JP2009236784A - Apparatus, method and mark for detecting position - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus, method and mark for easily and accurately detecting a position. <P>SOLUTION: The apparatus for detecting a position includes a camera and a control unit. The camera moves to take an image of a position detecting mark. The position detecting mark has different-color areas and a plurality of boundary lines formed by contacting of the areas, and the boundary lines cross each other on a line passing through a predetermined reference position. The control unit detects lightness on a plurality of scanning lines in a pick-up image of the position detecting mark, obtains intersecting points of the scanning lines and the boundary lines based on change of the lightness, obtains the plurality of boundary lines based on a plurality of intersecting points, obtains boundary line crossing positions where the plurality of boundary lines cross each other, determines a line connecting a plurality of boundary line crossing positions as the above line, and specifies the reference position based on the line. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a position detection device, a position detection method, and a position detection mark for grasping the current position of a moving body.

  It is important to accurately grasp the current position of the transfer device in order to safely run the transfer device installed in a warehouse or factory. As a method of grasping the current position of the transport device, marks indicating the reference position when moving in the moving direction of the transport device are set at predetermined intervals, and the transport device travels while identifying this mark, thereby There is a method of running while grasping the position.

Patent Documents 1 and 2 disclose an invention in which a mark indicating a predetermined reference position is captured by an imaging device, and the captured image is processed to grasp the positional relationship between the mark and the imaging device. Yes. In Patent Document 1, a detection body is installed on the center of a mark indicating a predetermined reference position and on a concentric circle thereof, so that even if the detection body has a defect, the mark can be detected stably. An invention that can be made is disclosed. Further, Patent Document 2 discloses an invention in which pattern matching processing can be performed without performing processing such as scale processing even when the size of a mark in a captured image changes due to a change in imaging distance.
JP 2001-291095 A JP 2003-28614 A

However, the invention disclosed in Patent Document 1 has a large error because it detects a plurality of detectors arranged concentrically and obtains the center position from them.
Further, the invention disclosed in Patent Document 2 takes time for processing because it uses pattern matching.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a position detection device, a position detection method, and a position detection mark that can detect a position easily and accurately.

  In order to achieve the above object, a position detection device according to a first aspect of the present invention includes a region having a different color and a plurality of boundary lines formed in contact with the region, on a line passing through a predetermined reference position. In the camera that moves and images the position detection mark including the reference position detection mark formed so that the boundary line intersects with each other, and a plurality of scans in the captured image of the position detection mark captured by the camera A color detection means for detecting a color on the line; and an intersection for obtaining an intersection position between the scanning line and the boundary line in the reference position detection mark based on a change in color on the scanning line detected by the color detection means Position deriving means, boundary line deriving means for obtaining a plurality of the boundary lines from a plurality of intersection positions obtained by the intersection position deriving means, and a boundary intersection where the plurality of boundary lines obtained by the boundary line deriving means intersect Position Crossing position deriving means, and a reference position specifying means for determining a line connecting a plurality of boundary line crossing positions obtained by the crossing position deriving means as the line, and specifying the reference position based on the line; It is characterized by providing.

  For example, the position detection mark is further arranged with a predetermined distance from the reference position, and further includes a position reading code in which position information of the reference position is encoded, specified by the reference position specifying means Reading position setting means for setting the reading position of the position reading code using the reference position, and position information reading means for reading the position information displayed on the position reading code at the position set by the reading position setting means And may be further provided.

  For example, a deviation calculating unit that calculates a deviation between a reference point in the image captured by the camera and the reference position, the deviation calculated by the deviation calculating unit, and the position information read by the position information reading unit And a camera position detecting means for detecting the position of the camera based on the above.

