JP6631023B2 - Image display device - Google Patents

Description

  The present invention relates to an image display device.

A camera for photographing an object below is attached to a crane boom or jib (hereinafter, referred to as a boom or the like). From a boom or the like, a hook is suspended by a wire rope, and a suspended load is slung on the hook. Then, the camera captures an image of a subject in which a wire rope, a hook, a suspended load, and the like are projected on a horizontal plane such as the ground surface.
An image captured by the camera is displayed on a monitor provided in an operator room where the operator operates the crane. The operator operates the crane while watching the image displayed on the monitor to move the suspended load to a desired place (for example, see Patent Document 1).

JP-A-6-30315

The operator of the crane adjusts the operation input to the operation unit while watching the movement of the hook displayed on the monitor.
However, since the camera is not installed directly above the hook, the wire rope that lifts the hook is projected on the display unit in an oblique direction. Moreover, since the hook is located at a position suspended from the ground surface, even if the hook is only moved up and down without moving the boom, the position of the hook displayed on the display unit is the background image such as the ground surface. To move against. Therefore, it is difficult for the operator to see only the image projected on the display unit and recognize the position where the hook descends (the projection point of the hook) on the ground surface or the like.
The present invention has been made in view of the above circumstances, and can make it easier for an operator to recognize the position of a projection point of a hook displayed on a display unit on a horizontal plane having a specific height such as the ground surface. It is an object to provide an image display device.

  The present invention is directed to a display unit that displays an image that is captured by a camera provided on a crane boom and includes a hook that is suspended from the boom by a wire rope, and a horizontal plane having a predetermined height of the hook. And a projection corresponding point calculation unit for obtaining a projection corresponding point displayed on the display unit corresponding to the projection point of (a), wherein the display unit specifies the projection corresponding point obtained by the projection corresponding point calculation unit. An image display device for displaying a mark to be displayed together with an image of the hook.

  ADVANTAGE OF THE INVENTION According to the image display apparatus which concerns on this invention, the position of the projection point on the horizontal surface of a specific height, such as a ground surface, of the hook displayed on the display part can be made easy for an operator to recognize.

It is a schematic diagram which shows the mode of the crane operation | work which moves a suspended load using a crane. It is a schematic diagram which shows an example of the image display apparatus installed in the operator room. FIG. 2 is a block diagram illustrating a configuration of the image display device according to the first embodiment. It is the figure which simplified the schematic diagram shown in FIG. FIG. 3 is a schematic diagram corresponding to FIG. 2 showing the position of a projection corresponding point. FIG. 3 is a schematic diagram corresponding to FIG. 2 displaying a mark for specifying a projection corresponding point. FIG. 9 is a block diagram illustrating a configuration of an image display device according to a second embodiment. FIG. 7 is a schematic diagram showing an example in which a mark for specifying a hook moving direction (hook descent) and a mark for specifying a projection corresponding point are displayed on a display panel. It is a schematic diagram which shows the example which displayed the mark which specifies the moving direction (hook rise) of a hook, and the mark which specifies a projection corresponding point on a display panel. It is a figure which shows the example of a display which displayed the character which shows the length on the ground surface which the arrow represents beside the arrow. FIG. 8 is a block diagram illustrating an image display device according to a third embodiment including a projection corresponding point calculation unit instead of the projection corresponding point calculation unit in the image display device illustrated in FIG. 7. FIG. 3 is a schematic diagram corresponding to FIG. 2 showing the position of a projection corresponding point.

Hereinafter, an embodiment of an image display device according to the present invention will be described with reference to the drawings.
[Embodiment 1]
<Crane operation>
FIG. 1 is a schematic diagram showing a state of a crane operation of moving a suspended load 700 using a crane 800 in which an upper swing body is installed on a lower traveling body. The crane 800 includes a boom 810 that expands, lowers, and turns, a hook 830 that moves up and down, and an operation unit 820 to which operations of expanding, lowering, turning, and turning the boom 810 and raising and lowering the hook 830 are input. A wire rope 840 wound up or down by a winch motor is wound around a sheave provided at the tip of the boom 810. A hook 830 on which the suspended load 700 is slung is suspended from the wire rope 840. Then, the suspended load 700 moves up and down together with the hook 830 by the operation of hoisting or lowering the wire rope 840 by the winch motor.

