Cushioning material detection device and cushioning material detection method

Abstract

To suitably detect a cushioning material at a position where loads are stacked one on top of another.SOLUTION: A cushioning material detection device comprises an identification unit 24 and a determination unit 25. The identification unit 24 identifies a measurement region Pm at which a plurality of rays of reflected light of a plurality of lasers La with which the measurement region Pm of a coil C is irradiated from mutually different irradiation directions and respectively having been reflected in each irradiation direction are received at prescribed signal strength. The prescribed signal strength corresponds to the signal reflection rate of a retroreflection material in a marker part 150 on the surface of a cushioning material 140 which is located on the coil C on a floor surface 100. The determination unit 25 determines the cushioning material 140 present at a position on the floor surface 100 where the coil C should be disposed, on the basis of the measurement region Pm identified by the identification unit 24.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a cushioning material detection device and a cushioning material detection method. [Background technology]

[0002] In some cases, coils of plate materials such as steel sheets are stacked for storage. In order to prevent damage to the stacked loads due to contact between the loads, it is known to place cushioning materials between the upper and lower loads (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-298485 A Summary of the Invention [Problem to be solved by the invention]

[0004] When stacking loads using a lifting machine such as a crane, it is important to correctly place cushioning materials at the positions where the loads are stacked in order to avoid damage to the stacked loads. An object of the present disclosure is to appropriately detect cushioning materials at the positions where the loads are stacked. [Means for solving the problem]

[0005] A cushioning material detection device according to the present disclosure includes an identification unit and a discrimination unit. The identification unit identifies a measurement site where a plurality of reflected signals, which are respectively reflected in each irradiation direction of a plurality of measurement signals irradiated from different irradiation directions to a measurement site of a load on a floor where a load suspended by a lifting machine is stacked, are received with a predetermined signal strength. The predetermined signal strength corresponds to the signal reflectance of a retroreflective material in a marker portion on the surface of the cushioning material placed on the load on the floor. The discrimination unit discriminates the cushioning material present at a position on the floor where the load should be placed, based on the measurement site identified by the identification unit.

[0006] In the cushioning material detection device according to the present disclosure, the measurement site may include a plurality of irradiation points to which the measurement signals are respectively irradiated. When the measurement site includes a plurality of irradiation points, the identification unit may accumulate signal intensities in the irradiation directions of the reflected signals reflected at the plurality of irradiation points. Based on the accumulated signal intensities, the identification unit can identify the measurement site at which the reflected signals reflected in each irradiation direction are received with a predetermined signal intensity.

[0007] In the cushioning material detection device according to the present disclosure, the identification unit may group and store information on the signal strength of reflected signals reflected at a plurality of irradiation points included in one measurement site, or may store the information linked to the measurement site including the plurality of irradiation points. When the identification unit groups and stores information on the signal strength of reflected signals, or stores the information linked to the measurement site, the identification unit can identify a measurement site where a plurality of reflected signals within the measurement site reflected in each irradiation direction are received at the predetermined signal strength from the stored signal strength information.

[0008] The cushioning material detection device according to the present disclosure includes an identification unit and a discrimination unit. The identification unit identifies a measurement site where a reflected signal reflected in the direction of irradiation of a measurement signal, which is irradiated to a measurement site of a load on a floor where a coil-shaped load suspended by a lifting machine is stacked, is received with a predetermined signal strength. The predetermined signal strength corresponds to the signal reflectance of an anti-reflection material in a marker portion on the surface of the cushioning material placed on the load on the floor. The discrimination unit discriminates the cushioning material present at a position on the floor where the load should be placed, based on the measurement site identified by the identification unit.

[0009] In the cushioning material detection device of the present disclosure, the identification unit may identify a measurement location where a reflected signal corresponding to a measurement signal irradiated to the measurement location from a direction where the angle with respect to a perpendicular to the surface of the load on the floor is within a predetermined angle range is received with a predetermined signal strength.

[0010] The cushioning material detection device according to the present disclosure may further include an acquisition unit that acquires position information of a load on a floor. When the cushioning material detection device further includes the acquisition unit, the identification unit may identify a measurement portion where a reflected signal is received with a predetermined signal strength within a detection range set based on the position information.

[0011] In the cushioning material detection device according to the present disclosure, the identification unit may identify a measurement portion where a reflected signal of a measurement signal that has passed through the same area is received with a predetermined signal strength among a plurality of areas obtained by dividing a plane parallel to a floor surface on which a load is placed on the floor in the movement direction of the lifting machine. In this case, the discrimination unit may discriminate a cushioning material that is present at a position on the floor where the load should be placed, based on the area identified as the measurement portion where the reflected signal is received with the predetermined signal strength.

[0012] In the cushioning detection device of the present disclosure, the discrimination unit may discriminate cushioning material present at a position on the floor where the load should be placed, based on the size of a group of areas in the direction of movement that are connected to an area identified as a measurement portion where a reflected signal is received at a predetermined signal strength.

[0013] In the cushioning material detection device according to the present disclosure, the load may have a cylindrical or columnar outer shape, and the measurement signal may be irradiated to the same measurement location while changing the position at least in the circumferential direction of the load.

[0014] The cushioning material detection method according to the present disclosure can be performed using a computer having a calculation unit and an input / output unit. The calculation unit identifies a measurement site where a plurality of reflected signals, which are respectively reflected in each irradiation direction of a plurality of measurement signals irradiated from different irradiation directions to a measurement site of a load on a floor on which a load suspended by a lifting machine is stacked, are received with a predetermined signal strength. The predetermined signal strength corresponds to the signal reflectance of the retroreflective material in the marker portion on the surface of the cushioning material placed on the load on the floor. The calculation unit identifies the cushioning material present at the position on the floor where the load should be placed based on the identified measurement site.

[0015] The cushioning material detection method according to the present disclosure can be performed using a computer having a calculation unit and an input / output unit. The calculation unit identifies a measurement site where a measurement signal is irradiated from a direction directly facing the load on the floor, and a reflected signal reflected in the direction of irradiation of the measurement signal is received with a predetermined signal strength at a measurement site of the load on the floor on which the load suspended by the lifting machine is stacked. The predetermined signal strength corresponds to the signal reflectance of an anti-reflective material in a marker portion on the surface of the cushioning material to be placed on the load on the floor. The calculation unit identifies the cushioning material present at the position on the floor where the load should be placed, based on the identified measurement site. Effect of the Invention

[0016] According to the present disclosure, it is possible to preferably detect the cushioning material at the position where the load is stacked. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a diagram illustrating a conveying device including a cushioning material detection device according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a block diagram showing a schematic configuration of a control system of the transport device including the cushioning material detection device of FIG. [Diagram 3] FIG. 3 is a diagram showing the coil of FIG. [Figure 4] FIG. 4 is a diagram showing an example of the arrangement of a plurality of coils on the premises of a building. [Diagram 5] FIG. 5 is a diagram showing a cushioning material that is placed between upper and lower coils when the coils of FIG. 1 are stacked. [Figure 6] FIG. 6 is a diagram showing a state in which the cushioning material of FIG. 5 is placed on the coil on the floor of FIG. [Figure 7] FIG. 7 is a diagram showing scanning positions of the coil on the floor by the lasers of the first and second sensors in FIG. [Figure 8] FIG. 8 is a diagram showing coils to be transported or to be subjected to position estimation in the carrying-out step. [Figure 9] FIG. 9 is a diagram showing coils to be transported or to be subjected to position estimation in the carry-in process. [Figure 10] FIG. 10 is a flowchart of the transport process. [Figure 11] FIG. 11 is a flowchart of the measurement movement process. [Figure 12] FIG. 12 is a diagram for explaining the basic operation of the measurement movement in the measurement process. [Figure 13] FIG. 13 is a diagram illustrating a case where the first sensor and the second sensor use a laser to scan a marker portion made of a retroreflective material of a cushioning material arranged on the circumferential surface of a coil. [Figure 14] FIG. 14 is a diagram illustrating a case where the first sensor and the second sensor scan the shiny surface of the coil with a laser. [Figure 15] FIG. 15 is a flowchart of the cushioning material detection process. [Figure 16] FIG. 16 is a diagram for explaining a grid for grouping measurement data of the received light intensity of a plurality of laser beams irradiated onto a coil and reflected in the irradiation direction. [Figure 17] FIG. 17 is a diagram for explaining a case where the first sensor and the second sensor use a laser to scan a marker portion made of an anti-reflection material of a cushioning material arranged on the circumferential surface of a coil. [Figure 18] FIG. 18 is a diagram showing the scanning positions of the coil on the floor by the lasers of the first and second sensors in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, some exemplary embodiments will be described with reference to the drawings. Here, the dimensions, materials, and other specific numerical values ​​shown in each embodiment are merely examples and do not limit the present disclosure unless otherwise specified. In addition, elements having substantially the same functions and configurations are given the same reference numerals to avoid repeated explanations, and elements not directly related to the present disclosure are not illustrated.

