JP6402497B2 - Height detection device - Google Patents

Description

  The present invention relates to a height detection device that detects the height of an object from an image captured by a camera provided at a boom tip.

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

  In this crane surveillance camera device, a camera housing is attached to the tip of a boom, and a swing base is provided in the camera housing so as to be rotatable in the X-axis direction with the shaft as a fulcrum. A camera base is provided so as to be rotatable in the Y-axis direction as a fulcrum. A TV camera is fixed to the camera base, the swing base is rotated in the X-axis direction by a motor, and the camera base is rotated in the Y-axis direction by another motor, thereby photographing the area around the hook over a wide range. Be able to.

Japanese Patent Publication No. 8-15995

  By the way, in such a crane surveillance camera device, there is a problem that the height of an object cannot be obtained from a captured image. In order to solve this problem, a stereo camera may be provided. However, it is necessary to perform image processing on two images captured by the stereo camera. For this reason, an arithmetic process for obtaining the height is performed. There is a problem that the configuration becomes complicated.

  An object of the present invention is to provide a height detection apparatus that can determine the height of an object without performing image processing.

The invention of claim 1 includes a camera provided at the tip of the boom of the work implement and a monitor that displays an image captured by the camera, and obtains the height of the object displayed on the screen of the monitor. A height detection device,
Computation means for computing the height of the object based on the position corresponding to the lower end of the object displayed on the monitor screen , the position of the portion corresponding to the upper end of the object, and the height position of the camera is provided. It is characterized by that.

  According to the present invention, the height of an object can be obtained from an image captured by one camera without performing image processing.

It is the side view which showed the mobile crane carrying the working area line display apparatus which concerns on this invention. It is the block diagram which showed schematically the structure of the work area line display apparatus. It is explanatory drawing which showed the positional relationship of the optical center position of a surveillance camera, and a building. It is explanatory drawing which showed the principle which calculates | requires the height of a building. It is explanatory drawing which showed an example of the image displayed on a monitor when the monitoring camera is pointed directly below. It is explanatory drawing which showed the positional relationship of the optical axis, optical center, and building when a surveillance camera inclines. It is explanatory drawing which showed an example of the image displayed on a monitor when a surveillance camera inclines.

  Hereinafter, an embodiment as an embodiment of a height detection apparatus according to the present invention will be described with reference to the drawings.

[First embodiment]

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

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

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

  A sheave 23 (see FIG. 3A) is provided at the tip of the tip boom 16C. A wire rope 25 (hereinafter referred to as a wire) is hung on the sheave 23, and the hook block 19 is suspended by the wire 25. Yes. A hook 21 is attached to the hook block 19.

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

  A camera unit 30 is attached to the distal end portion of the distal end boom 16C.

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

  In the camera unit 30, a pan sensor S1 for detecting the tilt in the pan direction of the monitoring camera 32 and a tilt sensor S2 for detecting the tilt in the tilt direction are provided. The pan sensor S1 and the tilt sensor S2 detect the tilt angle of the monitoring camera 32 in the pan direction and the tilt direction with respect to the housing 31, but the housing 31 is directed directly downward due to its own weight. The tilt angle in the direction and the tilt direction is detected.

The tilt (orientation) of the surveillance camera 32 is adjusted by operating a pan switch (posture operation means) SW1 (see FIG. 2) and a tilt switch SW2 (posture operation means) of an operation unit (not shown) provided in the cabin 20. Is done by. The surveillance camera 32 zooms by operating the zoom switch SW3.
[Height detection device]

  FIG. 2 is a block diagram illustrating a configuration of a height detection apparatus 100 that detects the height of an object.

The height detection apparatus 100 includes a camera unit 30, a pan sensor S1 and a tilt sensor S2 that detect the tilt angle of the monitoring camera 32, a monitor 40 that displays an image captured by the monitoring camera 32, and a display screen of the monitor 40 ( A touch panel 41 attached to the touch panel 41 (not shown), a touch position detection sensor 42 that detects a touch position of the touch panel 41, a boom posture detection sensor 50, and a controller 60 are provided.
[Boom attitude detection sensor]

The boom posture detection sensor 50 detects the length and undulation angle of the telescopic boom 16, the turning angle of the telescopic boom 16, and the like, and has sensors (not shown) for detecting each.
[controller]

  The controller 60 includes a motor control unit 63 in addition to the camera height calculation unit 61 and the object height calculation unit (calculation unit) 62. The motor control unit 63 drives and controls the pan motor 33 and the tilt motor 34 based on the operation of the pan switch SW1 and the tilt switch SW2.

