JP2014227246A - Working area line display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working area line display device which can display a working area line at a correct position even without providing a fluctuation detection device.SOLUTION: A working area line display device 100 comprises a monitor camera 32 which is provided at the tip part 16Ca of the tip boom 16C of the telescopic boom 16 of a crane and is faced downward, and a monitor 70 which superimposes a working area line showing an area in which a load hung by a hook is movable on an image imaged by the monitor camera 32. Further provided are a pan switch SW1 and a tilt switch SW2 which operate a camera attitude so as to position the hook imaged by the monitor camera 32 at a specified position on a screen, and an attitude angle calculation part 63 which determines the attitude angle of the monitor camera 32 based on position information of the hook and position information of the tip part 16Ca of the telescopic boom 16. The correct position of the working area line on the image of the monitor 70 is determined corresponding to the attitude angle of the monitor camera 32 determined by the attitude angle calculation part 63, and the working area line is displayed at the determined position.

Description

  The present invention relates to a work area line display device that superimposes and displays a work area line on an image captured by a camera.

  2. Description of the Related Art Conventionally, a crane surveillance camera device in which a TV camera is provided at the tip of a boom is known (see Patent Document 1).

  Such a crane surveillance camera device is provided with a camera housing at the tip of a boom, a TV camera is provided in the camera housing so as to be able to swing downward and swing, and the TV camera is swung in the left-right direction and the front-rear direction 2. By providing two motors and swinging the TV camera left and right and back and forth with these two motors, a wide area around the hook is photographed and displayed on the monitor, thereby improving the safety of crane operations. Is.

  However, in such a crane surveillance camera device, there is a problem that it is not known to which range the suspended load may be moved.

  Therefore, it has been proposed to superimpose and display a work area line indicating an area where the suspended load can be moved on the monitor screen.

Japanese Patent Laid-Open No. 6-24680

  However, in order to always display the work area line at the correct position on the captured image regardless of the left / right or front / rear swing angle of the TV camera, the swing angle detection that detects the front / rear / left / right swing of the TV camera. It is necessary to provide a device and display the work area line at the correct position on the image according to the swing angle from the swing angle detected by the swing angle detecting device.

  However, when the swing angle detecting device is provided, there is a problem that the crane camera device becomes expensive.

  An object of the present invention is to provide a work area line display device capable of displaying a work area line at a correct position without providing a swing angle detecting device.

According to the first aspect of the present invention, there is provided a camera which is provided at the tip of the boom of the working machine and is directed downward, and an operation indicating a movable region of a suspended load suspended by a hook on an image captured by the camera. A work area line display device comprising a monitor for superimposing and displaying area lines,
Posture operation means for operating the posture of the camera so that the hook imaged by the camera is positioned at a predetermined position on the screen;
Calculating means for determining the posture angle of the camera based on the position information of the hook and the position information of the boom tip;
A correct position of the work area line on the image is obtained according to the attitude angle of the camera obtained by the calculating means, and the work area line is displayed at the obtained position.

  According to the present invention, the work area line can be displayed at a correct position without providing a swing angle detecting device for detecting the swing angle of the camera.

It is the side view which showed the mobile crane carrying the working area line display apparatus which concerns on this invention. It is the block diagram which showed roughly the structure of the control system of a working area line display apparatus. It is explanatory drawing which showed an example of the monitor screen of a work area line display apparatus. FIG. 4 is a block diagram illustrating a configuration of the image processing controller illustrated in FIG. 3. It is explanatory drawing which showed the principle which calculates | requires an action | operation area | region line geometrically. It is explanatory drawing which showed that an offset changes with the undulation angles of an expansion-contraction boom. It is explanatory drawing which showed that the inclination | tilt angle of a surveillance camera was constant irrespective of the undulation angle of an expansion-contraction boom, when the rotating shaft of a surveillance camera and the center of a sheave correspond. It is explanatory drawing which displayed the frame, the hook image, and the work area line on the monitor screen. It is the block diagram which showed the structure of the working area line display apparatus of 2nd Example. It is the block diagram which showed the structure of the controller of the working area line display apparatus of 2nd Example. It is the block diagram which showed the structure of the working area line display apparatus of 3rd Example. It is the block diagram which showed the structure of the working area line display apparatus of 4th Example. It is the block diagram which showed the structure of the working area line display apparatus of 5th Example. It is explanatory drawing which showed the monitor screen of the working area line display apparatus of 5th Example. It is explanatory drawing which showed the monitor screen of the other example.

