position) and the actual position due to an accumulated detection error in one or both of the gyro sensor26and the speed sensor27. As a result, the dump truck2may travel off the travel route RP generated by the processing device12. In the first embodiment, the travel controller20allows the dump truck2to travel while correcting the position (the prediction position) of the dump truck2derived (predicted) according to dead reckoning using the GPS position detected by the GPS receiver31or the position detected by the matching navigation calculation unit33B. The travel controller20calculates a control amount related to the travel of the dump truck2, including a correction amount for correcting the position of the dump truck2based on the detection signal from the gyro sensor26, the detection signal from the speed sensor27, the GPS position from the GPS receiver31, or the position detected by the matching navigation calculation unit33B so that the dump truck2travels along the travel route RP. The travel controller20controls the travel (operation) of the dump truck2based on the calculated correction amount and control amount so that the dump truck2travels along the travel route RP.

Subsequently, the determining unit33A of the position measurement controller33executes step ST2of determining whether an error in the GPS position of the dump truck2, detected by the GPS receiver31is equal to or smaller than a predetermined error. That is, in step ST2, the determining unit33A of the position measurement controller33determines whether the accuracy of the GPS position of the dump truck2, detected by the GPS receiver31is high. Specifically, the determining unit33A of the position measurement controller33determines whether the solution of the GPS position detected by the GPS receiver31is the Fix solution. When it is determined that the solution of the GPS position detected by the GPS receiver31is the Fix solution (that is, the error in the GPS position of the dump truck2, detected by the GPS receiver31is equal to or smaller than the predetermined error) (step ST2: Yes), the determining unit33A of the position measurement controller33determines whether the travel speed of the dump truck2is 0 based on the detection signal of the speed sensor27(that is, whether the dump truck2is in a stopped state) (step ST3).

When the determining unit33A of the position measurement controller33determines that the travel speed of the dump truck2is not 0 (that is, the dump truck2is not in the stopped state) (step ST3: Yes), the grid map creating unit33C creates the map information MI (step ST4). That is, when it is determined that the error in the GPS position detected by the GPS receiver31is equal to or smaller than the predetermined error, the position measurement controller33executes step ST4of extracting a detection result related to the vertical projection VP from the detection result of the laser sensor24B and storing the detection result related to the vertical projection VP in the map storage database36as the map information MI of the travel route RP. Specifically, first, the measurement point coordinate conversion unit38converts the position of the detection result of the laser sensor24B expressed using a coordinate that is defined by the direction and the distance from the laser sensor24B to a coordinate position expressed by the X-Y coordinate (step ST41).

The measurement point availability determining unit39extracts a detection result related to the vertical projection VP from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38(step ST42). When the detection result related to the vertical projection VP is extracted, first, the measurement point availability determining unit39removes various noise components from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38(step ST421). Specifically, the measurement point availability determining unit39removes a detection result in which reflection intensity is low, a detection result in which it is considered that a laser beam has passed through a transparent object, a detection result in which it is considered that a laser beam has detected dust, a detection result in which it is considered that a laser beam has been reflected, and a detection result in which it is considered that a laser beam has detected a lump of earth on the ground surface from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38as noise components.

The measurement point availability determining unit39removes a detection result in which the distance is equal to or larger than a predetermined largest distance and a detection result in which the distance is equal to or smaller than a predetermined smallest distance from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38(step ST422). In the first embodiment, the predetermined largest distance is the distance necessary for removing noise components resulting from the sunlight and the predetermined smallest distance is the distance for removing noise components of dense dust generated at a short distance from the laser sensor24B.

The measurement point availability determining unit39removes a detection result in which the height from the ground surface is equal to or smaller than a predetermined height from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38(step ST423). In the first embodiment, although the measurement point availability determining unit39removes the detection result in which the height is equal to or smaller than the predetermined height, the present invention is not limited to this. The measurement point availability determining unit39removes a detection result in which it is expected that the construction machine4other than the subject vehicle has been detected from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38by referring to the information on the position of the construction machine4other than the subject vehicle stored in the route position storage unit32A (step ST424). In this manner, the measurement point availability determining unit39extracts the detection result related to the vertical projection VP from the detection result by removing various noise components or the like from the detection result. By the process of step ST424, the detection result of the laser sensor24B can be reduced by approximately ⅕ to ⅙ as compared to before processing.