  In this specification, the term “boom” means an entire structure that is an arm with one end of the upper swing body as a fulcrum. Therefore, the “boom” in the present specification includes a lattice structure jib and an auxiliary jib for extending the boom, in addition to a boom that is a box-shaped structure jib.

Extending and retracting, raising and lowering and turning of the boom 810, and lifting and lowering of the hook 830 are performed by an operator of the crane 800 inputting an operation to an operation unit 820 provided in an operator room 850.
Specifically, operation unit 820 outputs an operation signal S corresponding to the input operation. The operation signal S output from the operation unit 820 controls operations of a hydraulic pump, a direction control valve, a flow control valve, and the like. The hydraulic pump, the direction control valve, the flow control valve, and the like operate the hydraulic motor and the hydraulic cylinder to extend and retract the boom 810, raise and lower the swing, and raise and lower the hook 830.

  Then, the length L, the elevation angle α, and the turning angle β of the boom 810 whose state has changed based on the operation signal S are respectively detected by sensors, and boom provided in the operator room 850 as information on the state of the boom 810. The information is input to the state information unit 200 (see FIG. 3 described later).

In addition, a surveillance camera 300 that captures an image of a lower subject including the hook 830 is provided at the tip of the boom 810. The shooting range of the monitoring camera 300 is, for example, a range indicated by a broken line in FIG.
FIG. 2 is a schematic diagram illustrating an example of the image display device 100 installed in the operator room 850. The image P captured by the monitoring camera 300 is displayed on the display panel 12 of the image display device 100 shown in FIG. Surveillance camera 300 is installed at a position shifted from the vertical line of hook 830. Therefore, on the display panel 12, the image 840A of the wire rope 840 in the image P is displayed as an image 840A extending obliquely from the outside of the display panel 12.
The monitoring camera 300 is set so that the optical axis extends in the vertical direction, and the optical axis of the monitoring camera 300 and the wire rope 840 are apart from each other by, for example, a distance D1 on a horizontal plane.

<Image display device>
FIG. 3 is a block diagram illustrating a configuration of the image display device 100 according to the first embodiment of the present invention. As shown in FIG. 3, the image display device 100 includes a display unit 10 and a projection corresponding point calculation unit 40.
The display unit 10 includes a display control unit 11 that processes contents to be displayed based on the input information, and a display panel 12 that displays an image P corresponding to the contents processed by the display control unit 11. Then, the display control unit 11 receives the image P captured by the monitoring camera 300 as described above, processes the image P to be displayed on the display panel 12, and the display panel 12 displays the processed image P. I do. The image P also includes an image 830A of the hook 830.

The projection corresponding point calculation unit 40 projects the hook 830 onto the ground surface H0 (an example of a preset horizontal plane) based on the length L and the elevation angle α of the boom 810 input from the boom state information unit 200. A projection corresponding point MA corresponding to the point M and displayed on the display panel 12 is obtained.
Here, the calculation of the projection corresponding point MA will be described below with reference to FIGS. 4 is a simplified diagram of the schematic diagram shown in FIG. 1, FIG. 5 is a schematic diagram corresponding to FIG. 2 showing the position of the projection corresponding point MA, and FIG. It is the schematic diagram corresponding to FIG. 2 displayed.

