JPS59214703A - Position measuring device utilizing laser light - Google Patents

Abstract

PURPOSE:To perform highly accurate position measurement and angle deviation measurement of a target itself in realtime, by obtaining the position deviation and the angle deviation based on the coordinates of projected laser light positions detected by the first and second image pickup cameras, thereby eliminating the factors yielding mechanical errors in the main body of a target. CONSTITUTION:When a shield machine is deviated from the light axis of laser, a laser spot P1 of a first light receiving plate 2 is deviated from the center. Based on the values of X-Y coordinates at this time, the magnitude and the direction of the position deviation can be found. The laser spot P1 is sent to a synchronization controller 11 in an operation processing part 10 as a video output V1 from a first image pickup camera 4. The signal is operated and analyzed by a central processing part 12, and the X-Y coordinates are displayed on a display part 14a. Laser light (b) is projected on a second light receiving plate 3 through the semi-transmitting first light receiving plate 2. Like the laser spot P1 on the first light receiving plate 2, the position of a laser spot P2 on the second light receiving plate 3 is detected by a second image pickup camera 5, sent to the operation processing part 10 as a video signal V2, and displayed on a display device 14b as the X-Y coordinates through the synchronization controller 11 and the central processing part 12.

Description

[Detailed description of the invention]: 1) The technical field of the invention is to use laser light to create
Regarding the position measuring device for detecting positional deviations between PJTs, in particular, 1. During tunnel excavation work, a laser oscillator is installed at a base point such as the tunnel entrance, 1. The present invention relates to a position measuring device for detecting positional variations.

(2) Prior art and its problems Surveying to determine the relative position of two points is an indispensable task in linear outdoor construction work such as roads and pipelines, and in tunnel excavation work.

Compared to the former field work, methods such as traverse side measurements and triangulation cannot be used at the tunnel entrance of the latter, and there are constraints in size and space, and high measurement accuracy is required. measurement was extremely difficult.

In recent years, measuring instruments that use laser light have been widely adopted in the field of surveying, and even in tunnel excavation work, laser measuring instruments are used without exception, and the accuracy of position measurement has been dramatically improved. One method is the shield method, in which an armor cylinder (shield machine) is pushed forward in all excavation directions to excavate. A target is attached to the excavation machine located at the face ((), and a laser oscillator fixed at the tunnel entrance is used to excavate. Various devices have been proposed that measure the position by projecting a laser toward the target and detecting the attachment of the laser from the receiving position of the laser beam received by the target.

In a device in which photodiodes are arranged in a matrix in the laser receiving section of the target, the distance between adjacent elements is large, making it impossible to read the device at a position of about 3 m or less, and the accuracy is not satisfactory.

The device disclosed in Japanese Patent Application Laid-Open No. 57-63415 moves the laser receiving surface of the target in an orthogonal direction, observes the laser projection position on the receiving surface with a television camera, and determines the position attachment from the amount of deviation of the laser projection position. However, since a feed screw mechanism is used as a means for moving the laser receiving surface, a mechanical error that is far greater than the required measurement accuracy occurs.

However, a proposal using two light-receiving surfaces and a convex lens has been made, but measurement accuracy deteriorates due to the unavoidable problem of lens aberration.

Fourth, in Japanese Patent Application Laid-open No. 57-96213, a through hole is provided in the target, and the laser beam passing through the hole is reflected at a position distant from the target and returned to the back surface of the target. This device detects attachment, and this device doubles the positional displacement to improve accuracy.However, this method causes reflection distortion, and it is difficult to position the laser beam in a small hole in the target. It is difficult and troublesome. However, like the conventional example above, this device also uses mechanical elements to
Since it is moved in the fc optical axis direction, a non-negligible error occurs, resulting in poor accuracy.

In order to eliminate the above-mentioned drawbacks of the prior art, the applicant has already developed a highly accurate and easy-to-operate position measuring device (
(Patent Application No. 104209/1982).

This device places a target consisting of a laser light-receiving surface and a solid-state imaging camera on a continuously moving excavator, and uses the camera to detect the spot of laser light projected onto the light-receiving surface while moving the excavator to spot the laser beam. It is designed to require the position of the device to be installed. This device is different from the conventional method, which interrupts construction work and independently operates the drive system with mechanical errors to measure the position. Accuracy measurement can be expected.

However, like the conventional device, the applicant's device detects only the positioning relative to the reference point that oscillates the laser, but it also detects the angular displacement (visotinking, yawing) of the target itself with respect to the optical axis. I couldn't do that.

(3) Purpose of the Invention The present invention has been developed in view of the above-mentioned circumstances, and has a configuration that eliminates factors that cause mechanical errors in the target body, and allows extremely high-precision position measurement and the target itself. It is an object of the present invention to provide a position measuring device that can also perform angular deviations in real time.