The measurement point availability determining unit39combines the detection result in which various noise components or the like are removed with a detection result in which the position is expressed by the X-Y coordinate and which is formed of grids GR of a predetermined size. The measurement point availability determining unit39outputs the combined detection result to both the grid map creating unit33C and the matching navigation calculation unit33B. The grid map creating unit33C of the position measurement controller33stores the position of the vertical projection VP, which is the detection result combined by the measurement point availability determining unit39in the map storage database36as the map information MI of the travel route RP (step ST43). As described above, the ROM of the position measurement controller33stores a program for causing the position measurement controller33which is a computer to execute steps ST2and ST4. Moreover, the construction machine control method executes steps ST1to ST4to thereby extract the detection result related to the vertical projection VP from the detection result of the laser sensor24B and store the extracted detection result related to the vertical projection VP as the map information MI of the travel route RP when the error in the GPS position of the dump truck2detected by the GPS receiver31is equal to or smaller than the predetermined error.

When the determining unit33A of the position measurement controller33determines that the travel speed of the dump truck2is 0 (that is, the dump truck2is in a stopped state) (step ST3: No), the flow returns to step ST1. The determining unit33A returns to step ST1when the travel speed of the dump truck2is 0 (step ST3: No) whereby the map storage database36stops storing the map information MI of the travel route RP when the speed sensor27detects a stopped state of the dump truck2. This is because, when the dump truck2of which the travel speed is 0 is in a stopped state, noise components may be mixed into the map information MI due to dust or the like generated during operation of the construction machine4other than the subject vehicle and the accuracy of the map information MI may decrease.

Moreover, when it is determined that the solution of the GPS position detected by the GPS receiver31is not the Fix solution (that is, it is determined that the error in the GPS position of the dump truck2detected by the GPS receiver31exceeds the predetermined error) (step ST2: No), the determining unit33A of the position measurement controller33determines whether the travel speed of the dump truck2is 0 based on the detection signal of the speed sensor27(that is, whether the dump truck2is in a stopped state) (step ST5).

When the determining unit33A of the position measurement controller33determines that the travel speed of the dump truck2is not 0 (that is, the dump truck2is not in the stopped state) (step ST5: Yes), the matching navigation calculation unit33B specifies the position and direction of the dump truck2based on the detection result of the laser sensor24B and the map information MI stored in the map storage database36, and the travel controller allows the dump truck2to travel along the travel route RP (step ST6). That is, when the determining unit33A determines that the error in the GPS position detected by the GPS receiver31exceeds the predetermined error, the position measurement controller33specifies the position and direction of the dump truck2by comparing the detection result of the laser sensor24B and the map information MI stored in the map storage database36. Moreover, the travel controller20allows the dump truck2to travel along the travel route RP based on the position detected by the matching navigation calculation unit33B of the position measurement controller33.

Specifically, the measurement point coordinate conversion unit38converts the position of the detection result of the laser sensor24B expressed by a coordinate that is defined by the direction and the distance from the laser sensor24B to the X-Y coordinate position (step ST61). The measurement point availability determining unit39extracts a detection result related to the vertical projection VP from the detection result which is coordinate-converted by the measurement point coordinate conversion unit38(step ST62). Since step ST61is the same process as step ST41and step ST62is the same process as step ST42, the detailed description thereof will be omitted.

The matching navigation calculation unit33B thins out the detection result by passing the detection result in which the noise components are removed by the measurement point availability determining unit39through an isolation filter (step ST63). Specifically, the matching navigation calculation unit33B leaves only detection results which are separated by a predetermined distance or more among the detection results in which the noise components are removed by the measurement point availability determining unit39and removes the other detection results. By the process of step ST63, the detection result of the laser sensor24B can be reduced by approximately ⅕ to ⅙ as compared to before processing.

The matching navigation calculation unit33B combines the detection result of the gyro sensor26, the detection result of the speed sensor27, the detection result of the laser sensor24B, and the map information MI stored in the map storage database36using a particle filter PF to specify the position and direction of the dump truck2(step ST64). Specifically, the matching navigation calculation unit33B calculates a plurality of positions and directions within a range in which it is expected that the dump truck2is present at a certain time point based on the direction which is the detection result of the gyro sensor26and the travel speed which is the detection result of the speed sensor27(step ST641).

