JP2020052630A - Unmanned carrier system - Google Patents

Abstract

To provide an unmanned carrier system in which a distance between a moving shelf and an unmanned carrier is not shifted even when the moving shelf stops at a shifted position.SOLUTION: An unmanned carrier system S comprises: a moving shelf group 1 having a plurality of movable moving shelves 11; an unmanned carrier 3 performing cargo handling to the moving shelves 11; and a management server. The moving shelves 11 each comprise an image storage unit and a projector 114. The moving shelf group 1 further comprises a moving shelf control unit moving the moving shelves 11 to form between the moving shelves 11 a passage P through which the unmanned carrier 3 passes, and projecting a guide image GI on a road surface R of the passage P. The unmanned carrier 3 comprises: an on-vehicle camera 32 imaging the road surface R; a line image detection unit 36 analyzing the imaged image of the road surface R to detect a line image LI in the guide image GI; and a steering control unit 35 controlling a steering on the basis of the line image LI.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an unmanned transport system including a moving shelf and an unmanned transport vehicle.

  2. Description of the Related Art Moving shelves have conventionally been used to improve storage efficiency of warehouses. For example, the moving shelf disclosed in Patent Literature 1 includes a remote input / output device provided on a plurality of moving shelves, an inverter electrically connected to the input / output device, and a traveling motor controlled by the inverter. And control means for managing input / output of the input / output device. The plurality of moving shelves are arranged side by side, and one or more passages are formed between the moving shelves. The control device transmits a command to the inverter via the input / output device to operate the traveling motor in order to form the passage between the moving shelf and the moving shelf. Since the movable shelves are movable, the required occupied area can be reduced as compared with the fixed shelves arranged at predetermined intervals.

  Further, for example, an unmanned transport system using a moving shelf of this type is known, such as an unmanned transport system disclosed in Patent Document 2. The unmanned transport system disclosed in Patent Literature 2 includes a plurality of tire-traveling movable shelves, an unmanned forklift, and a guideway. The moving shelf has a traveling device, and is moved by the traveling device to form a passage between the moving shelves. The guide line is composed of a magnetic tape or the like. The unmanned forklift has a guide sensor for detecting the guide line. The unmanned forklift travels along the guide line while detecting the guide line with the guide sensor, enters a passage formed between the moving shelves, and then unloads the load.

  In this type of a tire-traveling movable shelf, the braking distance is liable to change due to the fact that it is a heavy object loaded with a load and that the surface condition of the road surface is not uniform due to the inclination or unevenness of the road surface. That is, the movable shelf is likely to be deviated from a preset regular stop position and stopped, and the distance from the unmanned forklift often deviates from the regular distance. When such a displacement occurs, there is a problem that the fork of the unmanned forklift cannot be brought close to an appropriate rack position of the movable shelf, and the cargo handling operation of the unmanned guided vehicle cannot be performed properly. Therefore, in the unmanned transport system described in Patent Document 2, a preliminary position detector is provided on the road surface, and the movable shelf has a sensor for detecting the preliminary position detector. The movable shelf detects the preliminary position detecting body by this sensor, temporarily stops at the preliminary position retracted from the regular stop position, and moves to the regular position after the automatic guided vehicle enters the passage, The deviation of the distance from the unmanned forklift is eliminated.

  However, providing the preliminary position detecting body on the road surface in advance is troublesome and requires a large installation cost. Further, in the case of an unmanned transport system in which a preliminary position detector is provided on the road surface, it is necessary to provide the preliminary position detector every time the layout is changed indoors.

JP-A-6-293410 JP-A-2003-81410

  Therefore, the problem to be solved by the present invention is that even if a displacement occurs when the movable shelf stops from the moving operation without laying the detecting object or the like on the road surface, the moving shelf and the automatic guided vehicle are separated. An object of the present invention is to provide an unmanned transport system in which the distance does not shift.