In addition, the controller 60 controls various cylinders (not shown) by operating an operation unit (not shown) provided in the cabin 20 so that the telescopic boom 16 can be expanded, undulated and swung. It has become.
[Camera height calculator]

The camera height calculation unit 61 includes a detection signal (length and undulation angle of the telescopic boom 16) detected by the boom posture detection sensor 50, an optical center point of the monitoring camera 32, and a sheave center point of the distal end portion of the telescopic boom 16. Based on the positional relationship, the height from the ground to the optical center point of the monitoring camera 32 is obtained. Since the positional relationship between the optical center point and the sheave center point at the tip of the telescopic boom 16 is known, it is input in advance to the camera height calculation unit 61 as camera position data.
[Object height calculator]

The object height calculation unit 62 calculates the height of the object based on the height from the ground obtained by the camera height calculation unit 61 to the optical center point of the monitoring camera 32 and the touch position of the touch panel 41. A position calculation unit (not shown) that calculates the positions of the lower and upper ends of an object image, which will be described later, based on the touch position of the touch panel 41 is provided. The object height calculation unit 62 also includes a reference position calculation unit (not shown) for obtaining a reference position E1 described later, and a reference image position GE1 on the screen of the monitor 40 corresponding to the reference position E1 (see FIG. 4). A coordinate position calculation unit (not shown) for obtaining Hereinafter, the principle for obtaining the height of the object will be described.
[Principle]

  As shown in FIGS. 3 and 3A, the height from the ground to the optical center point Q1 of the surveillance camera 32 is HGn, and the position of the ground F just below the optical center point Q1 is the reference position E1. When the monitoring camera 32 is directed directly below, assuming that the position on the screen 40G of the monitor 40 (see FIG. 4) corresponding to the reference position E1 in FIGS. 3 and 3A is the reference image position GE1, this reference image position GE1. Is the image center position GPa of the screen 40G.

  The height of the building (object) T captured by the surveillance camera 32 is H1, and the position of the edge (upper end) which is the boundary of the roof of the building T is P1, and this position P1 and the optical center point Q1 are The connecting straight line is L1, the position of the intersection of the straight line L1 and the ground F is P2, the distance between this position P2 and the reference position E1 is B, the lower end position of the building T is P3, and this position P3 and the reference When the distance between the position E1 is A, the straight line connecting the optical center point Q1 and the reference position E1 is L2, and the angle between the straight line L1 and the straight line L2 is θ, the wall Ta of the building T and the straight line L1 are formed. The angle is θ.

  As shown in FIGS. 3A and 4, the triangle having the vertexes at the optical center point Q1, the reference position E1, and the position P2 and the triangles having the vertexes at the positions P1, P2, and P3 are similar to each other. B = H1: (BA). As a result, H1 = HGn · (1−A / B).

  That is, if the height HGn and the distances A and B are known, the height of the building T can be obtained.

  The height HGn can be obtained as a value obtained by subtracting the offset amount W2 from the height H2 from the ground F to the central axis 23J of the sheave 23 at the tip of the telescopic boom 16 as shown in FIG. 3A. The height H2 can be obtained from the length and undulation angle of the telescopic boom 16, and the offset amount W2 knows the positional relationship between the sheave 23 and the surveillance camera 32. Therefore, if the undulation angle of the telescopic boom 16 is known, the offset amount W2 is obtained. Can be requested.

  Further, since the positions P2 and P3 shown in FIG. 3A are the intersections GP2 and GP3 of the building image GT displayed on the screen 40G of the monitor 40 as shown in FIG. 4, the distance A shown in FIG. Is the distance GA from the reference image position GE1 (GPa) on the screen 40G shown in FIG. 4 to the intersection GP3, and the distance B is the distance GB from the reference image position GE1 to the intersection GP2. The distances GA and GB are obtained as the number of pixels.

