Mobile crane collision management system and mobile crane collision management method

Abstract

To easily manage a plurality of mobile cranes so that they do not interfere with each other.SOLUTION: A collision management system for a mobile crane has a first acquisition unit that acquires first position information measured by a first GNSS device provided at the tip of the boom of a mobile crane, a second acquisition unit that acquires second position information measured by a second GNSS device provided at the rotation center of the mobile crane, and a determination unit that determines whether or not a crane will interfere based on the distance between the tip of the boom of the first mobile crane and each of a plurality of different positions along the longitudinal axis of the boom defined by the rotation center of the first mobile crane.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a collision management system for a mobile crane and a collision management method for a mobile crane. [Background technology]

[0002] At construction sites, multiple mobile cranes may be used. The mobile cranes move to the work location by self-propelling, and perform the work by rotating and raising the boom. Since there are multiple mobile cranes, they must be managed to prevent collisions between each other. There is a system that uses a satellite positioning system to obtain three-dimensional information indicating the position of a crane, and shares the three-dimensional information between each of the cranes to prevent collisions between cranes (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-095376 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, because cranes rotate and raise / lower their booms, it is necessary to prevent collisions by taking into consideration the operating status of the boom. In this case, it is necessary to not only measure the position of the crane, but also to grasp the attitude of the boom. In order to grasp the attitude of the boom, various sensors are required, such as a rotation angle sensor for detecting the rotation angle of the boom and a boom hoisting angle sensor for detecting the boom hoisting angle. In order to attach such various sensors to the boom, it is necessary to select the installation position, and even if one tries to attach sensors to the boom of an existing crane later, it is difficult to secure the installation space.

[0005] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a mobile crane collision management system and a mobile crane collision management method that can easily manage multiple mobile cranes so that they do not interfere with each other. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, one aspect of the present invention is a collision management system for a mobile crane, comprising: a first acquisition unit that acquires first position information measured by a first GNSS device provided at the tip of a boom of a mobile crane; a second acquisition unit that acquires second position information measured by a second GNSS device provided at the rotation center of the mobile crane; and a determination unit that calculates distances between the tip of the boom of the first mobile crane and each of a plurality of different positions along the longitudinal axis of the boom, which are determined by the rotation center of the first mobile crane, based on the position indicated by the first position information obtained from the first GNSS device provided on a second mobile crane different from the first mobile crane, the first position information obtained from the first GNSS device provided on the first mobile crane, and the second position information obtained from the second GNSS device provided on the first mobile crane, and determines whether or not the first mobile crane and the second mobile crane will interfere with each other based on each of the calculated distances.

[0007] Another aspect of the present invention is a collision management method for a mobile crane, wherein a first acquisition unit acquires first position information measured by a first GNSS device provided at the tip of a boom of a mobile crane, a second acquisition unit acquires second position information measured by a second GNSS device provided at the rotation center of the mobile crane, and a determination unit determines distances between the tip of the boom of the first mobile crane and each of a plurality of different positions along the longitudinal axis of the boom, which are defined by the rotation center of the first mobile crane, based on a position indicated by the first position information obtained from a first GNSS device provided on a second mobile crane different from the first mobile crane, the first position information obtained from the first GNSS device provided on the first mobile crane, and second position information obtained from the second GNSS device provided on the first mobile crane, and determines whether or not the first mobile crane and the second mobile crane will interfere with each other based on each of the determined distances. Effect of the Invention

[0008] As described above, according to the present invention, a plurality of mobile cranes can be easily managed so as not to interfere with each other. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic block diagram showing the configuration of a collision management system S according to an embodiment of the present invention. [Diagram 2] 2 is a schematic functional block diagram illustrating the functions of a collision management system S. FIG. [Diagram 3] 2 is a schematic functional block diagram illustrating the functions of a collision management server 30. FIG. [Figure 4] 3 is a diagram showing an example of device information stored in a storage unit 301. FIG. [Diagram 5] 13 is a flowchart illustrating the operation of the collision management server 30. [Figure 6] FIG. 1 is a conceptual diagram of a work area at a construction site viewed from above in a plan view. [Figure 7]FIG. 2 is a diagram showing an example of a display screen displayed on the terminal device T1. [Figure 8] FIG. 2 is a diagram showing an example of a display screen displayed on the terminal device T1. [Figure 9] 1 is a diagram showing the relationship between the position at which the antenna of the GNSS device is provided on a crane, the tip of the boom, and the boom's rotation center point. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A collision management system according to an embodiment of the present invention will now be described with reference to the drawings. FIG. 1 is a schematic block diagram showing the configuration of a collision management system S according to an embodiment of the present invention. The collision management system S includes a crane CR1, a crane CR2, a network N, a collision management server 30, a Web server 40, and a terminal device 50. The crane CR1 and the crane CR2 are each a mobile crane and are self-propelled. The crane CR1 is provided with a first GNSS device 1a, a second GNSS device 1b, and a terminal device T1. The first GNSS device 1a is provided at the tip of the boom B1 of the crane CR1. The second GNSS device 1b and the terminal device T1 are provided at the main body of the crane CR1. Here, GNSS is a global navigation satellite system. The boom is sometimes called a jib. The crane CR2 is provided with a first GNSS device 2a, a second GNSS device 2b, and a terminal device T2. The first GNSS device 2a is provided at the tip of the boom B2 of the crane CR2. The second GNSS device 2b and the terminal device T2 are provided at the main body of the crane CR2. The second GNSS antenna may be provided on the boom side of the crane's rotation center and at the rear side of the operator's cab.