When the winch motor is operated from the state shown in FIG. 4 to lower the hook 830, the hook 830 descends vertically and reaches the ground surface H0. The position of the hook 830 that has reached the ground surface H0 is the projection point M of the hook 830. The projection corresponding point MA means an image of the projection point M in the image P displayed on the display panel 12.
Since the optical axis of the surveillance camera 300 and the wire rope 840 are separated on the horizontal plane by, for example, the distance D1, as shown in FIG. 5, an image 840A of the wire rope 840 displayed on the display panel 12 is displayed on the display panel 12 Is an image 840A that extends diagonally from the outside of the image. When the hook 830 is lowered, the image 830A of the hook 830 in the image P displayed on the display panel 12 is lowered along the image 840A of the wire rope 840.

The projection corresponding point MA corresponding to the projection point M when the hook 830 reaches the ground surface H0 exists on an extension of the image 840A of the wire rope 840.
As shown in FIG. 4, the boom 810 is installed on a lower structure having a predetermined height (ground height) h0 from the ground surface H0. When the length L of the boom 810 is equal to the elevation angle α, the distance (height) H from the tip of the boom 810 to the ground surface H0 is calculated by the following equation (1).
H = L × sin α + h0 (1)

Further, assuming that the angle of view of the monitoring camera 300 is θ, the shooting width D on the ground surface H0 captured by the monitoring camera 300 is calculated by the following equation (2).
D = {H × tan (θ / 2)} × 2 (2)
Here, assuming that the center position of the photographing width D (the intersection between the optical axis of the monitoring camera 300 and the ground surface H0) is O, the distance between the optical axis of the monitoring camera 300 and the wire rope 840 in the horizontal plane is D1. The projection point M on the ground surface H0 is located at a distance D1 from the center position O of the shooting width D.

Assuming that the center position of the display panel 12 corresponding to the center position O is o as shown in FIG. 5 and that the ratio of the size of the display panel 12 to the shooting width D (display ratio) is K, the distance D1 from the center position O is D1. The distance D1A from the center position o of the projection corresponding point MA corresponding to the projection point M that is only a distance away is calculated by the following equation (3).
D1A = D1 × K (3)
Therefore, the projection corresponding point MA in the image P of the display panel 12 is located at the distance D1A calculated from the center position o of the display panel 12 by the formulas (1) to (3) and the image 840A of the wire rope 840. It is required that the position be on the extension line 840V.

  Note that the ground height h0 up to the fulcrum of the boom 810, the angle of view θ of the surveillance camera 300, and the display ratio K are constant regardless of the state of the boom 810 and are preset values. It is stored in the projection corresponding point calculation unit 40 in advance. Then, the projection corresponding point calculation unit 40 calculates the expressions (1) to (3) based on the length L and the elevation angle α of the boom 810 input from the boom state information unit 200 and the above-described values stored in advance. ), The position of the projection corresponding point MA is obtained, and the obtained position of the projection corresponding point MA is output to the display control unit 11.

As illustrated in FIG. 6, the display control unit 11 places a mark 600 (for example, a black circle) for specifying the projection corresponding point MA at the position of the projection corresponding point MA of the hook 830 input from the projection corresponding point calculation unit 40. Generate. Then, the display panel 12 displays the mark 600 generated by the display control unit 11 so as to be superimposed on the image P including the image 830A of the hook 830.
In addition, in FIG. 6, under the control of the display control unit 11, the extension line 840V of the image 840A of the wire rope 840 extending to the projection corresponding point MA is displayed together with the projection corresponding point MA. It is not necessary to display the extension line 840V. When the extension line 840V is displayed, the operator can recognize the approximate height from the ground surface H0 to the current position of the hook 830 based on the length of the extension line 840V.
Note that the form of the mark 600 can be various forms such as a white circle and an X, in addition to the black circle described above, and is not limited to the black circle.

