RTG crane, measurement system, and measurement method

Abstract

An RTG crane according to the present invention travels on a travel path, and comprises: a detection unit that detects the distance and the angle to an object which is present on the forward side in the traveling direction of the RTG crane; a search unit that searches for an observation point within a search range by the detection unit; an observation line setting unit that sets an observation line on the basis of a plurality of observation points which have been observed by the search unit; and an inclination acquisition unit that acquires the inclination of the RTG crane with respect to the travel path on the basis of the observation line.

Description

RTG crane, measurement system, and measurement method

[0001] The present disclosure relates to an RTG crane, a metrology system, and a metrology method.

[0002] Patent Document 1 describes the automation of part of the container transport work in a container yard. A crane that transports a container travels on a linear travel path.

[0003] Japanese Patent Application Laid-Open No. 2004-123367

[0004] In the above-described crane, a sensor may be provided to detect an object present in the travel path to prevent the object from coming into contact with the crane's running section when the object is present in the travel path. The sensor has a detection range set to detect only objects in the travel path. In the case of an RTG crane, the RTG crane traveling on the travel path may rotate in an azimuth direction from its original traveling direction, causing the sensor's detection range to deviate from its original position. This is referred to as "tilting" in this specification. In such cases, the accuracy of detecting the position of an object on the travel path may decrease. To address this issue, tilting of the RTG crane may be suppressed by providing guide lines or the like on the travel path and providing a sensor on the RTG crane that reads the lines. However, this configuration requires the provision of additional guide lines or the like on the travel path. Thus, there has been a demand for an easy improvement in the accuracy of detecting the position of an object without providing a special mechanism in the environment.

[0005] An object of the present disclosure is to provide an RTG crane, a measurement system, and a measurement method that can easily improve the accuracy of detecting the position of an object.

[0006] An RTG crane according to one aspect of the present disclosure is an RTG crane that travels on a travel path, and includes a detection unit that detects the distance and angle between the RTG crane and an object on the traveling side in the direction of travel of the RTG crane, a search unit that searches for observation points within a search range using the detection unit, an observation line setting unit that sets an observation line based on multiple observation points observed by the search unit, and an inclination acquisition unit that acquires the inclination of the RTG crane with respect to the travel path based on the observation line.

[0007] The RTG crane includes a search unit that searches for observation points within a search range using a detection unit, and an observation line setting unit that sets an observation line based on multiple observation points observed by the search unit. If an object (e.g., the side of a container) with a surface parallel to the RTG crane's travel direction is present around the RTG crane's travel path, the search unit sets the search range to search for an observation point for the object. The observation line set based on the thus obtained observation points can be used as a reference line for determining the inclination if the RTG crane's travel direction or search range is inclined relative to the travel path. Therefore, by setting the observation line based on multiple observation points observed by the search unit, the observation line can be used as a reference line for determining the inclination. Therefore, the inclination acquisition unit can accurately acquire the inclination of the RTG crane relative to the travel path based on such observation line. Furthermore, the inclination of the RTG crane can be easily determined by simply searching for observation points and setting the observation line, without the need to install guide lines or the like on the travel path. Therefore, the accuracy of object position detection by the detection unit can be improved by correcting the tilt, etc. As described above, the accuracy of object position detection can be easily improved.

[0008] The search unit may set multiple search ranges on one side of the travel direction of the RTG crane. In this case, if there are multiple rows of containers near the travel path, the search unit can set a search range for each row of containers, or if there are containers and vehicles, set a search range for each object. In this way, by setting an observation line using the search results for multiple objects, the inclination of the RTG crane can be more accurately determined.

[0009] The search unit may observe multiple observation points in time series, and if it determines that the object is a moving object, the observation line setting unit may obtain an observation line based on the observation points, if the search unit observes three or more observation points in time series, the observation line setting unit may calculate an approximation line based on those observation points and use that as the observation line, if the search unit observes two observation points in time series, the observation line setting unit may connect those observation points to create an observation line, and if the search unit observes one or less observation points in time series, the observation line setting unit may command a redo of the observation. In this case, the search unit can set an observation line based on the moving object from the results of observing multiple observation points in time series.

[0010] The search unit may simultaneously observe multiple observation points from the same object or multiple objects arranged in a row, and obtain an observation line based on the observation points. If the search unit observes three or more observation points, the observation line setting unit may calculate an approximate line based on those observation points and use this as the observation line. If the search unit observes two observation points, the observation line setting unit may connect those observation points to create an observation line. If the search unit observes one or fewer observation points, the observation line setting unit may command the observation to be redone. In this case, the search unit may set an observation line for a stationary object such as a container based on the results of simultaneously observing multiple observation points.

[0011] The observation line setting unit may obtain the residual between the observation point and the approximation line and exclude observation points whose residual is greater than a threshold. For example, if an observation point corresponding to an obstacle on the roadway has occurred, the observation line setting unit can exclude the observation point corresponding to such an obstacle.

[0012] A measurement system according to one example of the present disclosure is a measurement system that measures the positional relationship of an object located on the forward side of the traveling direction of an RTG crane traveling on a traveling path, and includes a detection unit that detects the distance and angle to the object, a search unit that searches for observation points within a search range using the detection unit, an observation line setting unit that sets an observation line based on multiple observation points observed by the search unit, and an inclination acquisition unit that acquires the inclination of the RTG crane relative to the traveling path based on the observation line.

[0013] A measurement method according to one example of the present disclosure is a measurement method for measuring the positional relationship of an object present on the forward side of the traveling direction of an RTG crane traveling on a traveling path, and includes a detection process for detecting the distance and angle to the object, a search process for searching for observation points within a search range using the detection process, an observation line setting process for setting an observation line based on multiple observation points observed in the search process, and an inclination acquisition process for acquiring the inclination of the RTG crane relative to the traveling path based on the observation line.

[0014] According to this measurement system and measurement method, it is possible to obtain the same functions and effects as those of the RTG crane described above.

[0015] According to the present disclosure, the accuracy of detecting the position of an object can be easily improved.

[0016] FIG. 1 is a plan view showing an exemplary container terminal to which an RTG crane according to an embodiment is applied. FIG. 2 is a perspective view showing an example of a group of containers to be handled and a group of adjacent containers lined up along the traveling direction of a transporting vehicle. FIG. 3 is a perspective view showing an RTG crane equipped with a crane control system according to an embodiment. FIG. 4 is a schematic plan view for explaining the relationship between an RTG crane and a traveling path of the RTG crane. FIG. 5 is a schematic plan view showing an enlarged view of a part of a detection unit. FIG. 6 is a schematic plan view showing an enlarged view of a part of a detection unit. FIG. 7 is a block diagram showing the configuration and functions of a crane control system having a measurement system according to the present embodiment. FIG. 8 is a flowchart showing the processing content of the measurement system. FIG. 9 is a flowchart showing the processing content of the measurement system. FIG. 10 is a schematic plan view for explaining the processing content of the measurement system. FIG. 11 is a schematic plan view for explaining the processing content of the measurement system. FIG. 12 is a schematic plan view for explaining the processing content of the measurement system.

