JP2628008B2 - Visual recognition of operating state of work machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for remotely controlling a work machine at a construction site from a remote control point remote from the construction site, and more particularly to a system for moving a work machine over a wide range or at a remote control point. The present invention relates to a remote control system for a work machine that is suitable when there is an object that interferes with communication between the work machine and the work machine.

[0002]

2. Description of the Related Art In recent years, working machines such as crawler dumps, bulldozers, and power shovels have been provided on site, and the working machines have been remotely operated from remote locations such as site offices and city offices remote from the site. Have been tried. In remote control of the work machine, a television camera is installed on the cab or roof of the work machine, and the television camera shoots a scene of the site in front of the work machine viewed from the work machine, and the captured image is taken. The data is transmitted wirelessly to a remote operation location, displayed on a monitor television set at the remote operation location, and an operator at the remote operation location controls the work machine while watching the displayed image.

When the operator remotely operates the work machine, the operator checks the operation state of the work machine and whether there are obstacles such as rocks that hinder the operation of the work machine in the vicinity. Therefore, it is necessary to visually confirm the state of the work machine and the surrounding site in addition to the state of the work site in front of the work machine. In addition, for example, when the work machine is operated autonomously according to a predetermined operation pattern while the position of the work machine is constantly checked by automatic surveying, the autonomous operation of the work machine cannot be performed due to an unexpected situation. In this case, it is necessary to switch the work machine from the autonomous operation to the manual operation by remote control. At this time, it is necessary to visually confirm the state of the work machine and the surrounding site similarly to the above.

In order to remotely control the work machine, conventionally, a camera platform is installed at one corner of a site and a television camera is installed on the camera platform to remotely control the direction of the camera platform from the remote operation location. The work machine and the surrounding site are photographed while appropriately changing the conditions, and the photographed image is transmitted wirelessly to a remote operation location and displayed on the monitor television in the same manner as described above.

[0005]

However, in the above-mentioned conventional system, the work machine moves around the work site, whereas the work machine and the surroundings of the work site are photographed by a television camera. Since the position is fixed to a corner of the site, if the work machine is hidden behind trees or other work machines as the work machine moves, it becomes impossible to take an image of the work machine or its surroundings with the television camera, There has been a problem in that it is not possible to check the operating state of the work machine or the presence or absence of an obstacle that hinders the operation at the remote operation location. The present invention has been made in view of the above circumstances, the object of the present invention,
Provided is a method for visually confirming the operating state of a remotely operated work machine that enables the operating state of a moving work machine and the presence or absence of an obstacle that hinders operation to be reliably grasped at a remotely operated place of the work machine away from the site. Is to do.

[0006]

According to the present invention, there is provided a method for visually recognizing an operation state of a work machine movably disposed on a site at a remote place remote from the site. A moving body is arranged at the site, the moving body is moved in the site following the work machine, and the work machine is photographed by the photographing means from the moving body, and an image photographed by the photographing means Transmitting wirelessly from the mobile unit to the remote location by transmitting means, and disposing a display means at the remote location, and displaying the image transmitted by the transmitting means on the display means. Features.

Further, in the present invention, the photographing means is disposed on the moving body via a head that can be displaced in a directional direction.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing a schematic configuration of a remote control system of a power shovel to which the method of the present invention is applied. In FIG. 1, 1 is a work site, 3 is an excavation site (corresponding to a site), 5
Is a relay point, and 7 is a remote control point (corresponding to a remote location).

The excavation site 3 is located at one corner of the work site 1, where excavation of the ground 33 using a power shovel 31 (corresponding to a work machine) is performed by remote control from the remote control point 7 side. An operation of the power shovel 31 is photographed by a camera robot 35 (corresponding to a moving body) that moves on the excavation site 3 following the power shovel 31 and transmitted to the remote control point 7. The excavator 31
Is a crawler 310 as shown in FIGS.
1, swivel 3103, boom 3105, bucket 310
7 and a cockpit 3109.

In the cockpit 3109, as shown in FIG. 2 (b), a pair of left and right stereoscopic television cameras 3111 for photographing the work area of the bucket 3107, and sound in the work area is collected stereoscopically. A binaural microphone 3113 is provided. Above the cockpit 3109, as shown in FIG. 2B, an image captured by the stereoscopic television camera 3111 and a sound collected by the binaural microphone 3113 are provided. A transmitter 3115 for transmitting a signal using UHF band radio waves is provided. As shown in FIG. 2C, the swivel 3103 is provided with a radio control box 3117 for controlling the operation of the power shovel 31 by remote control from the remote control point 7 side. As shown in FIG. 2 (c), the receiver 31 of the specific weak power type
19 are provided.