As illustrated inFIG. 16, the matching navigation calculation unit33B estimates a detection result that the laser sensor24B is expected to detect when the dump truck2is positioned at each of expected positions and directions based on the map information MI stored in the map storage database36. The matching navigation calculation unit33B compares a detection result DR1that the laser sensor24B is expected to detect at each position and direction, illustrated as an example inFIG. 16and a detection result DR2that the laser sensor24B has actually detected, illustrated inFIG. 17to calculate the likelihood of the detection result DR1that the laser sensor24B is expected to detect at each position and direction to the detection result DR2that the laser sensor24B has actually detected. The matching navigation calculation unit33B normalizes the likelihood at each position and direction (step ST642).

The matching navigation calculation unit33B calculates a final estimation value from the respective positions and the likelihood of the detection result DR1that the laser sensor24B is expected to detect at each position and direction and calculates a position and a direction at which the detection result DR1that the laser sensor24B is expected to detect is most similar to the detection result DR2that the laser sensor24B has actually detected as illustrated inFIG. 18. The matching navigation calculation unit33B detects the most similar position and direction as the position and direction of the dump truck2. When the most similar position and direction are calculated, the matching navigation calculation unit33B calculates the estimation accuracy and the reliability of the most similar position and direction (step ST643).FIGS. 16 and 18illustrate the grids GR in which the vertical projection VP is present by dense oblique hatched lines andFIG. 17illustrates the detection result of the vertical projection VP by coarse oblique hatched lines. AlthoughFIG. 18illustrates an example which the detection result DR2that the laser sensor24B has actually detected is a portion of the detection result DR1, the present invention is not limited to this.

The matching navigation calculation unit33B performs various diagnoses at the detected position and direction of the dump truck2(step ST644). Specifically, when the detected position and direction of the dump truck2are detected from the detection result detected during a failure in the laser sensor24B, from the detection result detected during a failure in the gyro sensor26, or from a number of detection results of the laser sensor24B smaller than a predetermined number, the reliability is lower than a predetermined reliability, the likelihood is lower than a predetermined value, the estimation accuracy is lower than a predetermined value, a shift from the position and direction obtained by dead reckoning is larger than a predetermined value, or the detected position and direction are detected using wrong map information MI, the matching navigation calculation unit33B discards the detected position and direction of the dump truck2and calculates a plurality of positions and directions within a range in which it is expected that the dump truck2is present at a certain time point again (step ST645). The plurality of calculated positions and directions are used as a plurality of positions and directions calculated in step ST641when step ST6is executed later.

Moreover, the detected position and direction of the dump truck2are not detected from the detection result detected during a failure in the laser sensor24B, from the detection result detected during a failure in the gyro sensor26, or from a number of detection results of the laser sensor24B smaller than a predetermined number, the reliability is not lower than a predetermined reliability, the likelihood is not lower than a predetermined value, the estimation accuracy is not lower than a predetermined value, a shift from the position and direction obtained by dead reckoning is not larger than a predetermined value, and the detected position and direction are not detected using wrong map information MI, the matching navigation calculation unit33B executes the dead reckoning (step ST1) using the detected position and direction and the position measurement controller33controls the travel (operation) of the dump truck2so that the dump truck2travels along the travel route RP.

When the determining unit33A of the position measurement controller33determines that the travel speed of the dump truck2is 0 (that is, the dump truck2is in a stopped state) (step ST5: No), the flow returns to step ST1. The determining unit33A returns to step ST1when the travel speed of the dump truck2is 0 (step ST5: No) whereby the position measurement controller33stops specifying the position and direction of the dump truck2by comparing the detection result of the laser sensor24B and the map information MI of the travel route RP stored in the map storage database36when the speed sensor27detects a stopped state of the dump truck2. This is because, when the dump truck2of which the travel speed is 0 is in a stopped state, noise components may be mixed into the detection result of the laser sensor24B due to dust or the like generated during operation of the construction machine4other than the subject vehicle and the position measurement accuracy of the matching navigation calculation unit33B may decrease. Moreover, this is because the position of the dump truck2does not change when the dump truck2of which the travel speed is 0 is in a stopped state.