[0017] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the description of the drawings, identical or corresponding elements are designated by the same reference numerals, and duplicate explanations will be omitted as appropriate. In addition, the drawings may be partially simplified or exaggerated for ease of explanation, and the dimensional ratios and the like are not limited to those shown in the drawings.

[0018] Fig. 1 is a plan view showing an exemplary container terminal 1 to which the present disclosure is applied. As shown in Fig. 1, the container terminal 1 is provided with a container yard 2 in which containers C are placed, a plurality of gantry cranes 3 that transfer the containers C to and from a docked container ship, a plurality of cranes 10 that are placed in the container yard 2 and that load and unload the containers C, and a remote control room 5 that can remotely control the plurality of cranes 10.

[0019] FIG. 2 is a perspective view showing a container C and an exemplary transport vehicle 20 in the container yard 2. The transport vehicle 20 is, for example, a truck, a freight car, a trailer, or an AGV (Automated Guide Vehicle). As shown in FIGS. 1 and 2 , the container yard 2 is provided with a storage area where a plurality of containers are stored and a travel path (track lane) for the transport vehicle 20. The crane 10 retrieves a container C from the transport vehicle 20 stopped at a predetermined position and places the container C at a predetermined address in the container yard 2. The crane 10 also retrieves a container C placed in the container yard 2 and transfers the container C to the transport vehicle 20, which then carries the container C out.

[0020] As an example, the container C is an ISO standard container. The container C has a long rectangular parallelepiped shape, and for example, the longitudinal length of the container C is 20 feet or more and 45 feet or less. The height of the container C is, for example, 8.5 feet or more and 9.5 feet or less. The containers C are stacked one or more levels high in the container yard 2. The number of levels in which the containers C are arranged is sometimes called a tier.

[0021] As shown in Fig. 1, the container yard 2 includes a plurality of lanes L on which containers C are placed, and a plurality of cranes 10 are placed. For example, one crane 10 is placed for each lane L. The number of cranes 10 placed in each lane L may be one or more.

[0022] 2 , containers C are stacked one or more levels in the container yard 2 to form a plurality of rows R. Each row R is aligned so that the longitudinal direction of the containers C constituting that row R (i.e., the containers C placed on that row R) is parallel to the longitudinal directions of the containers C constituting the other rows R and the direction of the travel path of the crane 10.

[0023] If the longitudinal direction of the containers C aligned in the container yard 2 is defined as the X direction, the lateral direction of the containers C as the Y direction, and the height direction of the containers C as the Z direction, the container yard 2 extends on an XY plane, and the containers C are stacked in the Z direction at any position on the XY plane. The X direction coincides with the traveling direction of the crane 10 in the lane L. The Y direction coincides with the lateral movement direction of the crane 10 in the lane L.

[0024] The containers C form bays B, which are groups of multiple containers lined up in the Y direction and stacked in the Z direction. A plurality of bays B lined up in the X direction are provided in the container yard 2. The bays B include, for example, a group of containers to be handled B1, which is a target bay for handling the containers C, and adjacent groups of containers B2 located on both sides of the group of containers to be handled B1 in the X direction.

[0025] In the container yard 2, the position where the container C is to be loaded is virtually set in three-dimensional space, and this virtual loading position of the container C is defined as an address (X, Y, Z). That is, the container yard 2 has a plurality of addresses (X, Y, Z) that are predetermined as areas where the container C can be loaded. In the addresses (X, Y, Z), "X" indicates the bay number, "Y" indicates the row number, and "Z" indicates the tier number.

[0026] Fig. 3 is a perspective view showing an example of a crane 10 according to this embodiment, which is arranged in a container yard 2. As shown in Fig. 3, the crane 10 is a container handling crane that loads and unloads containers C. In this embodiment, a rubber-tired gantry crane (RTG) is shown as an example of the crane 10. The crane 10 automatically loads and unloads containers C arranged in the container yard 2 at the container terminal 1, for example.

[0027] The crane 10 includes, for example, a pair of legs 11, a crane girder 12 connecting the upper ends of the pair of legs 11, a trolley 13 that can travel laterally on the crane girder 12, a spreader 14 that loads and unloads the container C, and a pair of traveling sections 15A, 15B having wheels 23. The pair of legs 11 and the crane girder 12 are portal-shaped. The crane 10 includes, for example, two sets of portal-shaped pairs of legs 11 and crane girders 12, and the two sets are arranged side by side in the X direction.

[0028] The trolley 13 moves laterally in the Y direction by, for example, driving a traverse motor. In this embodiment, the Y direction coincides with the traverse direction of the trolley 13. As an example, the trolley 13 has a winding drive unit 16 including a drum that rotates forward and backward by a drum drive motor, and suspends the spreader 14 via suspension members 18 including wires. The suspension members 18 extend from the trolley 13 at two positions aligned in the X direction, and the spreader 14 is suspended from the suspension members 18 at two positions aligned in the X direction.

[0029] The spreader 14 is a hoisting device that suspends the container C. The spreader 14 has, for example, a rectangular shape extending in the X direction. The spreader 14 can latch the container C from above and loads and unloads the container C by latching and lifting the container C. For example, the operation of the spreader 14 is controlled by the drive of the traverse motor and drum drive motor described above, and the drive of the traverse motor and drum drive motor is controlled by the crane control system 150 according to this embodiment.

[0030] The running units 15A, 15B are mechanisms that travel along the linear running path of the crane 10. The crane 10 includes a pair of running units 15A, 15B provided below the legs 11 at both ends in the Y direction. Each running unit 15A, 15B includes a connecting member 21 that connects the legs 11 spaced apart in the X direction, and a plurality of wheel units 22 provided below the connecting member 21. One wheel unit 22 is provided at each end of the connecting member 21 in the X direction. The wheel unit 22 includes a plurality of wheels 23 and a wheel support unit 24 that supports the wheels 23. The wheel support unit 24 supports the wheels of a pair of wheels 23 aligned in the Y direction, supporting two pairs of wheels 23 aligned in the X direction. Note that the number of wheels 23 included in each wheel unit 22 and the number of wheel units 22 included in each running unit 15A, 15B are not particularly limited.

[0031] FIG. 4 is a schematic plan view showing an example of an RTG crane 10 and its travel environment. As shown in FIG. 4 , the travel section 15A on one side in the Y direction travels on the travel path RDA. The travel section 15B on the other side in the Y direction travels on the travel path RDB. As a result, the RTG crane 10 travels in a direction parallel to the X direction, with the travel section 15A traveling linearly on the travel path RDA and the travel section 15B traveling linearly on the travel path RDB. In the following explanation, directions in absolute coordinates based on the travel paths RDA and RDB will be described using the X direction and the Y direction. The direction in which the RTG crane 10 travels may be referred to as the "travel direction D1." Furthermore, the horizontal direction perpendicular to the travel direction D1 may be referred to as the "width direction D2" of the RTG crane 10.