In order to solve the above problems, an unmanned transfer system according to the present invention
A moving shelf group having a plurality of moving shelves having a moving mechanism, arranged in parallel, and moved in a parallel direction by the moving mechanism,
An unmanned transport system that travels along the guidance line and performs an unloading operation with respect to the moving shelf.
An image storage unit in which a line image as the guide line is stored,
A projection unit that is provided for each of the moving shelves and projects the line image;
Controlling the moving mechanism, moving the plurality of moving shelves to each other to form a passage through which the automatic guided vehicle passes between the moving shelves, and controlling the projection unit, and forming the passage on the road surface of the formed passage A moving shelf control unit for projecting a line image,
The automatic guided vehicle,
A first imaging unit for imaging the road surface;
A line image detection unit that detects the line image as the guide line by analyzing an image of the road surface captured by the first imaging unit;
A steering control unit that performs steering control based on the detected guidance line.

The unmanned transport system is preferably
Further comprising a management server capable of communicating with the moving shelf control unit and the automatic guided vehicle,
The management server stores cargo handling information including information on the cargo handling work to be performed by the automatic guided vehicle,
The image storage unit stores a plurality of the line images,
The management server transmits cargo handling information to the moving shelf control unit and the automatic guided vehicle by the communication,
The cargo handling information includes color information of the line image to be projected by the projection unit,
The moving shelf control unit extracts the line image of the color corresponding to the color information from the image storage unit, and projects the extracted line image on the road surface of the passage on which the extracted line image is formed,
The line image detection unit detects the line image corresponding to the color information as the guide line on which the automatic guided vehicle should travel.

The unmanned transport system is preferably
A second imaging unit provided for each of the moving shelves, while capturing the line image projected on the road surface,
An image correction unit that corrects the line image based on the image captured by the second imaging unit.

The image correction unit is preferably
Based on each luminance of each color component of each pixel of the line image captured by the second imaging unit and each luminance of each color component of each pixel of the line image stored in the image storage unit, A correction coefficient calculation unit that calculates a correction coefficient of each color component of each pixel of the line image,
A correction processing unit that corrects each luminance of each color component of each pixel of the line image using the correction coefficient.

  In the automatic guided vehicle system according to the present invention, the distance between the movable shelf and the automatic guided vehicle is shifted even when the movable shelf stops moving from the moving operation without laying the detection object or the like on the road surface. Can be prevented.

(A) is a top view showing an outline of the automatic transfer system according to the present invention, and (b) is a side view thereof. FIG. 2 is a functional block diagram of the unmanned transfer system in FIG. 1. (A) is a perspective view of the moving shelf of FIG. 1, (b) is a figure which shows the front of the moving shelf of FIG. 1, and the side surface of the automatic guided vehicle of FIG. (A) is a figure which shows an example of the guidance image projected on the road surface, (b) is a figure which shows the guidance image before correction, (c) is a top view which shows the guidance image after correction | amendment It is. (A) is a top view showing the automatic guided vehicle of FIG. 1 and a guidance image, and (b) is a top view showing the automatic guided vehicle of FIG. 1, a guidance image, and an existing line.

  Hereinafter, an embodiment of an unmanned transport system according to the present invention will be described with reference to the accompanying drawings. The directions X, Y, and Z in the front-rear, left-right, and up-down directions are based on the traveling direction of the automatic guided vehicle shown in FIG.

  FIG. 1 is a schematic diagram of an unmanned transport system S using a movable shelf 11 according to the present invention. The unmanned transport system S includes a moving shelf group 1 including a plurality of moving shelves 11, a management server 2 (see FIG. 2), and an unmanned transport vehicle 3. When unloading work is assigned to the unmanned transport vehicle 3 from the management server 2, the unmanned transport system S moves the movable shelf 11 to allow the unmanned transport vehicle 3 to enter an area in front of the movable shelf 11 related to the unloading operation. A path P is formed, and an image for guiding the automatic guided vehicle 3 is projected on a road surface R of the path P.