  Hereinafter, an embodiment which is an embodiment of a work area line display device according to the present invention will be described with reference to the drawings.

[First embodiment]
FIG. 1 shows a rough terrain crane 10 as a crane (work vehicle) which is a work machine equipped with a work area line display device. The rough terrain crane 10 (hereinafter referred to as a crane) includes a carrier 11 serving as a main body portion of a vehicle having a traveling function, a pair of left and right front outriggers 12 provided on the front side of the carrier 11, and a rear side of the carrier 11. A pair of left and right rear outriggers 13 provided on the upper side of the carrier 11, a swivel base 14 attached to the top of the carrier 11, a cabin 20 provided on the swivel base 14, and a bracket 15 fixed to the swivel base 14. And a telescopic boom 16 attached thereto.

  The telescopic boom 16 has a base end attached via a support shaft 17 and can be raised and lowered around the support shaft 17. A hoisting cylinder 18 is interposed between the bracket 15 and the telescopic boom 16, and the telescopic boom 16 is hoisted by expansion and contraction of the hoisting cylinder 18.

  The telescopic boom 16 has a base boom 16A, an intermediate boom 16B, and a tip boom 16C, and is configured to be nested in the base boom 16A in this order from the outside to the inside. The telescopic boom 16 is expanded and contracted by an expansion cylinder (not shown).

  A sheave (not shown) is provided at the distal end portion of the distal end boom 16 </ b> C. A wire rope 25 (hereinafter referred to as a wire) is hung on the sheave, and the hook block 19 is suspended by the wire 25. A hook 21 is attached to the hook block 19.

  The wire 25 is wound or sent out by a winch (not shown).

A monitoring camera device 30 is attached to the distal end portion of the distal end boom 16C.
The surveillance camera device 30 includes a housing 31 attached to the distal end portion of the tip boom 16C via a damper so as to always face downward due to its own weight, and a TV provided in the housing 31 so as to be tiltable in the pan direction and the tilt direction. A surveillance camera (camera) 32 such as a camera, a pan motor 33 (see FIG. 2) that tilts the surveillance camera 32 in the pan direction, a tilt motor 34 (see FIG. 2) that tilts the surveillance camera 32 in the tilt direction, and the like. Have.

  The tilt (orientation) of the surveillance camera 32 is operated by a pan switch (posture operation means) SW1 (see FIG. 2) and a tilt switch SW2 (posture operation means) (see FIG. 2) of an operation unit (not shown) provided in the cabin 20. This is done by the operation of (see).

  FIG. 2 is a block diagram showing a configuration of the work area line display device 100.

  The work area line display device 100 includes a monitoring camera device 30 provided at the tip of the telescopic boom 16, a boom posture detection sensor 50 that detects the posture of the telescopic boom 16, a detection signal detected by the boom posture detection sensor 50, and the like. And a monitor 70 that displays the image captured by the monitoring camera device 30 and the work area line obtained by the controller 60.

  On the screen 70G of the monitor 70, as shown in FIG. 3, a square frame M1 is displayed at the center of the screen.

  The boom posture detection sensor 50 detects a winch feed amount, a length of the telescopic boom 16, an elevation angle, a turning angle of the telescopic boom 16, and has sensors (not shown) for detecting each. Yes.