[0011] The network N connects various communication devices so that they can communicate with each other. The collision management server 30 is connected via a network N to the terminal device T1 and the terminal device T2. The collision management server 30 determines whether or not the cranes CR1 and CR2 will interfere with each other, based on the first position information and the second position information obtained from the terminal device T1 and the terminal device T2, respectively. The collision management server 30, the Web server 40, and the terminal device 50 are connected via a network N so as to be able to communicate with each other.

[0012] FIG. 2 is a schematic functional block diagram illustrating the function of the collision management system S. In FIG. 2, the collision management system S is shown for a crane CR1 and a cloud CLD, and a crane CR2 is omitted from the illustration because it has the same configuration as the crane CR1. The crane CR1 includes a cab CAB, a main body MB, and a boom B1. The driver's cab CAB is provided with a communication unit U1 and a terminal device T1. The communication unit U1 includes a power supply device PD, an LTE router RT1, and a PoE router RT2. The power supply device PD is connected to a power supply socket provided inside the driver's cab via a connector CN0 and receives power from an external source. The power supply socket may be, for example, a cigarette lighter socket. The power supply device PD converts the power supplied via the power supply socket into a voltage compatible with the LTE router RT1 and supplies the power, and also converts the power into a voltage compatible with the PoE router RT2 and supplies the power.

[0013] The LTE router RT1 is connected to the PoE router RT2 so as to be able to communicate with the PoE router RT2. The LTE router RT1 communicates with the PoE router RT2 in accordance with the communication standard LTE (Long Term Evolution). The LTE router RT1 transmits data (eg, location information) obtained from the PoE router RT2 via the network N to the collision management server 30 of the cloud CLD.

[0014] The PoE router RT2 is communicatively connected to the LTE router RT1. The PoE router RT2 is communicatively connected to the first GNSS device 1a via a LAN (Local Area Network) cable. Here, the PoE router RT2 and the first GNSS device 1a are connected to each other by connecting a plurality of LAN cables between the PoE router RT2 and the first GNSS device 1a via a LAN extension connector CN1 and a LAN extension connector CN2. The PoE router RT2 is communicatively connected to the second GNSS device 1b via a LAN cable. Here, the PoE router RT2 and the second GNSS device 1b are connected to each other by connecting a plurality of LAN cables between the PoE router RT2 and the second GNSS device 1b via a LAN extension connector CN3 and a LAN extension connector CN4. These LAN cables are PoE-compatible LAN cables.

[0015] Here, the cab CAB belongs to the main body MB and is provided at any position in the main body MB. The first GNSS device 1a is provided at the tip of the boom B1, and the second GNSS device 1b is provided in the main body MB. For example, the second GNSS device 1b is provided at the rotation center (or center point) of the crane CR1 when the main body MB is viewed in a plan view. Therefore, the distance between the first GNSS device 1a and the PoE router RT2 is longer than the distance between the second GNSS device 1b and the PoE router RT2. The LAN cable between the first GNSS device 1a and the PoE router RT2 is a LAN cable that can be installed outdoors, and can be used up to a length of, for example, about 100 m. The PoE router RT2 supplies power to the first GNSS device 1a and the second GNSS device 1b by PoE (Power over Ethernet), and communicates with each of the first GNSS device 1a and the second GNSS device 1b. The PoE router RT2 acquires the first location information measured by the first GNSS device 1a, and the second location information measured by the second GNSS device 1b.

[0016] The terminal device T1 may be any one of a tablet, a smartphone, a PC (personal computer), etc. The terminal device T1 is wirelessly connected to the collision management server 30 via the network N so as to be able to communicate with the collision management server 30. The terminal device T1 is provided with a display screen. The terminal device T1 is installed in a position where the display screen can be viewed by an operator in the cab.