  A position detection method according to a second aspect of the present invention is a position detection method for a moving object including a camera, and includes a region having a different color and a plurality of boundary lines formed in contact with the region, In an imaging step of causing the camera to image a position detection mark formed so that the boundary line intersects on a line passing through a reference position, and a captured image of the position detection mark captured in the imaging step, a plurality of A color detection step for detecting a color on the scanning line; an intersection position derivation step for obtaining an intersection position between the scanning line and the boundary line based on a change in the color on the scanning line detected in the color detection step; A boundary line deriving step for obtaining a plurality of the boundary lines from a plurality of intersection positions obtained in the intersection position deriving step, and a boundary line intersection where the plurality of boundary lines obtained in the boundary line deriving step intersect An intersection position deriving step for obtaining a position, and a reference position identifying step for determining a line connecting the plurality of boundary line intersection positions obtained in the intersection position deriving step as the line and identifying the reference position based on the line And.

  A position detection mark according to a third aspect of the present invention includes a reference position detection mark for detecting a predetermined reference position, and a position reading code in which position information of the reference position is encoded, The reference position detection mark includes a plurality of regions having different colors, and a plurality of boundary lines formed by contacting the different regions intersect on a line passing through the reference position.

  For example, the position information may be a distance from a predetermined position to the reference position.

  For example, the position reading code may be a barcode.

  For example, a position display unit expressing the position information with characters may be further provided.

  According to the present invention, the position can be detected easily and accurately.

  Hereinafter, a load transporting facility including a position detection device according to an embodiment of the present invention will be described with reference to the drawings. The baggage transport facility moves the camera together with a crane used to transport the baggage, images and analyzes the position detection marks installed at each location, and detects the position of the baggage transport facility itself.

  As shown in FIGS. 1 and 2, the luggage transport facility 100 includes a position detection mark 10, a guide rail 20, a moving body 30, a camera controller 40, a camera 45, a motor controller 50, and a moving motor 55. The crane controller 60, the crane 65, and the control part 70 are provided.

  As shown in FIG. 1, the two guide rails 20 are arranged in parallel, and support the movable body 30 so that it can be guided in the direction indicated by the arrow in the figure. Moreover, the guide rail 20 is comprised from the steel material provided with sufficient rigidity which can support the mobile body 30. FIG.

  The moving body 30 is fixedly attached with a camera 45 and a crane 65, and moves along the guide rail 20 using a moving motor 55. More specifically, a plurality of wheels (not shown) driven by the moving motor 55 are attached to the lower surface of the moving body 30. A plurality of wheels are provided at positions of the guide rails 20 that are spaced apart from each other, and the moving body 30 is supported by the guide rails 20 via the plurality of wheels.

  Upon receiving an instruction from the control unit 70, the camera controller 40 causes the camera 45 to execute a required operation and transfers an image captured by the camera 45 to the control unit 70.

  The camera 45 images the position detection mark 10 in accordance with an instruction from the camera controller 40. More specifically, the camera 45 is a monochrome camera, and the viewing angle and imaging distance of the camera 45 are taken into consideration so that at least one position detection mark 10 can be always imaged among a plurality of position detection marks 10 described later. Has been.

  The motor controller 50 receives an instruction from the control unit 70 and causes the moving motor 55 to execute a required operation.

  The moving motor 55 is attached to the lower surface of the moving body 30 and moves the moving body 30 in accordance with instructions from the motor controller 50.

  The crane controller 60 receives an instruction from the control unit 70 and causes the crane 65 to perform a required operation.

  The crane 65 is attached to the lower surface of the moving body 30 and performs loading and unloading according to instructions from the crane controller 60.

The control unit 70 includes, for example, a ROM (Read Only Memory), a CPU (Central Processing Unit), a RAM (Random Access Memory), and the like, and includes color detection means, intersection position derivation means, and boundary line derivation. It functions as a means, an intersection position deriving means, a reference position specifying means, a reading position setting means, a position information reading means, a deviation calculating means, and a camera position detecting means. The ROM stores an operation program, the CPU controls the entire luggage transport facility 100 according to the operation program, and the RAM functions as a work area for the CPU.
The control unit 70 is connected to the camera controller 40, the motor controller 50, and the crane controller 60, and controls them.
Specifically, the control unit 70 captures the position detection mark 10 with the camera 45 while moving the moving body 30, and grasps the current position of the moving body 30 by processing the captured image. And if the mobile body 30 moves to a target position, it will stop.