In the first embodiment, when the solution of the GPS position detected by the GPS receiver31is the Fix solution, the construction machine control system30, the construction machine control method, and the program stored in the position measurement controller33create the map information MI composed of the position of the vertical projection VP based on the detection result of the laser sensor24B and stores the map information MI in the map storage database36while allowing the dump truck2to autonomously travel along the travel route RP based on the GPS position and the like. As a result, the accuracy of the map information MI is improved. Thus, even when it is not possible to specify the position and direction using a GPS, the construction machine control system30can allow the dump truck2to travel along the travel route RP by specifying the position and direction of the subject vehicle based on the map information MI having improved accuracy and the detection result of the laser sensor24B. Moreover, the construction machine control system30can allow the dump truck2to travel continuously (that is, the operations of the mine can be performed continuously).

Moreover, since the construction machine control system30stops storing the map information MI in a period in which the dump truck2is in a stopped state, it is possible to suppress the noise components from being included in the map information MI stored in the map storage database36. As a result, even when it is not possible to specify the position and direction using a GPS, since the construction machine control system30can specify the position and direction of the subject vehicle based on the map information MI with small noise, the dump truck2can continue travel (that is, the operations in a mine can be continuously performed).

When the solution of the GPS position detected by the GPS receiver31is not the Fix solution, the construction machine control system30according to the first embodiment compares the detection result of the laser sensor24B and the map information MI stored in the map storage database36to specify the position and direction of the dump truck2. As a result, even when it is not possible to specify the position and direction using a GPS, the construction machine control system30can specify the position and direction based on the detection result of the laser sensor24B which provides higher resolution than the radar24A and the map information MI. Thus, the dump truck2can travel continuously (that is, the operations of the mine can be performed continuously).

The construction machine control system30stops specifying the position and direction of the dump truck2by comparing the detection result of the laser sensor24B and the map information MI stored in the map storage database36in a period in which the dump truck2is in a stopped state. As a result, the construction machine control system30can suppress the position and direction of the dump truck4from being updated unnecessarily during stopping.

In the first embodiment, since the dump truck2and the management system1include the construction machine control system30, the map information MI composed of the position of the vertical projection VP is stored in the map storage database36when the solution of the GPS position detected by the GPS receiver31is the Fix solution. Thus, since it is possible to specify the position and direction of the subject vehicle using the map information MI even when it is not possible to specify the position and direction using a GPS, the dump truck2can travel continuously (that is, the operations of the mine can be performed continuously).

Moreover, the construction machine control system can decrease the amount of information of the entire map information MI since the grids GR of the map information MI are composed of information indicating whether the vertical projection VP is present or not (that is, 0 or 1). As a result, the construction machine control system30can specify the position of the dump truck2in realtime even when the position measurement controller33provided in the dump truck2has a limited processing capability. Moreover, even when it is not possible to specify the position and direction using a GPS, the construction machine control system30can allow the dump truck2to travel continuously (that is, the operations of the mine can be performed continuously).

The measurement point availability determining unit39of the construction machine control system30removes a detection result in which reflection intensity is low, a detection result in which it is considered that a laser beam has passed through a transparent object, a detection result in which it is considered that a laser beam has detected dust, a detection result in which it is considered that a laser beam has been reflected, and a detection result in which it is considered that a laser beam has detected a lump of earth on the ground surface from the detection result of the laser sensor24B as noise components. The measurement point availability determining unit39of the construction machine control system30removes a detection result in which the distance is equal to or larger than a largest distance, a detection result in which the distance is equal to or smaller than a smallest distance, a detection result in which the height is equal to or smaller than a predetermined height, and a detection result in which it is expected that the construction machine4other than the subject vehicle is detected from the detection result of the laser sensor24B. As a result, the construction machine control system30can decrease the amount of information other than the vertical projection VP in the map information MI stored in the map storage database36and reduce the amount of information stored in the map storage database36provided in the dump truck2. Moreover, since the matching navigation calculation unit33B can specify the position and direction of the subject vehicle based on the map information MI with little noise, it is possible to accurately specify the position of the dump truck2.

The matching navigation calculation unit33B of the construction machine control system30further reduces the detection result by passing the detection result of the laser sensor24B in which various noise components are removed through an isolation filter. As a result, the construction machine control system30can specify the position of the dump truck2in realtime even when the position measurement controller33provided in the dump truck2has a limited processing capability. Moreover, even when it is not possible to specify the position and direction using a GPS, the construction machine control system30can allow the dump truck2to travel continuously (that is, the operations of the mine can be performed continuously).