According to the image display device 100 configured as described above, the projection corresponding point MA of the hook 830 displayed on the display panel 12 corresponding to the projection point M on the ground surface H0 is displayed by the mark 600. The operator who operates the crane 800 while viewing the image P displayed on the panel 12 can easily recognize the position of the projection point M.
Note that the projection corresponding point calculation unit 40 calculates the position of the projection corresponding point MA based on the calculations of Expressions (1) to (3). The calculation is not limited to (3). That is, the specific content of the arithmetic expression is determined according to the installation position of the monitoring camera 300, the positional relationship with the wire rope 840, and the like. Therefore, the specific content of the arithmetic expression is determined according to these aspects. .

[Embodiment 2]
The image display apparatus 100 according to the first embodiment displays the projection corresponding point MA corresponding to the projection point M of the hook 830 on the ground surface H0 on the display panel 12, but in addition to the projection corresponding point MA, A mark 500 that specifies the direction in which the projection corresponding point MA moves, which corresponds to the movement of the hook 830 due to the operation input to the operation unit 820 of the crane 800, may also be displayed.

FIG. 7 is a block diagram illustrating a configuration of the image display device 110 according to the second embodiment of the present invention. As shown in FIG. 7, the image display device 110 includes an operation signal acquisition unit 20 and a movement direction calculation unit 30 in addition to the display unit 10 and the projection corresponding point calculation unit 40 described above.
The operation signal acquisition unit 20 acquires an operation signal S output by an operation input to the operation unit 820 so as to move the hook 830. The movement direction calculation unit 30 determines the movement direction of the hook 830 (on the horizontal plane) on a horizontal plane such as the ground surface H0 based on the operation signal S acquired by the operation signal acquisition unit 20.

Here, the crane 800 and other machines have a so-called dead zone in which the hook 830 does not actually start moving even when an operation is input to the operation unit 820. This dead zone occurs for the following reason, for example. That is, the operation unit 820 detects an input operation and outputs an operation signal S corresponding to the detected operation. However, when the hydraulic pressure generated by the hydraulic pump or the like according to the opening of the flow control valve or the direction control valve by the operation signal S is smaller than the load of the suspended load 700, the hook 830 does not start moving.
Therefore, the dead zone mainly occurs in a range where the operation input to the operation unit 820 is small. Then, the hook 830 actually starts to move by the input of the operation having the size exceeding the dead zone.
The operation signal acquisition unit 20 of the image display device 100 acquires at least the operation signal S in the above-described dead band.

  As described above, in the operation in the dead zone, the hook 830 does not actually start to move, so that the moving direction of the hook 830 does not exist. However, even if the input operation signal S is the operation signal S corresponding to the above-mentioned dead zone, the moving direction calculation unit 30 assumes that there is no load and the hook 830 moves with respect to the horizontal plane. Find the direction of the wax movement.

The movement direction of the hook 830 on the horizontal plane calculated by the movement direction calculation unit 30 is input to the display control unit 11 of the display unit 10.
Here, the direction in which the projection point M of the hook 830 moves as the hook 830 moves corresponds to the direction in which the hook 830 moves. Then, the moving direction of the projection corresponding point MA displayed on the display panel 12 matches the moving direction of the image 830A of the hook 830.
Therefore, the display control unit 11 uses the moving direction of the image 830A of the hook 830 as the moving direction of the projection corresponding point MA. That is, the display control unit 11 determines the display panel 12 based on the movement direction of the hook 830 on the horizontal plane input from the movement direction calculation unit 30 and the projection corresponding point MA calculated by the projection corresponding point calculation unit 40. Is generated, a mark 500 (see FIG. 8 described later) for specifying the moving direction corresponding to the projection corresponding point MA displayed in. Then, the display panel 12 displays the mark 500 generated by the display control unit 11 so as to be superimposed on the image P including the projection corresponding point MA.

  8 and 9 are schematic diagrams illustrating an example in which a mark 500 for specifying the moving direction of the hook 830 and a mark 600 for specifying the projection corresponding point MA are displayed on the display panel 12. Note that, in the display example shown in FIG. 8, an X mark is displayed as the mark 500z for specifying the lowering (moving downward) of the hook 830 due to the lowering (unwinding) of the wire rope 840. In the display example shown in FIG. 9, a mark ｚ is displayed as a mark 500z that specifies the rise (movement upward) of the hook 830 due to the winding of the wire rope 840.