A mark installation surface 80 provided vertically is formed along the two guide rails 20, and the control unit 70 determines the position of the crane (moving body 30) on the mark installation surface 80. The position detection mark 10 is arranged.
As shown in FIG. 1, a plurality of position detection marks 10 are installed on the mark installation surface 80 with a predetermined interval (0.2 m in this embodiment).

  As shown in FIG. 3, the position detection mark 10 includes a position display unit 11 that displays a distance from a predetermined reference position (the origin of a plurality of installed position detection marks 10) to the position detection mark 10; It comprises a reference position detection mark 12 for detecting the installation reference position of the position detection mark 10 and a position reading code 13 in which the display contents on the position display section 11 are encoded.

  The position display unit 11 is expressed by arithmetic numbers and is set to a size that can be recognized from a viewpoint field assumed by an operator or the like who operates and monitors the moving body 30.

The reference position detection mark 12 indicates the installation reference position 19 of the position detection mark 10, and the moving body reference line 14 that penetrates the reference position detection mark 12 in the vertical direction in the drawing is in the moving direction of the moving body 30. The installation reference position 19 of the position detection mark 10 is represented. A height reference line 15 orthogonal to the moving body reference line 14 represents the installation reference position of the position detection mark 10 in the vertical direction in the figure. Note that the moving body reference line 14 and the height reference line 15 are lines drawn in the drawing for convenience in describing the reference position detection mark 12. On the right side of the moving object reference line 14 in the figure, a black right-angled isosceles triangle 16 is formed with the moving object reference line 14 as a base and a point on the height reference line 15 as a vertex. Further, on the left side of the moving body reference line 14 in the figure, a white painted isosceles triangle 17 and a black with corners formed on the height reference line 15 so as to cover the hypotenuse of the right isosceles triangle 17. A painted L-shaped portion 18 is formed.
A boundary line 12 a and a boundary line 12 b are formed at the boundary between the right isosceles triangle 17 and the L-shaped portion 18. A boundary line 12 c is formed at the boundary between the right-angled isosceles triangle 17 and the right-angled isosceles triangle 16. A boundary line 12d and a boundary line 12e are formed at the boundary between the right isosceles triangle 16 and the outside of the mark.
The point where the boundary lines 12a and 12b intersect and the point where the boundary lines 12d and 12e intersect are formed on the height reference line 15. In addition, the boundary line 12 c is formed on the moving body reference line 14. The point where the boundary lines 12a and 12d intersect and the point where the boundary lines 12b and 12e intersect are formed on the moving body reference line 14.

  The position reading code 13 is obtained by encoding the display contents of the position display unit 11 in binary, and is composed of I to V units shown in the figure. The I part is a 1-bit part representing the start of reading the position reading code 13, the II part is a 10-bit part representing the integer part (integer 363) of the position display part 11, and the III part is a decimal part (decimal point) of the position display part 11. The 4-bit part representing the first 4), the IV part is a 1-bit part of the added parity code for detecting erroneous reading, and the V part is a 1-bit part representing the end of reading of the position reading code 13. . The full width L of the position reading code 13 is determined based on the shutter speed of the camera 45 and the moving speed of the moving body 30, and is set to a width that allows the position reading code 13 to be read from the captured image.

  The mark installation surface 80 is set to a color having a brightness difference, in this case, white so that the black portion of the position detection mark 10 can be easily detected. When the mark installation surface 80 is installed outdoors, a bracket (not shown) to which a flat plate is attached is extended from the guide rail 20 so that one surface of the flat plate can be used as the mark installation surface 80.

  Next, a method for detecting the position detection mark 10 and aligning the moving body 30 will be described with reference to the flowcharts shown in FIGS.

Hereinafter, the positioning process of the moving body performed by the luggage transport facility 100 will be described with reference to the flowchart shown in FIG.
When receiving an instruction to move the moving body 30 to a predetermined destination from the outside or from an operation program stored in the ROM, the control unit 70 automatically performs the following operation according to the program stored in the ROM. .