Power shovel 31 and camera robot 3
As shown in FIG. 3 which is a block diagram showing a schematic configuration of the control system of the fifth embodiment, the power shovel 31 includes an engine 3121 which is a drive source of a crawler 3101 and a drive source of a swivel 3103, a boom 3105 and a bucket 3107. And a certain hydraulic pressure source 3123. Also, the crawler 3101
A drive control circuit 3125 is interposed between the hydraulic circuit 3125 and the hydraulic power source 3123 between the turntable 3103, the boom 3105, and the bucket 3107.
27, and the radio control box 31
17 are connected. In addition, radio control box 31
17 is connected to a receiver 3119, as shown in FIG.
The drive control circuit 3125 and the hydraulic circuit 3127 are controlled so that each part of the power shovel 31 is driven based on the remote control radio control signal received at 19.

As shown in FIG. 1, the camera robot 35 includes a crawler 3501 and a chassis 3503. Above the chassis 35, a receiver 3505 and a transmitter 3507 (corresponding to transmission means) of a specific weak power type are provided. Arranged, and
The surveillance camera 3511 and the microphone 3513
Reference numeral 9 denotes a support which is supported so as to be displaceable in the directional direction in the three-dimensional direction.

As shown in FIG. 3, the camera robot 35
An engine 3515 that is a driving source of the crawler 3501;
A drive control circuit 3517 and a radio control box 3519 are provided.
505, a pan head 3509, a monitoring camera 3511 (corresponding to a photographing unit), and a drive control circuit 3517. Each part of the camera robot 35 is driven based on a remote control radio control signal received by the receiver 3505. The head 3509 and the drive control circuit 3517 are controlled so as to be controlled. The transmitter 3507 is connected to the monitoring camera 3511.
And the signal of the sound collected by the microphone 3513 is transmitted to the relay point 5 side.

[0014] As shown in FIG.
Is set at a relatively small place in the work site 1 where there is no obstacle between the work site 1 and the excavation site 3 and there is no obstacle between the excavation site 3 and the relay van 51 is movably disposed. ing. As shown in FIG. 1, in addition to the steered wheels, drive wheels, an engine, a drive control device (not shown), the relay vehicle 51 has a connection between the power shovel 31 or the camera robot 35 and the remote operation point 7. A relay unit 5101 for relaying a signal transmitted by the wireless communication device is mounted.

As shown in FIG. 4, the relay unit 5101 includes specific weak power type receivers 5103 and 5105, transmitters 5107 and 5109, a stereoscopic image generation device 5111,
Screen quadrant 5113, millimeter wave communication unit 511
5, relay box 5117, and link terminal 5
119. Receivers 5103 and 5105 and transmitters 5107 and 5109 are provided on roof 512 of broadcast van 51.
It is installed on 1

The receiver 5103 receives an image taken by the stereoscopic television camera 3111 and a binaural microphone 311 transmitted from the transmitter 3115 of the power shovel 31.
Similarly, the receiver 5105 receives an image captured by the monitoring camera 3511 or a microphone 3513 transmitted from the transmitter 3507 of the camera robot 35. This is to receive the radio wave of the collected voice signal. Transmitters 5107 and 51
Reference numeral 09 denotes a radio control signal for controlling the drive of the power shovel 31 and the camera robot 35 transmitted from the remote control point 7 to the receiver 3119 of the power shovel 31 and the receiver 3505 of the camera robot 35. is there.

The stereoscopic image generation device 5111 includes a receiver 5
A pair of left and right stereoscopic television cameras 3 received at 103
The two captured images 111 are alternately captured and synthesized to generate a stereoscopic image. The screen four-segmentation device 5113 divides the screen for stereoscopic vision generated by the stereoscopic vision image generation device 5111 and the captured image of the surveillance camera 3511 received by the receiver 5105 into four screens. In addition to performing image synthesis and selection processing to simultaneously display images in the divided areas or to display only one of the images on one screen, the synthesis and selection of the image signal are performed. The audio signal components collected by the binaural microphone 3113 and the microphone 3513 are separated.