  In the examples shown in FIGS. 8 and 9, the movement direction calculation unit 30 determines whether the movement direction of the hook 830 on the horizontal plane is the expansion and contraction and the undulation of the boom 810. The same applies to the following.) The radial movement of the hook 830 on the horizontal plane and the turning of the boom 810 (because of the dead zone, it is not necessary to actually turn the hook. The operation is divided into the movement of the hook 830 in the turning direction on the horizontal plane and the movement of the hook 830 in the ascending or descending direction due to the elevation.

Then, the display control unit 11 makes the mark 500 displayed on the display panel 12 correspond to the projection corresponding point MA displayed on the display panel 12 based on the radial movement input from the movement direction calculation unit 30. Based on the arrow 500y along the radial direction (vertical direction y of the display panel 12) and the movement in the turning direction input from the moving direction calculation unit 30, it is made to correspond to the projection corresponding point MA displayed on the display panel 12. An arrow 500x along the turning direction (horizontal direction x of the display panel 12) and a mark 500z indicating whether to rise or fall along the image 840A of the wire rope 840 are generated.
Each of the arrows 500x and 500y is generated such that the tips of the arrows 500x and 500y coincide with the moving direction. The mark 500z is generated as a cross when the hook 830 is lowered, and a circle when the hook 830 is raised.

In addition, the display control unit 11 generates the arrows 500y and 500x by associating each start point of the two arrows 500y and 500x with the position of the projection corresponding point MA in the image P displayed on the display panel 12. The display control unit 11 generates a mark 500z specifying the lowering or rising of the hook 830 by superimposing the mark 500z specifying the projection corresponding point MA displayed on the display panel 12.
As shown in FIGS. 8 and 9, the display panel 12 has two arrows 500x and 500y as marks 500 for specifying the direction in which the hook 830 moves, and the starting points of the arrows 500x and 500y correspond to the image 830A of the hook 830. And display it.
Note that the position of the projection corresponding point MA on the image P displayed on the display panel 12 is calculated by the projection corresponding point calculation unit 40 and input to the display control unit 11.

  According to the image display device 110 configured as described above, when an operation is input to the operation unit 820, the hook 830 is displayed together with the mark 600 specifying the projection corresponding point MA from a stage before the hook 830 actually starts moving. Arrows 500y, 500x and a mark 500z indicating the moving direction in which the (projected corresponding point MA) is about to move are displayed on the display panel 12. Therefore, according to the image display device 100 of the present embodiment, the operator can visually recognize the arrows 500y, 500x and the mark 500z displayed on the display panel 12, thereby instantly recognizing the moving direction of the projection corresponding point MA. Can be done.

Further, according to the image display device 110 of the present embodiment, the movement direction of the hook 830 is indicated by the arrows 500x and 500y corresponding to the components in the two directions, so that at least one of the expansion and contraction and the undulation of the boom 810 can be performed. The operator can recognize whether or not the operation of turning the boom 810 is performed simultaneously (combined operation is performed).
Note that an arrow 500y indicates that the operation of performing the sole operation of extending and retracting the boom 810 or the operation of performing the single operation of raising and lowering the boom 810 is performed at the same time (combined operation is performed), and the turning operation is performed. This is displayed when the working radius of the hook 830 from the center changes.

Further, when the moving direction calculation unit 30 determines that the input operation signal S is an operation signal for actually moving the hook 830 (an operation signal exceeding the dead band), the image display device 110 displays the display control unit 11. However, the mark 500 for specifying the moving direction of the projection corresponding point MA may not be displayed on the display panel 12.
In this case, after the boom 810 exits the dead zone and the hook 830 actually starts moving, the mark 500 for specifying the moving direction is not displayed on the display panel 12 so that the hook 830 is moved in the moving direction of the projection corresponding point MA. It is possible to prevent the background image from being hidden by the mark 500 that specifies the moving direction.