  First, the control unit 70 controls the motor controller 50 to operate the motor 55 and move the moving body 30 in a predetermined direction (S100).

  The control unit 70 controls the camera controller 40 to cause the camera 45 to image the position detection mark 10 (S200).

  The control unit 70 acquires the image captured in S200, sets an appropriate threshold value, and performs binarization processing of the captured image (S300). For the binarization processing of the captured image, a known processing method can be arbitrarily selected.

  The control unit 70 sets a plurality of scanning lines crossing the reference position detection mark 12 using the binarized captured image, and the control unit 70 functioning as a color detection unit changes the color on the scanning line. It detects and specifies the installation reference position of the position detection mark 10 (intersection of the moving body reference line 14 and the height reference line 15 shown in FIG. 3) (S400). The procedure of S400 (reference position detection process) will be described later in detail. Since the reference position detection mark 12 of this embodiment is composed of white and black, brightness is detected as color detection of this embodiment. For this reason, the subsequent color detection by the color detection means is described as lightness detection.

  Next, the control unit 70 functioning as a color detection unit detects the lightness on the scanning line that crosses the position reading code 13 using the binarized captured image. Then, the control unit 70 reads the position reading code 13 and obtains a distance (position information D) from a predetermined reference position. From this position information D and the installation reference position of the position detection mark 10 obtained in S400, the current position of the moving body 30 is obtained (S500). The procedure of S500 (distance code acquisition process) will be described later in detail.

  Subsequently, the control unit 70 determines whether the current position of the moving body 30 obtained in S500 is a target position (S600).

  If it is determined in S600 that the moving body 30 is at the target position (S600; YES), the control unit 70 stops the moving body 30 (S700) and ends the process.

  If it is determined in S600 that the moving body 30 is not at the target position (S600; NO), the controller 70 causes the camera 45 to re-image the position detection mark 10 after t seconds (S800), and returns the process to S300. Then, the binarization process (S300) of the captured image is performed again, and the positioning of the moving body 30 is performed according to the flowchart below. The time t is automatically calculated from the moving speed of the moving body 30 and the amount of deviation of the current position of the moving body from the target position.

  Next, the reference position detection process in S400 will be described in detail with reference to FIG. 5, FIG. 6, and FIG. Here, S410 to S450 shown in FIG. 5 are intersections between the scanning lines S0 to S4 crossing the reference position detection mark 12 and the black and white boundary of the reference position detection mark 12, as shown in FIG. 8A. This is a step of detecting detection points P0 to P8 indicating The respective heights of the scanning lines S0 to S4 in the captured image are based on the size of the reference position detection mark 12 and the imaging distance, and a plurality of detection points can be obtained with respect to a predetermined boundary as will be described later. Is set to

  First, the control unit 70 functioning as a color detection unit detects the brightness of the pixels on the scanning line S0. Then, the control unit 70 functioning as the intersection position deriving unit obtains the positions of the detection points P2 and P3 indicating the intersection between the scanning line S0 and the black and white boundary line (S410). More specifically, the control unit 70 performs processing by a Sobel filter or the like on the scanning line S0, and the point that the brightness changes from dark to bright at the beginning detected by the control unit 70 functioning as color detection means. The control unit 70 functions as the intersection position deriving unit to set the detection point P2, and the second time point that changes from dark to light is set to the detection point P3.

  Next, the control unit 70 functioning as a color detection unit detects the brightness of the pixels on the scanning line S1, and the control unit 70 functions as an intersection position deriving unit to obtain the positions of the detection points P1 and P4 ( S420). More specifically, the control unit 70 performs a process using a Sobel filter or the like on the scanning line S1, and changes the brightness from dark to bright at the beginning detected by the control unit 70 functioning as a color detection unit. The control unit 70 functions as the intersection position deriving unit to set the detection point P1, and the second time point that changes from dark to bright is set to the detection point P4.