<Management server>
As shown in FIG. 2, the management server 2 can communicate with the automatic guided vehicle 3 by wireless communication means, and can communicate with the moving shelf control unit 15 by wireless or wire. The management server 2 stores cargo handling information (hereinafter, simply referred to as cargo handling information) including information on cargo handling work to be performed by the automatic guided vehicle. The management server 2 transmits the cargo handling information to the automatic guided vehicle 3 and the moving shelf control unit 15 by communication.

<Moving shelf>
As shown in FIGS. 1 and 3, the moving shelf group 1 includes a plurality of moving shelves 11 for storing cargo, and has a cargo handling information storage unit 14 and a moving shelf control unit 15.

  The moving shelves 11 are arranged side by side, and include a frame 111, a plurality of mounting spaces 112 surrounded by the frame 111, a moving mechanism 113, a projector 114, and an image storage unit 115.

  The placing space 112 is a space for placing luggage related to cargo handling work.

  The moving mechanism 113 has a plurality of wheels (four in this embodiment) 113a provided on the bottom of the moving shelf 11, and motors (not shown) connected to the respective wheels 113a. The movable shelf 11 moves in the parallel direction (see the arrow W in FIG. 1A and FIG. 3A) when the motor 113 operates and the wheels 113a rotate.

  The image storage unit 115 is provided for each moving shelf 11. The image storage unit 115 stores a guidance image GI including a line image LI for guiding the automatic guided vehicle 3.

  The projector 114 is provided above the movable shelf 11 so as to face the road surface R. The projector 114 projects the guidance image GI stored in the image storage unit 115 on the road surface R. The projector 114 corresponds to the “projection unit” of the present invention.

  As shown in FIG. 4A, in the guide image GI, a line image LI having a certain width is arranged at the center, and the direction in which the line image LI extends is the direction in which the automatic guided vehicle 3 is guided. Further, the color of the line image LI is clearly different in hue, lightness, and saturation as compared with the two sides SI. This guidance image GI is merely an example and is not limited to this. Further, the image storage unit 115 stores a plurality of guidance images GI in which the color of the line image LI and the color of the two sides SI thereof are different.

  The cargo handling information storage unit 14 stores the cargo handling information transmitted from the management server 2 to the moving shelf control unit 15. The cargo handling information also includes information on the automatic guided vehicle 3 to which the command has been issued, position information of the mobile shelf 11 to be subjected to cargo handling, and color information of the guidance image GI to be projected (that is, color information of the line image LI). ). Hereinafter, the color information of the guidance image GI to be projected is simply referred to as “color information”.

  The moving shelf control unit 15 operates the motor of the moving mechanism 113 to move the moving shelf 11 in accordance with the cargo handling information stored in the cargo handling information storage unit 14, and moves the path P ( 1 (see FIG. 1). The width of the passage P may be changed for each piece of cargo handling information based on the width of the vehicle body 31 of the automatic guided vehicle 3 included in the cargo handling information, or may be limited to a predetermined width.

  Next, the moving shelf control unit 15 extracts a guidance image GI corresponding to the received color information from the guidance image GI stored in the image storage unit 115. Next, the moving shelf control unit 15 controls the projector 114 to project the extracted guidance image GI on the road surface R of the path (hereinafter, simply referred to as “path”) P formed. The position where the guidance image GI is projected may be changed for each piece of cargo handling information based on the width of the vehicle body 31 of the automatic guided vehicle 3 included in the cargo handling information.

<Automated guided vehicle>
As shown in FIGS. 1, 2, and 5, the automatic guided vehicle 3 includes a vehicle body 31, a vehicle-mounted camera 32, a pair of left and right front wheels 33, a pair of left and right rear wheels 34, and a front wheel 33 and a rear wheel 34. The vehicle includes a steering control unit 35 that performs steering control of one or both of them, a line image detection unit 36, a fork 37, a mast 38, and a storage unit 39. The automatic guided vehicle 3 is an unmanned forklift provided with a three-way stacking mechanism, but is merely an example and is not limited to this.

  The storage unit 39 stores the cargo handling information received by the automatic guided vehicle 3.