As shown in FIG. 4, the controller 60 includes a motor control unit 61 that drives and controls the pan motor 33 and the tilt motor 34 based on the operation of the pan switch SW1 and the tilt switch SW2, and a winch output from the boom posture detection sensor 50. A posture angle calculation unit (calculation means) 63 for calculating a posture angle of the surveillance camera 32 based on the feed amount, the length of the telescopic boom 16 and an offset W1 described later, and the posture angle and boom calculated by the posture angle calculation unit 63 Coordinates for obtaining the coordinate position of the crane coordinate system at each position on the imaged image with the turning center position of the telescopic boom 16 as the origin based on various detection signals of the telescopic boom 16 output from the posture detection sensor 50 A position calculation unit (coordinate position calculation means) 64 and a work area line indicating a movable area of the suspended load based on the load of the suspended load are obtained. The work area calculation unit (work area calculation means) 65 and the work area line obtained by the work area calculation unit 65 are combined on the image captured by the monitoring camera 32 in correspondence with the coordinate position calculated by the coordinate position calculation unit 64. Image synthesizing unit 66.
[Principle]
As shown in FIG. 5, it is assumed that the rotation axis 32J of the monitoring camera 32 and the center D1 of the sheave have an offset of W1 in the left-right direction (when the offset W2 in the vertical direction can be ignored). The height from the ground to the center D1 of the sheave is H1, the length from the center D1 of the sheave to the hook block 19 is L1, and the inclination of the monitoring camera 32 when the optical axis of the monitoring camera 32 is directed to the hook 21, That is, the inclination angle θ of the monitoring camera 32 with respect to the vertical line when the optical axis of the monitoring camera 32 is directed to the hook 21 is set. Then, the working radius of the telescopic boom 16 from the turning center position O of the telescopic boom 16 is R, and the distance between the work position R and the position P on the ground that is the center of the image when the surveillance camera 32 is tilted. Assuming ΔR, the distance ΔR can be obtained by the following equation.

ΔR = H1tanθ-W1
The inclination θ of the monitoring camera 32 can be obtained from the length L1 and the offset W1. The length L1 is obtained from the feed amount of the wire 25. The tilt of the surveillance camera 32 in the pan direction is obtained in the same manner.
The height H1 can be obtained from the length of the telescopic boom 16 and the undulation angle. The offset W1 can be determined according to the undulation angle of the telescopic boom 16 since the camera rotation shaft 32J with respect to the telescopic boom 16 and the position of the center D1 of the sheave are known.

  If the position on the ground corresponding to the center position of the monitor 70 (the center position of the image) is P, the turning center position O of the telescopic boom 16 can be obtained from the position P by the error ΔR and the work radius R. Similarly, the turning center position O is obtained with respect to the pan direction.

  A work area line can be drawn at a distance R1 (distance indicating the work area range) with the turning center position O as the center.

Here, since the center position of the image indicates the position P on the ground and the height H1 is known, the ground coordinate position and the coordinate position on the image can be associated with each other. That is, with the turning center position of the telescopic boom 16 as the origin, the coordinate position of the crane coordinate system is associated with each position on the captured image.
Thereby, the work area line can be superimposed on the correct position on the image and displayed on the monitor 70.
As shown in FIG. 5A, an offset W2 is also generated in the vertical direction depending on the undulation angle of the telescopic boom 16. Since the offset W2 can also be obtained from the undulation angle, the inclination of the surveillance camera 32 is obtained geometrically. Can do.
That is, ΔR = H1′tan θ−W1 and H1 ′ = H1−W2 are established.

From this equation, the inclination θ of the surveillance camera 32 can be obtained from the length L1 and the offsets W1 and W2. The tilt of the surveillance camera 32 in the pan direction is obtained in the same manner.
Further, as shown in FIG. 5B, when the rotation axis of the monitoring camera 32 is provided coaxially with the rotation axis of the sheave, when the optical axis of the monitoring camera 32 is directed to the hook 21, the optical axis of the monitoring camera 32 is tilted. Since it always faces directly below the direction, only the tilt angle in the pan direction needs to be obtained.
[Operation]
Next, the operation of the work area line display device 100 configured as described above will be described.