  On the other hand, when the input operation signal S is an operation signal corresponding to the combined operation of extending and retracting the boom 810 and undulating, the radius of the projection point M of the hook 830 on the ground surface H0 with respect to the turning center is determined. When the moving direction calculation unit 30 determines that the movement is changed by the combined operation, the display control unit 11 determines the radial moving direction of the projection corresponding point MA regardless of whether the boom 810 is in the dead zone. When the moving direction calculating unit 30 determines that the radius does not change due to the composite operation, the display control unit 11 does not display the mark 500 that specifies the radial moving direction of the projection corresponding point MA. It may be.

  When the operator inputs an operation to the operation unit 820 so as to perform a composite operation, the operator intuitively understands the correspondence between the content of the input operation and the actual moving direction of the projection point M of the hook 830. May be difficult to recognize. However, in the case of a composite operation in which the radius of the projection point M of the hook 830 changes, the image display device 110 displays the movement direction with arrows 500x and 500y before the projection point M of the hook 830 actually starts moving. The operator can be informed in advance that the movement will change the radius, so that the operator can draw attention to the positional relationship between the projection corresponding point MA of the hook 830 and the surroundings.

  The image display device 110 of the present embodiment applies the arrows 500x and 500y as the marks 500 for specifying the moving direction of the projection corresponding point MA of the hook 830. The lengths of the arrows 500x and 500y on the display panel 12 are as follows. It may be formed to have a predetermined length representing a predetermined length (for example, length 1 [m]) on the ground surface H0.

  As described above, the lengths of the arrows 500x and 500y shown on the display panel 12 correspond to the fixed lengths on the ground surface H0, so that the distance between the projection corresponding point MA moving on the ground surface H0 and the surroundings can be felt. Also, it is possible to make it easy for the operator to recognize the size of a surrounding object (such as an obstacle).

Further, the display control unit 11 may cause a character indicating the length on the ground surface H0 represented by the arrows 500x and 500y to be displayed beside the arrows 500x and 500y displayed on the display panel 12.
FIG. 10 is a display example in which a character indicating the length on the ground surface H0 indicated by the arrow 500y (for example, a character “1m” indicating a length of 1 [m]) is displayed beside one arrow 500y. FIG.
In this way, by displaying characters indicating the length of the arrow 500y on the ground surface H0 together with the display panel 12, it is possible to provide the operator with specific information regarding a sense of distance and size.

The display control unit 11 determines whether or not to display the above-described arrows 500x and 500y corresponding to a predetermined length on the ground surface H0 based on the zoom magnification of the monitoring camera 300 and the ground clearance of the hook 830. It can be set accordingly.
For example, when the zoom magnification of the surveillance camera 300 is large, the arrows 500x and 500y indicating the predetermined lengths may become too large and protrude from the display panel 12. In this case, by making the display of the arrows 500x and 500y smaller than the predetermined length on the ground surface H0, the entirety of the arrows 500x and 500y can be displayed on the display panel 12.

  On the other hand, when the zoom magnification of the monitoring camera 300 is small, the arrows 500x and 500y indicating the predetermined length may be too small to be visually recognized. In this case, the display of the arrows 500x and 500y on the display panel 12 can be made easier to see by making the display of the arrows 500x and 500y longer than a predetermined length on the ground surface H0.

In addition, the height of the hook 830 can be detected by, for example, the moving direction calculation unit 30 by detecting the extension length of the wire rope 840 hanging the hook 830. The extension length of the wire rope 840 can also be indirectly detected according to the rotation amount of a winch motor that winds and unwinds the wire rope 840.
Then, for example, when the height of the hook 830 is high (for example, when the ground height is about 50 [m]), the lengths of the arrows 500x and 500y are displayed on the ground surface H0 in correspondence with the length 1 [m]. Even so, it is possible that the length of the display becomes too short to make it difficult to visually recognize. In this case, the display of the arrows 500x and 500y on the display panel 12 can be made easier to see by making the display of the arrows 500x and 500y longer than a predetermined length on the ground surface H0.