[0017] The first GNSS device 1a includes a PoE splitter 11a, a microcomputer 12a, a GNSS module 13a, and a GNSS antenna 14a. The PoE splitter 11a is connected to the PoE router RT2 and supplies power provided by PoE to the microcomputer 12a. The PoE splitter 11a also supplies data transmitted from the PoE router RT2 to the microcomputer 12a, and supplies data supplied from the microcomputer 12a to the PoE router RT2.

[0018] The microcomputer 12a is connected to the GNSS module 13a and the PoE splitter 11a. The microcomputer 12a transmits the first position information obtained from the GNSS module 13a together with device identification information assigned to the microcomputer 12a to the PoE router RT2 via a LAN cable. The GNSS module 13a is connected to the GNSS antenna 14a and to the microcomputer 12a. The GNSS module 13a generates first position information representing the position of the GNSS module 13a based on a signal received by the GNSS antenna 14a, and outputs the generated first position information to the microcomputer 12a. The GNSS module 13a generates the first position information at regular intervals. The regular intervals may be every few seconds. The GNSS antenna 14a receives satellite signals from GNSS satellites.

[0019] The second GNSS device 1b includes a PoE splitter 11b, a microcomputer 12b, a GNSS module 13b, and a GNSS antenna 14b. The PoE splitter 11b is connected to the PoE router RT2 and supplies power provided by PoE to the microcomputer 12b. The PoE splitter 11b also supplies data transmitted from the PoE router RT2 to the microcomputer 12b, and supplies data supplied from the microcomputer 12b to the PoE router RT2.

[0020] The microcomputer 12b is connected to the GNSS module 13b and the PoE splitter 11b. The microcomputer 12b transmits the second position information obtained from the GNSS module 13b to the PoE router RT2 via a LAN cable together with device identification information assigned to the microcomputer 12b. The device identification information is assigned to the microcomputer 12b in advance and is identification information for individually identifying the device. The GNSS module 13b is connected to the GNSS antenna 14b and to the microcomputer 12b. The GNSS module 13b generates second position information representing the position of the GNSS module 13b based on a signal received by the GNSS antenna 14b, and outputs the generated second position information to the microcomputer 12b. The GNSS module 13b generates the second position information at regular intervals. The regular intervals may be every few seconds. The GNSS antenna 14b receives satellite signals from GNSS satellites.

[0021] The cloud CLD includes a collision management server 30 and a Web server 40 . The collision management server 30 receives the first location information and the second location information transmitted from the LTE router RT1, performs collision calculation, and transmits the result of the collision calculation to the terminal device T1. The Web server 40 supplies various data to the terminal device T1.

[0022] FIG. 3 is a schematic functional block diagram illustrating the functions of the collision management server 30. As shown in FIG. The collision management server 30 includes a memory unit 301 , a communication unit 302 , a first acquisition unit 303 , a second acquisition unit 304 , an attitude calculation unit 305 , a determination unit 306 , a determination result output unit 307 , and a control unit 308 . The storage unit 301 stores various data. For example, the storage unit 301 stores device information. The memory unit 301 is configured with a storage medium, for example, a hard disk drive (HDD), a flash memory, an electrically erasable programmable read only memory (EEPROM), a random access read / write memory (RAM), a read only memory (ROM), or any combination of these storage media. The storage unit 301 may be, for example, a non-volatile memory.

[0023] The communication section 302 communicates with the communication units (eg, communication unit U1) provided on each of the cranes CR1 and CR2. The first acquisition unit 303 acquires first position information measured by a first GNSS device provided at the tip of the boom of the mobile crane. The second acquisition unit 304 acquires second position information measured by a second GNSS device provided at the rotation center of the mobile crane.

[0024] The attitude calculation unit 305 determines the position of the mobile crane and the direction of the boom based on the first position information and the second position information. The determination unit 306 performs collision calculations and determines whether or not a first mobile crane (eg, crane CR1) and a second mobile crane (eg, crane CR2) will interfere with each other based on the calculation results. The determination result output unit 307 transmits the determination result determined by the determination unit 306 to output devices (e.g., terminal device T1) provided on the first mobile crane and the second mobile crane, respectively, via the communication unit 302 so that the determination result can be output. Here, the determination result output unit 307 may transmit the result of a determination as to whether or not the crane will interfere with other cranes to a terminal device provided on the destination crane among multiple cranes present in the work area of ​​the construction site. This allows the operator to know whether or not the crane he or she is operating is likely to interfere with other cranes. The control unit 308 controls each unit of the collision management server 30 .

[0025] Next, FIG. 4 is a diagram showing an example of device information stored in the storage unit 301. As shown in FIG. The equipment information includes crane identification information, GNSS device identification information, position information, and terminal device identification information. The crane identification information is identification information that identifies each mobile crane that is used at a construction site and is the target of collision management by the collision management server 30. The crane identification information is assigned in advance to each mobile crane. The GNSS device identification information is identification information for individually identifying each GNSS device. The GNSS device identification information may be assigned in advance, or device identification information assigned to the microcomputer of the GNSS device may be used. The position information is the position information received from each GNSS device. The terminal device identification information is identification information that individually identifies the terminal device provided on each mobile crane.