[0019] Fig. 1 is a perspective view showing a configuration of a conveying device 1 as an example of a device to which a cushioning material detection device and a cushioning material detection method according to an embodiment of the present disclosure are applied. Fig. 2 is a block diagram showing a schematic configuration of a control system of the conveying device 1 including the cushioning material detection device.

[0020] The conveying device 1 shown in FIG. 1 is, for example, an overhead crane installed at the top of a building such as a factory or a warehouse. The conveying device 1 is sometimes called a lifting machine. When the object to be conveyed is regarded as a load, the conveying device 1 may also be called a loading device. The cushioning material detection device and cushioning material detection method according to this embodiment can be implemented in the conveying device 1, for example. The cushioning material to be detected can be used when stacking the load to be conveyed by the conveying device 1. In FIG. 1, a coil C is shown as an example of the load to be conveyed.

[0021] As shown in FIG. 3, the coil C is formed by winding a long plate material 120 such as a steel plate, and has a cylindrical outer shape. A metal jig 130 may be attached to both ends in the width direction of the plate material 120 of the packaged coil C. The jig 130 fixes the plate material at the end of the winding of the coil C on the outer and inner circumferences of the coil C. Fixing the jig 130 can prevent the wound plate material 120 of the coil C from unwinding. The load to be transported is not limited to those called coils, and includes, for example, those called rolls. The surfaces of the plate material 120 of the coil C and the jig 130 exposed to the outside are finished to a smooth glossy surface.

[0022] The multiple coils C are temporarily stored on the premises of a building, for example, as shown in Fig. 1. In the following, in order to explain the arrangement of the multiple coils C and the operation of each part of the transport device 1, each direction is defined as follows. The Z direction is a direction along the vertical direction. The XY plane is a horizontal plane perpendicular to the Z direction. The X and Y directions are perpendicular to each other on the XY plane.

[0023] FIG. 4 is a perspective view showing an example of the arrangement of multiple coils C on a site inside a building. The site has a floor surface 100, which is a horizontal surface. Each coil C is installed on the side of the floor surface 100 with its own central axis parallel to the floor surface 100. In this embodiment, when each coil C is installed on the side of the floor surface 100, the axial direction of each coil C is along the Y direction, and the cross section perpendicular to the axial direction is parallel to the XZ plane. Furthermore, when each coil C is installed on the side of the floor surface 100, it is lined up along the X direction. Furthermore, each coil C is stacked in one layer or in multiple layers along the Z direction.

[0024] In the example of FIG. 4, a plurality of coils C are stacked in a maximum of three tiers. The coils C in the lowest tier are placed on the floor surface 100 via two rod-shaped sleepers 110 that form a pair. The extension direction of the sleepers 110 is along the axial direction of the coils C. The two sleepers 110, 110 that form a pair are adjacent to each other in the X direction. Such a pair of sleepers 110 can position the coils C to be placed and can also prevent the coils C from rolling. Meanwhile, the coils C in the middle tiers are stacked straddling the two coils C in the lowest tier that are adjacent to each other in the X direction. Similarly, the coils C in the top tier are stacked straddling the two coils C in the middle tier that are adjacent to each other in the X direction.

[0025] When the coils C are stacked, the plate material 120 of the coils C may be damaged due to contact between the coils C. As shown in FIG. 4, a buffer material is placed between the stacked coils C. The buffer material may be made of, for example, a flexible material having elasticity. In the example shown in FIG. 5, the buffer material 140 is formed in a long strip shape. As shown in FIG. 6, the buffer material 140 may be placed on the circumferential surface of the coil C in the lower stage that supports the stacked coils C, for example, with the longitudinal direction of the buffer material 140 facing the circumferential direction of the coil C. FIG. 6 shows a case where two buffer materials 140 are placed on the circumferential surface of the coil C, respectively, at positions near both ends in the width direction of the coil C.

[0026] The transport device 1 can estimate the position of a specific coil C already placed on the floor within the site, and then hold the coil C at the estimated position, lift it up, and move it to another location. This operation of lifting a desired coil C and moving it to another location may be referred to as a "lifting operation" below. The transport device 1 can also estimate a target position within the site where the specific coil C will be placed, and then suspend the coil C that has been moved from another location and place it at the estimated target position. This operation of suspending the coil C at the target position may be referred to as a "hanging operation" below.

[0027] As shown in FIG. 1, the conveying device 1 includes a girder 2, a runway 3, a trolley 4, a tong 5, a first sensor 6a and a second sensor 6b as distance sensors, a cab 7, and a control and calculation unit 8.

[0028] The girder 2 is a structure that movably supports a trolley 4 as a moving mechanism near the ceiling inside the building. The girder 2 includes two linear rigid parts that extend along the X direction and face each other while being spaced apart in the Y direction. In this case, although not shown, the two rigid parts can be integrated with each other on both sides of one end and the other end in the X direction.

[0029] The runway 3 is a traveling rail that supports the girder 2 movably near the ceiling inside the building. The runways 3 extend along the Y direction and are installed at two positions facing each other while being spaced apart in the X direction. The runway 3 may be installed, for example, on the wall of the building, or on an elevated platform installed on the floor surface 100 inside the building. One end of the girder 2 in the X direction is located on one runway 3, and the other end of the girder 2 in the X direction is located on the other runway 3. At least one end of the girder 2 in the X direction may be provided with a girder actuator 26 such as a motor (see FIG. 2). The girder actuator 26 is driven based on a movement command from the control calculation unit 8, so that the girder 2 can move along the Y direction on the runway 3. Hereinafter, the movement direction of the girder 2 relative to the runway 3 along the Y direction will be referred to as the "traveling direction".

[0030] The trolley 4 is a structure that is supported by two rigid parts on the girder 2 and can move freely along the X direction, and supports the tongs 5 ​​so that they can move freely along the Z direction. The trolley 4 is equipped with a trolley actuator 27 (see FIG. 2) such as a motor. The trolley actuator 27 is driven based on a movement command from the control and calculation unit 8, so that the trolley 4 can move along the X direction on the rigid part of the girder 2. Since the girder 2 can move along the Y direction, the trolley 4 can move to a target coordinate position on the XY plane. Hereinafter, the movement direction of the trolley 4 relative to the girder 2 along the X direction will be referred to as the "traverse direction."

[0031] The tongs 5 ​​are a gripping part that grips the coil C and moves up and down. Here, the trolley 4 includes a rotating drum (not shown) for hoisting and lowering the tongs 5 ​​via a wire rope 9, and a tongs actuator 28 (see FIG. 2), such as a motor, that applies a rotational force to the rotating drum. The tongs actuator 28 is driven based on a lift command from the control calculation unit 8, so that the tongs 5 ​​can move along the Z direction with the height of the trolley 4 as a reference.

[0032] The tongs 5 ​​also includes a base 10 and a pair of arms, a first arm 11a and a second arm 11b. The base 10 is connected to the wire rope 9 and supports the first arm 11a and the second arm 11b. The first arm 11a and the second arm 11b each extend downward from the base 10 along the Z direction and face each other in the Y direction. The first arm 11a is connected to one end of the base 10 in the Y direction, and the second arm 11b is connected to the other end of the base 10 in the Y direction. The first arm 11a and the second arm 11b can each slide along the Y direction while maintaining a posture along the Z direction.

[0033] Although not shown, suspender claws facing each other along the Y direction are provided at the lower end of each of the first arm 11a and the second arm 11b in the Z direction. The first arm 11a and the second arm 11b approach each other while the two suspender claws are positioned on the extension of the coil hole CH of the coil C to be transported, so that each suspender claw can enter the coil hole CH. That is, the first arm 11a and the second arm 11b can grip the coil C to be transported by approaching each other. Hereinafter, the state in which the first arm 11a and the second arm 11b are in a position to grip the coil C is referred to as the closed state of the arms. On the other hand, the first arm 11a and the second arm 11b can move away from each other to retract each suspender claw from the coil hole CH and release the grip of the coil C. Hereinafter, the state in which the first arm 11a and the second arm 11b are in a position to release the grip of the coil C is referred to as the open state of the arms. The trolley 4 is equipped with a coil gripping actuator 29 such as a motor (see FIG. 2). The coil gripping actuator 29 is driven based on an arm opening / closing command from the control calculation unit 8, so that the tongs 5 ​​can change the arm between an open state and a closed state.