  Subsequently, the control unit 70 functioning as the color detection unit detects the brightness of the pixel on the scanning line S2, and the control unit 70 functions as the intersection position deriving unit to obtain the position of the detection point P0 (S430). . More specifically, the control unit 70 performs processing by a Sobel filter or the like on the scanning line S2, and the brightness changes from light to dark at the second time detected by the control unit 70 functioning as color detection means. Is set as a detection point P0 by the control unit 70 functioning as an intersection position deriving unit.

  The control unit 70 functioning as the color detection unit detects the brightness of the pixel on the scanning line S3, and the control unit 70 functions as the intersection position deriving unit to obtain the positions of the detection points P5 and P8 (S440). More specifically, the control unit 70 performs processing by a Sobel filter or the like on the scanning line S3, and changes the brightness from dark to bright at the beginning detected by the control unit 70 functioning as a color detection unit. The control unit 70 functions as an intersection position deriving unit and sets it as a detection point P5, and a point that changes from dark to bright for the second time is set as a detection point P8.

  Subsequently, the control unit 70 functioning as the color detection unit detects the brightness of the pixel on the scanning line S4, and the control unit 70 functions as the intersection position deriving unit to obtain the positions of the detection points P6 and P7 ( S450). More specifically, on the scanning line S4, the control unit 70 performs processing by a Sobel filter or the like, and the point that the brightness changes from dark to bright at the beginning detected by the control unit 70 functioning as a color detection unit is as follows. The control unit 70 functions as an intersection position deriving unit and sets it as a detection point P6, and a point that changes from dark to bright for the second time is set as a detection point P7.

  The control unit 70 specifies the installation reference position of the position detection mark 10 in the captured image based on the positions of the detection points P0 to P8 obtained in S410 to S450, and also specifies the installation reference position of the specified position detection mark 10. And the deviation in the height direction in the figure from the designed installation reference position is calculated (S460). The procedure of S460 (reference position and deviation amount calculation process) will be described later in detail.

  Next, the reference position and shift amount calculation processing in S460 will be described with reference to FIGS. 6 and 8A.

  First, the control unit 70 determines whether the position of the detection point P0 indicating the intersection of the scanning line S2 and the black-and-white boundary line of the reference position detection mark 12 is obtained (S461).

  If it is determined that the position of the detection point P0 is not obtained (S461; NO), the control unit 70 uses a straight line formula that passes through the detection point P1 and the detection point P2 obtained in S410 and 420 on the plane of the captured image. The control unit 70 functions as a boundary line deriving unit (S462).

  Similarly, the control unit 70 functioning as the boundary line deriving unit obtains an equation of a straight line passing through the detection points P3 and P4 obtained in S410 and 420 (S463).

  Next, the control unit 70 functions as an intersection position deriving unit, and obtains an intersection between the straight line P1-P2 (a straight line passing through the detection point P1 and the detection point P2; the same shall apply hereinafter) and the straight line P3-P4. The unit 70 functions as a reference position specifying unit, and the obtained intersection position is set as an installation reference position P0-x of the position detection mark 10 in the moving direction of the moving body 30 in the captured image (S464).

  Subsequently, the control unit 70 functioning as a boundary line deriving unit obtains an equation of a straight line passing through the detection points P5 and P6 obtained in S440 and 450 (S465).

  Next, the control unit 70 functions as an intersection position deriving unit to obtain an intersection between the straight line P1-P2 and the straight line P5-P6, and detects the intersection position in the captured image in the height direction in the figure. It is set as P0-y of the installation reference position of the mark 10 for use (S466).

  Subsequently, the control unit 70 calculates a deviation amount ΔP0-y in the height direction in the drawing between the installation reference position P0-y of the position detection mark 10 and the scanning line S2 (S467). Here, the scanning line S2 is set to coincide with the height reference line 15 shown in FIG. 3 by design. However, a deviation occurs between the scanning line S2 and the height reference line 15 (FIG. 3) due to construction errors of the position detection marks 10 and the guide rails 20 and the like. ΔP0-y represents this deviation amount.

