JPH0740066B2 - Method and device for measuring angle in three-dimensional space using laser beam - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method and apparatus for measuring a three-dimensional position using a laser beam, and more specifically, measuring an angle formed by a predetermined point in a three-dimensional space from a reference point. Method and device.

[Prior Art] Distance or direction measurement using a laser beam does not require heat kneading as compared with surveying by transit, and measurement data can be processed by a computer, and automatic recording or display is also possible. It is a surveying method. Therefore, the applicant of the present invention has proposed a superior measurement method using this laser beam in Japanese Patent Application No.
-189688 (see Japanese Patent Publication No. 3-58646), Japanese Patent Application No. 60
No. 267481 (see Japanese Patent Publication No. 4-11806).

By the way, all of the above-mentioned proposed measuring methods or devices measure an angle or direction of a predetermined point on the plane, that is, the measuring point is the reference point, and cannot measure the direction of the measuring point in the three-dimensional space. In addition, since the laser used for measurement has a beam shape, the measurement range is narrow. Of course, the beam shape does not cause any particular problem in measuring the plane position, but there is a problem in measuring the direction of the measurement point in the three-dimensional space.

OBJECT OF THE INVENTION Accordingly, the present invention aims to provide a method and apparatus for measuring the direction of a measurement point in a three-dimensional space from a reference line using a laser, and to perform measurement with an expanded measurement range. It is an object to provide a method and a device.

[Structure of the Invention] According to the angle measuring method in the three-dimensional space using the laser beam according to the present invention, 2 on the X and Y planes with predetermined intervals.
A first laser lighthouse for rotating and irradiating a slit-shaped laser beam around the Z axis perpendicular to the X and Y planes at the same speed in opposite directions to each other is installed at one of the reference points of the points, and at the other of the reference points. A second laser lighthouse which is located at the reference point in the X and Y planes and which rotatably irradiates a slit-shaped laser beam around the X axis orthogonal to the Z axis as in the first laser lighthouse is installed. However, the slit-shaped laser beam is a light beam CW2, one side of which is radiated in a direction perpendicular to the rotation axis and rotates clockwise, and the other side is a light beam CW1 which is radiated at an angle ψ with a light beam CW2 of that one side. One side is composed of a light beam CCW1 which is irradiated in a direction perpendicular to the rotation axis and is rotated counterclockwise, and the other side is composed of a light beam CCW1 of one side and a light beam CCW2 which is irradiated at an angle ψ. A sensor for detecting the laser beam emitted from the second laser lighthouse. Is installed, the time difference for detecting the laser beams emitted from the first laser lighthouse and rotating in mutually opposite directions is measured and input to the arithmetic device, and the measurement points are provided with the first and second laser lighthouses. The angle α formed from the reference line connecting the two reference points is calculated, and from the time difference of the light rays emitted from the second laser lighthouse, the measurement points are X, Y at the reference point where the second laser lighthouse is installed.
The angle β with respect to the plane is calculated.

In addition, according to the angle measuring device in the three-dimensional space using the laser beam according to the present invention, the angle measuring device is installed at two reference points on the X and Y planes at a predetermined interval and at a constant speed in the clockwise and counterclockwise directions. First and second laser lighthouses for irradiating a rotating laser light, and the first and second laser lighthouses installed at measurement points.
Detection sensor for detecting a laser beam from the laser lighthouse, a time measuring device for measuring a time difference between the laser beam rotating in the clockwise direction and the counterclockwise direction received by the detection sensor, and the first time measured by the time measuring device. Calculation for inputting a measurement value for one laser lighthouse to calculate an angle with respect to a reference line connecting the two reference points, and inputting a measurement value for a second laser lighthouse for calculating an angle with respect to the X and Y planes And a device for irradiating the first and second laser lighthouses with a slit-shaped laser beam, and the one side of the slit-shaped laser beam is radiated in a direction perpendicular to the rotation axis to rotate clockwise. CW2 and the ray CW1 which is irradiated at an angle ψ with the ray CW2 on the other side, and ray CCW1 which is rotated counterclockwise by radiating one side in the direction perpendicular to the rotation axis and the other side is the one. It is composed of a light CCW2 emitted by the light CCW1 and angle [psi.

[Principle of the Invention] The present invention is based on the principle of the previously proposed Japanese Patent Application No. 60-267418.
The invention described in Japanese Patent Publication No. 11806/1992 is used. Therefore, the outline of the prior invention will be described first.