  The in-vehicle camera 32 is tilted in the road surface direction and rotatably connected to a center position of the upper surface of the vehicle body 31 so that the vehicle surface 32 can be imaged on the road surface R in the traveling direction when the vehicle is moving forward and backward. The in-vehicle camera 32 corresponds to the “first imaging unit” of the present invention. The position of the vehicle-mounted camera 32 is merely an example, and is not limited to this.

  As shown in FIG. 5A, the vehicle-mounted camera 32 captures a predetermined imaging range T of the road surface R to generate a road surface image, and outputs the road surface image to the line image detection unit 36.

  The line image detection unit 36 analyzes the input road surface image based on the hue, saturation, and lightness, and outputs the line image LI corresponding to the color information stored in the cargo handling information storage unit 14 to the automatic guided vehicle 3. It is detected as a guide line to run. That is, the line image detection unit 36 detects the line image LI related to the cargo handling work to which the automatic guided vehicle 3 is assigned as the guidance line, and the line image LI not related to the cargo handling work is included in the road surface image. Is not detected as a guide line. The line image LI is more easily detected by the line image detecting unit 36 due to the presence of both side portions SI.

  Thereby, even if the in-vehicle camera 32 captures the line image LI projected from the projector 114 of the movable shelf 11 that is not related to its own cargo handling operation, the automatic guided vehicle 3 travels along the line image LI. There is no. Therefore, even if a plurality of AGVs 3 receive a cargo handling command from the management server 2 at the same time, the AGVs 3 do not go to the mobile shelves 11 unrelated to their own cargo handling, It can go only to the moving shelf 11 related to the work.

  In addition, the line image detecting unit 36 includes an image of a line (hereinafter, referred to as “existing line”) EL provided in advance on the road surface R shown in FIG. When the image LI is not included, the existing line EL is detected as a guide line to travel. In other words, the line image detecting unit 36 preferentially detects the line image LI over the existing line EL as a guide line, but can also detect the existing line EL as a guide line. The existing line EL may be, for example, a tape type line or a line provided by painting.

  The steering control unit 35 controls the steering of one or both of the front wheel 33 and the rear wheel 34 based on the guide line detected by the line image detection unit 36 (that is, the line image LI or the existing line EL). . Specifically, the steering control unit 35 feedback-controls the steering angles of the wheels 33 and 34 so that the position of the guidance line is located at the center of the imaging range T. Thereby, the automatic guided vehicle 3 can be guided along the guidance line and head toward the movable shelf 11.

  Next, the flow of the unmanned transport system S will be described. First, the management server 2 transmits the cargo handling information to the automatic guided vehicle 3 as a cargo handling command by wireless communication. The management server 2 also transmits the cargo handling information transmitted to the automatic guided vehicle 3 to the moving shelf control unit 15. The cargo handling information storage unit 14 and the storage unit 39 each store the received cargo handling information.

  The automatic guided vehicle 3 travels along the existing line EL based on the cargo handling information stored in the storage unit 39 and heads to the entrance of the passage P.

  The moving shelf control unit 15 forms a path P between the moving shelf 11 related to the received cargo handling information and the moving shelf 11 facing the moving shelf 11. Next, the moving shelf control unit 15 extracts the guidance image GI corresponding to the color information stored in the cargo handling information storage unit 14 from the image storage unit 115, and projects the extracted guidance image GI by the projector 114. As shown in FIGS. 1A and 5B, the guidance image GI is projected to reach the existing line EL.

  When the automatic guided vehicle 3 arrives at the entrance of the passage P, the line image detection unit 36 detects the line image LI in the guidance image GI from the road surface image captured by the on-vehicle camera 32. The steering control unit 35 performs steering control based on the line image LI detected by the line image detection unit 36.

  The automatic guided vehicle 3 enters the path P by traveling along the line image LI, and performs the cargo handling operation based on the cargo handling information stored in the storage unit 39.

  As described above, the automatic guided vehicle 3 enters the passage P along the line image LI in the guidance image GI projected by the projector 114 installed on the moving shelf 11, so that when the passage P is formed, Even if the movable shelf 11 stops at a position shifted from the predetermined position, the separation distance between the movable shelf 11 and the automatic guided vehicle 3 does not shift. Therefore, the automatic guided vehicle 3 can appropriately perform the cargo handling work without laying the detection body or the like on the road surface R.