  If it is determined that the position of the detection point P0 has been obtained (S461; YES), the control unit 70 sets the coordinates of the detection point P0 in the moving direction of the moving body 30 as the installation reference position P0-x of the position detection mark 10. (S468).

  Next, the control unit 70 functions as a boundary line deriving unit, obtains an equation of a straight line passing through the detection point P1 and the detection point P2 as in S462 (S469), and shifts the processing to S465.

  Subsequently, the control unit 70 functioning as a deviation calculating unit calculates the deviation amount ΔP0-y by the procedure from S465 to S467 as described above.

  Next, the distance code acquisition process in S500 will be described with reference to FIGS. 7 and 8B.

  The scanning line S5 shown in FIG. 8B is set to a height that crosses the center of the position reading code 13 in advance. However, as described above, when a deviation amount ΔP0-y occurs between the scanning line S2 and the height reference line 15 (FIG. 3), the scanning line S5 deviates from the center of the position reading code 13 by a distance of ΔP0-y. It will be.

  Therefore, first, the control unit 70 functioning as the reading position setting means adds a deviation amount ΔP0-y to the preset height of the scanning line S5, and performs a new scan across the center of the position reading code 13. The line S5 ′ is set (S510).

Next, the control unit 70 functions as a color detection unit, detects the brightness of the pixel on the scanning line S5 ′ set in S510, and the control unit 70 functions as a position information reading unit to detect the position of the position detection mark 10. Information D is acquired (S520).
Subsequently, the control unit 70 determines the center (arbitrary position) of the imaging screen in the moving direction of the moving body 30 (x coordinate in FIG. 8, where the moving direction of the moving body 30 is a negative direction). ) Is equal to or greater than the installation reference position P0-x of the position detection mark 10, that is, whether the imaging center of the camera 45 does not exceed the installation reference position P0-x (S530).

  When the imaging center of the camera 45 does not exceed the installation reference position P0-x (S530; YES), the control unit 70 functions as a camera position detection unit, and P0-x is determined from the value of the position information D. The value calculated by subtracting the value divided by the value A is set as the current position (S540), and the process ends. The predetermined value A is for converting a dimension (distance) handled on the screen (analytical) into an actual dimension.

  When the imaging center of the camera 45 exceeds the installation reference position (S530; NO), the control unit 70 functions as camera position detection means, and P0-x is set to a predetermined value A from the value of the position information D. The value calculated by adding the divided values is used as the coordinates of the current position (S550), and the process is terminated.

  In this way, the luggage transport facility 100 can calculate an accurate current position in which the relative shift between the photographing center of the camera 45 and the installation reference position is added to the position information D.

  As described above, when the position detection device using the position detection mark according to the embodiment of the present invention is used, the image of the position reading code 13 is scanned, or the position display unit 11 is directly visually recognized by an operator or the like. As a result, the position of the moving body 30 within the moving range can be directly grasped. As a result, it is possible to reduce erroneous recognition of the position of the moving body 30 due to malfunction of the driving device or erroneous detection of the position detection mark. In particular, it is important where the position detection mark that gives the reference position is located in the moving range for a conveying device with a large moving range, such as a crane device installed in a warehouse or factory. The technique according to the present invention is particularly effective.

  In addition, since the black-and-white boundary line of the reference position detection mark 12 intersects on a line orthogonal to the installation reference position of the position detection mark 10, the installation of the two-dimensional position detection mark 10 is performed by scanning from one direction. The reference position can be specified. As a result, the position detection mark 10 can be detected more easily than in the prior art.

The present invention is not limited to the above embodiment, and various modifications and applications are possible.
In the above-described embodiment, the case where the five scanning lines S0 to S4 are set and the intersection points P0 to P8 are detected when the installation reference position of the position detection mark 10 is specified has been described. Can freely set its position and number.