[0032] The travel path RDA extends linearly in the X direction at one end of the RTG crane 10 in the Y direction, at a position adjacent to one side of the container storage area CS1 for containers C in the Y direction. A container storage area CS2 is provided on the other side of the travel path RDA in the Y direction. The travel path RDB extends linearly in the X direction at the other end of the RTG crane 10 in the Y direction, at a position adjacent to the other side of the Y direction, with the container storage area CS1 and vehicle travel path VR1 in between. Vehicle travel paths VR1 and VR2 on which vehicles travel are provided on both sides of the travel path RDB in the Y axis direction. The width of the travel paths RDA and RDB is defined as y １ , the width of the vehicle travel lane VR1 on the container storage site CS1 side is y ２ , the width of the vehicle road VR2 on the opposite side is y ３ Let's say.

[0033] Each of the travel paths RDA, RDB is set to be slightly wider in the Y direction than the dimension of the travel sections 15A, 15B in the width direction D2. Here, as shown in FIG. 4 , one side in the travel direction D1 is referred to as "direction A1," and the other side is referred to as "direction A2." At this time, the travel sections 15A, 15B can travel in the direction A1. At this time, the direction A1 corresponds to the traveling side of the travel sections 15A, 15B in the travel direction D1. Furthermore, the travel sections 15A, 15B can travel in the direction A2. At this time, the direction A2 corresponds to the traveling side of the travel sections 15A, 15B in the travel direction D1.

[0034] The RTG crane 10 includes detection units 30A, 30B, 30C, and 30D attached to the RTG crane 10. The detection units 30A, 30B, 30C, and 30D are capable of detecting the distance and angle to an object, and the type and number of sensors are not particularly limited. The sensors constituting the detection units 30A, 30B, 30C, and 30D may include millimeter-wave radar, microwave radar, LIDAR, and the like, or a combination thereof. The detection units 30A, 30B, 30C, and 30D detect the angle of an object in a horizontal plane relative to the detection units 30A, 30B, 30C, and 30D.

[0035] When the traveling units 15A, 15B are traveling with the direction A1 as their travel direction, the detection units 30A, 30B detect objects present on the travel side of the traveling units 15A, 15B in the traveling direction D1. The detection units 30A, 30B are attached to the traveling units 15A, 15B on the direction A1 side relative to the crane girder 12. The detection units 30A, 30B detect objects present in detection target areas DEA, DEB extending on the travel side (direction A1 side) in the traveling direction D1. The detection target areas DEA, DEB are set so that objects present on the traveling paths RDA, RDB within a predetermined distance on the direction A1 side as seen from the traveling units 15A, 15B can be detected where the traveling units 15A, 15B are expected to pass.

[0036] When the traveling units 15A, 15B are traveling with the direction A2 as their travel direction, the detection units 30C, 30D detect objects present on the travel side of the traveling units 15A, 15B in the traveling direction D1. The detection units 30C, 30D are attached to the crane girder 12 on the direction A2 side of the traveling units 15A, 15B. The detection units 30C, 30D detect objects present in detection target areas DEC, DED extending on the travel side (direction A2 side) in the traveling direction D1. The detection target areas DEC, DED are set so that objects present on the traveling paths RDA, RDB within a predetermined distance on the direction A2 side as seen from the traveling units 15A, 15B can be detected where the traveling units 15A, 15B are expected to pass.

[0037] The measurement system 100 for the RTG crane 10 according to this embodiment acquires a reference observation line from the moving object and the container C, and can grasp and correct the inclination of the RTG crane 10 (i.e., the inclination of the detection target area) based on the observation line. FIG. 5 is a schematic plan view for explaining the measurement method of the measurement system 100. While only the detection unit 30D is shown in FIG. 5, similar operations are performed for the other detection units 30A, 30B, and 30C. The measurement system 100 assumes that, for the observation points detected using the detection unit 30D, multiple observation points on the side of the container C are collinear, the horizontal distance between the detection unit 30D and the side of the container C is within a certain range, and the absolute velocity of the container C is zero. As a result, the observation line, which is a straight line connecting the multiple observation points on the side of the container C, can be used as a reference line for grasping the inclination of the RTG crane 10. The measurement system 100 sets two or more container observation point search ranges CSE on one side to match the position of the container C. The measurement system 100 measures the distance and angle to each observation point for each container observation point search range CSE to obtain an observation line, and calculates the angle between the side of the container C and each detection unit 30 to estimate and correct the inclination of the RTG crane 10. The measurement system 100 also assumes that the direction of movement of vehicles such as the transport vehicle 20 is parallel to the container C. As a result, the observation line, which is a straight line connecting multiple observation points on the side of the vehicle, can be used as a reference line for understanding the inclination of the RTG crane 10. The measurement system 100 sets a vehicle observation point search range VSE, measures time-series data of the distance and angle to observation points on the vehicle within the vehicle observation point search range VSE, and estimates the inclination of the RTG crane 10 by calculating the vehicle movement direction and the angle of the detection unit 30D.

[0038] The detection unit 30D is set as the origin, and a moving coordinate system x ｃ -y ｃ Such a coordinate system may be called a global coordinate system. Also, a moving coordinate system x ｃ ´-y ｃ' is set. Such a coordinate system may be referred to as the host vehicle coordinate system. In the following explanation, the RTG crane 10 itself may also be referred to as the "host vehicle". The angle α formed by these two coordinates is the inclination of the RTG crane 10, i.e., the amount of angular deviation in the horizontal direction. Speed ​​data vR of the main body of the RTG crane 10 is acquired by a speed sensor mounted on the main body of the RTG crane 10. In the following explanation, unless otherwise noted, the explanation will be given in the host vehicle coordinate system.

[0039] As shown in FIG. 4, the measurement system 100 detects a distance Y １ The container C located at the position is used to estimate the angle of the RTG crane 10. The measurement system 100 uses the detection unit 30B to measure the distance Y １ The container C located at the position is used to estimate the angle of the RTG crane 10. The measurement system 100 uses the detection unit 30C to measure the distance Y ２ and the distance Y on the right side of the travel direction D1. ３ The measurement system 100 uses the detection unit 30A to estimate the distance Y ２ and the distance Y on the left side of the traveling direction D1. ３ Both of the containers C located at positions 1 and 2 are used to estimate the angle of the RTG crane 10. Note that FIG. 4 is merely an example, and the arrangement of the containers C, etc. is not limited to that shown in FIG.

[0040] Next, with reference to Fig. 7, a block configuration of a crane control system 150 having the measurement system 100 according to this embodiment will be described. Fig. 7 is a block diagram showing the configuration and functions of the crane control system 150 having the measurement system 100 according to this embodiment. As shown in Fig. 7, the crane control system 150 includes a control device 110. The control device 110 receives detection results from the detection unit 30. The control device 110 outputs control signals to the drive unit 50 and the input / output unit 51 of the RTG crane 10. The location where the control device 110 is disposed is not particularly limited, and the control device 110 may be disposed at any position on the RTG crane 10 or at a position remote from the RTG crane 10.