[0034] The first sensor 6a and the second sensor 6b as distance sensors are each installed on the trolley 4 and scan and measure the distance to an object on the floor surface 100 side. The first sensor 6a and the second sensor 6b are the same type of sensor and are installed at different positions on the trolley 4. The first sensor 6a and the second sensor 6b in this embodiment are LiDAR (Light Detection And Ranging) as an example of a laser distance sensor that measures distance using a laser La (see FIG. 12).

[0035] The first sensor 6a and the second sensor 6b irradiate the laser La as a measurement signal below the trolley 4. The first sensor 6a and the second sensor 6b scan the peripheral surface of the coil C stacked on the floor surface 100 in the X direction along the lateral direction of the trolley 4 with the laser La. The scanning in the X direction of the laser La can be performed using an optical system such as a polygon mirror or a galvanometer mirror. The viewing angle of the laser La scanning in the X direction can be, for example, about plus or minus 45 [deg] with respect to a perpendicular line drawn from the first sensor 6a or the second sensor 6b to the floor 100. On the scanning line of the laser La on the peripheral surface of the coil C shown in FIG. 7, the laser La is irradiated to a number of measurement sites Pm at equal intervals in the X direction. In FIG. 7, the measurement sites Pm are illustrated only on a part of the peripheral surface of the coil C, but in reality, the measurement sites Pm are generated in all parts of the peripheral surface of the coil C irradiated with the laser La that scans the peripheral surface of the coil C in the X direction.

[0036] The scanning of the circumferential surface of the coil C by the laser La of the first sensor 6a and the second sensor 6b is repeatedly performed while changing the position of the trolley 4 on the girder 2 little by little in the X direction. While the laser light La of the first sensor 6a and the second sensor 6b is irradiated to one measurement site Pm, the laser light La is repeatedly irradiated while changing the irradiation angle in the XZ plane every time the position of the trolley 4 changes in the X direction. The first sensor 6a and the second sensor 6b receive the reflected light of the laser La reflected at the measurement site Pm of the coil C as a reflected signal of the measurement signal. The scanning of the circumferential surface of the coil C by the laser La of the first sensor 6a and the second sensor 6b may be repeatedly performed while changing the position of the trolley 4 on the runway 3 little by little in the Y direction. In this case, the circumferential surface of the coil C is scanned in a matrix by the laser La.

[0037] Each measurement site Pm is irradiated with the laser La from a plurality of irradiation directions by the first sensor 6a and the second sensor 6b of the trolley 4 moving in the X direction. The irradiation point (not shown) of the laser La irradiated to the measurement site Pm may be at the same position even if the irradiation direction of the laser La with respect to the measurement site Pm is different, and may be at a different position depending on the irradiation direction of the laser La with respect to the measurement site Pm. Although each measurement site Pm is shown as a point in FIG. 7, in consideration of the case where the irradiation point of the laser La differs depending on the irradiation direction of the laser La, it may be, for example, a surface area having a length in each of the X direction and the Y direction, rather than a point.

[0038] As shown in Fig. 1, the first sensor 6a and the second sensor 6b are installed on the trolley 4 at a fixed interval in the X direction. In the example of this embodiment, the first sensor 6a is installed on the side of the trolley 4 facing the positive side in the X direction, and the second sensor 6b is installed on the side of the trolley 4 facing the negative side in the X direction, so that they are located opposite each other across the main body of the trolley 4 in the X direction. This installation relationship has the advantage that the detection range is less likely to be blocked by the tongs 5 ​​supported by the trolley 4, and the detection range is less likely to be blocked by the coil C even when the tongs 5 ​​are gripping the coil C.

[0039] The driver's cab 7 is fixed to one end of the girder 2, and a driver who operates the transport device 1 is always present therein. A control and calculation unit 8, a user interface 20, and the like are installed in the driver's cab 7. The user interface 20 includes an input unit operated by the driver, and can transmit command information input by the driver to the control and calculation unit 8. The user interface 20 can also display estimated position information transmitted from the control and calculation unit 8.

[0040] The control and calculation unit 8 controls the operation of each component included in the conveying device 1 based on transport instructions from the driver via the user interface 20, or measurement data obtained from the distance sensors of the first sensor 6a and the second sensor 6b.

[0041] The control calculation unit 8, which is a computer, has, for example, a general-purpose microcontroller. The microcontroller has a CPU (Central Processing Unit) and a memory. The memory includes a ROM (Read Only Memory) and a RAM (Random Access Memory). The microcontroller can virtually construct multiple information processing circuits by, for example, executing a program stored in the memory with the CPU. The multiple information processing circuits can constitute the input / output unit and calculation unit of the control calculation unit 8. The input / output unit can acquire coil information from a database stored in a higher-level system on the user interface 20 side. Here, the coil information refers to information about the approximate placement position or target position of the coil C, or information about the size of the coil C, etc. The calculation unit can constitute the drive control unit 21, the estimation calculation unit 22, the acquisition unit 23, the identification unit 24, and the discrimination unit 25 of the control calculation unit 8, which will be described later. The acquisition unit 23, the identification unit 24, and the discrimination unit 25 can constitute the cushioning material detection device according to this embodiment.

[0042] In this embodiment, an example is shown in which multiple information processing circuits built in a microcontroller are realized by software. Of course, it is also possible to prepare dedicated hardware for executing each information processing of each of the units 21 to 25, which will be described later, to configure the information processing circuits. Also, the multiple information processing circuits may be configured by individual hardware. The dedicated hardware includes devices such as application specific integrated circuits (ASICs) arranged to execute the functions of each of the units 21 to 25, and conventional circuit components.

[0043] The drive control unit 21 transmits operation signals to various actuators included in the conveying device 1. First, the drive control unit 21 receives a conveying instruction or coil information from the user interface 20, and can specify a rough position to which the trolley 4 and the tongs 5 ​​are directed based on the conveying instruction or the coil information. The drive control unit 21 can also receive the placement position or target position of the coil C derived by the estimation calculation unit 22 from the estimation calculation unit 22. The estimation calculation unit 22 acquires measurement data from a distance sensor such as the first sensor 6a, and performs an estimation calculation of the position of the coil C related to the operation of the position estimation system or the position estimation method according to this embodiment based on the measurement data. The estimation calculation unit 22 can also transmit the calculated placement position or target position of the coil C to the drive control unit 21. Furthermore, the estimation calculation unit 22 can receive coil information required for the estimation calculation from the user interface 20. The acquisition unit 23, the identification unit 24, and the discrimination unit 25 will be described later.

[0044] In the conveying device 1 having the above configuration, as the main operations during automatic conveying, the lifting operation and the hanging operation are performed as described above. Hereinafter, the conveying process related to the lifting operation will be referred to as the "carrying out process," and the conveying process related to the hanging operation will be referred to as the "carrying in process."

[0045] FIG. 8 is a side view of a plurality of coils C, illustrating coils C to be transported or to be subjected to position estimation in the carrying-out process. In the example of FIG. 8, seven coils C are placed on the side of the floor surface 100. Among them, as the coils C in the lower stage, the first coil C1, the second coil C2, the third coil C3, and the fourth coil C4 are placed on the floor surface 100 in parallel along the X direction via the sleepers 110. Also, as the coils C in the upper stage, the fifth coil C5, the sixth coil C6, and the seventh coil C7 are placed while being supported by any two coils C in the lower stage. Specifically, the fifth coil C5 is placed on the first coil C1 and the second coil C2 as a base. The sixth coil C6 is placed on the second coil C2 and the third coil C3 as a base. The seventh coil C7 is placed on the third coil C3 and the fourth coil C4 as a base.

[0046] In the example of FIG. 8, it is assumed that the coil C to be transported, which is lifted by the transport device 1 and transported from the placement position, is the sixth coil C6 in the upper stage. In this case, the position estimation targets in this embodiment are the sixth coil C6 to be transported, and the fifth coil C5 and seventh coil C7 located on both sides of the sixth coil C6 in the X direction, that is, a total of three coils C. Among them, the estimated position of the sixth coil C6 is referred to as a position to which the tongs 5 ​​in an unclasped state are directed at the time of transport. On the other hand, the estimated positions of the fifth coil C5 and the seventh coil C7 are referred to as positions to be grasped in advance to avoid contact between the sixth coil C6 and the fifth coil C5 or the seventh coil C7 at the time of transport.

[0047] 9 is a side view of a plurality of coils C, illustrating the target position where the coil C to be transported is carried in the carrying-in process, and the coil C to be the target of position estimation. In the example of FIG. 9, six coils C, the first coil C1, the second coil C2, the third coil C3, the fourth coil C4, the fifth coil C5, and the seventh coil C7, are placed on the side of the floor surface 100, similar to the example of FIG. 8. In FIG. 9, the area drawn by the two-dot chain line and corresponding to the sixth coil C6 in FIG. 8 is the target position. Hereinafter, the coil C placed at the target position will be referred to as the sixth coil C6 for convenience.