The millimeter-wave communication unit 5115 communicates with the remote operation point 7 via a millimeter-wave line through an antenna 5123 installed on a roof 5121 of the relay vehicle 51 as shown in FIG. Then, as shown in FIG.
There are two video signal systems VIDEO and two stereo sound signal systems SOUND1 and SOUND2. The input terminal IN of the video signal system VIDEO receives the signal of the image synthesized and selected by the screen quadrant 5113, and as shown in FIG. 4, the output terminal OUT1 (1) of the first stereo audio signal system SOUND1. (L, R) is connected to a link terminal 5119.

The second stereo audio signal system S
The audio signal separated by the screen quadrant 5113 is input to the input terminal IN2 (L, R) of OUND2, and the transmitters 5107, 5109 are output to the output terminal OUT2 (L, R) as shown in FIG. Is connected. The input terminal IN1 of the first stereo sound signal system SOUND1
Nothing is connected to (L, R) or the video signal output system VIDEO-OUT.

The relay box 5117 is provided with a screen quadrant 5113, a changeover switch 5125, and an output terminal OUT1 of the first stereo sound signal system SOUND1.
(L, R) are selectively connected, and the switching state is switched by the control of the link terminal 5119. The relay box 5117 and the link terminal 5119 transmit the radio control signal from the remote operation point 7 to the receiver 3 of the power shovel 31.
119 or the receiver 3505 of the camera robot 35, or the screen quadrant 5113
The remote operation control signal from the remote operation point 7 for performing the operation of switching the selected image
It is provided for selective transmission to the switch 113 and the changeover switch 5125.

As shown in FIG. 1, the remote control point 7 is away from both the excavation site 3 and the junction point 5 and cannot directly see the excavation site 3, for example, a site office 71 ( (Corresponding to a monitoring center), and a remote operation unit 73 operated by a remote operation person 75 is installed. As shown in FIG. 5, the remote control unit 73 includes a millimeter wave communication unit 7301 and a stereoscopic monitor 73.
03 (corresponding to display means), host computer 730
5, relay board 7307, link terminal 730
9, a radio control box 7311, 7313, and a speaker 7315.

The millimeter wave communication unit 7301 is provided with an antenna 7317 installed on the roof 7101 of the site office 71.
Through a millimeter-wave line with the relay point 5, as shown in FIG. 5, one video signal system VIDEO and two stereo audio signal systems SOUN.
D1 and SOUND2. Note that the video signal system VIDEO and the stereo audio signal systems SOUND1 and SOUND2 of the millimeter wave communication unit 7301 are the video signal system VIDEO of the millimeter wave communication unit 5115 at the relay point 5.
O, stereo sound signal system SOUND1, SOUND2
Respectively.

From the output terminal OUT of the video signal system VIDEO of the millimeter wave communication unit 7301, the image is synthesized by the screen quadrant 5113 of the relay unit 5101 at the relay point 5, and
The selected image signal is input to the video signal system VIDEO of the millimeter wave communication unit 5115, and is output. 5 is connected to the output terminal OUT of the video signal system VIDEO.
, A stereoscopic monitor 7303 is connected.

The stereoscopic monitor 7303 includes a relay vehicle 5
The image selected by the screen quadrant 5113 of the relay unit 5101 is displayed, and the displayed image is input to the host computer 7305 and selected by the screen quadrant 5113 of the relay unit 5101 of the relay truck 51. Switching in response to a signal instructing. For example, when an instruction to select a stereoscopic image generated by the stereoscopic image generation device 5111 is given, the screen quadrant 511 is displayed.
3 selects and outputs only the stereoscopic image, and the stereoscopic image is displayed on the stereoscopic monitor 7303.

On the other hand, the monitoring camera 3 of the camera robot 35
If a selection is made to display only the images captured in 511 or to display the stereoscopic image and the monitoring image simultaneously, the screen quadrant 5113 selects and outputs those images. These images are displayed by applying the display screen of the stereoscopic monitor 7303 to each of four sections. In cases other than the case where the stereoscopic image is displayed alone, the connection between the output terminal OUT of the video signal system VIDEO of the millimeter wave communication unit 7301 and the host computer 7305 is slightly changed to change the connection of the host computer 7305. You may make it display on CRT7323 mentioned later.