[0041] The drive unit 50 is a device that generates a drive force for moving the spreader 14 along a set conveying path and a device that generates a drive force for moving the traveling units 15A and 15B according to set operations. The drive unit 50 includes, for example, a hoisting device for the spreader 14, a motor for traversing the trolley 13, and a motor for traveling the traveling units 15A and 15B.

[0042] The input / output unit 51 is a device that inputs and outputs various types of information. The input / output unit 51 has, for example, a monitor, a speaker, a warning light, and the like as output devices. The input / output unit 51 has a touch panel, a keyboard, a mouse, and the like as input devices. In this embodiment, the input / output unit 51 may have a touch panel as shown in FIG. 15. FIG. 15 is an example of a setting input screen that allows the user to set the distance of each container lane, etc., as an initial setting. The areas indicated by dashed lines in FIG. 15 are items that the user inputs.

[0043] The control device 110 may be configured as a computer (also referred to as an on-board automatic control PC) including, for example, a processor, a memory, a storage, and a communication interface. The processor is a computing device such as a CPU (Central Processing Unit). The memory is a storage unit such as a ROM (Read Only Memory) or a RAM (Random Access Memory). The storage is a storage unit (storage medium) such as an HDD (Hard Disk Drive). The communication interface is a communication device that realizes data communication. The processor controls the memory, storage, and communication interface, and realizes the functions of the control device 110 described below. The control device 110 realizes various functions by, for example, loading a program stored in the ROM into the RAM and executing the program loaded into the RAM with the CPU. The number of computers constituting the control device 110 may be one or more.

[0044] The control device 110 includes an information processing unit 111 (detection unit, judgment unit), a route setting unit 112, a drive control unit 113, a warning control unit 114, a search unit 115, an observation line setting unit 116, a tilt acquisition unit 117, and a correction unit 118.

[0045] The information processing unit 111 acquires information related to the detection results detected by the detection unit 30, and detects objects within the detection target area DE (see FIG. 4) based on the results. Therefore, the information processing unit 111 also functions as the detection unit 30 that detects objects present on the traveling side of the RTG crane 10 in the traveling direction D1. The information processing unit 111 also performs an abnormality determination to determine whether or not an obstacle exists within the detection target area DE. The route setting unit 112 sets a transfer route for the container C by the spreader 14 of the RTG crane 10.

[0046] The drive control unit 113 controls the drive unit 50 so that the spreader 14 moves according to the conveying path set by the path setting unit 112. The drive control unit 113 also controls the movement of the traveling units 15A and 15B based on the detection results by the detection unit 30. The drive control unit 113 transmits control signals to each device, such as a motor, that constitutes the drive unit 50. As a result, the drive control unit 113 controls the spreader 14 to move according to a predetermined conveying path and controls the traveling units 15A and 15B to perform desired operations. For example, when the drive control unit 113 detects the presence of an object in the detection target area DE of the detection unit 30, it stops the traveling of the traveling units 15A and 15B.

[0047] When it is necessary to perform safety response processing, the warning control unit 114 issues a warning to the user by controlling the input / output unit 51. For example, when the detection unit 30 detects that an object exists in the detection target area DE, the warning control unit 114 issues a warning.

[0048] The search unit 115 searches for observation points within the search range using the detection unit 30. The search unit 115 sets multiple search ranges on one side in the travel direction of the RTG crane 1. In this embodiment, the search unit 115 sets a vehicle observation point search range VSE and a container observation point search range. Furthermore, the search unit 115 sets multiple container observation search ranges for multiple rows of container lanes. The search unit 115 searches for observation points on the sides of containers C within the container observation point search range CSE. The search unit 115 also searches for vehicle observation points within the vehicle observation point search range VSE. Note that an observation point is a point whose distance from the detection unit 30 and its angle with the detection unit 30 in the horizontal direction are detected by the detection unit 30, and whose reflected signal intensity from that point is equal to or greater than a threshold.

[0049] 5 and 6, the container observation point search range CSE and vehicle observation point search range VSE set by the search unit 115 will be described. Note that the search range set for the detection unit 30 may be set such that the container yard is on the left side, the right side, or both sides as viewed from the legs of the RTG crane. Also, the distance Y between the xc axis and the container yard CS1 is １The spacing between containers C and the containers C varies depending on the usage environment. Therefore, the search unit 115 sets the placement of the container observation point search range CSE and the vehicle observation point search range VSE to be suitable for the usage environment.

[0050] As shown in Fig. 5, the search unit 115 sets, as the container observation point search range CSE, a first container observation point search range CSE1 for searching for the containers C in the first row, a second container observation point search range CSE2 for searching for the containers C in the second row, and an Nth container observation point search range CSEN for searching for the containers C in the Nth row (N ≥ 2). Here, as shown in Fig. 5, the search unit 115 sets a preset value x ａ１ , y ａ１ Using "travel direction D1:x ａ１ × Width direction D2: y ａ１ " is the first container observation point search range, and the preset value x ａ２ , y ａ２ Using "travel direction D1:x ａ２ × Width direction D2:y ａ２ " is the second container observation point search range.

[0051] The size of the container observation point search range CSE is set so that observation points of the container lane being searched can be detected regardless of the inclination of the RTG crane 1, while not detecting observation points of other container lanes. In Figure 6, a first container observation point search range CSE1 is set for the first container lane CL1, a second container observation point search range CSE2 is set for the second container lane CL2, and a third container observation point search range CSE3 is set for the third container lane CL3. The container observation point search ranges CSE1, CSE2, and CSE3 indicated by dashed-dotted lines indicate the state in which they are most inclined toward the vehicle travel path VR1. The container observation point search ranges CSE1, CSE2, and CSE3 indicated by dashed-dotted lines indicate the state in which they are most inclined away from the vehicle travel path VR1. The side of the container C facing the vehicle travel path VR1 is located near the boundary of the container lane CL on the vehicle travel path VR1 side. Therefore, regardless of the state of inclination, the container observation point search range CSE is set to include the boundary of the target container lane CL on the vehicle travel path VR1 side, but not to include the boundary of other container lanes CL on the vehicle travel path VR1 side. Note that it is assumed that the inclination of the RTG crane 1 is within a certain range.

[0052] As shown in FIG. 5, the search unit 115 uses the preset values ​​xb and yb to find the "traveling direction D1:x ｂ × Width direction D2: y ｂ " is set as the vehicle observation point search range VSE. Note that the search unit 115 may set multiple ranges as the vehicle observation point search range VSE using multiple values ​​set in advance. In the example of Figure 5, the vehicle observation point search range VSE is set on the left and right of the x'c axis. In the following figures, only the container observation point search range CSE and vehicle observation point search range VSE necessary for explanation will be shown.

