JPH0245711A - Three-dimensional measuring device - Google Patents

Abstract

PURPOSE:To measure a large-sized structure with high accuracy by attaching an observation device to a telescope, incorporating a signal from the observation device in an image processor, automatically obtaining a deviation angle from a target in the direction of the telescope and performing three-dimensional calculation. CONSTITUTION:The visual field image of an altazimuth I which is made to turn to a nearly target direction is displayed on a monitor 8-2 through the image pickup device 8-1 of the observation device II and focusing and aiming are performed on the monitor. Next, image information is transmitted from the device 8-1 to the frame memory 9-1 of the image processor III and the deviation between the direction of the telescope 1 of the altazimuth I and the target is obtained from the target position for the center of a visual field by using an image operation device 9-2. Then, the obtained result and the read value of an elevation angle and an azimuth by the encoders 3 and 4 of the altazimuth I are transmitted to a distance calculation device IV so as to calculate the correction angle for aiming and to obtain the three- dimensional position of the target or the driving quantity of a fine adjustment mechanism 10 provided in the elevation angle and the azimuth of the telescope 1. Thus, the large-sized structure can be measured with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to the enhancement and automation of an optical measuring device that measures the three-dimensional position of a structure.

(Prior art) In recent years, there has been an increasing demand for three-dimensional shape measurement of large structures, and three-dimensional coordinate measuring instruments using three-wheeled or multi-jointed stylus have been developed. Due to the limited dimensions, measurements of large structures require large equipment.

On the other hand, due to the simplicity of the device and the fact that there is no need to set an upper limit on the dimensions of the object to be measured, the measurement accuracy of the theodolites, which have been used in civil engineering surveying, has been improved and a method has been adopted for measuring the dimensions of structures. It's here.

Measurement of large structures using a theodolite (Fig. 2), which is a combination of a telescope and a two-axis angle measuring device for azimuth (Az) and elevation (El), is performed according to the following procedure.

First, we set up two theodolites with an appropriate distance between them 6-1.
6-2 (Fig. 3), and use a spirit level to adjust the rotation axis E.
Adjust so that 1 matches the vertical direction.

Next, align the optical axes of the telescopes of both theodolites and record the values of Az and El (for accuracy, flip the telescopes around the Az axis and face them directly again).

Now, move the Z axis, zx, upward from the vertical axis with the point 6-1 as the origin.
The spatial coordinate axis that takes point 6-2 on the plane is determined, and the relationship between the Az scales between the two theodolites is determined (Fig. 3-a).
).

The error in determining the spatial coordinate system becomes a bias component in subsequent angle measurements.

Furthermore, two points (7-1
, 7-2).

At this time, vector β1J from 7-i to 6-j=
-α1J, this corresponds to measuring the position of each theodolite based on 7-1.7-2, and the distance between the two theodolites (baseline length C) is calculated. Based on the direction of the coordinate system and the length of the base line, calibration for converting angle measurements into spatial coordinate values is performed (FIG. 3-b).

That is, this corresponds to measuring 6-1.6-2 with a positional accuracy of measurement accuracy m based on the interval S of 7-1.7-2, which causes an identification error of base line length C. This error propagates linearly, so if a system that can measure two points 2 m apart with an error equivalent to 0.2 mm is set at 5 m intervals, a 0.5 mm error will occur in the identification of the baseline length, and the following measurement Then, the measured value (
All coordinate values) include an error of 1710000 as a bias.

Thereafter, the two theodolites are focused and aimed at the target, and the spatial coordinate position of the target is calculated as the point that is the shortest distance from the two vectors formed by the angle (El, Az) including the measurement error (3rd Figure-C).

Measurement accuracy is specified below.

Similarly to (1), in Fig. 4-a, when the baseline length is C, the measurement position degree mp is expressed as the angle measurement accuracy m, and when the object is on a perpendicular line passing through the midpoint of the baseline, becomes.

At this time, as shown in Figure 4-b, depending on the position of the object with respect to the two theodolites, the overall accuracy of the three-dimensional coordinate values δ (= dx2 + dy2 + dz2) even when measured with the same angle measurement accuracy.
) changes. The error is at its minimum when the angle θ viewing the two theodolites is around 110°, and when it is between 78° and 142°, the drop in accumulation is within a stone's worth.

(Problems to be Solved by the Invention) As described above, in position measurement using the latitude and longitude λ, target acquisition (coarse focusing, coarse aiming), The steps of focusing and aiming are required. At this time, the accuracy of the theodolite installation and aiming have a strong influence on measurement accuracy, but since focusing and aiming are still done visually, individual differences are unavoidable, and if the number of measurements is increased. It was an extremely difficult task.

In addition, especially when highly accurate measurement is required, calibration must be performed accurately, and the adjustment work before measurement becomes a heavy burden.

An object of the present invention is to provide an apparatus that performs non-contact measurement of large structures with high precision and efficiency.