The matching navigation calculation unit33B of the construction machine control system30performs various diagnoses at the position and direction of the dump truck2detected by the particle filter PF, it is possible to suppress a detection error in the position and direction of the dump truck2. As a result, even when it is not possible to specify the position and direction using a GPS, the construction machine control system30can allow the dump truck2to travel continuously (that is, the operations of the mine can be performed continuously).

When the solution of the GPS position detected by the GPS receiver31is the Fix solution, the construction machine control system30creates the map information MI based on the detection result of the laser sensor24B and stores the map information MI. When the solution of the GPS position detected by the GPS receiver31is not the Fix solution, the construction machine control system30compares the detection result of the laser sensor24B and the map information MI stored in the map storage database36to specify the position and direction of the dump truck2. As described above, in the construction machine control system30, each dump truck2creates the map information MI, and when the error in the GPS position exceeds a predetermined error, each dump truck2travels using the map information MI created by itself. As a result, even when the grids GR of the map information MI are composed of information indicating whether the vertical projection VP is present (that is, 0 or 1) and a difference occurs in the detection results of the laser sensors24B between the dump trucks2due to an individual difference of the dump trucks2, the construction machine control system30can detect the position of the subject vehicle with high accuracy using the map information MI created by itself. Thus, even when it is not possible to specify the position and direction using a GPS, the construction machine control system30can allow the dump truck2to travel continuously (that is, the operations of the mine can be performed continuously).

Second Embodiment

Next, a construction machine control method according to a second embodiment (that is, an example of the operation of the construction machine control system30) will be described.FIG. 19is an example of the flowchart of a construction machine control system according to the second embodiment.FIG. 20is an example of the flowchart of step ST7inFIG. 19. InFIGS. 19 and 20, the same portions as those of the first embodiment will be denoted by the same reference numerals, and the description thereof will be omitted. The construction machine control system of the second embodiment has the same configuration as the construction machine control system30of the first embodiment.

According to the construction machine control method of the second embodiment, when the determining unit33A of the position measurement controller33determines that the travel speed of the dump truck2is not 0 (that is, the dump truck2is not in the stopped state) (step ST3: Yes), the grid map creating unit33C creates the map information MI (step ST4), and the matching navigation calculation unit33B specifies the position and direction of the dump truck2based on the detection result of the laser sensor24B and the map information MI stored in the map storage database36and checks the accuracy of the detected position and direction (step ST7).

Specifically, similarly to the first embodiment, the measurement point coordinate conversion unit38converts the position of the detection result of the laser sensor24B to the X-Y coordinate position. The measurement point availability determining unit39extracts the detection result related to the vertical projection VP from the detection result which has been coordinate-converted and combines the detection result into a detection result of which the position is expressed by the X-Y coordinate and which is composed of a plurality of grids GR. The detection result combined by the grid map creating unit33C is stored in the map storage database36as the map information MI. The matching navigation calculation unit33B specifies the position and direction of the dump truck2based on the detection result of the laser sensor24B and the map information MI stored in the map storage database36(step ST71).

The position measurement controller33determines whether the position of the dump truck2detected by the matching navigation calculation unit33B has high accuracy (step ST72). Specifically, the determining unit33A converts the GPS position detected by the GPS receiver31to the X-Y coordinate position and the position measurement controller33detects the distance (a difference distance) between the position obtained by the determining unit33A converting the GPS position to the X-Y coordinate position and the position of the dump truck2detected by the matching navigation calculation unit33B. The position measurement controller33determines that the position of the dump truck2detected by the matching navigation calculation unit33B has high accuracy when the distance between the position obtained by the determining unit33A converting the GPS position to the X-Y coordinate position and the position detected by the matching navigation calculation unit33B is equal to or smaller than a predetermined distance. The position measurement controller33determines that the position of the dump truck2detected by the matching navigation calculation unit33B does not have high accuracy when the distance between the position obtained by the determining unit33A converting the GPS position to the X-Y coordinate position and the position detected by the matching navigation calculation unit33B exceeds the predetermined distance. The predetermined distance is a distance at which the dump truck2can perform autonomous travel when the GPS position detected by the GPS receiver31is not the Fix solution.