[0048] In this case, the position estimation targets in this embodiment are the second coil C2 and the third coil C3 supporting the sixth coil C6 placed at the target position, and the fifth coil C5 and the seventh coil C7 located on both sides of the sixth coil C6 in the X direction, for a total of four coils C. Among these, the estimated positions of the second coil C2 and the third coil C3 are referred to as the target positions at the time of carrying in. Meanwhile, the estimated positions of the fifth coil C5 and the seventh coil C7 are referred to as positions that are grasped in advance to avoid contact between the sixth coil C6 and the fifth coil C5 or the seventh coil C7 at the time of carrying in.

[0049] Fig. 10 is a flow chart of the transport process. The transport process includes a carry-out process including a lifting operation and a carry-in process including a hanging operation. Below, each process included in the transport process will be explained separately for the case where the transport process is a carry-out process and the case where the transport process is a carry-in process.

[0050] In addition, the position of the coil C estimated in this embodiment is defined in a crane coordinate system based on an origin P0 set on the floor surface 100. As shown in Fig. 1, in this embodiment, the origin P0 is set at a corner of the moving range of the trolley 4. The crane coordinate system is represented by a lateral direction corresponding to the X direction, a traveling direction corresponding to the Y direction, and a height direction corresponding to the Z direction.

[0051] The control calculation unit 8 starts the transport process in response to a transport instruction from the driver via the user interface 20. As shown in FIG. 10, first, the control calculation unit 8 executes a position estimation target specification step S100. In the position estimation target specification step S100, the control calculation unit 8 specifies whether the transport process is a carry-out process or a carry-in process based on the transport instruction. If the transport process is a carry-out process, the control calculation unit 8 specifies which coil C is to be transported. On the other hand, if the transport process is a carry-in process, the control calculation unit 8 specifies which target position the coil C to be transported is to be transported to. Next, the control calculation unit 8 specifies the coil C whose position should be estimated, i.e., the position estimation target, based on the placement position of the coil C to be transported in the carry-out process or the target position where the coil C to be transported in the carry-in process is to be placed.

[0052] Furthermore, in the position estimation target identification step S100, the control and calculation unit 8 acquires coil information for each coil C that is a position estimation target from a database stored in a host system on the user interface 20 side. Here, the coil information refers to information on the approximate placement position or target position of the coil C, information on the size of the coil C, etc.

[0053] Next, the control calculation unit 8 executes a primary planar movement process. In the primary planar movement process, the control calculation unit 8 moves the trolley 4 toward a position above the placement position of the coil C or the target position. When the transport process is an unloading process, the trolley 4 not suspending any coil C is moved toward a position above the placement position of the coil C to be transported. On the other hand, when the transport process is a loading process, the trolley 4 suspending the coil C to be transported is moved toward a position above the target position that is preset on the floor surface 100 side. The primary planar movement process includes a high-speed movement process S200, a measurement movement process S300, and a cushioning material correction movement process S400.

[0054] The high-speed moving step S200 is a step of moving the trolley 4 to a position above the rough placement position or target position specified from the transport instruction at a speed faster than the moving speed in the measurement moving step S300. At this time, the drive control unit 21 drives the girder actuator 26 or the trolley actuator 27 with the XY coordinates corresponding to the rough placement position or the position above the target position as the moving position. The XY coordinate position as the moving position is the position where the subsequent measurement moving step S300 is started. In other words, at this stage, the control calculation unit 8 does not specifically grasp the placement position or target position of the coil C. After the high-speed moving step S200, the control calculation unit 8 proceeds to the measurement moving step S300.

[0055] The measurement movement step S300 is a step that includes a step of estimating the position of the coil C designated as the position estimation target. This measurement movement step S300 will be described in detail below. After the measurement movement step S300, the control and calculation unit 8 proceeds to a correction movement step S400.

[0056] The correction movement process S400 is a process for correctively moving the trolley 4 from the position of the trolley 4 at the end of the measurement movement process S300 to the target coordinates of the trolley 4 determined based on the position of the coil C estimated in the measurement movement process S300. At this time, the drive control unit 21 drives the girder actuator 26 or the trolley actuator 27 with the XY coordinates corresponding to the target coordinates of the trolley 4 as the movement position. With the end of this correction movement process S400, the XY coordinate position of the trolley 4 is determined when the coil C to be transported is lifted from the placement position or when the lifted coil C to be transported is lowered to the target position.

[0057] Next, the control calculation unit 8 executes the tongs lowering step S500. In the tongs lowering step S500, the control calculation unit 8 lowers the tongs 5 ​​to the target coordinates of the tongs 5 ​​determined based on the position of the coil C estimated in the measurement movement step S300. At this time, the drive control unit 21 drives the tongs actuator 28 with the Z coordinate corresponding to the target coordinates of the tongs 5 ​​as the lift position. When the tongs lowering step S500 is completed, if the transport step is the unloading step, the tongs 5 ​​is in a position where it can grip the coil C to be transported. On the other hand, if the transport step is the loading step, the coil C to be transported is placed at the target position.

[0058] Next, the control calculation unit 8 executes a tongs operation step S600. When the transport step is a carry-out step, the tongs operation step S600 is a step of making the tongs 5 ​​grip the coil C to be transported. On the other hand, when the transport step is a carry-in step, the tongs operation step S600 is a step of making the tongs 5 ​​release the grip of the coil C and completely place the coil C at the target position. At this time, the drive control unit 21 appropriately drives the coil gripping actuator 29 to change the arm of the tongs 5 ​​between an open state and a closed state.

[0059] Next, the control calculation unit 8 executes a tongs lifting step S700. In the tongs lifting step S700, when the transport step is the carry-out step, the tongs 5 ​​gripping the coil C are lifted to the top. On the other hand, when the transport step is the carry-in step, the tongs 5 ​​not gripping the coil C are lifted to the top. At this time, too, the drive control unit 21 can lift the tongs 5 ​​by driving the tongs actuator 28.

[0060] Then, the control calculation unit 8 executes a secondary planar movement step S800. In the secondary planar movement step S800, the drive control unit 21 moves the trolley 4 away from the placement position of the coil C or a position above the target position. When the transport step is a carry-out step, in the secondary planar movement step S800, the trolley 4 suspending the coil C to be transported is moved to transport the coil C to the desired position. On the other hand, when the transport step is a carry-in step, the trolley 4 not suspending the coil C is retreated to the desired position. This completes the series of transport steps.

[0061] Next, the measurement movement step S300 will be described in detail. FIG. 11 is a flowchart of the measurement movement step S300. In the measurement movement step S300, the first sensor 6a or the second sensor 6b, which is a distance sensor, scans the peripheral surface of the coil C on one scanning line for a plurality of frames while moving along the transverse cross-sectional direction of the coil C, which is the position estimation target, with the laser La. Also, in the measurement movement step S300, the position of each measurement site Pm on the scanning line is measured using the laser La, and the position of the coil C is estimated. That is, in the measurement movement step S300, the measurement step S310 by the distance sensor and the step of deriving the position of the coil C based on the measurement data obtained in the measurement step S310 and detecting the cushioning material 140 of the coil C are performed in parallel. In FIG. 11, the flow of the measurement step S310 is shown on the left side, and the flow of deriving the position of the coil C and detecting the cushioning material 140 of the coil C is shown on the right side in chronological order.

[0062] Fig. 12 is a perspective view for explaining a basic operation of the measurement movement in the measurement step S310. Fig. 12 corresponds to the drawing in Fig. 1 which is a perspective view of the transport device 1. Fig. 12 illustrates a case where the transport step is a loading step and the first sensor 6a performs a scan measurement in the measurement movement step S300.

[0063] In the measurement step S310, the first sensor 6a scans and measures the coil C already placed while moving above it in the X direction, which is the lateral direction of the trolley 4, to obtain measurement data from multiple viewpoints. The viewpoints correspond to the relative positions of the first sensor 6a with respect to the coil C whose position is to be estimated in the X direction. The measurement data from multiple viewpoints refers to measurement data obtained by measuring the light intensity of reflected light from the irradiation points of multiple lasers La irradiated from the first sensor 6a at multiple locations with different positions in the X direction to one measurement site Pm of the coil C whose position is to be estimated. The light intensity of the measurement data is the light intensity measured for the reflected light reflected in the irradiation direction of the laser La with respect to the irradiation point. When the measurement site Pm is a surface area, the measurement site Pm may be an area represented by a set of a specific irradiation point and its neighboring irradiation points, or may be an area set by dividing the space irradiated with the laser La into a lattice shape in advance, regardless of the position of the irradiation point.