(4) Features of the Invention In order to achieve the above object, the features of the present invention include providing a first light-transmissive light-receiving plate on one end of the target, a second light-receiving plate on the other end, and First and second imaging cameras are installed to image and detect the laser beam projected onto each of the two light receiving plates and read the laser receiving position, and the positioning and angular deviation are determined from the coordinates of the laser projection position detected by each camera. That's what I did. Embodiments of the present invention will be described below with reference to FIG.

(5) Practical drawings of the invention Fig. 1 is a schematic explanatory diagram of an actual Mh flll in which the position measuring device of the present invention is applied to tunnel excavation work, Fig. 2 is a partially cutaway perspective view of a target, Fig. 3 The figure is a usage state diagram.

1 out of 1 is a target that is mounted and fixed on a moving body such as an excavator. This target 1 is laser 9 incident 1)
A semi-transparent first light receiving plate 2 provided at 111, a second light receiving plate 3 disposed in parallel opposite to the first light receiving plate 2,
and a second light receiving plate 2. ,． A first and second imaging camera 4, 5 such as a CCD image sensor, which take an image of each of the images, are housed in a housing synchronizer.

In this embodiment, the first imaging camera 4 is connected to the second light receiving plate 3 so that the imaging directions of the first and second imaging cameras 4 and 5 intersect.
The second imaging camera 5 is positioned below the first light receiving plate 2 . Consideration is given to reducing parallax by placing both imaging cameras at positions out of their field of view, and at the same time making the angle of elevation toward the light-receiving plates that they face as small as possible. That is, as long as spatial constraints permit, both imaging cameras should be brought close to the light receiving plate where the VC is located, and both imaging cameras should be
It is desirable to make the distance l between the i camera and the light receiving plate as large as possible.

The imaging cameras 4 and 5 used here are compact, stable in operation, and employ CCD image sensors with excellent resolution. The coordinates at of the spot-like 17 laser projection points pl and p2 are expressed as video signals Vl and V2 by
Any means may be used as long as it has a function that can be used as an image sensor and has performance equivalent to or higher than that of a CCD image sensor.

Reference numeral 10 denotes an arithmetic processing unit that analyzes video signals Vl and V2 indicating laser projection position information from both imaging cameras 4 and 5 and displays the take. This arithmetic processing unit 10 includes a synchronous controller 11 that supports the synchronous side JA/D conversion function and buffer memory function of the cameras 4 and 5, and light receiving plates 2 and 3 based on the outputs Vl and V2 from the cameras 4 and 5. A medium heat processing unit (CPU) that calculates and outputs the laser spot position coordinates on the surface of the target 1 and the angular displacement of the target 1 itself based on them.
12, and a display device 13 for digitally displaying the output take from the CPU 12. This display device 13 displays each of the X-
It consists of buoy indicators 14a and 14b that indicate the y-coordinate value, an indicator 15 for the vertical angular displacement (pitching) of the target, and an indicator 17 for the horizontal angular displacement (yawing), and each indicator is equipped with a light emitting diode or the like. It can be displayed tentatively once a month.

Reference numeral 18 denotes a monitor TV that displays the images of the cameras 4 and 5. The laser spot can be monitored using the monitor TV 18, and the positions of the cameras 4 and 5 can be adjusted by remote control.

(6) Effects of the Invention The effects of the position measuring instrument having the above configuration and its application to shield method tunnel excavation work. Let me explain the case. As shown in Figure 3, a laser oscillator 7 is fixedly installed at a reference point near the tunnel entrance, and a laser beam is irradiated at the circular part of the tunnel where the excavation progresses.

The target 1 is attached to a cylindrical steel shield machine S located at the tunnel face, and the laser beam is projected onto the surface of the first light receiving plate 2 of the target 1. When proceeding with tunnel excavation, a base point position is determined as appropriate, and at that base point, for example, a laser beam is transmitted to the first light receiving plate 2.
The laser spot Pi on the surface of the first light receiving plate 2 is projected one after another while pushing the laser beam machine S forward.
is monitored by the first hoe camera 4 to detect the displacement of the laser spot P1. If the shield machine S moves forward in parallel with the optical axis of the nine lasers as designed, the positioning of the laser spot P1 will not be recognized. On the other hand, if the shield machine S deviates from the optical axis of the laser, the laser spot P1 of the first light receiving plate 2
deviates from the center, and the size and direction of the position can be determined from the X-Y coordinate values at that time. Laser spot P1
The video output V1 from the first imaging camera 4 is sent to the controller 11 with a period of 1 in the processing section 10, and then is processed and analyzed in the processing section 12 of Chuo University and displayed as X-Y coordinates on the display 14a. .

