JP3834654B2 - Camera verification equipment for 3D image measurement for wave observation of model ships - Google Patents

Description

The present invention performs verification of camera constants (camera parameters) for a camera set in which two cameras are arranged side by side on the camera support base of a model ship reference truck in a long water tank so that three-dimensional image measurement can be performed. Related to the equipment.

  Conventionally, when three-dimensional flow field measurement is performed using two video cameras or the like, a fixed camera is used to move a reference point plate having a number of known reference points in the measurement space in the depth direction. The coordinates of each reference point are known from the measured value and the amount of movement. Then, by obtaining the center of gravity position of each reference point image from the captured image of the reference point by image analysis, the image coordinates can be known, and the camera constant is calculated using this method.

  By the way, it is difficult to verify the flow velocity in the depth direction with the conventional means as described above. In other words, when performing camera constant verification, the two camera points are placed side by side, and the reference point plate as a subject to be photographed by the camera is retracted away from the camera by the traverse device. Although the reference point plate has been photographed, such a conventional method requires a precise traverse device for appropriately retracting the reference point plate so that the reference point plate is not shaken. There is a defect that invites.

In the past, the procedure was to repeat the procedure of taking a picture after the reference point plate was retracted about several centimeters, and then the shaking of the plate had subsided. The work efficiency was reduced.
July 2002, published by Morikita Publishing Co., Ltd. PIV Handbook (Visibility Information Society) pp. 187-191

The problem to be solved is that it is generally difficult to realize, at a low cost, a means for moving the reference point plate as a subject with precision relative to the camera in camera verification.
That is, in manufacturing a traverse device for precisely moving the reference point plate over a long distance, a work with extremely high accuracy is required, resulting in a significant increase in cost.
Therefore, the present invention makes it possible to quickly and inexpensively verify the camera on the cart using the traveling function of the model ship quoted cart that can run along the long water tank, and to change the orientation of the camera. Therefore, it is an object to be able to perform a tank test of a model ship immediately after the verification of the camera.

  The present invention pays attention to the fact that there is a towing cart attached to a long water tank for testing a model ship as a cart that goes straight along a straight rail with high accuracy, and a camera is mounted on such a cart. By using this camera, it is possible to efficiently scrutinize a 3D image measurement camera at low cost by enabling sequential imaging of a large number of stepped vertical reference planes on a reference point plate installed beside the straight rail track. It is something that can be done.

  Each reference point of a large number of stepped vertical reference planes on the reference point plate standing and fixed on the track side of the straight rail is sequentially placed by a camera set mounted sideways on the carriage that runs along the straight rail. Since the photograph is taken, the reference point is photographed while moving forward or backward with respect to the camera set according to the level difference of each vertical reference plane, and the camera is analyzed by analyzing the photographed data thus obtained. The set will be properly tested. Since the reference point plate is fixed, each reference point on the vertical reference surface of the plate is always in a stable position, and the verification operation can be performed more quickly than in the case of the conventional reference point plate moving type. There are advantages.

As the device for moving the carriage along a linear rail, Runode be utilized those equipped to the long aquarium for model ship tests, compared to the camera test system using a conventional traverse device, significant assay cost Reduction is expected.
Since the camera directed to the side for verification can be adjusted downward after the verification, wave observation of the model ship by the camera can be performed quickly and accurately.

A three-dimensional image measurement camera set is mounted horizontally on a model ship quoting cart that runs on a straight rail along the long side of the long water tank, and a reference point plate erected on one side of the long water tank by the camera set since the cracking camera test row by photographing the reference point in the stepped each vertical reference plane, by adjusting the orientation of the camera set after test downwards, using the same camera set above model ship towing carriage The towed model ship will be able to conveniently observe the waves generated on the water surface in the long tank.

Figure 1 is a plan view schematically showing one embodiment of a three-dimensional image measurement camera test equipment of the present invention, FIG 2 is an A-A arrow view of FIG. 1, a camera support table in Figure 3 Figure 1 It is a top view which expands and shows the upper camera set.

  As shown in FIGS. 1 and 2, there is an electric model ship citation carriage 3 that can be placed and traveled on the left and right rails 2, 2 along the long side of the long water tank 1 so as to straddle the long water tank 1. A three-dimensional image measurement camera set 5 whose camera constants (camera parameters) are verified is mounted horizontally on the same carriage 3 via a camera support 4.

  As shown in FIG. 3, the camera set 5 on the camera support 4 is mounted on the movable beam 4a so that the left and right cameras 5a and 5b cross each other in the front along the same horizontal plane. It is constituted by.

  The movable beam 4a is screwed onto the male screw shaft 4c via the female screw portion 4b, and the movable beam 4a with the cameras 5a and 5b is driven as the male screw shaft 4c is rotated by an electric or manual rotation drive mechanism 4d. However, it is configured to be able to move forward or backward on the camera support 4.

As shown in FIGS. 1 and 2, the reference point plate 6 having a large number of vertical reference planes 6 a to 6 f photographed by the horizontal camera set 5 on the carriage 3 is arranged on the straight rail 2 on the side of the track of the straight rail 2. The vertical reference planes 6a to 6f are directed to the straight rail 2 side and are sequentially formed with a certain level step in the horizontal direction perpendicular to the straight rail 2. Each of the reference surfaces 6a to 6f is provided with a plurality of reference points 7 as subjects having a fixed position and a mutual interval.