[0053] The search unit 115 can observe multiple observation points detected by the detection unit 30 in time series. That is, when searching for vehicle observation points within the vehicle observation point search range VSE, the search unit 115 observes the observation points in time series. The search unit 115 can simultaneously observe multiple observation points from the same object or multiple objects lined up in a row detected by the detection unit 30. Details will be described later.

[0054] Returning to FIG. 7 , the observation line setting unit 116 sets an observation line based on multiple observation points observed by the search unit 115. When multiple vehicle observation points are observed within the vehicle observation point search range VSE, the observation line setting unit 116 sets an observation line by setting a straight line between the multiple observation points. When multiple container C observation points are observed within the container observation point search range CSE, the observation line setting unit 116 sets an observation line by setting a straight line between the multiple observation points. When two observation points are observed by the search unit 115, the observation line setting unit 116 sets an observation line by setting a straight line connecting the two observation points. When three or more observation points are observed by the search unit 115, the observation line setting unit 116 sets an approximation line based on the three or more observation points. The observation line setting unit 116 also obtains the residual between the observation points and the approximation line and excludes observation points whose residual is greater than a threshold. In this case, the observation line setting unit 116 sets the observation line again using the excluded observation points.

[0055] The tilt acquisition unit 117 acquires the amount of tilt of the RTG crane 1 with respect to the travel path RD based on the observation line. The tilt acquisition unit 117 may acquire the amount of tilt of the RTG crane 1 by calculating the angle between the observation line and the axes of the coordinate system set in the detection unit 30. Specific examples of methods for acquiring the amount of tilt will be described later.

[0056] The correction unit 118 corrects the tilt of the RTG crane 10 based on the amount of tilt of the RTG crane 10 acquired by the tilt acquisition unit 117 (see FIG. 4). "Correction" of the tilt of the RTG crane 10 means, for example, at least one of correcting the direction of travel of the RTG crane 10 or correcting the detection target area DE of the detection unit 30.

[0057] Next, the processing content of the measurement system 100 will be described with reference to Figures 8 and 9. Figures 8 and 9 are flowcharts showing the processing content of the measurement system 100. Figures 8 and 9 explain an example in which a millimeter-wave radar is used as the detection unit 30. As shown in Figure 8, first, the search unit 115 sets a vehicle observation point search range VSE and a container observation point search range CSE (see Figure 5) (step S10). Note that the search unit 115 may set the vehicle observation point search range VSE and the container observation point search range CSE and perform the following processing only when it receives a signal from the RTG crane 10 indicating that loading and unloading of the container C onto the vehicle has been completed.

[0058] Next, the measurement system 100 performs "Loop 1" processing to acquire the angular deviation of the host vehicle based on the vehicle observation points (steps S20 to S70). "Loop 1" processing is repeatedly executed until processing is completed for all vehicle observation point search ranges VSE. The search unit 115 determines whether an object is present within the vehicle observation point search range VSE (step S30). If it is determined in step S30 that an object is not present, the first loop 1 is terminated (step S70). If another vehicle observation point search range VSE exists, loop 1 processing is performed again for the other vehicle observation point search range VSE. Once processing is completed for all vehicle observation point search ranges VSE, loop 1 is completed and the process proceeds to FIG. 9.

[0059] On the other hand, if it is determined in step S30 that an object exists, the measurement system 100 tracks the object and acquires an observation line from the object (step S40). The measurement system 100 determines whether the tracked object is a vehicle (step S45). If it is determined in step S45 that the tracked object is not a vehicle, the first loop 1 ends (step S70). If it is determined in step S45 that the tracked object is a vehicle, the process proceeds to step S50, which will be described later.

[0060] Specifically, as shown in FIG. 10 , the search unit 115 searches the vehicle observation point search range VSE at intervals of Δt seconds using the millimeter-wave radar of the detection unit 30D. The vehicle 60 shown with a two-dot chain line in the figure indicates its position at "time t - Δt." The vehicle 60 shown with a solid line in the figure indicates its position at "time t," which is the current time. The search unit 115 acquires and stores data on the distance L, angle Θ, and intensity I of each point at the current time t. The search unit 115 calculates and stores the coordinates (x, y) of each observation point on the moving coordinate system using "y = L sin Θ" and "x = L cos Θ." FIG. 10 shows observation point VP1 of the vehicle 60 at the current time "time t," and observation point VP2 of the vehicle 60 at "time t - Δt." The search unit 115 retains points that satisfy the following "Condition A" and "Condition B" as observation points. If "Condition B" is satisfied, the measurement system 100 determines that an object exists within the vehicle observation point search range (step S30). If "Condition A" is satisfied, the measurement system 100 determines that the tracked object is a vehicle (step S45).

[0061] [Condition A] The search unit 115 searches for the observation point VP1 (x ｔ , y ｔ ) and the observation point VP2 (x ｔ－Δｔ , y ｔ－Δｔ ) to calculate the absolute velocity (v ｘｃ ',v ｙｃ The search unit 115 calculates the threshold value (v ｘ１ ,v ｙ１ ) to "v ｘｃ '≧=v ｘ , v ｙｃ '≦v ｙ１ " are retained as observation points.

[0062] [Condition B] The search unit 115 determines whether the intensity I at the point is greater than or equal to the threshold I Ｔ Points where this is the case or higher are left as observation points.

[0063] Here, when the moving measurement object is the side of the vehicle 60 and the vehicle 60 moves straight in the traveling direction D1, the observation points VP1 and VP2 are on the same straight line. Therefore, the observation line setting unit 116 takes an absolute coordinate system based on the coordinates at time t, and calculates the observation point VP1 (x ｔ ,y ｔ ) and the observation point VP2 (x ｔ－Δｔ , y ｔ－Δｔ ) is drawn. The observation line setting unit 116 sets this line as the observation line VL. The equation for the observation line VL can be expressed as "Y = aX + b" using coefficients a and b. ｔ ,y ｔ ) and the observation point VP2 (x ｔ－Δｔ , y ｔ－Δｔ ) to calculate the slope a of the observation line VL, it is expressed by equation (3). Note that the observation line can also be calculated by using the least squares method or the like to calculate an approximate straight line from observation points obtained at three or more times, taking into account measurement noise and the like.

[0064] If it is determined in step S45 that the tracked object is a vehicle, the tilt acquisition unit 117 calculates the angle φ between the observation line VL obtained in step S40 and the y-axis (step S50). If multiple observation lines VL are obtained, the tilt acquisition unit 117 calculates φ for each observation line VL and takes the average. φ is calculated as follows: "φ=90°-tan －１ a". Because the obtained value of φ indicates that the coordinate system has rotated, the tilt acquisition unit 117 can calculate the angular deviation α of RTG1 as "α = φ - 90°" (step S60). Once step S60 is completed, the first loop 1 ends (step S70). If other vehicle observation point search ranges VSE exist, loop 1 processing is performed again for the other vehicle observation point search ranges VSE. Once processing for all vehicle observation point search ranges VSE has been completed, loop 1 ends and the process moves to Figure 9. Note that the order in which processing is performed for multiple vehicle observation point search ranges VSE is not limited, and processing for multiple observation point search ranges VSE may be performed simultaneously in parallel.