[0026] For example, the crane identification information "1001" is associated with the GNSS device identification information "G101" and "G102", and is also associated with the terminal device identification information "T101". This shows that the mobile crane assigned the crane identification information "1001" is equipped with a first GNSS device assigned with GNSS device identification information "G101", a second GNSS device assigned with GNSS device identification information "G102", and a terminal device assigned with terminal device identification information "T101". Then, the position information received from the first GNSS device is stored in association with the GNSS device identification information "G101", and the position information received from the second GNSS device is stored in association with the GNSS device identification information "G201". Also, here, whether the GNSS device indicated by the GNSS device identification information is provided at the tip of the boom or at the boom rotation center may be stored in association with the GNSS device identification information. In this way, based on the GNSS device identification information, it is possible to know whether the position information indicates the position of the tip of the boom or the position of the boom rotation center.

[0027] The communication unit 302, the first acquisition unit 303, the second acquisition unit 304, the attitude calculation unit 305, the judgment unit 306, the judgment result output unit 307, and the control unit 308 may be composed of a processing unit such as a CPU (Central Processing Unit) or a dedicated electronic circuit.

[0028] Next, the operation of the collision management system S will be described. Fig. 5 is a flow chart for explaining the operation of the collision management server 30. Fig. 6 is a conceptual diagram showing a working area of ​​a construction site where a crane CR1 and a crane CR2 are present, as viewed from above in a plan view. When the cranes CR1 and CR2 are in operation, the communication unit U1 provided in the crane CR1 acquires first position information based on the result of positioning by the first GNSS device 1a from the first GNSS device 1a, and acquires second position information based on the result of positioning by the second GNSS device 1b from the second GNSS device 1b. Then, the communication unit U1 provided in the crane CR1 transmits the first position information and the second position information to the collision management server 30. Similarly, the communication unit provided in the crane CR2 transmits the first position information and the second position information to the collision management server 30. Such transmission of position information is performed at regular time intervals (for example, every few seconds).

[0029] The communication unit 302 of the collision management server 30 receives the position information transmitted from each communication unit (step S101 in FIG. 5). When the position information is received, the collision management server 30 stores the received position information in the storage unit 301 (step S102 in FIG. 5). More specifically, the first acquisition unit 303 of the collision management server 30 acquires the first position information measured by the first GNSS device 1a and writes it to the storage unit 301, and also acquires the first position information measured by the first GNSS device 2a and writes it to the storage unit 301. The second acquisition unit 304 acquires the second position information measured by the second GNSS device 1b and writes it to the storage unit 301, and also acquires the second position information measured by the second GNSS device 2b and writes it to the storage unit 301.

[0030] When the position information is stored, the determination unit 306 performs a collision calculation. Here, the determination unit 306 determines a plurality of different positions (target positions) along the longitudinal axis of the boom, which is determined by the tip of the boom of the crane CR2 and the rotation center of the crane CR2, based on the first position information obtained from the first GNSS device 1a provided on the crane CR1 and the second position information obtained from the second GNSS device 1b provided on the crane CR1 (FIG. 5, step S103). Here, in Fig. 6, an axis AX1 in the longitudinal direction of the boom of the crane CR1 is shown. The determination unit 306 sets target positions along the axis AX1. The target positions may be arranged at regular intervals along the axis AX1. Here, the target positions are set from target position P1 to target position P14. Target position P1 is a position corresponding to the rotation center of the crane CR1, and target position P14 is a position corresponding to the tip of the boom of the crane CR1.

[0031] Next, the determination unit 306 determines the distance between the position PE indicated by the first position information obtained from the first GNSS device 2a provided on the crane CR2, which is a mobile crane different from the crane CR1, and each target position (P1 to P14) of the crane CR1 (Figure 5, step S104).

[0032] When each distance is calculated, the determination unit 306 determines whether or not the crane CR1 and the crane CR2 will interfere with each other based on each calculated distance. For example, the determination unit 306 extracts the minimum distance from each calculated distance (step S105 in FIG. 5), and determines whether or not there will be interference based on the extracted minimum distance. For example, here, it is extracted that the distance L6 between the position PE of the tip of the boom of the crane CR2 and the target position P6 is the minimum distance from among multiple target positions (P1 to P14).