  First, the crane 10 is fixed at a work position as shown in FIG. Next, the telescopic boom 16 is extended as necessary and has a predetermined undulation angle. Further, the hook block 19 is lowered and the suspended load is hung on the hook 21. Then, the suspended load is slightly lifted to determine the actual load of the suspended load. This actual load is calculated by a calculation unit (not shown) of the controller 60 based on the cylinder pressure detected by a pressure sensor (not shown) of the hoisting cylinder 18, the hoisting angle of the telescopic boom 16, and the length of the telescopic boom 16. Ask. When the load of the suspended load is known in advance, it may be input by operating a key of an operation unit (not shown).

  On the other hand, as shown in FIG. 3, the surveillance camera 32 is tilted by operating the pan switch SW1 and the tilt switch SW2 so that the hook image 21g always enters the center frame M1 of the screen 70G of the monitor 70.

  When the actual load of the suspended load is obtained by the controller 60 or when a load is input, the work area calculation unit 65 obtains a work area line based on the actual load or the input load.

  On the other hand, the attitude angle calculation unit 63 suspends the hook 21 shown in FIG. 5 from the detection signal output from the boom attitude detection sensor 50, that is, the amount of the wire 25 fed by the winch and the length of the telescopic boom 16. A length L1 is obtained, and an inclination angle θ (an angle in the pan or tilt direction) with respect to the vertical line of the monitoring camera 32 is obtained from the length L1 and the offset W1.

  That is, the posture angle calculation unit 63 tilts the surveillance camera 32 from the tip position information of the telescopic boom 16 (position obtained from the length and the undulation angle of the telescopic boom 16) and the position information of the hook 21 (offset W1 and length L1). Find the angle θ.

  The coordinate position calculation unit 64 obtains the height H1 shown in FIG. 5 based on the detection signal output from the boom posture detection sensor 50, that is, the length and the undulation angle of the telescopic boom 16, and further calculates the height H1. Based on the tilt angle θ of the surveillance camera, the pivot position of the telescopic boom 16 is used as the origin, and the coordinate position of the crane coordinate system corresponding to each position on the captured image is obtained.

  The image composition unit 66 synthesizes (superimposes) the work area line K1 calculated by the work area calculation unit 65 on the image corresponding to the coordinate position of the crane coordinate system calculated by the coordinate position calculation unit 64, as shown in FIG. ) To display on the monitor 70.

  In this first embodiment, the hook image 21g is displaced from the inside of the frame M1 of the screen 70G of the monitor 70 due to ups and downs of the telescopic boom 16 or the vertical movement of the suspended load, etc., but the hook image 21g is the screen of the monitor 70. The operator operates the pan switch SW1 and the tilt switch SW2 so as to always fall within the frame G1 of 70G. Then, the posture angle calculation unit 63 and the coordinate position calculation unit 64 sequentially read the detection signals output from the boom posture detection sensor 50, and the crane coordinates corresponding to the inclination angle θ and each position on the captured image. The coordinate position of the system is obtained, and the work area line K1 is rewritten in real time.

  For this reason, the work area line K1 can be accurately displayed on the screen 70G of the monitor 70 while the hook image 21g is within the frame M1 of the screen 70G of the monitor 70 even when the suspended load is moving. It will be possible.

According to the first embodiment, the posture detection sensor for detecting the posture of the monitoring camera 32 is unnecessary, and the correct work area line K1 is monitored according to the posture angle of the monitoring camera 32 obtained by the posture angle calculation unit 63. The work area line display device 100 can be provided at a low cost.
[Second Embodiment]
FIG. 7 shows the configuration of the work area line display device 200 of the second embodiment. In the second embodiment, a reference setting switch (setting means) SW3 and a memory 201 are provided.
When the pan switch SW1 or the tilt switch SW2 is operated and the hook image 21g enters the frame M1 of the screen 70G of the monitor 70, the switch SW3 is turned on. When this switch SW3 is turned on, the boom posture detection sensor 50 detects it. Based on the detected signal, the attitude angle calculation unit 63 of the controller 260 shown in FIG. 8 obtains the tilt angle (the angle in the pan and tilt directions) of the monitoring camera 32 in the same manner as in the first embodiment.

