JPH047806B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention projects a large number of spot lights onto an excavation surface, images them at a position away from the projector, and measures the unevenness of the excavation surface as the amount of displacement on the imaging surface. The present invention relates to an excavation surface shape measuring device that measures the three-dimensional shape of an excavation cross section in a non-contact manner without having a movable part.

Conventionally, methods for measuring the finishing accuracy of excavated surfaces such as large underground cavities or tunnel cross sections include measuring by directly touching the cross section using a scale or telescopic rod.
Non-contact measurement methods have been put into practical use, such as the rangefinder goniometer method and the photocopy method using a surveying camera.

Among these, the rangefinder goniometer method is a method in which a cross section is displayed by projecting slit light, and coordinates are obtained by measuring and calculating angles and distances at arbitrary intervals on the light beam in the cross section. For this reason, measurement requires manpower, and large cross-sections cannot be measured in a short time. Furthermore, the photocopy method requires photographic processing and processing using a plotting machine, and cannot output measurement results immediately.

The present invention has been made for the purpose of solving these drawbacks and providing a measuring device for measuring the shape of an excavated surface that can be measured immediately without an operator and that can serve as the eyes of a robot such as an automatic excavator. It is.

According to the excavation surface shape measuring device of the present invention, a projector is installed in front of an uneven surface such as an excavation surface and projects a large number of spots onto the surface to create a light spot on a cross section, and a projector is installed at a distance from the projector. A video camera is installed at It consists of a computer that calculates the amount of deviation from the position of a reference light spot on the imaging surface that is created when projected from a projector, and calculates the amount of relative displacement between the uneven surface and the virtual plane.

Now, with the principal point of the video camera lens as the reference point,
The line connecting the video camera and the projector is the X-axis, the lens optical axis from the reference point is the Z-axis, the axis passing through the reference point in a direction perpendicular to the X-axis and the Z-axis is the Y-axis, and the Z-axis is the line connecting the video camera and the projector. A plane parallel to the XY plane that is distant from the reference point on the axis is defined as a virtual plane. Then, since the position of the light spot on the virtual plane is known because it is a design point, a computer can perform geometric calculations, and the plane position on the imaging plane for each light spot on the virtual plane can be calculated. You can ask for it.

As described above, since a three-dimensional shape can be determined using a means that does not have a moving part such as a beam, measurement can be performed immediately and in a short time, and automatic excavation work can be performed. Furthermore, it can be used unattended in the harsh environment of tunnels and is not affected by vibrations. Since the measurement point is the position of the spot light and does not move like a beam, data processing after measurement is easy, and computer software can be created simply and easily.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Figure 1 is an overall schematic diagram of the component equipment and measurement method, in which 1 is a projector that projects a light spot, 2 is a video camera for imaging, 3 is a computer that processes image data, and 4 is a calculation. A computer peripheral device that outputs processing results, and consists of printers, displays, plotters, etc. Also 5
represents the target excavation surface, and 6 represents a light spot on the excavation surface.

2A is a plan view of the measurement principle, and FIG. 2B is a side view. In the figure, 7 represents a virtual plane, and 8 represents an imaging plane of a camera.

The three-dimensional coordinate reference point 0,0,0 is the position of the lens principal point of the video camera, and the X axis connecting the lens principal point and the projector is the Z axis, and the lens optical axis from the lens principal point is the Z axis.
The axis passing through the principal point of the lens in the height direction perpendicular to the X-axis and Z-axis is the Y-axis, and the plane parallel to the X-Y plane at a certain distance K from the camera on the Z-axis is a virtual plane.

Figures 3a and 3b are auxiliary views for determining the light spot position on the virtual plane, a is the X-Z plane view, and b is the Y-Z plane view.
-Z plan view.

In the figure O...Camera position T...Projector position S...Intersection point K between the camera's imaging plane and the Z axis...Intersection H between the virtual plane and the Z axis...Light spot position H' on the virtual plane... ...Light spot position L on the imaging surface of the camera...Distance between O point and T point M...Distance between O point and S point N...Distance between O point and K point, from point H to X , if the intersection points of the perpendicular lines drawn to the Y axis are I and J, respectively, then from Figure 3 a, △HIO
△OSH′ ∴:=:′ ′=(×)/ Also, from Figure 3 b, △HJO∽△OSH′ ∴:=:′ ′=(×)/ Light spot position on the virtual plane, light on the imaging surface Letting the point positions be (Kx, Ky, Kz) and (Sx, Sy, Sz), respectively, Sx=-(Kx, M)/N Sz=-M Sy=-(Kz×M)/N.