[0033] Then, the determination unit 306 determines whether the extracted minimum distance is smaller than a reference value (step S106 in FIG. 5). The reference value is a predetermined value, and may be stored in the storage unit 301 and read out when the determination unit 306 makes a determination. When the minimum distance is smaller than the reference value (FIG. 5, step S106-YES), the determination unit 306 generates, as a determination result, alert information indicating that the cranes CR1 and CR2 are approaching within a certain range (FIG. 5, step S107). When the alert information is generated, the determination result output unit 307 generates display screen data (FIG. 5, step S108), and transmits the display screen data and the alert information, which is the determination result, to each terminal device (FIG. 5, step S109).

[0034] On the other hand, in step S106, if the minimum distance is equal to or greater than the reference value (FIG. 5, step S106-NO), the determination unit 306 skips the process of generating alert information in step S107. Here, the determination unit 306 may deliver data indicating that there is no alert information to the determination result output unit 307 as the determination result. When the generation of alert information is skipped, the determination result output unit 307 generates display screen data (FIG. 5, step S108) and transmits the display screen data to each terminal device (FIG. 5, step S109). When transmitting the display screen data, the determination result output unit 307 may also transmit data indicating that there is no alert information.

[0035] The above-described process of FIG. 5 may be executed every time a certain period of time elapses, or may be executed every time location information is received. This allows collision determination to be performed each time the position is measured by the first GNSS device and the second GNSS device, even if the attitude of the boom is changed for at least either the crane CR1 or the crane CR2, such as when the boom is raised (raised), lowered (tied down), rotated, moved (traveled), etc. By shortening the interval at which the positions are measured, the determination result as to whether or not the cranes will interfere can be output to the terminal device in close to real time.

[0036] 7 and 8 are diagrams showing an example of a display screen displayed on the terminal device T1, and are plan views of a crane present in a work area at a construction site as viewed from above. FIG. 7 shows an example of a display screen when the alert information is not displayed, and FIG. 8 shows an example of a display screen when the alert information is displayed. In Fig. 7 and Fig. 8, the position of the boom is displayed according to the attitude of the boom of the crane on which the terminal device T1 is installed (Fig. 7 and Fig. 8, reference numeral 700). Here, the orientation of the display screen is set so that the top of the display screen is north. A linear figure imitating the boom is displayed, arranged so that the boom's swivel center is the center of the display screen, and oriented according to the boom's swivel angle. A circle (reference numeral 701) is displayed, which has the boom length as its radius and represents the swivel range centered on the boom's swivel center. A figure (reference numeral 702) indicating the direction of other cranes present in the vicinity of the crane is arranged on the outer periphery of the circle. Based on the contents of this display, the operator can grasp the direction of the boom of the crane and the range of the boom when it is swung at the current crane position. The operator can also grasp the direction of other cranes present in the vicinity.

[0037] Furthermore, depending on the current position of the other crane and the length of the boom, a circle (750) indicating the rotation range of the other crane is displayed. From the positional relationship between the circle (701) indicating the rotation range of the own crane and the circle (750) indicating the rotation range of the other crane, the operator can grasp whether or not there is a possibility of interference between the own crane and the other crane. In this way, the determination result output unit 307 generates data for drawing a circle indicating the turning range, a straight line imitating a boom, and the like on the display screen, and transmits this to each terminal device via the communication unit 302.

[0038] In addition, since no alert information is displayed in FIG. 7, the operator can understand that there is a low possibility that the crane itself will interfere with another crane. On the one hand, as shown in FIG. 8, alert information is being displayed. Here, as the alert information, the background color of the display screen is displayed in a display mode different from that when the alert information is not displayed. For example, when the alert information is not displayed, the background color is white, but when the alert information is displayed, the alert information is displayed by displaying the background color in any one of colors such as red, orange, and yellow. Here, since the alert information is displayed by making the display mode of the background color different, it is possible to easily grasp the occurrence of the alert information, that is, the possibility that the own crane and other cranes interfere with each other.

[0039] In the embodiment described above, the determination unit 306 determines whether to output alert information based on whether the minimum value of the distances between the position PE of the tip of the boom of the second mobile crane and each target position of the boom of the first mobile crane is smaller than the reference value. However, a plurality of different reference ranges may be used, and based on whether the minimum value falls within any of the reference ranges, the alert information may be output. For example, as the reference ranges, a first range is less than La (m: meter), a second range is equal to or more than La (m) and less than Lb (m), a third range is equal to or more than Lc (m) and less than Ld (m), and a fourth range is equal to or more than Ld (m) are stored in the storage unit 301 in advance (however, La < Lb < Lc < Ld). Then, the determination unit 306 determines which range the minimum value obtained this time corresponds to. And the determination unit 306 may output no alert information or alert information indicating the lowest alert level (level 0) when the minimum value corresponds to the fourth range (level 0). Further, the determination unit 306 may output alert information indicating level 1 when the minimum value corresponds to the third range, level 2 when the minimum value corresponds to the second range, and level 3 when the minimum value corresponds to the first range.