[0065] Next, the measurement system 100 performs "loop 2" processing to acquire the angular deviation amount of the host vehicle based on the observation points of the container C (steps S100 to S230). The "loop 2" processing is repeatedly executed until processing is completed for all container observation point search ranges CSE. The search unit 115 searches within the container observation point search range CSE (step S110). The search unit 115 simultaneously observes multiple observation points from the same container C.

[0066] The search unit 115 searches the container observation point search range CSE for each container observation point search range CSE using the millimeter wave radar of the detection unit 30, and leaves as observation points points that satisfy the following conditions "Condition C" and "Condition D" (step S120). ｉ , angle θ ｉ Get the data.

[0067] [Condition C] When the object to be measured for angle is a container C, the container C is stationary and therefore its absolute velocity is 0. Therefore, the search unit 115 calculates the velocity v at each point by the millimeter wave radar. ｉ ' and the absolute velocity (v ｘｃｉ ',v ｙｃｉ ') and "v ｘｃｉ '=v i 'cosθ ｉ +v Ｒ = 0", "v ｙｃｉ '=v ｉ 'sinθ ｉ The points where "=0" are left as observation points.

[0068] [Condition D] The search unit 115 determines whether the intensity I at the point is greater than or equal to the threshold I Ｓ Points where this is the case or higher are left as observation points.

[0069] Next, the search unit 115 calculates the coordinates (x i ,y i ) (step S130). i =l i sinθ ｉ "," "x ｉ =l ｉ cosθ ｉIn the example shown in FIG. １ and angle θ １ The observation point CP1 and the distance l ２ and angle θ ２ Since the observation point CP2 has been acquired, the search unit 115 obtains the coordinates (x １ ,y １ ), (x ２ ,y ２ ) is calculated.

[0070] Here, the search unit 115 determines whether two or more observation points have been acquired (step S140). If the result in step S140 is "NO," i.e., if there is one or zero observation points, the search unit 115 determines whether there was only one observation point acquired (step S150). If the result in step S150 is "YES," i.e., if there is one observation point, the process returns to step S110, and the process is repeated until there are two or more observation points. On the other hand, if the result in step S150 is "NO," i.e., if there are zero observation points and it can be determined that the angle measurement object does not exist in the container observation point search range CSE, the first loop 2 ends (step S230), and an observation point in the next container observation point search range is acquired. Once processing for all container observation point search ranges CSE has been completed, loop 2 ends and processing proceeds to the next step. Note that the order of processing for multiple container observation point search ranges CSE is not limited, and processing for multiple observation point search ranges CSE may be performed simultaneously in parallel.

[0071] If step S140 returns "YES," the search unit 115 determines whether there were two observation points (step S160). If step S160 returns "YES," i.e., if there were two observation points, the observation line setting unit 116 draws a straight line passing through the two observation points (step S170). The observation line setting unit 116 considers this straight line to be the complete observation line VL (step S200). As shown in FIG. 11, the observation line setting unit 116 draws a straight line connecting observation point CP1 and observation point CP2. The observation line setting unit 116 sets this straight line as the observation line VL. The equation for the observation line is expressed as "y = ax + b" using coefficients a and b.

[0072] If step S160 returns "NO," i.e., if there are three or more observation points, the observation line setting unit 116 draws an approximate line to the multiple observation points (step S180). When the object to be measured for angle is the side of container C, the surface is flat, so the observation points are on the same line (see, for example, FIG. 12). Therefore, the observation line setting unit 116 draws a line passing through all the observation points. The observation line setting unit 116 sets this line as the observation line VL. The equation for the observation line VL is expressed as "y = ax + b" using coefficients a and b. Here, the observation line setting unit 116 calculates an approximate line for all the observation points using the least squares method or the like, taking into account measurement noise, and sets this approximate line as the observation line VL.

[0073] Next, the observation line setting unit 116 calculates the residual ε i Here, the observation line setting unit 116 calculates the threshold value ε a and the residuals ε i The absolute value of ε a It is then determined whether the difference is within the range (step S190). If the determination in step S190 is "YES," the observation line setting unit 116 determines that the observation line VL is complete using the calculated approximation line (step S200). Once the observation line VL is complete, loop 2 ends. For example, in the example shown in FIG. 12, the observation line setting unit 116 draws approximation lines for the three observation points CP1, CP2, and CP3. The residual error ε for all of the observation points CP1, CP2, and CP3 is i The absolute value of ε a If it is within the range, the approximation line is completed as the observation line VL.

[0074] On the other hand, if the determination in step S190 is "NO," that is, if the observation line setting unit 116 determines that the residual error ε i The absolute value of ε aIf the residual error is larger than 0.05, the observation point is likely to have detected a response from an obstacle other than container C at container yard CS1, such as another vehicle, and therefore the observation point is excluded. Specifically, as shown in Figure 13, when observation point CP3 detects a response from obstacle 70, observation point CP3 is located at a position that is off the side of container C. In this case, the residual error for observation point CP3 is large, so the observation line setting unit 116 excludes observation point CP3.

[0075] If at least one observation point has been excluded, the observation line setting unit 116 determines whether two observation points remain (step S210). If the determination in step S210 is "YES," that is, if there are two observation points remaining, the observation line setting unit 116 performs the aforementioned step S170 and draws a line passing through the two observation points. For example, in the example of Figure 13, the observation line setting unit 116 draws a line passing through the remaining observation points CP1 and CP2, and designates this line as the observation line VL.

[0076] If step S210 returns "NO," i.e., if the number of remaining observation points is three or more or one or less, observation line setting unit 116 determines whether there are three or more observation points (step S220). If step S220 returns "YES," i.e., if there are three or more remaining observation points, the process is repeated again from step S180. On the other hand, if step S220 returns "NO," i.e., if there is one or less remaining observation point, the process is repeated again from step S110.

[0077] When the processing of Loop 2 for a certain container observation point search range CSE is completed, if there is another container observation point search range CSE, the processing of Loop 2 is repeated again from step S100 for that container observation point search range CSE. For example, in the example shown in Figure 14, when the processing of Loop 2 for container observation point search range CSE1 is completed, Loop 2 is repeated for container observation point search range CSE2.

[0078] When loop 2 processing has been completed for all container observation point search ranges CSE, the tilt acquisition unit 117 determines the angle φ between the observation line VL obtained in loop 2 processing and the y-axis (step S240). In step S240, the same processing as in step S50 is performed. The tilt acquisition unit 117 calculates the angle deviation α of the RTG 1 (step S260). In step S260, the same processing as in step S60 is performed. When observation lines are obtained from two or more container observation point search ranges, the tilt acquisition unit 117 may calculate the angle deviation α as the average of the obtained values, may calculate a weighted average, or may adopt the most reliable value.