  When the switch SW3 is turned on, the feed amount of the hook 21, which is a detection signal detected by the boom posture detection sensor 50, and the posture of the telescopic boom 16 (length of the telescopic boom 16, undulation angle, turning angle) Sometimes, the tilt angle (angle in the pan and tilt directions) of the monitoring camera 32 obtained by the posture angle calculation unit 63 is stored in the memory 201 as a reference value.

  Further, when the switch SW3 is turned on, a calculation unit (not shown) of the controller 260 obtains an actual load in the same manner as in the first embodiment, and the actual load and the tilt angle θ of the monitoring camera 32 stored in the memory 201 and the telescopic boom 16 are obtained. The work area calculation unit 65 shown in FIG. 8 obtains a work area line K1 (see FIG. 6) based on the posture of the work area.

  On the other hand, the coordinate position calculation unit 64 obtains the coordinate position of the crane coordinate system at each position on the captured image in the same manner as in the first embodiment. Further, the image composition unit 66 synthesizes the work area line K1 calculated by the work area calculation unit 65 and displays it on the monitor 70 in correspondence with the coordinate position of the crane coordinate system calculated by the coordinate position calculation unit 64 (see FIG. 6).

  That is, in the second embodiment, after the switch SW3 is turned on, the work area line K1 is continuously displayed on the assumption that the hook image 21g is in the frame M1 of the screen 70G of the monitor 70. In the second embodiment, the pan switch SW1 and the tilt switch SW2 are not operated.

  When the hook image 21g deviates from the frame M1 of the screen 70G of the monitor 70 by a predetermined amount or more due to the change in the posture of the telescopic boom 16 and the vertical movement of the hook 21 by the winch, that is, the hook detected by the boom posture detection sensor 50. When the feed amount 21 and the posture data of the telescopic boom 16 (the length of the telescopic boom 16 and the undulation angle) deviate from the reference values stored in the memory 201 by a predetermined value or more, the work area line K1 is displayed on the displayed image. On the other hand, it is determined that there is a large positional deviation error, and an error is displayed. This error display is performed, for example, by displaying characters on the monitor 70, changing the color of the frame M1, or blinking or erasing the work area line K1.

  By displaying this error, the operator can recognize that the displayed work area line is incorrect.

According to the second embodiment, the controller 260 can recognize whether the hook image 21g is located within the frame M1 of the screen 70G, that is, at a predetermined position on the screen 70G.
[Third embodiment]
FIG. 9 shows the configuration of the work area line display device 300 of the third embodiment. Since the controller 360 of the work area line display device 300 has the same configuration as the controller 260 of the second embodiment, the description thereof is omitted.
As in the second embodiment, the work area line display device 300 operates the pan switch SW1 and the tilt switch SW2 so that the hook image 21g enters the frame M1 of the screen 70G of the monitor 70 as shown in FIG. When entering M1, switch SW3 is turned on. When the switch SW3 is turned on, the attitude angle calculation unit 63 (see FIG. 8) of the controller 360 shown in FIG. 9 is based on the detection signal detected by the boom attitude detection sensor 50 in the same manner as in the first embodiment. The inclination angle (angle in the pan and tilt directions) of the monitoring camera 32 is obtained.

  When the switch SW3 is turned on, the feed amount of the hook 21, which is a detection signal detected by the boom posture detection sensor 50, and posture information of the telescopic boom 16 (length of the telescopic boom 16, undulation angle, turning angle), At this time, the tilt angle (angle in the pan and tilt directions) of the monitoring camera 32 obtained by the posture angle calculation unit 63 is stored in the memory 201 as a reference value.

  Further, the work area calculation unit 65 (see FIG. 8) of the controller 360 determines the work area line K1 (see FIG. 6) in the same manner as in the first embodiment based on the inclination angle and height H1 (see FIG. 5) of the monitoring camera 32. The work area line K1 is displayed on the monitor 70 as shown in FIG.