[0040] In this case, the judgment result output unit 307 transmits an alert level, one of levels 0 to 3, as alert information to the terminal device depending on the judgment result. As a result, when the alert level is level 0, the background of the display screen of the terminal device is displayed in white, making it possible to understand that there is a low possibility of interference. Then, when the minimum value falls within the third range (level 1), the background color is displayed in yellow, when it falls within the second range (level 2), the background color is displayed in orange, and when it falls within the first range (level 3), the background color is displayed in red. As a result, the judgment result output unit 307 can display the cranes in different display modes depending on the degree to which they are approaching each other.

[0041] Also, although the case where the judgment result output unit 307 transmits the judgment result to a terminal device has been described, the judgment result may be transmitted to an output device provided in each crane (CR1, CR2). The output device may be any device that can output the judgment result in a manner that allows the judgment result to be understood. The output device may be, for example, the above-mentioned terminal device, or may be any of a buzzer and a rotating light. The buzzer is installed near the driver's cab and emits a buzzer sound when the determination result indicates that there is alert information. This allows the operator to know that the cranes are approaching each other based on the buzzer sound. The buzzer may output a buzzer sound at a different volume depending on the alert level, or may output a buzzer sound of a type depending on the alert level. The type of sound may be a ringing pattern in which a ringing period during which the buzzer sounds and a silent period during which the buzzer does not sound are repeated, and at least one of the ringing period and the silent period may be different to output a buzzer sound depending on the alert level.

[0042] The rotating light is provided in a position near the cab that is visible to the operator, or in a position that is visible to workers and managers around the crane, and when there is alert information as a result of the determination, the light source is turned on and the reflector provided around the light source is rotated to emit light. This allows the operator, surrounding contractors, managers, etc. to visually recognize the light and know that the cranes are approaching each other. The rotating light may also be configured to emit light in different colors depending on the alert level. For example, the rotating light may not be turned on at level 0, may emit yellow light at level 1, may emit orange light at level 2, and may emit red light at level 3.

[0043] In the above-described embodiment, the determination unit 306 determines whether to output alert information based on whether the minimum value of the distance between the position PE of the tip of the boom of the second mobile crane and each target position of the boom of the first mobile crane is smaller than a reference value, but the value used for the determination does not have to be only the minimum value. For example, the determination unit 306 may count the number of distances to each target position that are smaller than a reference value, and determine whether interference will occur depending on the number. For example, the determination unit 306 may not output alert information (or output alert information indicating the lowest level) when the number of distances to each target position that are smaller than the reference value is 0. The determination unit 306 may also output alert information indicating a higher level as the number of distances to each target position that are smaller than the reference value increases beyond 1. This makes it possible to grasp the extent of the range of the area where interference may occur.

[0044] In the above embodiment, the determination unit 306 determines whether to output alert information based on whether the position PE of the tip of the boom of the second mobile crane and the minimum value of the distance between each target position of the boom of the first mobile crane are smaller than a reference value, but the determination unit 306 may determine whether to output alert information based on whether the position PE of the tip of the boom of the first mobile crane and the minimum value of the distance between each target position of the boom of the second mobile crane are smaller than a reference value. In addition, when there are three or more mobile cranes in the work area of ​​the construction site, the determination unit 306 may perform a collision calculation for each combination of cranes.

[0045] In the above embodiment, the determination unit 306 determines the distance between each target position and the position PE of the tip of the boom, but the distance may be determined in order from the tip of the boom or the boom's swing center, and if a distance greater than the previous distance is determined, the distance to the subsequent target position is not determined. This eliminates the need to calculate the distance after the minimum value, thereby shortening the time required to obtain the determination result.

[0046] In the above-described embodiment, the second GNSS device (1b, 2b) is provided at the rotation center of the crane, but it may be provided at the rotation center point of the rotation center, or it may be provided near the rotation center point if it is difficult to provide the device at the rotation center point itself. In this case, the second position information may be corrected based on the positional relationship between the rotation center point and the second GNSS device. In addition, the first GNSS device (1a, 2a) has been described as being installed at the tip of the boom, but if it is difficult to install it at the most distal end of the boom, it may be installed near the most distal end. In this case, the second position information may be corrected based on the relationship between the most distal end of the boom and the position where the first GNSS device is installed.