  For example, as a method for specifying the installation reference position of the position detection mark 10 by reducing the number of intersections to be detected, the following method may be mentioned. Scan lines S1 and S3 shown in FIG. 8 are set, and intersection points P1, P4, P5, and P8 are detected. Since the shape of the reference position detection mark 12 is known, the inclination of each boundary line passing through the detected intersections P1, P4, P5, and P8 can be known. Thereby, the expression of each boundary line can be obtained, and the setting reference position of the position detection mark 10 can be determined in the same manner as described above.

  Further, the total number of detected intersections may be increased by increasing the number of intersections detected in each scanning line or increasing the set number of scanning lines. As a result, even if there is an intersection that has not been detected for some reason, it is possible to easily specify the installation reference position of the position detection mark using the normally detected intersection.

  For example, even if the intersection point P0 on the scanning line S2 is not detected, it can be obtained from the intersection point of the straight line P1-P2 and the straight line P3-P4 as in the above-described embodiment, or by a scanning line other than the scanning line S2. If the position of the intersection with the moving body reference line (FIG. 3) is detected, this position can be used as a substitute for the intersection P0. Furthermore, if P2 and P3 are detected, the midpoint can be substituted for P0.

  In this way, a method for specifying the installation reference position of the position detection mark 10 from the obtained intersections can be freely selected. Further, when some of the intersections are not detected, other installation reference positions can be selected. By changing to the identification method, the installation reference position can be easily identified.

  Further, the position display unit 11 is not necessarily installed on all the position detection marks 10, and may be installed with a predetermined interval (for example, 1 m).

  Further, the reference position detection mark 12 is not limited to the mark described in the above embodiment. FIG. 9 shows another example of the reference position detection mark.

  The reference position detection mark 71 shown in FIG. 9A is arranged with a pair of vertices opposed to black squares facing in the vertical direction in the figure, and the reference position detection mark is set as the reference position detection mark. The barycentric position of 71 is set. Four scanning lines 72 crossing the reference position detection mark 71 are set, and eight intersections 73 between the scanning lines 72 and the black and white boundaries are detected. In this example, the installation reference position in the moving direction of the moving body cannot be obtained directly, but by obtaining a linear expression of each side of the square from the intersection 73, the installation reference position of the position detection mark can be specified.

  The reference position detection mark 74 shown in FIG. 9B is arranged with a pair of vertices opposed to a black square frame in the vertical direction in the drawing, and the installation reference position of the position detection mark is The center of gravity of the reference position detection mark 74 is set. Four scanning lines 75 crossing the reference position detection mark 74 are set, and 16 intersections 76 between the scanning lines 75 and the black and white boundary lines are detected. Also in this example, the installation reference position in the moving direction of the moving body cannot be obtained directly, but double intersections can be detected as compared with the example of FIG. Therefore, even when some of the intersections 76 are not detected, it is possible to obtain the installation reference position of the position detection mark using the other detected intersections 76.

  The reference position detection mark 77 shown in FIG. 9C is arranged with the right-angled portion of the black isosceles right triangle, and the installation reference position of the position detection mark is set at the butting portion of the right-angled triangle. ing. Four scanning lines 78 crossing the reference position detection mark 77 are set, and 16 intersections 79 between the scanning lines 78 and the black and white boundary lines are detected. In this example, by obtaining a linear expression of a black and white boundary line crossed at a butt portion of a right triangle and obtaining an intersection point thereof, it is possible to specify the installation reference position of the position detection mark.

  Colors are expressed as quantitative values of hue, saturation, luminance, and brightness, but it is not always necessary to detect all of the colors detected by the control unit functioning as color detection means. For example, in the above-described embodiment, the reference position detection mark including a region having a different color and a plurality of boundary lines formed in contact with the region by separately painting with a color having no hue (monotone) is provided. Formed. The present invention is not limited to this, and the region and the boundary line may be defined by a color having a hue. In this case, for example, a color camera may be used as a camera, and a change in the region and a boundary line (upper point) may be determined based on a change in chromaticity and luminance of each pixel. In addition, a monochrome camera may be used to determine the region only by luminance while ignoring the hue.