As shown in FIG. 1, when the reference line AB is on the (x, y) plane and the point C, that is, the measurement point is on the same plane,
Considering how to obtain the angle θ formed by the point C and the reference line AB, when the laser beam is emitted from the point A to the point B and the laser beam is rotated at a constant speed in the counterclockwise direction CCW and the clockwise direction CW. , Point C is a counterclockwise laser beam
Observe the CCW and then the clockwise beam CW. And we will observe the CCW beam CCW again. When the measurement point C exists in the third or fourth quadrant, it is clear that the observation order is the same but the principle is the same.

Since the observation times are different in this way, the angle θ can be calculated from this observation time difference. That is, as shown in FIG. 2, since the observation time differences at the point C are t1, t2, t1 ..., The angle θ is θ = (t1−t2) / (| t1−t2 |) × t1 / (t
1 + t2) × 180 °

By the way, it is problematic to prepare a counterclockwise rotating laser and a clockwise laser both in a method of driving at a constant speed and in terms of cost. Therefore, one rotating laser is used and a mirror is used. In order to obtain the two-direction rotating lasers CCW and CW and to distinguish the counterclockwise laser CCW and the clockwise laser CW by applying A laser beam is applied.

As described above, when a laser rotating on the x, y plane, that is, a laser rotating at a constant speed in both directions around the z axis perpendicular to the x, y plane is applied, the measurement point on the x, y plane becomes a reference line. Angle, that is, the direction, is obtained. Similarly, when a laser that rotates in both directions around the x axis at a constant speed is used, the angle formed by the measurement point with the x and y planes at the reference point is obtained.

[Advantageous Effects of the Invention] According to the present invention, since the intersection point is obtained by using the two slit-shaped laser beams as described above, the sensor can easily detect the beam, and the three-dimensional angle can be easily obtained. . Therefore, for example, even if a moving object is provided with a sensor, the three-dimensional direction can be obtained. By using the slit-shaped laser beam as described above, the sensor can easily detect the beam, which is extremely suitable for angle measurement.

[Embodiment] In carrying out the present invention, a reference direction detection sensor is used to correct a reference line connecting reference points, and a laser beam detection sensor includes a photodiode, an amplification shaping circuit,
It can be configured with a threshold circuit or the like. The time difference for receiving the laser beam is constituted by a crystal oscillation circuit, a gate circuit, a counter circuit, etc., and the arithmetic unit can be constituted by a microcomputer. However, since these devices are all well known to those skilled in the art and can be arbitrarily applied, they are only shown as block diagrams in the following embodiments.

An embodiment of a laser lighthouse will be described below with reference to FIGS. 3 and 4 of the accompanying drawings.

In FIG. 3, the laser lighthouse 1 has a fixed housing 10
And a rotary table 20 provided in the housing, and various optical devices described later attached to the housing 10 and the rotary table 20.

The fixed housing 10 is formed in a substantially box shape, and the laser oscillator 30 is fixed to the center of the bottom wall 11 of the fixed housing 10. And
The laser beam X emitted from this oscillator is the central through hole 12
To reach the inside of the housing. The fixed housing 10 is integrally provided with a support member 13 at an upper portion thereof. The mirror 2 is fixed to the support member so that the reflection surface S coincides with the rotation center line C.

A stator 21 which is a component of the motor is provided inside the fixed housing 10, and a flat plate-shaped rotor 22 is rotatably supported by a bearing 23 so as to face the stator. A rotary table 24 is integrally mounted on the rotor 22. A through hole 25 is formed at the center of rotation of the rotary table, and the laser beam X from the laser oscillator 30 reaches the pentaprism 3 fixed to the rotary table 24 through the through hole 25.

As described above, the pentaprism 3 is fixed to the center of the rotary table 24, and the triangular reflecting prism 4 and the beam splitter 6 are provided at the peripheral portion, and the cylindrical concave lens 5 is provided at an intermediate position so that the axial center is obliquely upward. Are provided integrally so as to face. Therefore, when the rotary table 24 rotates, the prism 3, the cylindrical concave lens 5, the reflecting prism 4, and the splitter 6 rotate integrally.

Since the laser lighthouse 1 is configured as described above, the laser beam X emitted from the laser oscillator 30 is refracted by the pentaprism 3 as shown in the figure and reaches the cylindrical concave lens 5. In the cylindrical concave lens 5, the laser beam is diffused only in the vertical direction as shown in the figure, and a part of the light beam L1 at the first end goes straight through the beam splitter 6 to become the laser beam CCW1, and the remaining light beam Is refracted by the reflection prism 4 and reflected by the mirror 2 to become a laser beam CW1. A part of the laser beam L2 at the second end goes straight through the reflecting prism 4 and the beam splitter 6 to become a beam CCW2, and the remaining beam is refracted by the reflecting prism 4 and further reflected by the mirror 2. Then it becomes a ray CW2.