Also, the input terminal I of the first stereo audio signal system SOUND1 of the millimeter wave communication unit 7301
A link terminal 7309 is connected to N1 (L, R). As shown in FIG.
A relay board 7307 is provided between the link terminal 305 and the link terminal 7309. These relay boards 7
The remote control input 307 and the link terminal 7309 are input to the host computer 7305 by remote control input relating to switching of the changeover switch 5125 mounted on the relay vehicle 51 at the relay point 5 and remote control input relating to switching of the selected image of the screen quadrant 5113. Sometimes, the connection state of the relay box 5117 of the relay unit 5101 is switched in conjunction with this.

When an input relating to the above-mentioned remote operation is provided to the host computer 7305, a switching control signal having a content corresponding to the input is transmitted from the relay board 7307 to the link terminal 7309 and the millimeter wave communication unit 7301.
Is transmitted to the millimeter-wave communication unit 5115 of the relay point 5 via the link, and the switching control signal is input to the link terminal 5119 of the relay point 5, and the connection state of the relay box 5117 is controlled by the control of the link terminal 5119 accordingly. Switch.

On the other hand, as shown in FIG. 5, the second stereo audio signal system SOU of the millimeter wave communication unit 7301
The two radio control boxes 731 are connected to the input terminal IN2 (L, R) of the ND2 via a changeover switch 7319 whose connection state is switched by an operation of a keyboard 7325 or the like of the host computer 7305 described later.
1,7313 are connected.

The radio control box 7311 is for remotely driving the crawler 3101, the swivel base 3103, the boom 3105, and the bucket 3107 of the power shovel 31. And an operation lever (not shown) which is tilted for a time corresponding to the time. The radio control signal for drive control of the power shovel 31 generated by the operation of the operation lever or the like is transmitted via the changeover switch 7319 to the millimeter wave communication unit 7301 and the millimeter wave communication unit 511 of the relay point 5.
5, the signal is input to the radio control box 3117 via the transmitter 5107 and the receiver 3119 of the power shovel 31.

The radio control box 7313 is for driving the crawler 3501, the camera platform 3509, and the surveillance camera 3511 of the camera robot 35 by remote control. The radio control box 7313 moves in a direction corresponding to these operation directions. An operation lever (not shown) that is tilted in a corresponding direction for a time corresponding to the amount of movement is provided. A radio control signal for drive control of the power shovel 31 generated by operating the operation lever or the like is supplied to a changeover switch 7319.
Is input to the radio control box 3519 via the millimeter wave communication unit 7301, the millimeter wave communication unit 5115 at the relay point 5, the transmitter 5109, and the receiver 3505 of the camera robot 35.

Further, from the output terminal OUT2 (L, R) of the second stereo audio signal system SOUND2, the screen quadrant 511 of the relay unit 5101 of the relay point 5 is output.
The audio signal separated at 3 is output. The output terminal OUT2 of the second stereo audio signal system SOUND2
A speaker 7315 is connected to (L, R) as shown in FIG.
The binaural microphone 3113 provided in the camera robot 35 and the microphone 3513 provided in the camera robot 35 collect sound.
The sound is selectively output from the speaker 7315, and the collected sound of the binaural microphone 3113 is reproduced so as to be three-dimensionally audible. In addition, the input terminal IN (L, R) of the video signal system VIDEO of the millimeter wave communication unit 7301
Nothing is connected to the output terminal OUT1 (L, R) of the first stereo sound signal system SOUND1.

As shown in FIG. 5, the host computer 7305 includes a computer main body 7321, a CRT 7323,
A keyboard 7325 and a mouse 7327 are provided. The keyboard 7325 and the mouse 7327 are connected to the
Selection of the connection target of the changeover switch 5125 of No. 1 and the screen 4
This is for selecting an image in the dividing device 5113 and the like.

When the remote control of the power shovel 31 is performed using the power shovel remote control system of the present embodiment having the above-described configuration, the remote control personnel 75 operates the keyboard 7325 or the like to divide the screen of the broadcast truck 51 into four screens. Device 5
In response to a selection screen switching instruction input to 113, an image of the work area of bucket 3107 captured by stereoscopic camera 3111 of power shovel 31 is displayed on the screen of stereoscopic monitor 7303.

Also, in response to a switching instruction input of the changeover switch 7319 by operating the keyboard 7325 or the like, a radio control box 7311 is connected to the input terminal IN2 (L, R) of the second stereo sound signal system SOUND2 of the millimeter wave communication unit 7301. The switch 5125 is switched to the transmitter 5107 side in response to an instruction to switch the connection target of the switch 5125 of the relay truck 51 by operating the keyboard 7325 or the like. Then, the remote control personnel 75 is connected to the stereoscopic monitor 7.
The operator operates the operation lever and the like of the radio control box 7311 while viewing the screen of 303.