[0079] Next, the correction unit 118 corrects the detection target area DE of the detection unit 30 by the acquired angular deviation amount α (step S260). Note that if the angular deviation amount α is obtained in both the processing of step S60 of loop 1 and the processing of step S250 of loop 2, the average of the obtained values ​​may be used, a weighted average may be calculated, or the most reliable value may be used. Furthermore, if different angular deviation amounts α are obtained from multiple detection units 30, for example, the variation in the angular deviation amounts α obtained from these sensors may be calculated, and if the variation is below a threshold, the traveling direction may be corrected. If the variation is above the threshold, the detection target area DE of the detection unit 30 that output the outlier may be corrected. Upon completion of step S260, the processing shown in FIGS. 8 and 9 ends, and similar processing is repeated again at a predetermined timing. Note that the order of the processing of loop 1 and the processing of loop 2 is not limited. The processing of loop 1 may be performed after the processing of loop 2, or the processing of loop 1 and loop 2 may be performed simultaneously in parallel.

[0080] Next, a specific example of calculation will be described using the case where the measurement environment is as shown in Figs. 10 and 14. １ The width of the road RDB is "y １ ", and the width of the vehicle road VR1 is "y ２ = y ３ "

[0081] The search unit 115 sets a container observation point search range CSE and a vehicle observation point search range VSE.ａ１ "," "y ａ１ " is used to write "x ｃ ' and 'y ｃ The predetermined range of "x'" is set as the first container observation point search range CSE1. a２ "," "y ａ２ " is used to write "x ｃ ', "y ｃ The predetermined range of "x'" is set as the second container observation point search range CSE2. ａ３ "," "y ａ３ " is used to write "x ｃ ', "y ｃ The predetermined range of "x'" is set as the third container observation point search range CSE3. The fourth container observation point search range and subsequent ranges are set in the same manner. ｂ "," "y ｂ " is used to write "x ｃ ', "y ｃ ', 'y ｃ The predetermined range of "v" in the xc'-axis direction is defined as the vehicle observation point search range VSE. Also, "t = 0 s" and "Δt = 1 s" are defined. The speed of the RTG crane 10 is "v" in the xc'-axis direction. Ｒ "

[0082] (I) Angle Estimation by Searching for Vehicle Observation Points Observation line VL is acquired from an observation point within the vehicle observation point search range VSE. As shown in FIG. 10, the search unit 115 detects an observation point within the vehicle observation point search range VSE and measures its movement as follows: Time 0 s: (L ｔ ,Θt) Time-1s: (L ｔ－１ , Θ ｔ－１ )

[0083] For data acquired at the observation point, coordinates on the moving coordinate system (x ｉ ,y ｉ ) is calculated as follows: Time 0 s; (x ｔ ,y ｔ ) Time-1s: (x ｔ－１ ,y ｔ－１ )

[0084] From this, the absolute velocity in the direction of the vehicle's coordinate system (v ｘｃ′ ,v ｙｃ′) is calculated. Therefore, using the threshold value "vx1 = vy1", ｘｃ '≧v ｘ１ ,v ｙｃ '≦v ｙ１ ". The intensity I at each point is calculated based on the threshold I ｓ The observation line setting unit 116 calculates the observation line from these observation points. An absolute coordinate system is set based on the coordinates at time 0 s, and the coordinates at each point are calculated. Time 0 s: (x ｔ ,y ｔ ) Time-1s: (x ｔ－１ , y ｔ－１ )

[0085] The observation line setting unit 116 determines the equation of the observation line VL. From the coordinates of the observation point at each time, the equation of the observation line VL is expressed as "y = ax + b" using coefficients a and b.

[0086] The tilt acquisition unit 117 obtains the angle φ between the observation line VL and the y-axis. From the above, the angle deviation amount α of the RTG crane 10 can be estimated.

[0087] [(II) Angle Estimation by Searching for Container Observation Points] The measurement system 100 acquires an observation line VL from an observation point within each container observation point search range CSE. An example of the first container observation point search range CSE1 will be described below. As shown in FIG. 14 , within the first container observation point search range CSE1, the distance l to the measurement object is ｉ , angle θ ｉ The data of the three observation points are acquired only at points where the absolute velocity is 0 and the intensity is equal to or greater than the threshold as follows: Observation point CP1: (l １ , θ １ ) Observation point CP2: (l ２ , θ ２ ) Observation point CP3: (l ３ , θ ３ )

[0088] For the data acquired at each observation point, the coordinates of each observation point on the moving coordinate system (x ｉ ,y ｉ ) is calculated as follows: Observation point CP1: (x １ , y １ ) Observation point CP2: (x ２ , y２ ) Observation point CP3: (x ３ , y ３ )

[0089] The observation line setting unit 116 determines the VL equation for the observation line. From the observation points CP1 to CP3, the equation for the observation line VL is expressed as "y = ax + b" using coefficients a and b. In addition, at this time, the residual ε ｉ Regarding the threshold value "ε ａ ” at all observation points, ｉ = 0 < ε ａ "

[0090] The tilt acquisition unit 117 obtains the angle φ between the observation line VL and the y-axis. From the above, the angle deviation amount α of the RTG crane 10 is estimated.

[0091] The measurement system 100 acquires the observation line VL in the second container observation point search range CSE2, the third container observation point search range CSE3, etc., and calculates the angular deviation amount α of the RTG crane 10. As a result, it is assumed that a certain value is acquired as "α" in the second container observation point search range CSE2. It is assumed that the observation line VL cannot be acquired from the third container observation point search range CSE3 onwards. The tilt acquisition unit 117 acquires the value of "α" by averaging all the angular deviation amounts α.

[0092] The tilt acquisition unit 117 calculates the average of the values ​​of the angle deviation amount α obtained in the above processes (I) and (II) and acquires the angle deviation amount α of the detection unit 30D. The tilt acquisition unit 117 similarly acquires the angle deviation amount α of the detection units 30A, 30B, and 30C. The correction unit 118 determines the variation in the angle deviation amount α of the RTG crane 10 obtained from the detection units 30A, 30B, 30C, and 30D, and corrects the traveling direction if the variation is below a threshold, or corrects the detection target area DE of the detection unit 30 that output the outlier if the variation is above the threshold.

[0093] Next, the functions and effects of the RTG crane 10, measurement system 100, and measurement method according to this embodiment will be described.