When it is determined that the position of the dump truck2detected by the matching navigation calculation unit33B has high accuracy (step ST72: Yes), the position measurement controller33determines whether the number of the detection results detected by the laser sensor24B is sufficient (step ST73). Specifically, the position measurement controller33determines that the number is sufficient when the number of the detection results detected by the laser sensor24B is equal to or larger than a predetermined number and determines that the number is not sufficient when the number is smaller than the predetermined number. The predetermined number is a number at which the dump truck2can perform autonomous travel when the solution of the GPS position detected by the GPS receiver31is not the Fix solution.

When it is determined that the number of the detection results detected by the laser sensor24B is sufficient (step ST73: Yes), the position measurement controller33determines whether the detection result of the laser sensor24B detected by the measurement point availability determining unit39is identical to the map information MI stored in the map storage database36(step ST74). Specifically, the position measurement controller33performs pattern-matching on the detection result detected by the laser sensor24B and the map information MI stored in the map storage database36using normalized correlation and determines that the two items of data are identical when a correlation value is equal to or larger than a predetermined value while determining that the two items of data are not identical when the correlation value is smaller than the predetermined value. The predetermined value is a value at which the dump truck2can perform autonomous travel when the solution of the GPS position detected by the GPS receiver31is not the Fix solution.

When the position measurement controller33determines that the detection result of the laser sensor24B detected by the measurement point availability determining unit39is identical to the map information MI stored in the map storage database36(step ST74: Yes), the determining unit33A stores the distance between the position obtained by converting the GPS position to the X-Y coordinate position and the position of the dump truck2detected by the matching navigation calculation unit33B in a nonvolatile memory335(step ST75). In step ST75, the position measurement controller33always detects an average distance of the distance between the position obtained by the determining unit33A converting the GPS position to the X-Y coordinate position and the position of the dump truck2detected by the matching navigation calculation unit33B and stores the average distance in the nonvolatile memory335. In step ST6, the position measurement controller33corrects the detected position and direction of the dump truck2using the average distance when the matching navigation calculation unit33B specifies the position and direction of the dump truck2based on the detection result of the laser sensor24B and the map information MI stored in the map storage database36to allow the dump truck2to travel along the travel route RP.

When the position of the dump truck2detected by the matching navigation calculation unit33B does not have high accuracy (step ST72: No), when it is determined that the number of the detection results detected by the laser sensor24B is not sufficient (step ST73: No), or when it is determined that the detection result of the laser sensor24B detected by the measurement point availability determining unit39is not identical to the map information MI stored in the map storage database36(step ST74: No), the position measurement controller33determines that the position and direction of the dump truck2detected by the matching navigation calculation unit33B is not appropriate for autonomous travel and transmits a determination result to the wireless communication device18of the control facility7via the wireless communication device34. Upon receiving the determination result that the position and direction of the dump truck2is not appropriate for autonomous travel, the control facility7stores the determination result in the storage device13(step ST76).

In the position measurement controller33of the second embodiment, when it is determined that the error in the GPS position of the dump truck2detected by the GPS receiver31is equal to or smaller than the predetermined error (step ST2: Yes), the grid map creating unit33C creates the map information MI (step ST4) and the matching navigation calculation unit33B specifies the position and direction of the dump truck2and checks the accuracy of the detected position and direction (step ST7). By doing so, when the determining unit33A determines that the error in the GPS position detected by the GPS receiver31is equal to or smaller than the predetermined error, the position measurement controller33specifies the position and direction of the dump truck2by comparing the detection result of the laser sensor and the map information MI stored in the map storage database36and determines whether it is appropriate to allow the dump truck2to travel along the travel route RP based on the position of the dump truck2specified by the position measurement controller33.

Moreover, the position measurement controller33of the second embodiment stores the difference distance in step ST75. In this way, the position measurement controller33detects and stores the difference (the difference distance) between the position and direction detected by the determining unit33A and the position and direction of the dump truck2obtained by comparing the detection result of the laser sensor24B and the map information MI of the travel route RP stored in the map storage database36when the determining unit33A determines that the error in the GPS position detected by the GPS receiver31is equal to or smaller than the predetermined error.