[0047] Fig. 9 is a diagram showing the relationship between the position where the antenna of the GNSS device is provided on the crane, the tip of the boom, and the boom rotation center point, which are shown on a plane when the crane is viewed from above. For example, after attaching the first GNSS device to the tip of the boom, the distance c in the X-axis direction (left-right direction when looking at Figure 9) and the distance d in the Y-axis direction (up-down direction when looking at Figure 9) are measured at position 900 of the tip of the boom and position 901 of the antenna of the first GNSS device. After attaching the second GNSS device to the boom's rotation center point, the distance a in the X-axis direction and the distance b in the Y-axis direction are measured at the boom's rotation center point position 910 and the antenna position 911 of the second GNSS device.

[0048] The orientation calculation section 305 can determine the angles α, β, radius r1, and radius r2 based on the following equations. The angle α is the angle between a line passing through the position 901 of the antenna of the first GNSS device and the position 911 of the antenna of the second GNSS device, and a line passing through the position 910 of the boom's rotation center point and the position 911 of the antenna of the second GNSS device. The angle β is the angle between a line passing through the position 901 of the antenna of the first GNSS device and the position 911 of the antenna of the second GNSS device, and a line passing through the position 900 of the tip of the boom and the position 901 of the antenna of the first GNSS device. Radius r1 is the distance between position 910 of the boom's pivot point and position 911 of the antenna of the second GNSS device. Radius r2 is the distance between position 900 of the tip of the boom and position 901 of the antenna of the first GNSS device.

[0049] α = arctan(a / b) - arcsin((ac) / R) β = arctan(c / d) - arcsin((ac) / R) r1=sqrt(a*a+b*b) r2=sqrt(c*c+d*d)

[0050] The above R is the distance between the antenna position 901 of the first GNSS device and the antenna position 911 of the second GNSS device. In finding the distance R, if the position 901 on the plane is (X1, Y1) and the position 911 on the plane is (X2, Y2), then the distance R can be calculated based on the following formula. R=sqrt((X2-X1)×(X2-X1)+(Y2-Y1)×(Y2-Y1)) In this manner, the data required to correct the position can be prepared.

[0051] Once the angles α, β, radius r1, and radius r2 are determined, and the position (X1, Y1) and position (X2, Y2) are obtained at predetermined time intervals from the communication unit U1 mounted on the crane at the target time for collision calculation, the attitude calculation unit 305 can sequentially correct these based on the following equations to determine the position (X1', Y1') on the plane of the corrected position 901 and the position (X2', Y2') on the plane of the position 911. X1'=X1+r1cos(α)cos(θ)+r1sin(α)sin(θ) Y1'=Y1+r1cos(α)sin(θ)-r1sin(α)cos(θ) X2'=X2+r2cos(β)cos(θ)+r2sin(β)sin(θ) Y2'=Y2+r2cos(β)sin(θ)-r2sin(β)cos(θ) θ=arctan((Y2-Y1) / (X2-X1)) Then, the determination unit 306 of the collision management server 30 performs collision calculation based on the positions (X1', Y1') and (X2', Y2') to determine whether the cranes will interfere with each other. When the collision calculation is performed in the terminal devices (T1, T2) instead of the collision management server 30, the control unit 308 of the collision management server 30 sequentially transmits the determined positions (X1', Y1') and (X2', Y2') to the terminal devices (T1, T2). As a result, the terminal devices (T1, T2) can sequentially receive the positions (X1', Y1') and (X2', Y2') transmitted from the collision management server 30, perform collision determination, and output the determination result.

[0052] As a result, when the first position information measured by the first GNSS and the second position information measured by the second GNSS are acquired, the first position information and the second position information may be corrected based on the above formula. This allows for accurate determination even when it is difficult to install the second GNSS device (1b, 2b) at the very center of rotation of the crane or when it is difficult to install the first GNSS device (1a, 2a) at the most distal end of the tip of the boom.

[0053] According to the embodiment described above, the first GNSS device is supplied with power by being connected via a LAN cable to a PoE router provided in the main body of the mobile crane on which the first GNSS device is provided. As a result, when power is supplied to the first GNSS device by a battery or the like, the battery needs to be replaced every time the battery runs out of power, but since power can be supplied from the PoE router by PoE, there is no need to replace the battery. In addition, even if the length of the LAN cable used here is about 100 m, communication and power supply are possible, so it is easy to handle even if the boom is long.

[0054] In the above embodiment, the determination result is output using any one of the terminal device, the buzzer, the rotating light, etc., but the result may be output to the terminal device 50. The terminal device 50 may be provided in a site office or the like provided at the construction site. This allows the manager of the construction site, etc., at the site office to know whether interference will occur with each crane or not.