[0064] In FIG. 12, three coils C that can be used as position estimation targets are placed on a sleeper 110. A scan range defined by a specific viewing angle is shown as the irradiation range of the laser La. Furthermore, in FIG. 12, a line-shaped point cloud for three scans arranged in the Y direction is shown on the three coils C. However, in reality, measurements may be performed on four or more lines. By arranging many measurement lines in this way, if a measurement line has a large variation in the point cloud compared to other measurement lines, the measurement line with the large variation can be excluded in advance from the measurement data used to estimate the position of the coil C, thereby improving the accuracy of position estimation.

[0065] Here, assume that the trolley 4 moves closer to the origin P0 in the X direction. In this case, if the coil C, the position of which is to be estimated, is placed directly below the trolley 4, it may be difficult for the first sensor 6a to detect the coil C directly below because the irradiation range of the laser La is blocked by the coil C held by the tongs 5. In such a case, the second sensor 6b, which is installed on the opposite side of the first sensor 6a in the X direction on the trolley 4, is used as a distance sensor instead of the first sensor 6a, thereby making it possible to suitably detect the coil C directly below.

[0066] When the measurement process S310 is started following the start of the measurement movement process S300, the estimation calculation unit 22 then derives the position of each coil C that requires position estimation. Here, as an example, the second coil C2, which is one of the position estimation targets, will be described with reference to the multiple coils C shown in Fig. 9 related to the carry-in process.

[0067] First, the estimation calculation unit 22 executes a coordinate conversion step S320. In the coordinate conversion step S320, the measurement data from multiple viewpoints acquired one by one in the measurement step S310 is converted into coordinates fixed to the building by correcting the positions of the distance sensors such as the first sensor 6a. By this coordinate conversion, isolated noise or a point cloud corresponding to a part of the structure of the transport device 1 can be removed in advance.

[0068] Next, the estimation calculation unit 22 executes a coil position derivation step S340 after the end of the measurement step S310 (S330). The end of the measurement step may be when the trolley 4 reaches the end point of the measurement movement. In the coil position derivation step S340, the position of the second coil C2 is derived. The position of the second coil C2 can be derived using a known method, such as the methods described in Japanese Patent No. 3150589, Japanese Patent Application Publication No. 2001-335281, and Japanese Patent Application Publication No. 2019-52019. The method described in the specification of Japanese Patent Application No. 2022-159622 by the present applicant may be used to derive the position of the second coil C2. The position derivation for the coil C of the position estimation target other than the second coil C2 can also be performed in the same manner as the position derivation of the second coil C2.

[0069] Up to this point, the measurement movement step S300 has been described with reference to the multiple coils C shown in Fig. 9 related to the carry-in step. On the other hand, when the transport step is the carry-out step, the measurement movement step S300 can be similarly executed by defining each part as shown in Fig. 8.

[0070] Incidentally, when the coil C is carried into the target position of the tongs 5, the coil C may be damaged due to contact between the coils C. In order to avoid damage to the coil C due to contact between the coils C, it is effective to place a cushioning material 140 on the circumferential surfaces of the two coils C below the target position. For example, when the coil C at the target position is carried out to another location and then the next coil C is carried into the target position, it is preferable to leave the cushioning material 140 between the coil C before being carried out from the target position and the coil C below the target position on the circumferential surface of the lower coil C even after the coil C is carried out. However, if the cushioning material 140 is attached to the coil C to be carried out and carried out together, the next coil C to be carried into the target position will be stacked directly on the lower coil C without sandwiching the cushioning material 140. If the stacked coils C above and below come into contact with each other, the coil C may be damaged. In this embodiment, in the measurement movement process S300 shown in FIG. 11, the acquisition unit 23, the identification unit 24, and the discrimination unit 25 execute the cushioning material detection process S350. In the cushioning material detection step S350, it is detected whether or not the cushioning material 140 is disposed on the circumferential surface of the coil C below the target position.

[0071] The detection target of the buffer material 140 may include the coil C below the target position that supports the coil C to be carried to the target position. The detection target of the buffer material 140 may be, for example, the same coil C as the position estimation target in this embodiment. For example, when the target position is an area corresponding to the sixth coil C6 in Fig. 8, the detection target of the buffer material 140 may be the second coil C2, the third coil C3, the fifth coil C5, and the seventh coil C7 in Fig. 9, which are the same as the position estimation targets.

[0072] As shown in FIG. 5, in this embodiment, the cushioning material 140 may have a marker section 150 on the surface. The marker section 150 may be made of, for example, a retroreflective material. The retroreflective material reflects light incident on the surface in the direction of incidence, regardless of the angle of incidence of the light to the retroreflective material. The first sensor 6a or the second sensor 6b that outputs the laser La is present on the extension line of the incident direction. The reflectance of light by a diffuse reflection material having an uneven surface depends on the degree of unevenness, but can be considered to be, for example, about 5 to 90%. The reflectance of the retroreflective material is 200% or more in terms of the diffuse reflection material ratio. The marker section 150 may be configured to cover the entire surface of the cushioning material 140, or may be configured to cover a part of the surface of the cushioning material 140. FIG. 5 shows a case where the marker section 150 is configured to cover only the central part of the surface of the cushioning material 140 in the longitudinal direction. For example, the cushioning material 140 may be made of a retroreflective material, and the cushioning material 140 itself may constitute the marker portion 150.

[0073] 13 shows a case where the first sensor 6a or the second sensor 6b uses a laser La to scan a marker portion 150 made of a retroreflective material of a cushioning material 140 arranged on the circumferential surface of a coil C. The laser La that has scanned the marker portion 150 of the coil C is reflected toward the first sensor 6a or the second sensor 6b with high reflectivity, whether at the solid line position where the first sensor 6a or the second sensor 6b directly faces the coil C or the virtual line position where the first sensor 6a or the second sensor 6b does not directly face the coil C.

[0074] FIG. 14 shows a case where the first sensor 6a or the second sensor 6b scans the glossy surface of the coil C with the laser La. When the first sensor 6a or the second sensor 6b is at a virtual line position shifted from a position directly facing the coil C, the reflectance of the laser La that has scanned the glossy surface of the coil C toward the first sensor 6a or the second sensor 6b is lower than that when the marker unit 150 is scanned. However, when the first sensor 6a or the second sensor 6b is at a position directly facing the coil C, the laser La that has scanned the glossy surface of the coil C is reflected toward the first sensor 6a or the second sensor 6b with high reflectance, as in the case of scanning the marker unit 150 with the laser La. The reflectance of the laser La on the glossy surface of the coil C may be close to 200% with a diffuse reflection material ratio. If the laser La is reflected by the glossy surface of the coil C with such a high reflectivity, then when detecting the cushioning material 140 based on the received light intensity of the reflected light of the laser La, the glossy surface of the coil C may be mistakenly recognized as the marker portion 150.

[0075] The lasers La as measurement signals output by the first sensor 6a and the second sensor 6b are irradiated from multiple directions onto the marker portion 150 and the glossy surface of the coil C. For example, at one or multiple adjacent measurement sites Pm, it is confirmed whether the received light intensity of the reflected light of the multiple lasers La irradiated from multiple directions is high overall or high only in a specific irradiation direction. By checking the received light intensity of the reflected light of the multiple lasers La, it is possible to determine whether the measurement site Pm is a point on the marker portion 150 or a point on the glossy surface of the coil C.

[0076] FIG. 15 is a flowchart of the cushioning material detection step S350 following the coil position derivation step S340 in FIG. 11. First, the acquisition unit 23 executes the coil position information acquisition step S351. The coil position information acquisition step S351 is a step of acquiring the position information of the coil C, which is a load on the floor, as the position information of the load on the floor. The position information of the coil C can be the coil information acquired by the control calculation unit 8 in the position estimation target identification step S100 in FIG. 10. The position information of the coil C may be the coil information acquired from a database stored in a higher-level system on the user interface 20 side in FIG. 2. The acquisition unit 23 calculates the points of the height of the coil center identified from the size information, which is the dimensional information of the coil information of the coil C through which the laser La, which is the measurement signal, passes, as multiple virtual passing points Pv during the movement of the trolley 4 on a plane parallel to the floor surface 100 on which the coil C is placed. The acquisition unit 23 acquires, by estimation, position information of the coil C on the floor surface 100 based on the virtual passing point Pv that is closest to the coil C on the floor surface 100 as viewed from the conveyance device 1. The acquisition unit 23 may acquire, as the position information of the coil C, position information including the coil end Pe of the coil C whose position is to be estimated, derived by the estimation calculation unit 22 in the coil position derivation step S370 in FIG.