  By the way, as shown in FIG. 4B, the road surface R may be stained or peeled off depending on the use condition. In this case, a part of the guidance image GI such as the portion A is not appropriately displayed. . Therefore, the moving shelf control unit 15 controls the image correction unit 17 to analyze the guidance image GI projected on the road surface R and correct the guidance image GI so as to correspond to such a road surface R. Hereinafter, a specific description will be given.

  As shown in FIGS. 1 and 3, the moving shelf 11 further has a shelf camera 116. Further, as shown in FIG. 2, the moving shelf group 1 further has an image correction unit 17.

  The shelf camera 116 captures the guidance image GI projected on the road surface R of the passage P, and generates a road surface image. The shelf camera 116 corresponds to the “second imaging unit” of the present invention. The shelf camera 116 is fixed to an upper portion of the movable shelf 11 so as to face the road surface R.

  The image correction unit 17 includes a correction coefficient calculation unit 171 and a correction processing unit 172. The guidance image GI stored in the image storage unit 115 is output to the correction coefficient calculation unit 171 and the projector 114 via the correction processing unit 172. The projector 114 projects the input guidance image GI on the road surface R. The shelf camera 116 captures the projected guidance image GI, generates a road surface image, and outputs the road surface image to the correction coefficient calculation unit 171.

  The correction coefficient calculation unit 171 normalizes each luminance of each pixel of the guide image GI for each color component to generate input data D1, and also calculates each luminance of each pixel of the road surface image output from the shelf camera 116 with each color component. The output data D2 is generated by normalizing the data. Next, the correction coefficient calculation unit 171 checks the input data D1 and the output data D2, and calculates a correction coefficient of each color component of each pixel for adjusting the luminance ratio between each pixel of the output data D2 to the input data D1. Then, the calculated correction coefficient is output to the correction processing unit 172.

  The correction processing unit 172 corrects the luminance of each color component of each pixel of the guided image GI1 to be projected using the calculated correction coefficient of each color component of each pixel, and generates a guided image GI2. Next, the correction processing unit 172 outputs the generated guidance image GI2 to the projector 114 and also outputs to the correction coefficient calculation unit 171. The projector 114 projects the input guidance image GI2 on the road surface R. The shelf camera 116 captures the projected guidance image GI2, generates a road surface image, and outputs the road surface image to the correction coefficient calculation unit 171. The correction coefficient calculation unit 171 calculates a correction coefficient corresponding to the guidance image GI2 as described above.

  As shown in FIG. 3C, by repeating this process, the finally projected guidance image GI is displayed like an image projected on a monochrome screen. As described above, since the guide image GI projected by the projector 114 is corrected at any time by the correction processing unit 172, the guide image GI can be appropriately displayed even if the road surface R as the projection surface is partially stained. For this reason, the automatic guided vehicle 3 can appropriately detect the line image LI in the guidance image GI regardless of the state of the road surface R, and can appropriately travel along the line image LI. The positioning can be appropriately performed on the movable shelf 11.

  The embodiment of the unmanned transport system S according to the present invention has been described above, but the present invention is not limited to the above embodiment.

  (1) The projector 114 may be composed of a plurality of projectors. In this case, a wide range of guidance images GI may be displayed on the road surface R by simultaneously projecting a plurality of guidance images GI by a plurality of projectors.

  (2) For example, only one image storage unit 115 may be provided in the entire moving shelf group 1.

  (3) For example, only the guidance image GI including the one-color line image LI may be stored in the image storage unit 115. In this case, the moving shelf control unit 15 causes the image correction unit 17 to change the color of the line image LI to a color corresponding to the color information in the received cargo handling information, and the changed guidance image GI is projected by the projector 114 onto the road surface R. May be projected.

  (4) The moving mechanism 113 may be composed of, for example, a rail laid on the road surface R and wheels provided on the bottom of the moving shelf 11.