  Thereafter, when the operator operates the pan switch SW1 or the tilt switch SW2, the error of the work area line K1 increases, so that an error is displayed.

  In the third embodiment, after the switch SW3 is turned on, the pan switch SW1 and the tilt switch SW2 are not operated.

  Further, when only the winch is driven after the switch SW3 is turned on, only the hook 21 moves up and down, and the hook image 21g moves out of the frame M1 of the screen 70G of the monitor 70. Unless the SW1 and the tilt switch SW2 are operated, the work area line K1 continues to be displayed at the correct position on the screen 70G of the monitor 70.

  As long as the pan switch SW1 and the tilt switch SW2 are turned on and no error is displayed, the operator can operate the crane under the correct work area line display.

According to the third embodiment, the controller 360 can recognize whether the hook image 21g is located within the frame M1 of the screen, that is, at a predetermined position on the screen 70G.
[Fourth embodiment]
FIG. 10 shows the configuration of the work area line display device 400 of the fourth embodiment. Since the controller 460 of the work area line display device 400 has the same configuration as the controller 260 of the second embodiment, the description thereof is omitted.
As in the second embodiment, the work area line display device 400 operates the pan switch SW1 and the tilt switch SW2 so that the hook image 21g enters the frame M1 of the screen 70G of the monitor 70 as shown in FIG. When entering M1, switch SW3 is turned on. When this switch SW3 is turned on, based on the detection signal detected by the boom posture detection sensor 50, the posture angle calculation unit 63 (refer to FIG. An inclination angle (an angle in the pan and tilt directions) is obtained.

  When the switch SW3 is turned on, the feed amount of the hook 21, which is a detection signal detected by the boom posture detection sensor 50, and the tilt angle (angle in the pan and tilt directions) of the monitoring camera 32 obtained by the posture angle calculation unit 63. ) Is stored in the memory 201 as a reference value.

  Further, the work area calculation unit 65 (see FIG. 8) of the controller 460 determines the work area line K1 (see FIG. 6) in the same manner as the first embodiment based on the inclination angle θ and the height H1 (see FIG. 5) of the monitoring camera 32. ) And the work area line K1 is displayed on the monitor 70 as shown in FIG.

  When the pan switch SW1 or the tilt switch SW2 is operated after the switch SW3 is turned on, it is considered that the hook image 21g of the monitor 70 is put in the frame M1, and the work area line is the same as in the first embodiment. K1 is sequentially obtained, and the work area line K1 displayed on the monitor 70 is rewritten in real time.

  The operator can recognize that the correct work area line is displayed if an operation other than pan / tilt of the camera or a pan / tilt operation in which the hook 21 fits within the frame M1 is performed.

  In any of the above-described embodiments, the inclination angle θ of the monitoring camera 32 is obtained from the length L1 and the offset W1 shown in FIG. 5, but from the position on the image of the hook image 21g and the length L1 by image processing. The tilt angle of the monitoring camera 32 may be obtained. In this case, it is not necessary to put the hook image 21g in the frame M1. Further, there is no need to display the frame M1.

Further, the pan motor 33 and the tilt motor 34 may be controlled by image processing so that the hook image 21g automatically enters the frame M1.
[Fifth embodiment]
FIG. 11 shows a configuration of a work area line display device 500 of the fifth embodiment. The work area line display device 500 includes a monitoring camera 532 that does not have a pan / tilt function. The monitoring camera 532 is provided on the housing 31 (see FIG. 1), and this housing 31 is attached to the tip of the tip boom 16C via a damper (not shown), so that the monitoring camera 532 is caused by its own weight. It is designed to face down.

  When the monitoring camera 532 is facing directly below, the locus E of the hook image 21g when the hook 21 is moved up and down is superimposed on the screen 70G of the monitor 70 as shown in FIG.

  When the monitoring camera 532 is not directed downward due to the action of the damper, the hook image 21g deviates from the locus E, and it can be seen that the displayed work area line K1 is inaccurate.