  Therefore, since the height HGn is known, the distances A and B can be obtained from the angle of view of the monitoring camera 32, the zoom magnification, and the number of pixels GA and GB on the screen 40G.

  When the surveillance camera 32 is tilted or panned, for example, as shown in FIG. 5, when the surveillance camera 32 is inclined with respect to the vertical line Lo by an angle α, the optical axis of the surveillance camera 32 is set to La. If the intersection of the optical axis La and the ground F is Pa, this intersection Pa becomes the image center position GPa of the screen 40G shown in FIG. In FIG. 5, the position immediately below the optical center point Q1 of the monitoring camera 32 is the reference position E1, and the separation distance D between the reference position E1 and the intersection Pa can be obtained by D = HGn · tan α.

  Therefore, as shown in FIG. 6, the position on the screen 40G that is separated from the image center position GPa (in FIG. 6) by the number of pixels GD corresponding to the distance D becomes the reference image position GE1.

If the distance (number of pixels) from the reference image position GE1 on the screen 40G to the intersections GP3 and GP2 is obtained, the height of the building T can be obtained in the same manner as described above.
[Operation]

  Next, the operation of the height detection apparatus 100 configured as described above will be described.

  Now, it is assumed that the surveillance camera 32 is pointed directly below, for example, the building T is imaged as shown in FIGS. 3 and 3A, and the screen 40G is displayed on the screen of the monitor 40 as shown in FIG.

  The boom posture detection sensor 50 shown in FIG. 2 detects the telescopic length and undulation angle of the telescopic boom 16 at this time, and the camera height calculation unit 61 of the controller 60 detects the detection signal of the boom posture detection sensor 50 and the monitoring camera 32. The height position HGn (see FIGS. 3 and 3A) of the monitoring camera 32 is obtained based on the mounting position and the like.

  On the other hand, the object height calculation unit 62 of the controller 60 determines that the monitoring camera 32 is directed directly below based on the detection signals detected by the pan sensor S1 and the tilt sensor S2, and the optical center point of the monitoring camera 32. A reference image position GE1 of the screen 40G of the monitor 40 corresponding to the reference position E1 directly below Q1 is obtained. When the monitoring camera 32 is pointed directly below, the reference image position GE1 is the image center position GPa of the screen 40G.

  Further, the object height calculation unit 62 displays a guideline N passing through the reference image position GE1 and extending in the extending direction of the telescopic boom 16 on the screen 40G of the monitor 40 as shown in FIG.

  The operator displays the boundary line image indicating the boundary line between the intersection line GP2 between the guideline N displayed on the monitor 40 and the boundary line image (upper end) GT1 indicating the boundary line on the roof of the building T and the ground F of the building T. (Lower end) Touch the intersection GP3 between GT2 and the guideline N via the touch panel 41. When the touch panel 41 is touched, the touched position detection sensor 42 detects the touched position.

  The object height calculation unit 62 calculates the number of pixels of the distances GA and GB shown in FIG. 4 based on the touch position detected by the touch position detection sensor 42, and the number of pixels GA and GB and the height HGn of the monitoring camera 32. Based on the above, the height H1 of the building T is obtained geometrically as described in the principle. This height H1 is displayed on the screen of the monitor 40.

As described above, the object height calculation unit 62 geometrically calculates the height of the building T based on the height position HGn of the monitoring camera 32 and the touch position detected by the touch position detection sensor 42. Therefore, no image processing is required, and the height of the object can be obtained from an image captured by one monitoring camera 32. Therefore, the configuration of the calculation processing of the object height calculation unit 62 is simple and inexpensive. The height detection apparatus 100 can be provided.
[When surveillance camera 32 is tilted or panned]

  As shown in FIG. 5, when the monitoring camera 32 is tilted and, for example, the optical axis La of the monitoring camera 32 is tilted at an angle α with respect to the vertical line Lo, the object height calculation unit 62 includes the pan sensor S1 and the tilt sensor. Based on the detection signal detected by S2, it is determined that the surveillance camera 32 is inclined at an angle α with respect to the vertical line. Then, the object height calculator 62 obtains the reference image position GE1 on the screen 40G of the monitor 40 corresponding to the reference position E1 directly below the optical center point Q1 of the monitoring camera 32 as described in principle, and this reference image The guideline N passing through the position GE1 and extending in the extending direction of the telescopic boom 16 is displayed on the screen 40G of the monitor 40 as shown in FIG.