[0077] The identifying unit 24 of the control calculation unit 8 in FIG. 1 executes a measurement site identifying step S352. The measurement site identifying step S352 is a step of identifying a measurement site Pm that satisfies a predetermined condition from among a plurality of measurement sites Pm on the circumferential surface of the coil C on the floor surface 100 on which the coils C are stacked, which is scanned by the laser La. The measurement site Pm that satisfies the predetermined condition is a measurement site Pm where a plurality of reflected lights of a plurality of lasers La that are irradiated from different irradiation directions are received at a predetermined light receiving intensity as a predetermined signal intensity. The predetermined light receiving intensity can be, for example, the light receiving intensity of the reflected light of the laser La reflected at the measurement site Pm on the marker part 150 of the cushioning material 140 by the first sensor 6a or the second sensor 6b. The predetermined light receiving intensity is a light receiving intensity that corresponds to the signal reflectance at the marker part 150. The identification unit 24 identifies a measurement site Pm that receives, within a detection range in which the coil C, the position of which is to be estimated, the reflected light of the laser La irradiated from a plurality of irradiation directions at one measurement site Pm by the first sensor 6a or the second sensor 6b, at a predetermined light receiving intensity in each irradiation direction. The measurement site Pm that receives the reflected light of the laser La at a predetermined light receiving intensity appears exclusively in a portion of the coil C, the position of which is to be estimated, where the marker portion 150 of the cushioning material 140 is disposed. In FIG. 7, the measurement site Pm that receives the reflected light of the laser La irradiated from a plurality of irradiation directions at a predetermined light receiving intensity appears in a portion of the coil C, the position of which is to be estimated, near both ends in the width direction (Y direction) of the coil C, surrounded by an elliptical imaginary line (dotted and dashed line).

[0078] The identification unit 24 may identify an extraction range Ar2 including a portion of the circumferential surface of the coil C on the floor surface 100 where the stacked coils C make contact. The extraction range Ar2 may be identified, for example, in the X direction based on size information of the coil C acquired by the acquisition unit 23. The extraction range Ar may be identified, for example, in the Y direction based on the position of the coil C whose position is to be estimated, estimated by the estimation calculation unit 22. When the identification unit 24 identifies the extraction range Ar2, the identification unit 24 may identify a measurement site Pm where the reflected light of the laser La is received at a predetermined light receiving intensity from among the measurement sites Pm within the extraction range Ar2. By limiting the detection range for identifying the measurement site Pm to the extraction range Ar2 identified based on size information, which is the position information of the coil C acquired by the acquisition unit 23, the processing load on the identification unit 24 can be reduced and the measurement site Pm can be identified efficiently.

[0079] In the measurement site identification step S352 in FIG. 15, the identification unit 24 may, for example, divide the space through which the laser La irradiated toward the coil C passes into a grid (lattice) G as a plurality of areas divided into a certain size in the X direction and the Y direction as shown in FIG. 16. The grid G ​​is a virtual area obtained by dividing a plane parallel to the floor surface 100 on which the coil C is placed, into the X direction and the Y direction, which are the moving directions of the girder 2 and the trolley 4 of the conveying device 1. The identification unit 24 may accumulate the received light intensity measured in the irradiation direction of the coil C of the reflected light of the laser La irradiated to the coil C after passing through one grid G ​​as measurement data that is information on the received intensity of the reflected signal related to one measurement site Pm. For example, the identification unit 24 may group and accumulate information on the signal intensity of each reflected signal as measurement data of the reflected signal reflected at each of a plurality of irradiation points included in one measurement site Pm, or may accumulate the information in association with a measurement site including a plurality of irradiation points. The measurement data may be accumulated, for example, in the memory of the microcontroller of the control and calculation unit 8. The symbol Ps in FIG. 16 shows a schematic of the irradiation point of the laser La that has passed through the grid G ​​and irradiated the coil C. In FIG. 16, a part of the irradiation point Ps of the laser La that has passed through the grid G ​​is shown as a representative for one grid G. The grid G ​​is a virtual range in space, and the irradiation point Ps does not exist on the grid G. The irradiation point Ps exists on the coil C to which the laser La that has passed through the grid G ​​is irradiated, or on the cushioning material 140 on the coil C. The irradiation point Ps exists in the space behind the grid G, which corresponds to the back side of the paper surface of FIG. 16. In the measurement site specification step S352, the specification unit 24 may specify a measurement site Pm where a plurality of reflected lights reflected in each irradiation direction at the irradiation point Ps of the laser La are received with a predetermined light receiving intensity, based on the measurement data accumulated for one measurement site Pm. The position of the irradiation point Ps of the laser La may shift when the irradiation direction of the laser La changes. In this case, it becomes difficult to generate an irradiation point Ps where the laser La is irradiated from a plurality of irradiation directions, and it is difficult to find an irradiation point Ps where the reflected light of the laser La from each irradiation direction is received with a predetermined light receiving intensity.The laser La that has passed through one grid G ​​is assumed to be irradiated onto the same measurement site Pm even if the irradiation point Ps is different, and it is relatively easier to find the measurement site Pm where the reflected light of the laser La in each irradiation direction is received with a predetermined light receiving intensity than the irradiation point Ps. By identifying the measurement site Pm where the reflected light of the laser La that has passed through the same grid G ​​is received with a predetermined light receiving intensity, the identifying unit 24 can identify the measurement site Pm that satisfies the conditions even if the position of the irradiation point Ps of the laser La shifts depending on the irradiation direction of the laser La.

[0080] The identification unit 24 may have a configuration for suppressing the influence of some measurement data whose received light intensity is extremely different from that of the reflected light of other irradiation points Ps of the same measurement site Pm when identifying the measurement site Pm where the reflected light in each irradiation direction is received at a predetermined light receiving intensity. This configuration may, for example, perform statistical processing on the measurement data accumulated for one measurement site Pm. By accumulating the measurement data for each measurement site Pm, the identification unit 24 can perform statistical processing to identify the measurement site Pm where the reflected light in each irradiation direction is received at a predetermined light receiving intensity based on the measurement data for one measurement site Pm. By this statistical processing, the identification unit 24 can suppress the influence of some measurement data on the identification result of the measurement site Pm where the reflected light in each irradiation direction is received at a predetermined light receiving intensity based on the measurement data accumulated for one measurement site Pm. By grouping the measurement data for one measurement site Pm or linking it to a measurement site Pm including multiple irradiation points Ps, multiple measurement data can be stored in association with one measurement site Pm. The part of the measurement data can be, for example, less than half of the measurement data stored for one measurement site Pm. The statistical processing performed by the identifying unit 24 may be, for example, a process of obtaining an average or median of the received light intensity from the received light intensity of the reflected light of the measurement data stored for one measurement site Pm. The statistical processing performed by the identifying unit 24 may be, for example, a process performed after removing outliers of the received light intensity that is extremely different from the reflected light of other irradiation points Ps of the same measurement site Pm from the received light intensity of the reflected light of the measurement data stored for one measurement site Pm. The statistical processing may be, for example, a process of obtaining an average or median of the received light intensity. Some specific examples of the statistical processing performed by the identifying unit 24 will be described below.

[0081] The identification unit 24 may, for example, eliminate measurement data of a light receiving intensity that is significantly different from the average value of the light receiving intensity from the deviation of the light receiving intensity of the reflected light by each measurement data accumulated for one measurement site Pm. The identification unit 24 can identify a measurement site Pm that satisfies a predetermined condition based on the measurement data remaining after eliminating the measurement data that is significantly different from the average value. The identification unit 24 may, for example, average the light receiving intensity of each measurement data accumulated for one measurement site Pm. The identification unit 24 can identify a measurement site Pm that satisfies a predetermined condition based on the average value of the light receiving intensity. In this case, the identification unit 24 identifies a measurement site Pm that satisfies a predetermined condition based on a stable light receiving intensity of the reflected light in the irradiation direction of the laser La. The identification unit 24 can identify a measurement site Pm where the light receiving intensity of the reflected light is statistically stable at a desired light receiving intensity among the measurement sites Pm where measurement data is accumulated based on the measurement data of the accumulated measurement site Pm.

[0082] For example, the identifying unit 24 may set the light receiving intensity calculated from the light receiving intensity of the reflected light of the lasers La that have passed through each grid G ​​and received by the first sensor 6a or the second sensor 6b as the measurement data of the representative point Ptp of the grid G. The representative point Ptp is not a physically existing point, but a virtual point that is set corresponding to one grid G. The measurement data of the representative point Ptp may be, for example, a representative value of the light receiving intensity of the reflected light that has passed through one grid G ​​and reflected at the irradiation point in the irradiation direction of the laser La. The representative value may be, for example, a median value of a population of the light receiving intensity of the reflected light of the lasers La that have passed through one grid G ​​and reflected from the irradiation point in the irradiation direction of each laser La. When the representative value of the grid G ​​is a predetermined light receiving intensity, the identifying unit 24 may identify a range including the irradiation points of all the lasers La that pass through the grid G ​​as the measurement site Pm where the reflected light of the laser La is received at a predetermined light receiving intensity. Instead of calculating the representative value for each grid G, a representative value for each pitch in each direction may be calculated for each predetermined pitch in the X direction and for each predetermined pitch in the Y direction. In this case, the identification unit 24 regards the range of one pitch as one area in each of the X and Y directions, and calculates a representative value for each area in each direction from measurement data of the received light intensity of the reflected light of the laser La that has passed through each area and is reflected from the irradiation point in the irradiation direction of the laser La. The identification unit 24 calculates a representative value for one grid G ​​from the calculated representative values ​​for each area in each direction, and can identify a measurement site Pm that satisfies a predetermined condition by using this as measurement data for one measurement site Pm.