In the second embodiment, the construction machine control system30detects a distance (difference distance) between the position of the dump truck2detected by the determining unit33A and the position of the dump truck2detected by the matching navigation calculation unit33B based on the GPS position detected by the GPS receiver31and determines whether the position and direction of the dump truck2detected by the matching navigation calculation unit33B enable autonomous travel. Due to this, the construction machine control system30can check the accuracy of the position detected by the matching navigation calculation unit33B in a period in which autonomous travel is performed in a state in which the error in the GPS position detected by the GPS receiver31is equal to or smaller than the predetermined error. As a result, in addition to the advantages of the first embodiment, the construction machine control system30can urge the operator to take countermeasures such as providing a landmark that the laser sensor24B can detect at a place where the position and direction detected by the matching navigation calculation unit33B do not allow autonomous travel and allowing the dump truck to travel several times while detecting the position of the place where autonomous travel is not allowed. Moreover, even when it is not possible to specify the position and direction using a GPS, the construction machine control system30can allow the dump truck2to travel continuously (that is, the operations of the mine can be performed continuously).

The construction machine control system30detects and stores an average distance of the distance (difference distance) between the position of the dump truck2detected by the determining unit33A and the position of the dump truck2detected by the matching navigation calculation unit33B based on the GPS position detected by the GPS receiver31. The construction machine control system30corrects the detected position and direction of the dump truck2using the average distance when the position and direction of the dump truck2are specified based on the detection result of the laser sensor24B and the map information MI stored in the map storage database36to allow the dump truck2to travel along the travel route RP. As a result, even when the position of the dump truck2detected by the determining unit33A shifts from the position of the dump truck2detected by the matching navigation calculation unit33B due to an attachment error of the laser sensor24B, and it is not possible to specify the position and direction using a GPS, the construction machine control system30can allow the dump truck2to travel continuously (that is, the operations of the mine can be performed continuously).

In the construction machine control system30of the second embodiment, when it is determined that the error in the GPS position detected by the GPS receiver31is equal to or smaller than the predetermined error (step ST2: Yes), the matching navigation calculation unit33B may detect the position, direction, and difference distance of the dump truck2, check the accuracy of the detected position and direction, and store the difference distance similarly to step ST7in at least a portion of the period in which the grid map creating unit33C creates the map information MI.

In the first and second embodiments, the navigation system30creates the map information MI and specifies the position and direction of the dump truck2based on the detection result of the laser sensor24B. In the present invention, the navigation system30may create the map information MI and specify the position and direction of the dump truck2based on the detection result of the radar24A which is a non-contact sensor. Moreover, in the present invention, the navigation system30may create the map information MI and specify the position and direction of the dump truck2based on the detection result of a plurality of charge-coupled device (CCD) cameras provided in the dump truck2, which is a non-contact sensor.

The constituent elements disclosed in the embodiments include those easily conceivable by a person of ordinary skill in the art and those substantially equivalent thereto, that is, those within the range of equivalence. Further, the constituent elements of the respective embodiments can be appropriately combined with each other. Further, some of the constituent elements may not be used.

In the embodiments, although a mining machine used in a mine has been described as an example, the present invention is not limited to this but can be applied to a construction machine used in an underground mine and a construction machine used in a working site on the ground. The construction machine includes a mining machine.

In the embodiments, although the position of the mining machine is detected using the GPS receiver31, the present invention is not limited to this but the position of the mining machine may be detected based on a well-known “position detection unit.” In particular, since the GPS cannot be detected in an underground mine, self-localization of a construction machine which uses IMES (indoor messaging system), a pseudo satellite (pseudo-lite), RFID (radio frequency identifier), a beacon, a surveying instrument, a wireless LAN, UWB (ultra wide band), SLAM (simultaneous localization and mapping), and a landmark (a mark provided to the sides of a travel route) which are existing position detection devices, for example, may be used. These position detection devices may be used in a mining machine used in a mine on the ground or a construction machine used in a working site on the ground.

Moreover, in the embodiments, although a control system for a dump truck in a mine on the ground has been described as an example of the “construction machine control system”, the present invention is not limited to this but may include a construction machine control system for a construction machine which is another mining machine used in a mine on the ground, a construction machine used in an underground mine, or a construction machine (an excavator, a bulldozer, a wheel loader, or the like) used in a working site on the ground and which includes a “position detection device”, a “non-contact sensor”, and a “position calculating unit”.

REFERENCE SIGNS LIST

30CONSTRUCTION MACHINE CONTROL SYSTEM

32A ROUTE POSITION STORAGE UNIT (ROUTE POSITION STORAGE UNIT)

RP TRAVEL ROUTE

VP VERTICAL PROJECTION

BK BANK

MI MAP INFORMATION