  (5) The existing line EL may be a line projected by a projector provided on a ceiling or the like.

1 Moving shelf group 11 Moving shelf 112 Mounting space 113 Moving mechanism 113a Wheel 114 Projector (projection unit)
115 Image storage unit 116 Shelf camera (second imaging unit)
3 Automated guided vehicle 31 Body 32 On-board camera (first imaging unit)
33 Front wheel 34 Rear wheel 35 Steering control unit 36 Line image detecting unit S Unmanned transport system GI Guide image LI Line image SI Both side portions R of guide image R Road surface T Imaging range

The unmanned transport system is preferably
Further comprising a management server capable of communicating with the moving shelf control unit and the automatic guided vehicle,
The management server stores cargo handling information including information on the cargo handling work to be performed by the automatic guided vehicle,
The image storage unit stores a plurality of the line images,
The management server transmits cargo handling information to the moving shelf control unit and the automatic guided vehicle by the communication,
The cargo handling information includes color information of the line image to be projected by the projection unit,
The moving shelf control unit extracts the line image of the color corresponding to the color information from the image storage unit, and projects the extracted line image on the road surface of the passage on which the extracted line image is formed,
The line image detection unit detects the line image corresponding to the color information as the guide line on which the automatic guided vehicle should travel.

As shown in FIG. 4 (c), by which the process is repeated, eventually projected induced image GI is displayed as an image projected to a single color screen. As described above, since the guide image GI projected by the projector 114 is corrected at any time by the correction processing unit 172, the guide image GI can be appropriately displayed even if the road surface R as the projection surface is partially stained. For this reason, the automatic guided vehicle 3 can appropriately detect the line image LI in the guidance image GI regardless of the state of the road surface R, and can appropriately travel along the line image LI. The positioning can be appropriately performed on the movable shelf 11.

Claims (4)

A moving shelf group having a plurality of moving shelves having a moving mechanism, arranged in parallel, and moved in a parallel direction by the moving mechanism,
An unmanned transport system that travels along the guidance line and performs an unloading operation with respect to the moving shelf.
An image storage unit in which a line image as the guide line is stored,
A projection unit that is provided for each of the moving shelves and projects the line image;
The moving mechanism is controlled to move the plurality of moving shelves with each other to form a passage through which the automatic guided vehicle passes between the moving shelves, and to control the projection unit, and to form the passage on the road surface of the formed passage. A moving shelf control unit for projecting a line image,
The automatic guided vehicle,
A first imaging unit for imaging the road surface;
A line image detection unit that detects the line image as the guide line by analyzing an image of the road surface captured by the first imaging unit;
An unmanned transport system, comprising: a steering control unit that performs steering control based on the detected guidance line. Further comprising a management server capable of communicating with the moving shelf control unit and the automatic guided vehicle,
The management server stores cargo handling information including information on the cargo handling work to be performed by the automatic guided vehicle,
The image storage unit stores a plurality of the line images,
The management server transmits the cargo handling information to the moving shelf control unit and the automatic guided vehicle by the communication,
The cargo handling information includes color information of the line image to be projected by the projection unit,
The moving shelf control unit extracts the line image of the color corresponding to the color information from the image storage unit, and projects the extracted line image on the road surface of the passage on which the extracted line image is formed,
The unmanned transport system according to claim 1, wherein the line image detecting unit detects the line image corresponding to the color information as the guide line on which the unmanned transport vehicle travels. A second imaging unit provided for each of the moving shelves, while capturing the line image projected on the road surface,
The unmanned transport system according to claim 1, further comprising: an image correction unit configured to correct the line image based on an image captured by the second imaging unit. The image correction unit,
Based on each luminance of each color component of each pixel of the line image captured by the second imaging unit and each luminance of each color component of each pixel of the line image stored in the image storage unit, A correction coefficient calculation unit that calculates a correction coefficient of each color component of each pixel of the line image,
The unmanned transport system according to claim 3, further comprising: a correction processing unit configured to correct each luminance of each color component of each pixel of the line image using the correction coefficient.

Images