  When the rotation axis 32J of the surveillance camera 532 and the center D1 of the sheave of the sheave are offset as shown in FIG. 5, the position of the locus E changes depending on the undulation angle of the telescopic boom 16, as shown in FIG. The position of the locus E may be changed to Ea according to the undulation angle. In this case, the work area line K1 is also changed to the correct work area line Ka according to the undulation angle.

  In this embodiment, the description has been made on the assumption that the pan / tilt function is not provided. However, when the surveillance camera 532 is provided with the pan / tilt function, the hook image 21g is positioned on the lines of the trajectories E and Ea. In addition, if the surveillance camera 532 is panned / tilted, the surveillance camera 532 can be directed downward, and the work area lines K1 and Ka displayed on the monitor 70 are also correct work area lines.

  By doing so, the operation of putting the hook image 21g of the monitor 70 in the frame M1 becomes unnecessary, and the calculation process for obtaining the new work area line K1 again becomes unnecessary.

  In any of the above-described embodiments, the frame M1 is displayed at the center of the screen 70G of the monitor 70. However, the frame M1 is not necessarily the center of the screen 70G, and may not be the frame M1. For example, a x mark may be used.

  The present invention is not limited to the above-described embodiments, and design changes and additions are permitted without departing from the spirit of the invention according to each claim of the claims.

DESCRIPTION OF SYMBOLS 10 Crane 16 Telescopic boom 21 Hook 32 Surveillance camera 63 Posture angle calculation part (calculation means)
65 Work area calculation unit 70 Monitor 100 Work area line display device SW1 Pan switch (attitude operation means)
SW2 Tilt switch (Attitude control means)

Claims (7)

A monitor provided at the tip of the boom of the work machine and directed downward, and a monitor that superimposes and displays a work area line indicating a movable area of a suspended load suspended by a hook on an image captured by the camera A work area line display device comprising:
Posture operation means for operating the posture of the camera so that the hook imaged by the camera is positioned at a predetermined position on the screen;
Calculating means for determining the posture angle of the camera based on the position information of the hook and the position information of the boom tip;
A work area line display device characterized in that a correct position of a work area line on the image is obtained according to a camera attitude angle obtained by the computing means, and the work area line is displayed at the obtained position. When the camera is operated and the hook is positioned at a predetermined position on the screen of the monitor, setting means is provided for setting the position of the hook at this time and the attitude angle of the camera as a reference value,
After setting the reference value by this setting means, an error occurs when it is determined that the position of the hook has deviated from the predetermined position on the monitor screen by a predetermined distance or more based on the position of the boom and the operation of the winch for feeding and retracting the hook. The work area line display device according to claim 1. When the camera is operated and the hook is positioned at a predetermined position on the screen of the monitor, setting means is provided for setting the position of the hook at this time and the attitude angle of the camera as a reference value,
The calculation means obtains the correct position of the work area line on the image from the reference value set by the setting means, displays the work area line at the obtained position, and the camera is operated by the posture operation means. The work area line display device according to claim 1, wherein an error occurs.   A frame indicating a predetermined position on the monitor screen is displayed, and the posture of the camera is manipulated so that the hook is positioned within the frame, and the position of the hook and the posture angle of the camera when the hook enters the frame Is set as a reference value, the correct position of the work area line on the image is obtained based on the attitude angle set by the setting means, and the work area line is displayed at the obtained position. The work area line display device according to claim 1.   After the work area line is displayed, when the camera is operated by the posture operation means, the calculation means determines that the operation has been performed so that the hook enters the frame. The attitude angle of the camera is obtained based on the above, the correct position of the work area line on the image is obtained according to the attitude angle of the camera obtained by the computing means, and the work area line is rewritten to the obtained position. The work area line display device according to claim 4, wherein   The work area line display device according to claim 1, wherein the predetermined position is a center position of a monitor screen.   The work area line display device according to any one of claims 1 to 6, wherein the position information of the hook is information on a hook feed amount and a boom posture.