[0055] In the above embodiment, the functions of the first acquisition unit 303, the second acquisition unit 304, the attitude calculation unit 305, the determination unit 306, and the determination result output unit 307 are provided in the collision management server 30, and the collision calculation is performed in the collision management server 30. However, these functions may be provided in at least one of the terminal device T1 or the terminal device T2, and the collision calculation may be performed. In this case, the collision management server 30 distributes position information obtained from each crane to the terminal device that performs the collision calculation. This allows the collision calculation to be performed in the terminal device T1 or the terminal device T2. For example, the attitude calculation unit 305 of the collision management server 30 calculates the position of the tip of the boom of each crane and the position of the boom's rotation center, and the communication unit 302 transmits data indicating these positions to the terminal device. The terminal device then receives the position of the tip of the boom of each crane and the position of the boom's rotation center from the collision management server 30, and based on this position information, the functions of the determination unit 306 and the determination result output unit 307 described above may be used to determine the position of the tip of each crane and multiple different positions (target positions) along the longitudinal axis of the boom of other cranes, and perform collision determination processing. In this case, the storage unit 301 of the collision management server 30 does not need to store terminal device identification information.

[0056] The communication unit 302, the first acquisition unit 303, the second acquisition unit 304, the attitude calculation unit 305, the determination unit 306, the determination result output unit 307, and the control unit 308 in the above-mentioned embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded in a computer-readable recording medium, and the program recorded in the recording medium may be read into a computer system and executed to realize the function. Note that the "computer system" here includes hardware such as an OS and peripheral devices. Furthermore, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, an optical magnetic disk, a ROM, a CD-ROM, and a storage device such as a hard disk built into a computer system. Furthermore, the "computer-readable recording medium" may also include a medium that dynamically holds a program for a short period of time, such as a communication line when a program is transmitted via a network such as the Internet or a communication line such as a telephone line, and a medium that holds a program for a certain period of time, such as a volatile memory inside a computer system that is a server or client in that case. Furthermore, the above program may be for realizing part of the functions described above, or may be capable of realizing the functions described above in combination with a program already recorded in a computer system, or may be realized using a programmable logic device such as an FPGA (Field Programmable Gate Array).

[0057] Although an embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and designs that do not deviate from the gist of the present invention are also included. [Explanation of symbols]

[0058] 1a,2a 1st GNSS device 1b,2b 2nd GNSS device 11a,11b PoE splitter 12a, 12b Microcomputer 13a,13b GNSS Module 14a, 14b GNSS antenna 30 Collision Management Server 40 Web Server 50,T1,T2 terminal equipment 301 Storage section 302 Communications Department 303 First acquisition part 304 Second Acquisition Department 305 Posture calculation section 306 Judgment section 307 Judgment result output unit 308 Control Unit B1, B2 boom CAB Driver's cab CLD Cloud CN0 Connector CN1, CN2, CN3, CN4 LAN extension connector CR1,CR2 Crane MB Main unit N Network PD power supply RT1 LTE Router RT2 PoE Router S Collision Management System U1 Communication unit

Claims

1. A first acquisition unit that acquires first position information measured by a first GNSS device provided at a tip of a boom of the mobile crane; A second acquisition unit that acquires second position information measured by a second GNSS device provided at a rotation center of the mobile crane; a position indicated by first position information obtained from a first GNSS device provided on a second mobile crane different from the first mobile crane; determining distances between a tip of a boom of the first mobile crane and each of a plurality of different positions along a longitudinal axis of the boom, the distance being determined by a rotation center of the first mobile crane, based on first position information obtained from a first GNSS device provided on the first mobile crane and second position information obtained from a second GNSS device provided on the first mobile crane; a determination unit that determines whether or not the first mobile crane and the second mobile crane will interfere with each other based on each of the determined distances; A collision management system for a mobile crane.

2. The determination unit is Whether or not there is interference is determined based on the minimum distance among the distances obtained. A collision management system for a mobile crane according to claim 1.

3. a determination result output unit that transmits the determined result to an output device provided on each of the first mobile crane and the second mobile crane so that the determined result can be output; The collision management system for a mobile crane according to claim 1, further comprising:

4. The first GNSS device is supplied with power by being connected via a LAN cable to a PoE router provided in the main body of the mobile crane on which the first GNSS device is provided. A collision management system for a mobile crane according to claim 1.

5. a first acquisition unit acquires first position information measured by a first GNSS device provided at a tip of a boom of the mobile crane; A second acquisition unit acquires second position information measured by a second GNSS device provided at a rotation center of the mobile crane, The determination unit: a position indicated by first position information obtained from a first GNSS device provided on a second mobile crane different from the first mobile crane; determining distances between a tip of a boom of the first mobile crane and each of a plurality of different positions along a longitudinal axis of the boom, the distance being determined by a rotation center of the first mobile crane, based on first position information obtained from a first GNSS device provided on the first mobile crane and second position information obtained from a second GNSS device provided on the first mobile crane; Based on the calculated distances, it is determined whether or not the first mobile crane and the second mobile crane interfere with each other. How to manage collisions on a mobile crane.

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