When the operation lever or the like of the radio control box 7311 is operated, a signal for drive control of the power shovel 31 according to the operation content is transmitted to the changeover switch 7319, the millimeter wave communication units 7301 and 5171, and the transmitter 510.
7. Via the receiver 3119, the remote operation point 7 to the relay point 5
RC box 31 of excavator 31 via
17 is sent. Radio control box 31 receiving this
17 controls the drive control circuit 3125 and the hydraulic circuit 3127 of the power shovel 31 in accordance with the operation contents of the operation lever and the like of the radio control box 7311 by the remote control personnel 75 at the remote control point 7, and controls the crawler 3101 and the swivel base 3
103, the boom 3105, and the bucket 3107 are driven.

In the case where there is an obstacle such as a rock in the work area of the excavator 31 during the remote operation of the excavator 31, the excavator 31 is remotely operated while avoiding the obstacle. For example, moving the camera robot 35 to the vicinity of the excavator 31 to cause the surveillance camera 3511 to photograph the excavator 31 from a desired direction, and remotely controlling the excavator 31 while viewing the image. Become.

Therefore, in such a case, the remote operation personnel 75 operates the relay truck 5 by operating the keyboard 7325 or the like.
In response to the input of an instruction to switch the selection screen to the screen division unit 5113, the image of the work area of the bucket 3107 photographed by the stereoscopic camera 3111 of the power shovel 31 and the surveillance camera 35 are displayed on the screen of the stereoscopic monitor 7303.
The image captured in step 11 is combined and displayed on one screen. At this time, only the image captured by the monitoring camera 3511 may be displayed on the screen of the stereoscopic monitor 7303.

Also, in response to a switching instruction input of the changeover switch 7319 by operating the keyboard 7325 or the like, a radio control box 7313 is input to the input terminal IN2 (L, R) of the second stereo sound signal system SOUND2 of the millimeter wave communication unit 7301. The switch 5125 is switched to the transmitter 5109 in response to an input of an instruction to switch a connection target of the switch 5125 of the relay truck 51 by operating the keyboard 7325 or the like. Then, the remote control personnel 75 is connected to the stereoscopic monitor 7.
The operator operates the operation lever and the like of the radio control box 7311 while viewing the screen of 303.

When an operation lever or the like of the radio control box 7311 is operated, a signal for drive control of the power shovel 31 according to the operation content is transmitted to the changeover switch 7319, the millimeter wave communication units 7301 and 5171, and the transmitter 510.
9. From the remote control point 7 to the relay point 5 via the receiver 3505
Radio control box 35 of camera robot 35 via
19 is sent. Radio control box 35 receiving this
19 controls the drive control circuit 3517 of the camera robot 35 according to the operation contents of the operation lever and the like of the radio control box 7311 by the remote operation person 75 at the remote operation point 7 to drive the crawler 3501 and Is moved to a desired location around the excavator 31.

The radio control box 3519 controls the pan head 3509 and a zoom drive control unit (not shown) of the surveillance camera 3511 in accordance with the operation contents of the operation lever and the like, and drives the pan head 3509 to monitor the surveillance camera. The pointing direction of 3511 is displaced toward the power shovel 31, and
The monitoring camera 3511 is zoomed so that the power shovel 31 is photographed in a desired size. When the position of the power shovel 31 is largely changed by the movement, the camera robot 35 is appropriately moved as described above so as to always follow the power shovel 31.

As described above, according to this embodiment, the camera robot 35 is movably disposed near the power shovel 31 at the excavation site 3, and the remote control personnel 75 on the remote control point 7 side.
The excavator 31 is operated by remote control by the operation of the radio control box 7313 by the operator, and the camera robot 35 follows the excavator 31 by the operation of the radio control box 7311 by the remote operation personnel 75.
Is moved, and the surveillance camera 3511 of the camera robot 35 is zoomed or the direction of the pan head 3509 supporting the surveillance camera 3511 is displaced. 7 is displayed on the stereoscopic monitor 7303.