[0083] In the measurement site identification step S352, the identification unit 24 may compare, for example, the light receiving intensity of the reflected light from each measurement site Pm received by the first sensor 6a or the second sensor 6b, the light receiving intensity after the deviation processing or averaging described above, and the representative value with a predetermined threshold value. In the measurement site identification step S352, the identification unit 24 identifies the measurement site Pm where the reflected light of the laser La is received at a predetermined light receiving intensity. Even if the laser La is totally reflected by the glossy surface of the coil C at one irradiation point in the measurement site Pm, the influence of the light receiving intensity of the reflected light from that irradiation point is excluded in the light receiving intensity after the deviation processing or averaging of the reflected light, and the representative value of the measurement site Pm. The predetermined threshold value can be set by the reflectance, and for example, the reflectance of 150% in the diffuse reflection material ratio. The threshold value may be set in consideration of the decrease in the light receiving intensity due to dirt and deterioration of the optical elements in the first sensor 6a and the second sensor 6b. In this case, for example, the threshold value may be the average value of the light receiving intensities of the reflected light for one measurement site Pm, plus twice the variance of the light receiving intensities, plus a fixed margin value. The margin value may be, for example, a reflectance of 50% in terms of the diffuse reflection material ratio.

[0084] The identification unit 24 may determine that the measurement site is a point on the marker unit 150, for example, when the number of light receiving intensities equal to or greater than a predetermined threshold among the light receiving intensities of a plurality of reflected lights related to one measurement site Pm is equal to or greater than a predetermined threshold. In this case, the identification unit 24 determines that the measurement site is a point on the glossy surface, when the number of light receiving intensities equal to or greater than the predetermined threshold is less than a predetermined number. For example, when the representative value of one grid G ​​is equal to or greater than a predetermined threshold, the identification unit 24 may determine that an area including an irradiation point of the laser La that has passed through the grid G ​​is one measurement site Pm, and that the measurement site Pm is a portion on the marker unit 150. In this case, the identification unit 24 determines that the measurement site Pm including an irradiation point of the laser La that has passed through the grid G ​​is a portion on the glossy surface, when the representative value of the grid G ​​is less than a predetermined threshold.

[0085] The discrimination unit 25 of the control calculation unit 8 executes a cushioning material discrimination step S353. The cushioning material discrimination step S353 is a step of discriminating the cushioning material 140 arranged on the circumferential surface of the coil C on the floor surface 100. The discrimination unit 25 can discriminate that the cushioning material 140 is present, for example, when a plurality of measurement sites Pm determined by the identification unit 24 to be points or parts on the marker unit 150 are identified consecutively in at least one of the X direction and the Y direction.

[0086] That is, the discrimination unit 25 can discriminate the cushioning material 140 of the coil C based on the measurement site Pm where the reflected light of the laser La reflected at the irradiation point of the measurement site Pm is received by the first sensor 6a or the second sensor 6b at a predetermined light receiving intensity. Alternatively, the discrimination unit 25 can discriminate the cushioning material 140 arranged on the circumferential surface of the coil C on the floor surface 100 based on the distribution of the plurality of measurement sites Pm where the first sensor 6a or the second sensor 6b receives the reflected light at a predetermined light receiving intensity. As an example of the distribution of the plurality of measurement sites Pm, the cushioning material 140 arranged on the circumferential surface of the coil C on the floor surface 100 may be discriminated based on the size of an area group that is a collection of grids G as areas corresponding to the measurement site Pm where the reflected light is received at a predetermined light receiving intensity. By discriminating based on the size of the area group, the discrimination unit 25 can discriminate the presence or absence of the cushioning material 140 using as an index whether or not the plurality of measurement sites Pm where the reflected light is received at a predetermined light receiving intensity are distributed in a size corresponding to the marker unit 150.

[0087] The acquisition unit 23, the identification unit 24, and the discrimination unit 25 execute the coil position information acquisition step S351, the measurement region identification step S352, and the cushioning material discrimination step S353, thereby executing the cushioning material detection method according to this embodiment.

[0088] According to the cushioning material detection device of this embodiment, it is possible to detect the cushioning material 140 present on the circumferential surface of the coil C, the position of which is to be estimated, based on the light receiving intensity of the reflected light received from the measurement site Pm of the laser light La that scans the circumferential surface of the coil C. The cushioning material detection device of this embodiment can suitably detect the cushioning material 140 present on the circumferential surface of the coil C below the target position where the coil C to be carried is to be stacked, when the coil C is carried to the target position. In the conveyance device 1 in which the cushioning material detection device of this embodiment is implemented, it is possible to confirm whether the cushioning material 140 exists at the carrying position of the coil C before carrying the coil C to the target position. By stacking the coil C to be carried to the target position on the coil C having the cushioning material 140 arranged on the circumferential surface, it is possible to avoid damage to the coil C due to contact between the coils C.

[0089] In the above-described embodiment, the marker portion 150 of the cushioning material 140 is made of a retroreflective material, but the marker portion 150 may be made of an anti-reflective material. The anti-reflective material may be, for example, a member having a substrate with an AR coating (Anti Reflection Coating) applied to its surface, or an ND (Neutral Density) filter.

[0090] 17 shows a case where the first sensor 6a or the second sensor 6b uses a laser La to scan a marker portion 150 made of an anti-reflection material of a cushioning material 140 arranged on the circumferential surface of a coil C. The laser La that has scanned the marker portion 150 of the coil C is hardly reflected in the direction of the first sensor 6a or the second sensor 6b, whether it is at the solid line position where the first sensor 6a or the second sensor 6b directly faces the coil C or at the virtual line position where it does not directly face the coil C.

[0091] As shown in Fig. 14, when the first sensor 6a or the second sensor 6b scans the glossy surface of the coil C with the laser La, the laser La is reflected with high reflectance by the glossy surface of the coil C. The light intensity of the reflected light of the laser La received by the first sensor 6a or the second sensor 6b is highest at the solid line position where the first sensor 6a or the second sensor 6b directly faces the coil C, and decreases as the first sensor 6a or the second sensor 6b moves away from the position directly facing the coil C. If the light intensity of the reflected light of the laser La is clearly different when the glossy surface of the coil C is scanned with the laser La and when the marker portion 150 made of the anti-reflection material is scanned, the marker portion 150 of the cushioning material 140 can be detected based on the light intensity of the reflected light.

[0092] For example, when the angle between the perpendicular line to the circumferential surface of the coil C exceeds a predetermined angle range, the direction of the reflected light of the laser La reflected on the glossy surface of the coil C deviates significantly from the direction of the first sensor 6a or the second sensor 6b. When the direction of the reflected light deviates significantly from the direction of the first sensor 6a or the second sensor 6b, the light intensity of the reflected light received by the first sensor 6a or the second sensor 6b decreases. When the light intensity of the reflected light decreases, it becomes difficult to distinguish between the scanning of the glossy surface of the coil C and the scanning of the marker unit 150 by the anti-reflection material, based on the light intensity of the reflected light received by the first sensor 6a or the second sensor 6b. Therefore, the detection of the marker unit 150 based on the light intensity of the reflected light of the laser La may be limited to the reflected light of the laser La irradiated on the coil C from a direction in which the angle between the perpendicular line to the circumferential surface of the coil C is within a predetermined angle range. The direction within the predetermined angle range includes the direction in which the first sensor 6a or the second sensor 6b faces the coil C. 17, the predetermined angle range can be a range of plus or minus 30° with respect to the direction in which the first sensor 6a or the second sensor 6b faces the coil C, which is the direction of the perpendicular to the circumferential surface of the coil C. By limiting the received light intensity of the reflected light used to identify the measurement site Pm to the reflected light of the laser La irradiated within a predetermined angle range with respect to the perpendicular to the circumferential surface of the coil C, it is possible to easily distinguish between scanning the glossy surface of the coil C and scanning the marker portion 150 made of the anti-reflective material by the received light intensity of the reflected light.