In this way, the two cameras 5a are mounted on the camera support 4 of the carriage 3 that runs on the rail 2 at right angles to the direction in which the reference surfaces 6a to 6f of the reference point plate 6 are directed. , 5b are provided so that their positions can be adjusted in the horizontal direction perpendicular to the straight rail 2 by rotational driving of the male screw shaft 4c while maintaining their relative postures.

When the cameras 5a and 5b are video cameras, the video camera is set so as to continue photographing until it reaches the other side end from one side end of the reference point plate 6 in the traveling state of the carriage 3.
When the cameras 5a and 5b are still cameras, the shutter is set to operate when the still camera is directed to the center of each of the reference surfaces 6a to 6f of the reference point plate 6 in the traveling state of the carriage 3. Has been.

  In the above-described three-dimensional image measurement camera verification facility of the present embodiment, each reference point of a large number of vertical reference surfaces 6a to 6f with steps in the reference point plate 6 standingly fixed on the side of the line of the straight rail 2 is provided. 7 are sequentially photographed by the camera set 5 mounted sideways on the carriage 3 traveling along the straight rail 2, so that the reference point 7 is placed on the camera set 5 according to the steps of the vertical reference planes 6a to 6f. On the other hand, the image is taken while moving forward or backward, and the camera set 5 is accurately verified by analyzing the obtained photographing data. Since the reference point plate 6 is fixed, each reference point 7 on the vertical reference planes 6a to 6f on the plate 6 is always in a stable position, which is compared with the conventional reference point plate moving type. There is an advantage that work can be done quickly.

  Further, when the step between adjacent reference planes in the reference point plate 6 is ΔL, the two cameras 5a and 5b use the rotational drive mechanism 4d in a direction perpendicular to the straight rail 2 on the camera support base 4, For example, by adjusting the movement by ΔL / 2, it is possible to obtain an advantage that a detailed image can be collected in two runs of the carriage 3.

Further, as an apparatus for running the carriage 3 along the straight rail 2, as compared Runode be utilized those equipped to the long aquarium for model ship tests, a camera test system using a conventional traverse device, the test cost A drastic reduction of is expected.

Then, a three-dimensional image measurement camera set 5 is mounted sideways on a model ship citation carriage 3 that runs on a straight rail 2 along the long side of the long water tank 1, and the camera set 5 moves the camera tank 5 to one side of the long water tank 1. camera test by photographing the reference point 7 in stepped each vertical reference plane 6a~6f reference point plate 6 provided upright is to divide the line, by adjusting the orientation of the camera set 5 after test downward Thus, it is possible to conveniently observe the waves generated in the long tank 1 by the model ship towed by the model ship anchor trolley 3. When observing this wave, an operation is performed in which the carriage 3 travels while the measurement particles are dispersed on the water surface, and the particles are photographed by the camera set 5.

  By forming an image with a large number of colored reference points on each reference surface provided with steps on the reference point plate, it can also be used to produce an animated movie (moving picture).

It is a top view which shows typically one Example of the camera verification equipment for the three-dimensional image measurement for the wave observation of the model ship of this invention. It is an AA arrow line view of FIG. It is a top view which expands and shows the camera set on the camera support stand in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Long water tank 2 Straight rail 3 Model ship quote trolley 4 Camera support stand 4a Movable beam 4b Female thread part 4c Male screw shaft 4d Rotation drive mechanism 5 Camera set for 3D image measurement 5a, 5b Camera 6 Reference point plates 6a-6 f Vertical reference Surface 7 reference point

Claims (3)

In order to test the camera constants of a camera set for 3D image measurement in which two cameras are mounted on the camera support so that each optical axis crosses the optical axis in the front along the same horizontal plane, the camera support is turned horizontally and horizontally. A dolly that can be mounted on and fixed to a horizontal straight rail, and a reference that is erected and fixed parallel to the straight rail on the side of the straight rail track so that it can be photographed by the camera set on the dolly A plurality of vertical reference planes directed toward the straight rails, each of which is formed with a certain level step in a horizontal direction perpendicular to the direction of the straight rails. in which the reference point as a number of the subject is provided with a fixed position and mutual spacing, is configured as a model ship towing carriage which can travel on rails above bogie along the long sides of the long water bath, the Junten plates have been along upright at one side of the long side of the long water bath so as to direct the vertical reference plane the long water tank side, while the two cameras holds the relative orientation of the cross the camera supported on the platform in the straight line rail and is provided to be positioned horizontally adjustable at right angles Rutotomoni camera set of the two cameras after assay the observation of the wave causing the model ship in the long aquarium A camera verification facility for 3D image measurement for wave observation of a model ship , characterized in that the camera set is provided so as to be adjustable downward . The camera is a video camera, and the video camera is set so as to continue photographing from one side end to the other side end of the reference point plate in a traveling state of the carriage. Item 3. Camera verification equipment for three-dimensional image measurement for wave observation of a model ship according to item 1 . The camera is a still camera, and the camera is set to operate a shutter when the camera is directed to the center of each vertical reference plane in the reference point plate in the traveling state of the carriage. The camera verification equipment for three-dimensional image measurement for wave observation of a model ship according to claim 1 .

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