  On the other hand, when the height of the hook 830 is low (for example, at a height of about 1 [m] above the ground), it is assumed that the hook 830 is approaching the suspended load 700 arranged on the ground surface H0. In this case, it may not be necessary to display the arrows 500x and 500y themselves. In this case, by making the sizes of the arrows 500x and 500y smaller than the predetermined length on the ground surface H0, it is possible to prevent the image of the suspended load 700 from being blocked by the arrows 500x and 500y.

[Embodiment 3]
Embodiments 1 and 2 described above show examples in which the projection point M of the hook 830 is a projection point on the ground surface H0. However, the image display device according to the present invention is not limited to the projection point of the hook on the ground surface. That is, the image display device of the present invention sets the projection point of the hook as the projection point M1 from the ground surface H0 to the horizontal plane Hh at a height (ground height) h as shown in FIG. 4, and corresponds to the projection point M1. The mark 610 for specifying the projection corresponding point M1A displayed on the display panel 12 may be displayed together with the image 830A of the hook 830.

Specifically, the projection corresponding point calculation unit of the image display device calculates the position of the projection corresponding point M1A displayed on the display panel 12 corresponding to the projection point M1 of the hook 830 on the horizontal plane Hh at the ground height h. do it.
FIG. 11 is a block diagram showing an image display device 120 including a projection corresponding point calculation unit 41 instead of the projection corresponding point calculation unit 40 in the image display device 110 shown in FIG. The image display device 120 is an embodiment of the image display device according to the present invention.

Here, the projection corresponding point calculation unit 41 uses the hook L based on the length L and the elevation angle α of the boom 810 input from the boom state information unit 200 and the ground height h input to the height input unit 210. The position of the projection corresponding point M1A displayed on the display panel 12 corresponding to the projection point M1 on the horizontal plane Hh (an example of a preset horizontal plane) at the ground height h is obtained.
Specifically, when the length L of the boom 810 is equal to the elevation angle α, the distance (height) H ′ from the tip of the boom 810 to the horizontal plane Hh at the ground height h is calculated by the above equation (4).
H ′ = H−h (4)
However, the height H is based on equation (1).

Further, assuming that the angle of view of the monitoring camera 300 is θ, the shooting width D ′ on the horizontal plane Hh at the ground height h captured by the monitoring camera 300 is calculated by the following equation (5).
D ′ = {H ′ × tan (θ / 2)} × 2 (5)
Here, assuming that the center position of the photographing width D '(intersection between the optical axis of the monitoring camera 300 and the horizontal plane Hh) is O', the projection point M1 on the horizontal plane Hh is a distance D1 from the center position O 'of the photographing width D'. It will be just a distance away.

FIG. 12 is a schematic diagram corresponding to FIG. 2 showing the position of the projection corresponding point M1A and the mark 610. Assuming that the ratio of the size of the display panel 12 to the photographing width D '(display ratio) is K', as shown in FIG. 12, the projection corresponding point M1A corresponding to the projection point M1 separated from the center position O 'by a distance D1. The distance D1A 'from the center position o is calculated by the following equation (6).
D1A ′ = D1 × K ′ (6)
Therefore, the projection corresponding point M1A in the image P of the display panel 12 is located at the position of the distance D1A 'calculated from the center position o of the display panel 12 by the equations (1), (4) to (6), and the wire rope. The position of the image 840 on the extension line 840V of the image 840A is required.