Since the light spot position on the virtual plane is known,
The plane position on the imaging surface corresponding to the light spot on the virtual plane is determined by calculation.

The calculation to obtain the three-dimensional shape of the excavation surface is shown below.

(1) Find the X and Z coordinates.

In the plan view of Figure 2a, there are two excavation surface positions that require calculation: one is far away from the virtual plane, and the other is near.
As shown in FIG.

In either case, the following six cases require calculation.

Case: The light spot on the excavation surface is on the left side of the projector Case: The light spot on the excavation surface is in front of the projector Case: The light spot on the excavation surface is between the projector and camera If there is.

Case: The light spot on the excavation surface is in front of the camera. Case: The light spot on the virtual plane is in front of the camera. Case: The light spot on the excavation surface is on the right side of the projector. In Figure 4, A ₁ to ₆ : Light points on the excavation surface H ₁ to ₆ : Light points on the virtual surface A' ₁ to ₆ : Light points on the imaging surface The auxiliary diagram for calculation in these six cases is shown in Fig. 4. This is shown in FIGS. 6 to 11. In the figure, the intersection of the line segment connecting the light point A on the excavation surface and the camera position (reference origin) with the virtual plane is B, and the intersection of the perpendicular lines drawn from points A, H, and B onto the virtual plane X-axis is C, D,
Assuming E and F, △BOF∽△OA′S :=:′ =(×′)/ △HOE∽△OH′S :=:′ =(×′)/ = ∴=(′−′)×/ = Also ΔAHB∽ΔATO :=: …(1) ΔACH∽ΔADT :=: …(2) ∴：=: =+− Therefore ={×(−)}/−) = ∴=+ ={×( −)}/ (−)={×(−)} /(−) Furthermore, from (1) and (2):=:=
+ Therefore = (×)/(-) ∴=(×)/(-) = (×)/(-) The light spot position on the excavation surface and the light spot position on the imaging surface are respectively (X, Y, Z ), (x, y, z), and by substituting known values and considering the positive and negative depending on the quadrant, we get: X=L・N・x/{L・M−N(Sx−x)} [Z]L・M·N/{L·M−N(Sx−x)} The above calculation can be similarly obtained for the case ~. The results are shown in FIG.

In Fig. 5, A ₁ to ₆ : Light points on the excavation surface H ₁ to ₆ : Light points on the virtual plane A' ₁ to ₆ : Light points on the imaging surface Auxiliary diagrams for calculations in these six cases are shown below. This is shown in FIGS. 12 to 17. Light spot A on the excavation surface
The intersection point on the x-axis is E, and the line segment connecting point A, T point, and O point is extended and the intersection point with the virtual plane is H.
I, H, Drop a perpendicular line from I on the x-axis, and let the intersections of the line segment parallel to the x-axis passing through point A be B and C, and the intersections with the x-axis be E and F, then ΔIOF∽ΔOA′ S :=:′ =(×′)/ ΔHOE∽ΔOH′S :=:′ =(×′)/ = ∴={×(′−′)} ／= Also, ΔIAC∽ΔIOF :=: ……(3 ) ΔHAB∽ΔHTE :=: =,= ∴:=: (+):= :(-) ={×(-)} /(-+)= =- ∴=-{×(-)} /(- +) Furthermore, from (3) =(×)/ ={×(+)}/ =-= ∴={×(--)}/ =(×)/ Light spot position on the excavation surface, on the imaging surface Letting the light spot positions be (X, Y, Z) and (x, y, z), respectively, and substituting known values and considering the positive and negative depending on the quadrant, X = -L・N・x/{L・M+N( x-Sx)} Z=L・M・N/{(L・M+N(x-Sx)} The above calculation can be similarly obtained for the case ~. The results are shown in FIG.

From the above results, the X and Z coordinates of the light spot position on the excavation surface are: −N{Sx−x)} (2) Find the Y coordinate.

As shown in Figure 3b, since the projector and camera are on the x-axis, the y-coordinate of the imaging plane relative to the light point on the virtual plane and the excavation There is no deviation from the y-coordinate of the imaging surface relative to the light spot on the surface.

An auxiliary diagram for calculation is shown in FIG.