Therefore, when the excavator 31 moves in the excavation site 3 in various directions, the camera robot 35 is moved to follow the excavator 31 so that, for example, the excavator 31 is viewed from the vehicle 51 at the relay point 5 or the like. Hiding behind trees or other work machines, or excavators 3
Even if the distance to 1 becomes long to some extent, the operation status of the power shovel 31 can be reliably grasped at the remote control point 7 side,
The presence or absence of an obstacle that hinders the operation of the power shovel 31 can be constantly checked at the remote operation point 7 side.

In this embodiment, the case where the remote operation point 7 communicates with the power shovel 31 and the camera robot 35 via the relay point 5 has been described. Direct communication may be performed, and communication between the remote operation point 7 and the power shovel 31 may be performed via the camera robot 35. Alternatively, between the relay point 5 and the power shovel 31 or the camera robot 35, one or more additional relay points formed of a movable vehicle or the like are further provided, and via the relay point and the relay point 5, The remote operation point 7 may communicate with the power shovel 31 or the camera robot 35, and one of the one or a plurality of relay points may be shared with the camera robot 35.

Further, the communication means among the remote operation point 7, the relay point 5, the power shovel 31, and the camera robot 35 is a transmission / reception means of a millimeter wave communication or a specific weak power type as shown in this embodiment. It is not limited to. However, the communication between the remote control point 7 and the work site 1 side is desirably performed using relatively long-distance communication such as millimeter-wave communication. Depending on the setting, one suitable for long-distance communication or one suitable for short-distance communication may be appropriately selected and used.

In this embodiment, the power shovel 31
Has been described by remote control from the remote control point 7, the method of the present invention determines the operation pattern of the power shovel 31 in advance and automatically operates the power shovel 31 according to the pattern,
For example, the power shovel 31 is automatically surveyed from the relay point 5 or the like at any time, and the result is compared with the operation pattern of the power shovel 31 while the power shovel 31 is checked.
Can also be applied to the case where is operated autonomously. In such a case, the excavator 31 and the camera robot 3
5 may be provided with a two-way automatic tracking means so that the camera robot 35 automatically follows the movement of the power shovel 31. Further, it goes without saying that the present invention can be applied to a case where the operation status of various working machines such as a crawler dump and a bulldozer is visually recognized at a remote place, other than the power shovel 31 shown in the embodiment.

[0046]

As described above, according to the present invention, there is provided a method of visually recognizing the operating condition of a work machine movably disposed at a site at a remote location remote from the site, wherein the method comprises the steps of: Disposing a body, moving the moving body in the site following the work machine, photographing the work machine with photographing means from the moving body, and displaying an image photographed by the photographing means with the moving body. Since the transmitting means wirelessly transmits to the remote location by the transmitting means, and the display means is disposed at the remote location, and the video transmitted by the transmitting means is displayed on the display means. It is possible to reliably ascertain the operation status of the work machine and the presence or absence of an obstacle that hinders the operation at a remote operation site of the work machine away from the site.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a remote control system of a power shovel to which a method of the present invention is applied.

2 (a) is a plan view, FIG. 2 (b) is a front view, and shows a configuration of a power shovel at an excavation site shown in FIG.
FIG. 2C is a side view.

FIG. 3 is a block diagram showing a schematic configuration of a control system of the power shovel and the camera robot shown in FIG. 1;

FIG. 4 is a block diagram showing a schematic configuration of a relay unit mounted on a vehicle at a relay point shown in FIG. 1;

FIG. 5 is a block diagram showing a schematic configuration of a remote control unit provided in a site office at a remote control point shown in FIG. 1;

[Explanation of symbols]

 3 Excavation site (site) 31 Power shovel (work machine) 35 Camera robot (mobile) 3507 Transmitter (transmitting means) 3509 Pan head 3511 Surveillance camera (photographing means) 7 Remote operation point (remote point) 7303 Stereoscopic monitor ( Display means)

Claims (2)

(57) [Claims] 1. A method for visually recognizing an operation state of a work machine movably disposed on a site at a remote location remote from the site, wherein a mobile is disposed on the site, and the mobile is Following the work machine, the work machine is moved in the field, the work machine is photographed by the photographing means from the moving body, and the image photographed by the photographing means is wirelessly transmitted from the mobile body to the remote location by the transmission means. And a display means is provided at the remote location, and the image transmitted by the transmitting means is displayed on the display means. 2. The method according to claim 1, wherein the photographing means is disposed on the moving body via a head that can be displaced in a directional direction.