  Note that the ground height h0 up to the fulcrum of the boom 810, the angle of view θ of the surveillance camera 300, and the display ratio K are constant regardless of the state of the boom 810 and are preset values. It is stored in the projection corresponding point calculation unit 41 in advance. Then, the projection corresponding point calculation unit 41 calculates the length L and the elevation angle α of the boom 810 input from the boom state information unit 200, the ground height h input to the height input unit 210, and Based on the values, the position of the projection corresponding point M1A is obtained according to the equations (1), (4) to (6), and the obtained position of the projection corresponding point M1A is output to the display control unit 11.

  The display control unit 11 generates a mark 610 (for example, a cross) for specifying the projection corresponding point M1A at the position of the projection corresponding point M1A of the hook 830 input from the projection corresponding point calculation unit 41. Then, as shown in FIG. 12, the display panel 12 displays the mark 610 generated by the display control unit 11 so as to be superimposed on the image P including the image 830A of the hook 830.

According to the image display device 120 configured as described above, the projection corresponding point M1A corresponding to the projection point M1 of the hook 830 on the horizontal plane Hh at the ground height h can be displayed on the display panel 12.
Accordingly, even when the hook 830 is dropped on, for example, the roof of a building with a ground height h, the projection corresponding point M1A corresponding to the projection point M1 on the roof or the like is displayed with the mark 600, so that it is displayed on the display panel 12. The operator who operates the crane 800 while viewing the image P can easily recognize the position of the projection point M1.

  Note that the projection corresponding point calculation unit 40 calculates the position of the projection corresponding point MA on the ground surface H0, whereas the projection corresponding point calculation unit 41 calculates the position of the projection corresponding point M1A on the horizontal plane at the ground height h. Otherwise, the configuration is the same as that of the projection corresponding point calculation unit 40. By setting the ground height h = 0, the projection corresponding point calculation unit 41 can also calculate the position of the projection corresponding point MA on the ground surface H0, similarly to the projection corresponding point calculation unit 40.

Reference Signs List 10 display unit 11 display control unit 12 display panel 20 operation signal acquisition unit 30 moving direction calculation unit 40 projection corresponding point calculation unit 100 image display device 300 monitoring camera 800 crane 810 boom 820 operation unit 830 hook 840 wire rope

Claims (4)

A display unit that displays an image captured by a camera provided on a crane boom and that includes a hook suspended from the boom by a wire rope;
A projection corresponding point calculation unit that obtains a projection corresponding point displayed on the display unit, corresponding to a projection point on a horizontal plane having a preset height of the hook,
An operation signal acquisition unit that acquires an operation signal are output in correspondence with the operation, which is input to the operation portion so that moving the hook,
A moving direction calculating unit that obtains a moving direction of the hook in a horizontal plane based on the operation signal acquired by the operation signal acquiring unit, by an operation input to the operating unit,
The display unit displays a mark identifying the projection corresponding point obtained by the projection corresponding point calculation unit together with the hook image,
The operation signal operation signal acquisition unit has acquired, entering the operation to the operation section-out preparative operation signal corresponding to the dead zone in which the hook does not start actually move, the display unit, the moving direction A mark that specifies the moving direction of the hook determined by the calculating unit as the moving direction of the projection corresponding point is displayed together with a mark that specifies the projection corresponding point,
Operating signals the operating signal acquisition unit has acquired, corresponding to the operation of the size exceeds the deadband, when pre SL is an operation signal to actually move the hook, the display unit, of the projection corresponding point An image display device that does not display a mark that specifies a moving direction. The image display device according to claim 1 , wherein a length of a mark, which is displayed on the display unit and specifies a moving direction of the projection corresponding point, represents a certain length corresponding to a predetermined length on the horizontal plane. . The image display device according to claim 2, wherein the display unit displays a character representing the predetermined length beside a mark that specifies a moving direction of the projection corresponding point. The projection corresponding point calculation unit, depending on the height of the expansion state and relief conditions and the horizontal plane of the boom, the image display apparatus according to any one of claims 1 or al 3 for obtaining the projection corresponding point .