It is a perspective view of the load transportation equipment concerning an embodiment of the present invention. It is a lineblock diagram of the load transportation equipment concerning an embodiment of the present invention. FIG. 5 is a detailed view showing a position detection mark according to the embodiment of the present invention. The flowchart which showed the process of the positioning of the moving body using the position detection mark which concerns on embodiment of this invention. The flowchart which showed the detection process of the installation reference position of the mark for position detection. The flowchart which showed the process which calculates | requires the installation reference position of the position detection mark, and the deviation | shift amount of a position detection mark and a moving body. The flowchart which showed the reading process of a position reading code. The top view which showed the scanning position (a)-(b) of the mark for position detection. The top view which showed other examples (a)-(c) of the reference position detection mark.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Position detection mark 11 Position display part 12 Reference position detection mark 13 Position reading code 14 Moving body reference line 15 Height reference line 19 Installation reference position 20 Guide rail 30 Moving body 40 Camera controller 45 Camera 50 Motor controller 55 Moving motor 60 Crane controller 65 Crane 70 Control unit 80 Mark installation surface 100 Luggage transfer equipment

Claims (8)

For position detection comprising a reference position detection mark formed so that the boundary line intersects on a line passing through a predetermined reference position, the area having different colors and a plurality of boundary lines formed by contacting the areas A camera that moves and images the mark;
Color detection means for detecting colors on a plurality of scanning lines in a captured image of the position detection mark imaged by the camera;
An intersection position deriving means for obtaining an intersection position between the scanning line and the boundary line in the reference position detection mark based on a color change on the scanning line detected by the color detection means;
Boundary line deriving means for obtaining a plurality of the boundary lines from a plurality of intersection positions obtained by the intersection position deriving means;
Crossing position deriving means for obtaining a boundary crossing position where a plurality of the boundary lines obtained by the boundary line deriving means intersect;
A reference position specifying means for determining, as the line, a line connecting a plurality of boundary line intersection positions obtained by the intersection position deriving means, and specifying the reference position based on the line;
A position detecting device characterized by that. The position detection mark is further arranged with a predetermined distance from the reference position, and further includes a position reading code in which position information of the reference position is encoded,
A reading position setting means for setting a reading position of the position reading code using the reference position specified by the reference position specifying means;
Position information reading means for reading the position information displayed on the position reading code at the position set by the reading position setting means,
The position detection device according to claim 1. A deviation calculating means for calculating a deviation between a reference point in an image captured by the camera and the reference position;
Camera position detecting means for detecting the position of the camera based on the deviation calculated by the deviation calculating means and the position information read by the position information reading means;
The position detection apparatus according to claim 1 or 2, wherein A method for detecting a position of a moving object including a camera,
A position detection mark is formed on the camera by imaging the position detection mark, which includes an area having a different color and a plurality of boundary lines formed in contact with the area, and the boundary line intersects on a line passing through a predetermined reference position. An imaging step to
A color detection step of detecting colors on a plurality of scanning lines in a captured image of the position detection mark imaged in the imaging step;
An intersection position derivation step for obtaining an intersection position between the scanning line and the boundary line based on a change in color on the scanning line detected in the color detection step;
A boundary line deriving step for obtaining a plurality of boundary lines from a plurality of intersection positions determined in the intersection position deriving step;
An intersection position deriving step for obtaining a boundary line intersection position where a plurality of the boundary lines obtained in the boundary line deriving step intersect;
A reference position specifying step for determining a line connecting a plurality of boundary line intersection positions obtained in the intersection position deriving step as the line, and specifying the reference position based on the line;
A position detection method comprising: A reference position detection mark for detecting a predetermined reference position;
A position reading code in which position information of the reference position is encoded;
With
The reference position detection mark includes a plurality of regions having different colors,
A plurality of boundary lines formed by contacting different regions intersect on a line passing through the reference position.
A position detection mark characterized by that.   The position detection mark according to claim 5, wherein the position information is a distance from a predetermined position to the reference position.   7. The position detection mark according to claim 5, wherein the position reading code is a bar code.   The position detection mark according to claim 5, further comprising a position display unit expressing the position information with characters.

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