Laser light passes through the semi-transparent first light receiving plate 2'
Similarly to the laser spot Pi on the first light receiving plate 2, the laser spot P2 on the second light receiving plate 3 is also detected by the second imaging camera 5 and is output as a video signal 2. It is sent to the arithmetic processing section 10, passes through the synchronous controller 11 and the medium heat processing section 12, and then is sent to the display 14b.
are displayed as X-Y coordinates.

Now, if the target 1 is tilted at an angle with respect to the laser optical axis and maintains the pick angle deviation/position by 1, then the first.
The laser spot position on the second light-receiving plates 2 and 3 exhibits an irregular change in vector quantity with respect to the center. That is, when the tunneling machine shield S moves forward normally but the direction of advance is deviated, the longitudinal axis of the target 1 directly faces the laser oscillator 7 (FIG. 4). Therefore, the laser oscillator) PI, P2 on the light receiving plates 2 and 3 and the origin Ql on the light receiving plate,
Since the following relational expression is established from the respective lengths XI and X2 of 02, it can be recognized that the excavation direction θ is incorrect 9.

This is y! Regarding the displacement of the target and the X-Y coordinates, the vector quantities of these displacements also show the same regular relationship as in equation (1).

However, as conceptually shown in FIGS. 5A and 1 to 5C, when the vector quantity represented by the coordinates is irregular, it can be seen that the target has caused an angular deviation.

Figure 5 (laser oscillator on light receiving plates 2 and 3 in AJ')
The distances y 1 and y2 between pi, p2 and the origin Ql, 02 indicate the opposite positive and negative values. This example is a typical example of a vertical displacement (pitching) state, but has a displacement amount in the Y@ direction that does not satisfy the above equation (1) even if the values are of equal sign. In this case, target 1's ! l1Il] The slope of A can be expressed by the following formula.

-θ1-y″-y2 ・・・・・・・・・・・・・・・
(2) In Fig. 5(B), the distances XI, X2 between the laser spots Pl, P2 on both light receiving plates 2, 3 and the origin oi, 02
As can be seen, the axis A of the target 1 causes a deviation (yawing) in the water EF direction, and the inclination of the axis A in this case can be expressed by the following equation.

xl −x2 Theory θ2−□ ・・・・・・・・・・・・ +3) Guha,
Any angular deviation resulting from the combination of vertical and horizontal displacements from −θ1. This can be recognized by checking tanθ2.

1, Shield Machine S is causing an a-ring 1
The correctness of the measurement is guaranteed by inputting the take of #multipleI and correcting the above calculation result, which has been conventionally used. Since the inclinometer is not the gist of the present invention, its explanation will be omitted.

The angular displacement values based on the horizontal, vertical and rotational angle deviations are the first. Video output Vl of the second imaging cameras 4 and 5
, V2 to the arithmetic processing unit 10, and the loss processing unit ffTf1
The calculation is analyzed in step 2 and displayed on each display 15 and 17.

(7) As described in detail, according to the present invention, the semi-transparent first
A second light receiving plate is provided opposite to the light receiving plate; The first one images the projected laser spot on each of the second light receiving plates and detects the position. The second imaging camera is installed oppositely, and each camera detects the target itself, and the positioning device and angular deviation can be measured from the target position, allowing high-precision positioning without mechanical errors and the target itself. It is also possible to perform angular deviations in real time.

[Brief explanation of drawings]

Figure 1 is a schematic explanatory diagram of the position measuring device of the present invention;
The figure is a partially cutaway perspective view of the target, which is one element of the device, Figure 3 is a usage state diagram applied to tunnel excavation work, Figure 4 is an illustration of the analysis principle of position measurement, and Figure 5 (N~( B)
is a diagram explaining the principle of analysis of angular deviation. DESCRIPTION OF SYMBOLS 1... Target, 2... First light receiving plate, 3... Second light receiving plate, 4... First imaging camera, 5... Second imaging camera, 7... Laser oscillator. Patent applicant Yoshi Yoshi, patent attorney representing Hook Co., Ltd. 1) Haru Yoshi

Claims (1)

[Claims] In a position measuring device that projects a laser beam from a laser oscillator onto a target set at a distance, and detects the position of the projected light on the surface of the target light receiving plate, the position measurement device calculates the positional deviation. Fixed distance from the semi-transparent first light receiving plate! A 71st and a 71st light-receiving plate are provided at the other end facing each other, and a 71st and a 71-th light-receiving plate are provided to face each other; A position measuring device @ characterized in that two imaging cameras are provided to depict a target, and a positional deviation and an angular displacement are determined from the laser projection position detected by the first and second imaging cameras.