  As shown in FIG. 6, the operator connects the guideline N displayed on the monitor 40 and the boundary line image (upper end) GT1 indicating the boundary line of the roof of the building T GT1 and the ground F of the building T to the ground F If the boundary line image (lower end) GT2 indicating the boundary line and the intersection GP3 of the guideline N are touched via the touch panel 41, the object height calculation unit 62 geometrically increases the height of the building T as described above. This is displayed on the monitor 40.

Thus, even when the surveillance camera 32 is tilted or panned, the height of the building T can be obtained geometrically, image processing is not required, and the image is taken by one surveillance camera 32. Since the height of the object can be obtained from the image, the configuration of the calculation processing of the object height calculation unit 62 is simple, and the inexpensive height detection apparatus 100 can be provided.
By the way, in the said Example, although the touch position of the touch panel 41 is made into intersection GP2 and GP3, the position of the outline of the image of the vicinity of the touch position is calculated | required by image recognition, The position of the outline close to the touch position You may obtain | require as GP2 and GP3. In this case, since only the image portion near the touch position needs to be image-processed, the image processing load can be reduced, and the accurate intersections GP2 and GP3 can be obtained, and the exact height of the building T can be obtained. Will be able to.
Further, in the case of a building T, the boundary line between the upper end and the lower end may be obtained by pattern recognition using the fact that the boundary line between the upper end and the lower end is parallel. In this case, since the position of the boundary line is known by image recognition, the positions of the intersections GP2 and GP3 can be obtained, and thus the touch panel 41 is not necessary. Also in this case, since pattern recognition is used, the image processing load is small, and the accurate height of the building can be obtained.
Furthermore, a cursor may be displayed on the display screen of the monitor 40, the cursor may be moved to the intersection positions GP2 and GP3, and the intersection positions GP2 and GP3 may be specified by the cursor and obtained. In this case, image recognition and the touch panel 41 are unnecessary.

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

10 Crane 16 Telescopic boom 32 Surveillance camera (camera)
40 Monitor 41 Touch Panel 50 Boom Attitude Detection Sensor 60 Controller 61 Camera Height Calculation Unit 62 Object Height Calculation Unit S1 Pan Sensor S2 Tilt Sensor SW1 Pan Switch (Attitude Operation Unit)
SW2 Tilt switch (Attitude control means)

Claims (4)

A height detection device that includes a camera provided at a tip of a boom of a work implement and a monitor that displays an image captured by the camera, and obtains the height of an object displayed on the screen of the monitor. ,
Computation means for computing the height of the object based on the position corresponding to the lower end of the object displayed on the monitor screen , the position of the portion corresponding to the upper end of the object, and the height position of the camera is provided. A height detecting device characterized by that. A touch panel provided on the screen of the monitor;
The calculating means, the position of the partial operator corresponding to the upper end portion and the object corresponding to the lower end of the object by touching the corresponding parts via the touch panel on the upper end of the lower end corresponding parts and the object of the object A position calculation unit for calculating the height of the object based on the position corresponding to the lower end of the object obtained by the position calculation unit, the position corresponding to the upper end of the object, and the height position of the camera. The height detecting device according to claim 1, wherein the height detecting device is obtained. A guideline that passes through the optical center position on the screen of the monitor corresponding to the reference position on the ground directly below the camera and extends in the same direction as the boom extension direction is displayed on the monitor,
The height detection apparatus according to claim 2, wherein the height of the object is obtained by touching an intersection between the guide line and a portion corresponding to the lower end of the object and a portion corresponding to the upper end of the object. Inclination angle detection means for detecting the inclination angle of the camera, and boom posture detection means for detecting the posture of the boom,
The calculation means includes a reference position calculation unit for obtaining the reference position based on the tilt angle of the camera detected by the tilt angle detection means and the boom length and undulation angle detected by the boom posture detection means, and the reference position A coordinate position calculation unit for obtaining a reference image position on the monitor screen corresponding to the reference position obtained by the calculation unit;
The height detection apparatus according to claim 3, wherein the guide line is displayed so as to pass through a reference image position obtained by the coordinate position calculation unit.