[0093] When the marker section 150 of the cushioning material 140 is made of an anti-reflective material, the identification unit 24 of the control and calculation unit 8 in FIG. 1 identifies a measurement section Pm that satisfies a predetermined condition from among a plurality of measurement sections Pm of the coil C on the floor surface 100 in a measurement section identification step S352 in FIG. 15. In the measurement section Pm that satisfies the predetermined condition, the predetermined light receiving intensity of the reflected light of the laser La received in the irradiation direction of the laser La can be, for example, a low numerical intensity close to zero. This light receiving intensity is an intensity corresponding to the reflectance of the anti-reflective material. The identification unit 24 may set, for example, a threshold value corresponding to the predetermined light receiving intensity. The identification unit 24 may determine that the measurement section is a point on the marker section 150 made of an anti-reflective material when the light receiving intensity of the reflected light by the first sensor 6a or the second sensor 6b is equal to or less than the set threshold, and may determine that the measurement section is a point on a glossy surface when the light receiving intensity exceeds the threshold.

[0094] When the marker unit 150 is made of a retroreflective material, the measurement sites Pm where the first sensor 6a or the second sensor 6b receives the reflected light of the laser La with high light intensity are concentrated in the portions near both ends in the width direction (Y direction) of the coil C, as shown by the imaginary line of the ellipse in Fig. 7. When the marker unit 150 is made of an anti-reflective material, the measurement sites Pm where the received light intensity of the reflected light of the laser La by the first sensor 6a or the second sensor 6b is almost zero are concentrated in the portions near both ends in the width direction (Y direction) of the coil C. In Fig. 18, the measurement sites Pm where the received light intensity of the reflected light is almost zero are indicated by many "○" dots in the imaginary line of the ellipse.

[0095] The coil position information acquisition step S351 and the cushioning material discrimination step S353 in FIG. 15 can be performed in the same manner as when the marker unit 150 is made of a retroreflective material. Even when the marker unit 150 is made of an antireflective material, the acquisition unit 23, the identification unit 24, and the discrimination unit 25 execute the coil position information acquisition step S351, the measurement site identification step S352, and the cushioning material discrimination step S353, thereby executing the cushioning material detection method according to this embodiment. However, the measurement site Pm that satisfies the predetermined condition in the measurement site identification step S352 is the measurement site Pm where the reflected light of the laser La that is irradiated to the measurement site Pm from a position directly facing the coil C and reflected in the irradiation direction is received with a predetermined light receiving intensity as a predetermined signal intensity. Even when the marker unit 150 is made of an antireflective material and the cushioning material detection method is executed as in this embodiment, the same effect as when the marker unit 150 is made of a retroreflective material and the cushioning material detection method is executed can be obtained.

[0096] According to the embodiment described above, it is possible to provide a cushioning material detection device and a cushioning material detection method according to the present disclosure.

[0097] In the above-described embodiment, the load on the floor and the load stacked on the load on the floor are both coils C formed by winding the plate material 120 in a cylindrical shape, but the shape of the load may be other than cylindrical as long as it can be suspended by a lifting machine. For example, the shape of the load may be cylindrical, or may be other than cylindrical or cylindrical. A cylindrical or cylindrical load has a property that when a measurement signal is irradiated to the circumferential surface, the signal strength of the reflected signal is likely to change depending on the direction of irradiation of the measurement signal. By utilizing this property, for a cylindrical or cylindrical load, it is possible to easily determine whether the reflected signal of the measurement signal irradiated to the load is a reflected signal reflected by the circumferential surface of the load or a reflected signal reflected by a marker part of a cushioning material on the load, using the received strength of the reflected signal as an index. In the embodiment, the case where the conveying device 1 as the lifting machine is an overhead crane has been described, but the lifting machine may be a crane other than an overhead crane, such as a gantry crane.

[0098] Although several embodiments have been described above, the embodiments can be modified or modified based on the above disclosure. All components of the above embodiments and all features described in the claims may be individually extracted and combined as long as they are not mutually inconsistent. [Explanation of symbols]

[0099] 1. Transport equipment (lifting machine) 4 Trolley 6a First sensor 6b Second sensor 8. Control and calculation unit (computer) 23 Acquisition Department 24 Specific part 25 Discrimination part 140 Cushioning material 150 Marker section C Coil (load) La laser (measurement signal) Pm measurement area Ps irradiation point

Claims

1. a determination unit that determines a measurement location where a plurality of reflected signals, which are respectively reflected in each irradiation direction of a plurality of measurement signals irradiated from different irradiation directions to a measurement location of a load on a floor on which the load suspended by a lifting machine is stacked, are received with a predetermined signal strength corresponding to the signal reflectivity of a retroreflective material in a marker portion on the surface of a cushioning material placed on the load on the floor; a discrimination unit that discriminates the cushioning material present at a position on the floor where the load is to be placed based on the measurement portion identified by the identification unit; A cushioning material detection device comprising:

2. 2. The cushioning material detection device according to claim 1, wherein the measurement portion includes a plurality of irradiation points to which the measurement signals are respectively irradiated, and the identification unit accumulates information on the signal strength in the irradiation direction of the reflected signals reflected at each of the plurality of irradiation points included in one of the measurement portions, and identifies the measurement portion at which a plurality of reflected signals within the measurement portion reflected in each irradiation direction are received at the predetermined signal strength based on the accumulated signal strength information.

3. The cushioning material detection device of claim 2, wherein the identification unit groups and stores information on the signal intensity of the reflected signals reflected at each of the multiple irradiation points included in one of the measurement sites, or stores the information in association with the measurement site including the multiple irradiation points, and identifies a measurement site from the accumulated signal intensity information at which multiple reflected signals within the measurement site reflected in each irradiation direction are received at the specified signal intensity.

4. a measurement portion identification unit which identifies a measurement portion of a load on a floor on which the load suspended by a lifting machine is stacked, the measurement portion being received at a predetermined signal strength corresponding to a signal reflectance of an anti-reflection material in a marker portion on the surface of a cushioning material placed on the load on the floor, the measurement signal being irradiated from a position directly facing the load on the floor and reflected in the irradiation direction of the measurement signal; a discrimination unit that discriminates the cushioning material present at a position on the floor where the load is to be placed based on the measurement portion identified by the identification unit; A cushioning material detection device comprising:

5. The cushioning material detection device according to claim 4, wherein the identification unit identifies a measurement location where the reflected signal corresponding to the measurement signal irradiated to the measurement location from a direction that forms an angle with a perpendicular to the surface of the load on the floor within a predetermined angle range is received with the predetermined signal strength.

6. A cushioning material detection device as described in any one of claims 1 to 5, further comprising an acquisition unit that acquires position information of the load on the floor, wherein the identification unit identifies a measurement location where the reflected signal is received at the specified signal strength within a detection range set based on the position information.

7. The identification unit identifies a measurement location among a plurality of areas obtained by dividing a plane parallel to the floor surface on which the load on the floor is placed in the direction of movement of the lifting machine, where the reflected signal of the measurement signal that has passed through the same area is received with the predetermined signal strength, and the discrimination unit discriminates the cushioning material present at a position on the floor where the load should be placed, based on the area identified as the measurement location where the reflected signal is received with the predetermined signal strength.

8. The cushioning material detection device according to claim 7, wherein the discrimination unit discriminates the cushioning material present at a position on the floor where the load should be placed based on the size of a group of areas in which an area identified as a measurement portion where the reflected signal is received at the specified signal strength is connected in the direction of movement.

9. A cushioning material detection device as described in any one of claims 1 to 5, wherein the load has a cylindrical or columnar outer shape, and the measurement signal is irradiated to the same measurement location while changing its position at least in the circumferential direction of the load.

10. A method for detecting a cushioning material using a computer having a calculation unit and an input / output unit, comprising: The calculation unit: Identifying a measurement portion where a plurality of reflected signals, which are respectively reflected in each irradiation direction of a plurality of measurement signals irradiated from mutually different irradiation directions onto a measurement portion of a load on a floor on which the load suspended by a lifting machine is stacked, are received with a predetermined signal strength corresponding to the signal reflectivity of a retroreflective material in a marker portion on the surface of a cushioning material placed on the load on the floor; Identifying the cushioning material present at a position on the floor where the load is to be placed based on the identified measurement portion. Cushioning material detection method.

11. A method for detecting a cushioning material using a computer having a calculation unit and an input / output unit, comprising: The calculation unit: a measurement portion on a load on a floor on which the load suspended by a lifting machine is stacked, the measurement portion being received with a predetermined signal strength corresponding to the signal reflectance of an anti-reflective material in a marker portion on the surface of a cushioning material placed on the load on the floor, the reflection signal being reflected in the direction of irradiation of the measurement signal, the measurement signal being irradiated from a position directly facing the load on the floor; Identifying the cushioning material present at a position on the floor where the load is to be placed based on the identified measurement portion. Cushioning material detection method.

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