(Means for Solving the Problems) A feature of the present invention for achieving the above object is that in a three-dimensional measuring device that measures the three-dimensional position of an object using a theodolite, the theodolite measures the elevation angle and azimuth angle of a telescope. An observation device equipped with an imaging device and a monitor, which is equipped with a fine movement mechanism that adjusts the telescope using an external signal, and a means for outputting the elevation angle and azimuth angle of the telescope to an external device, and which extracts the telescope image of the theodolite as image information. an image processing device that calculates a deviation between the pointing direction of the telescope and the target direction from the image information; and an image processing device that calculates a correction angle of the pointing direction of the telescope according to the deviation and corrects the pointing direction of the telescope via the fine movement mechanism. A three-dimensional measuring device is provided with a calculation means for calculating.

(Function) According to the above configuration, in a theodolite used for three-dimensional non-contact measurement of structures, by attaching an observation device to a telescope, observation can be made on a monitor screen, and signals from the observation device can be imaged. The data is imported into a processing device, the deviation angle of the telescope pointing direction from the target is automatically determined, and three-dimensional coordinate values are calculated. Therefore, non-contact measurement of the three-dimensional position of a large structure can be performed with high precision and efficiency without individual differences.

(Example) In Fig. 1, a fine movement mechanism is installed in the elevation angle and azimuth angle of the telescope for a theodolite that outputs the reading angle to a computer using an encoder to calculate the distance, and a solid-state image sensor is placed in the eyepiece to monitor it. An example of the configuration of a measurement system is shown in which an image processing device with a frame memory is connected to the image processing system.

In Figure 1, engineering is a theodolite with telescope 1 and encoder 3.
, 4, and a telescope fine movement mechanism 10. ■ is an observation device, which is an imaging device 8-1 that converts the telescope image into an electrical signal.
and a visual field image device 8-2 for monitoring the converted image on a screen. 2 is an image processing device, which has a frame memory 9-1 and an image calculation device 9-2, and outputs an error in the direction of the telescope. ■ is a distance calculation device that has a monitor l-1 that displays angles and distances and a calculator 11-2;
A driving amount of the telescope is given to correct the error.

Display the visual field image of the theodolite (I) pointing roughly in the direction of the target on the monitor (8-2) of the observation device (II), perform focusing and aiming on the monitor, and ) sends image information to the frame memory (9-1) of the image processing device (m), and uses the image processing device (9-2) to determine the direction of the theodolite telescope (1) from the target position relative to the center of the field of view. and the target, and compare the result with the theodolite encoder (3, 4).
) and the elevation and azimuth readings from the distance calculation device (
mV) and calculates the correction angle of the sight to determine the three-dimensional position of the target or the amount of drive of the fine movement mechanism (10) provided at the elevation and azimuth angles of the telescope.

For high-precision measurements, the fine movement mechanism is driven according to the correction angle of the sight, and the distance is calculated after the target is aligned with the center of the field of view.

As a result, the workload is reduced because visual inspection of the telescope field of view is no longer necessary, and the target can be sighted on the monitor, making it unnecessary to correct the sight, improving measurement efficiency. , it is possible to perform highly accurate measurements that eliminate individual differences.

(Effects of the Invention) As explained above, by using the three-dimensional measuring device according to the present invention, the accuracy and workability of measuring the position and shape of the components of large structures are improved. The shape of the fuselage can be measured in a short time, making assembly and adjustment easier.

In addition, high precision can be achieved by making the magnification of the telescope of the theodolite of this device variable, with a low magnification when capturing a target and a high magnification when aiming finely.

Furthermore, by adding an automatic focusing mechanism, counter-automatic measurement that only performs target acquisition becomes possible, resulting in labor savings.

If used in an optical measurement telescope that has a telescope and requires the object to be measured to be placed in the center of the field of view, various measurement settings can be made efficiently.

[Brief explanation of the drawing]

Fig. 1 shows an example of the configuration of a three-dimensional measuring device according to the present invention, Fig. 2 shows an example of a conventional theodolite, Fig. 3 shows the flow of three-dimensional measurement using a theodolite, and Fig. 4 shows a theodolite. It is a figure explaining the precision of three-dimensional measurement using. 1... Telescope, 2... El (elevation angle)
Axis, 3...El axis encoder, 4...Az axis encoder, 5...Az axis, 6-1.6-2...
・Theodolite position, 7-1.7-2...Target position, 8-
1... Imaging device, 8-2.・・Monitor, 9
-1... Frame memory, 9-2... Image calculation device, 10... Fine movement mechanism, 11-1... Monitor,
11-2...Calculator, ■...Theodolite,
■...Observation device, ■...Image processing device, ■...
・Distance calculation device, mp...Position accuracy, mr...
・Angular accuracy, S...Target spacing, C...Theodolite spacing, α1J...Vector from theodolite to target, β1
J: Vector of the theodolite from the target, θ: Angle looking into the theodolite, φ, ψ: Angle indicating the direction of α. V------11-co

Claims (1)

[Scope of Claims] A three-dimensional measuring device that measures the three-dimensional position of an object using a theodolite, wherein the theodolite has a fine movement mechanism that adjusts the elevation angle and azimuth angle of the telescope using an external signal, and a fine movement mechanism that adjusts the elevation angle and azimuth angle of the telescope. an observation device equipped with an imaging device and a monitor that outputs an image taken by the telescope of the theodolite to an external device as image information; A three-dimensional system, characterized in that it is equipped with an image processing device that calculates the deviation, and a calculation means that calculates a correction angle of the pointing direction of the telescope according to the deviation and corrects the pointing direction of the telescope via the fine movement mechanism. Measuring device.