If B is the intersection of the perpendicular lines drawn from point A to the Y axis, then ΔA′SO∽ΔOBA ′:=: ∴=(′×)/ Substitute the calculation result in section (1) and find the excavation surface. The light spot position on the top and the light spot position on the imaging surface are respectively (X,
Y, Z), (x, y, z), and considering the positive and negative depending on the quadrant, Y=[-y・(L・M・N) /{L・M−N(Sx−x)}]/M =-L・N・y/{L・M−N(Sx−x)} Therefore, by setting a virtual plane at a certain distance from the video camera, it is possible to calculate the unevenness of the excavation surface. can. FIG. 19 is a block diagram of the component equipment, including a spot light irradiation unit 1 consisting of a projector, an image input unit 2 consisting of a video camera, an arithmetic unit 3 consisting of a computer, and an image processing data output unit 4 which is a computer peripheral device. It's getting more familiar. Computer 3 is central control unit 3
1. It consists of a main storage device 32, a porcelain disk 33, a floppy disk 34, an image memory 35, etc., and the computer peripheral equipment 4 includes a printer 41, a plotter 42, and an image display 43.
It's getting more familiar.

Figure 20 is a flowchart showing the operating procedure.
The operating procedure will be explained with reference to this flowchart and the block diagram of the component equipment shown in FIG.

Before starting, the projector and video camera are positioned (step S ₁ ) and the virtual plane is set (step S ₂ ) as advance preparations. Once the preliminary preparations are completed, the projector illuminates the spot light (step _S3 ).
A video camera captures the spot light on the excavation surface (step _S4 ). The computer performs image processing such as binarization (step _S5 ), imports the data into the storage device (step _S6 ), and calculates the deviation between the basic coordinates of the virtual plane and the spot light on the excavation surface based on the data (step S6). Step _S7 ), and the unevenness of the excavated surface is grasped by arithmetic processing (Step _S8 ). The data converted into binary data from the computer, the coordinates of the spot light, and the calculated unevenness information of the excavation surface are input to the computer peripheral equipment, and are used for printer printing (step S ₉ ), display display (step S ₁₀ ), and plotter drawing (step S 10 ). _S11 )
etc., and the measurement work is completed. At this time, the calculation by the computer is of course performed based on the above-mentioned calculation formula.

As explained above, the present invention irradiates a large number of spot lights from a projector onto an uneven surface such as an excavation surface, and images the spots at a position away from the projector. The amount of displacement between the plane position and the plane position of the imaging surface of the light spot obtained by imaging the light spot that is created when projected by a projector onto a virtual plane set at a known distance stored by a computer. Since the three-dimensional shape of the target surface is measured by calculating the deviation between the target surface and the virtual plane using a computer, it can be measured unattended and immediately, and can be used as the eyes of robots such as automatic excavators. It is something that can play a role.

[Brief explanation of drawings]

Figure 1 is an overall schematic diagram of the excavation surface shape measuring device.
Figures 2a and b are a plan view and side view of the measurement principle, Figures 3a and b are auxiliary views for determining the light spot position on a virtual plane, a is an X-Z plan view, and b is a Y-Z plan view. A plan view, Fig. 4 is a plan view of the measurement principle when the position of the excavation surface that requires calculation is far from the virtual plane in the plan view of Fig. 2 a, and Fig. 5 is a plan view of Fig. 2 a. A plan view of the measurement principle when the excavation surface position that requires calculation is closer than the virtual plane,
Figures 6 to 11 are auxiliary diagrams for calculations in 6 cases in Figure 4, Figures 12 to 17 are auxiliary diagrams for calculations in 6 cases in Figure 5, and Figures 18a and b. are auxiliary diagrams for coordinate calculation, Figure 19 is a block diagram of the device, Figure 20 is a flowchart showing the operating procedure, and Figure 2
FIG. 1 is a list of calculation results when the excavation surface is farther from the virtual plane, and FIG. 22 is a list of calculation results when the excavation surface is closer than the virtual plane. 1...Projector, 2...Video camera, 3...Computer, 4...Computer peripheral equipment, 5...
...Target excavation surface, 6... Light spot on the excavation surface.

Claims (1)

[Claims] 1. A projector that is installed in front of an uneven surface such as an excavation surface and projects a large number of spots onto the surface to create a light spot on the cross section, and a video that is installed away from the projector and images the light spot on the cross section. A reference light that is created when projected from a projector onto a virtual plane that is set at a known distance from the position of the light spot on the imaging surface obtained by imaging a light spot on a cross section with a camera and the video camera. 1. An excavation surface shape measuring device comprising a computer that calculates the amount of deviation from the position of a point on an imaging surface and calculates the amount of relative displacement between an uneven surface and a virtual plane.