[0094] The RTG crane 10 includes a search unit 115 that searches for observation points within a search range using the detection unit 30, and an observation line setting unit 116 that sets an observation line VL based on multiple observation points observed by the search unit 115. If an object (e.g., the side of a container C) with a surface parallel to the traveling direction D1 of the RTG crane 10 is present around the travel path of the RTG crane 10, the search unit 115 sets the search range to search for the observation point of the object. The observation line VL set based on the observation points thus obtained can be used as a reference line for determining the inclination if the traveling direction or search range of the RTG crane 10 is inclined relative to the travel path. Therefore, by setting an observation line based on multiple observation points observed by the search unit 115, the observation line setting unit 116 can use the observation line as a reference line for determining the inclination. Therefore, the inclination acquisition unit 117 can accurately acquire the inclination of the RTG crane 10 relative to the travel path based on the observation line VL. Furthermore, the inclination of the RTG crane 10 can be easily determined simply by searching for observation points and setting the observation line VL, without the need to install guide lines on the travel path. Therefore, by correcting the inclination, the accuracy of object position detection by the detector 30 can be improved. As a result, the accuracy of object position detection can be easily improved.

[0095] The searching unit 115 may set multiple search ranges on one side in the traveling direction D1 of the RTG crane 10. In this case, when multiple rows of containers C exist near the traveling path, the searching unit 115 can set a search range for each row of containers C, or when containers C and vehicles exist, can set a search range for each object. In this way, by setting the observation line VL using the search results for multiple objects, the inclination of the RTG crane 10 can be grasped more accurately.

[0096] The search unit 115 observes multiple observation points in time series, and if it determines that the object is moving, the observation line setting unit acquires an observation line based on the observation points. If the search unit 115 observes three or more observation points in time series, the observation line setting unit 116 calculates an approximation line based on those observation points and uses this as the observation line. If the search unit 115 observes two observation points in time series, the observation line setting unit 116 connects those observation points to create an observation line. If the search unit observes one or fewer observation points in time series, the observation line setting unit 116 may command the observation to be redone. In this case, the search unit can set an observation line based on the moving object from the results of observing multiple observation points in time series.

[0097] The search unit 115 simultaneously observes multiple observation points from the same object or from multiple objects arranged in a row, and obtains an observation line based on the observation points. If the search unit observes three or more observation points, the observation line setting unit 116 calculates an approximate line based on those observation points and uses this as the observation line. If the search unit 115 observes two observation points, the observation line setting unit 116 connects those observation points to create an observation line. If the search unit 115 observes one or less observation points, the observation line setting unit 116 may command the observation to be redone. In this case, the search unit 115 can set an observation line for a stationary container based on the results of simultaneously observing multiple observation points.

[0098] If three or more observation points are observed by the search unit 115, the observation line setting unit 116 may set an approximation line based on the three or more observation points. This allows the observation line setting unit 116 to set the observation line VL with high accuracy even if it is not possible to connect the observation points with a straight line.

[0099] The observation line setting unit 116 may obtain the residual between the observation point and the approximation line and exclude observation points for which the residual is greater than a threshold. For example, if an observation point corresponding to an obstacle has occurred, the observation line setting unit 116 can exclude the observation point corresponding to such an obstacle.

[0100] The measurement system 100 of this embodiment is a measurement system 100 that measures the positional relationship of an object located on the traveling side in the traveling direction of an RTG crane 10 traveling on a traveling path, and is equipped with a detection unit 30 that detects the distance and angle to the object, a search unit 115 that searches for observation points within the search range using the detection unit 30, an observation line setting unit 116 that sets an observation line VL based on multiple observation points observed by the search unit 115, and an inclination acquisition unit 117 that acquires the inclination of the RTG crane 10 with respect to the traveling path based on the observation line VL.

[0101] A measurement method according to one example of this embodiment is a measurement method for measuring the positional relationship of an object present on the traveling side in the traveling direction of an RTG crane 10 traveling on a traveling path, and includes a detection process (S30, S40, S110, etc.) for detecting the distance and angle to the object, a search process (S40, S110, etc.) for searching for observation points within a search range using the detection process, an observation line setting process (S170, S200, etc.) for setting an observation line VL based on multiple observation points observed in the search process, and an inclination acquisition process (S60, S250, etc.) for acquiring the inclination of the RTG crane 10 relative to the traveling path based on the observation line VL.

[0102] According to this measurement system and measurement method, it is possible to obtain the same functions and effects as those of the RTG crane described above.

[0103] The present disclosure is not limited to the above-described embodiments.

[0104] For example, in the above embodiment, a vehicle observation point search range and a container observation point search range are set, but it is sufficient to set at least one of them. Also, although multiple container observation point search ranges are set for multiple rows of container lanes, they may be set for only one row of container lane.

[0105] For example, the environment around the RTG crane illustrated in the above embodiment is merely an example and may be changed as appropriate.

[0106] 10...RTG crane, 30...detection unit, 100...measurement system, 115...search unit, 116...observation line setting unit, 117...tilt acquisition unit.

Claims

1. An RTG crane that travels on a travel path, comprising: a detection unit that detects the distance and angle between the RTG crane and an object on the traveling side in the direction of travel; a search unit that uses the detection unit to search for observation points within a search range; an observation line setting unit that sets an observation line based on the multiple observation points observed by the search unit; and an inclination acquisition unit that acquires the inclination of the RTG crane with respect to the travel path based on the observation line.

2. An RTG crane as described in claim 1, wherein the search unit sets a plurality of search ranges on one side in the travel direction of the RTG crane.

3. The RTG crane described in claim 1, wherein the search unit observes multiple observation points in time series, and if the object is determined to be a moving object, the observation line setting unit obtains the observation line based on the observation points, and if the search unit observes three or more observation points in time series, the observation line setting unit calculates an approximate line based on those observation points and uses this as the observation line, and if the search unit observes two observation points in time series, the observation line setting unit connects those observation points to use this as the observation line, and if the search unit observes one or less observation points in time series, the observation line setting unit commands the observation to be repeated.

4. The RTG crane described in claim 1, wherein the search unit simultaneously observes multiple observation points from the same object or from multiple objects arranged in a row, and obtains the observation line based on the observation points; if the search unit observes three or more observation points, the observation line setting unit calculates an approximate line based on those observation points and uses this as the observation line; if the search unit observes two observation points, the observation line setting unit connects those observation points to use this as the observation line; and if the search unit observes one or fewer observation points, the observation line setting unit commands the observation to be repeated.

5. An RTG crane as described in claim 4, wherein the observation line setting unit obtains the residual between the observation point and the approximation line, and excludes the observation point where the residual is greater than a threshold value.

6. A measurement system that measures the positional relationship of an object on the traveling side of an RTG crane traveling on a travel path in the direction of travel, comprising: a detection unit that detects the distance and angle to the object; a search unit that searches for observation points within a search range using the detection unit; an observation line setting unit that sets an observation line based on the multiple observation points observed by the search unit; and an inclination acquisition unit that acquires the inclination of the RTG crane with respect to the travel path based on the observation line.

7. A measurement method for measuring the positional relationship of an object present on the traveling side in the traveling direction of an RTG crane traveling on a traveling path, comprising: a detection process for detecting the distance and angle to the object; a search process for searching for observation points within a search range using the detection process; an observation line setting process for setting an observation line based on the multiple observation points observed in the search process; and an inclination acquisition process for acquiring the inclination of the RTG crane with respect to the traveling path based on the observation line.

Images