Therefore, the laser beam that has passed through the concave lens 5 and passed through the prism, the mirror, or the like or being refracted is CCW2 in a slit shape.
Between CCW1 and CCW1 and CW1 and CW2, and is irradiated obliquely upward. Therefore, if the measurement point exists in the range indicated by the angle ψ in FIG.
It will be irradiated to CW and CCW. And now turntable 20
When viewed from above and rotated counterclockwise, the laser beam
CCW1 and CCW2 rotate in the same direction as the turntable, but rays CW1 and CW
W2 is inverted because the mirror 2 is reflected, and rotates clockwise. This rotational direction relationship is schematically shown in FIG.

As described above, since the laser beam is emitted, when the measurement point exists in the measurement area shown in FIG. 3, the measurement point is emitted to the counterclockwise ray CCW and the clockwise ray CW. Therefore, as described with reference to FIGS. 1 and 2, if the time difference is measured, the angle or direction of the measurement point can be calculated. If a sensor that receives the counterclockwise light beam CCW and a sensor that receives the clockwise light beam CW are provided, the angles of the measurement points other than the measurement area can also be calculated.

Therefore, the measuring method will be described with reference to FIG. The reference point A is set on the x and y planes, and the reference point A
Then, the laser lighthouse 1 is installed so that the center of rotation C of the laser lighthouse 1 coincides with the Z axis, and the laser beam is emitted. A laser beam detection sensor 50 is provided at the measurement point C to detect the laser beam. Further, a time measuring device 51 and a computing device 52 are provided.

Now, when the laser beam is applied as described above, the sensor 50 detects the light beams CCW and CW. Then, the signal is input to the time measuring device, and the time differences t1, t2, t1, t2 ... Are measured as described with reference to FIG. Therefore, from these time differences t1 and t2, the angle α at which the measurement point C is formed by the reference line AB is α = (t1−t2) / (| t1−t2 |) × t1 / (t1
+ T2) × 180 ° is calculated by the arithmetic unit 52.

Now, according to the present invention, the position of the measurement point in the three-dimensional space can be easily measured. For example, as shown in FIG. 6, the laser lighthouse 1 is installed at reference points A and C on the x-axis so that the center of rotation coincides with the Z-axis, and the angles α and γ are measured. Since the distance l between the reference points A and C is previously obtained, the two corners and one side are determined, the coordinates (x ', y') of C'are calculated by the arithmetic unit 52, and the angle β is calculated. Therefore, Z is also calculated, and its coordinates (x ', y', z ') are calculated. These calculated values can be displayed on the display or printed out.

When the laser beam is emitted from the three reference points in this way, the laser beam detection sensor 50 needs to be configured to distinguish them. An example thereof is shown in FIG. That is, the sensor 50 is composed of a photodiode or the like, but since the installation point of the laser lighthouse is different, three sensors a ', b', and c'are provided by using this, and the respective sensors a ', b. ′ And c ′ are designed to receive only the light beams of the lighthouses provided at the respective reference points A, B, and C. Although not shown, the wavelength of the laser of the laser lighthouse may be changed so that the laser light can be separated by the optical filter, or the rotation cycle of the lighthouse can be changed so as to be discriminated by the microcomputer.

[Effects of the Invention] As described above, according to the present invention, since the laser beam is expanded in a slit shape, the measurement range is wide and therefore the angle of the measurement point existing in the three-dimensional space can be easily measured. Furthermore, since the laser beam has a slit shape, it is possible to measure a moving measurement point. Further, since the laser beam is used, there is an effect that the measurement can be performed instantly and the data can be easily displayed and recorded.

[Brief description of drawings]

1 and 2 are explanatory views showing the relationship between the light receiving time interval and the angle of the laser beam at the measurement point, FIG. 3 is a side view showing one embodiment of the laser lighthouse according to the present invention, and FIG. FIG. 5 is a schematic plan view of a laser lighthouse, FIGS. 5 and 6 are explanatory views showing different measuring methods, and FIG. 7 is a schematic perspective view showing one embodiment of a laser beam detection sensor. 1 ... Laser lighthouse, 2 ... Mirror, 20 ... Turntable, 30 ...
… Laser oscillator, 50 …… Laser beam detection sensor, 51 ……
Time measuring device, 52 ... Arithmetic device, CCW ... Laser beam rotating counterclockwise, CW ... Laser beam rotating clockwise, α ... Angle formed by reference point with reference line, β ... Measuring point Is the angle formed by the x and y planes at the reference point

Claims (2)

[Claims] 1. An X-axis and a Y-plane, which are spaced apart from each other by a predetermined distance.
A first laser lighthouse that rotatably irradiates a slit-shaped laser beam about a Z axis perpendicular to the Y plane is installed, and the other reference point is located in the X and Y planes and is orthogonal to the Z axis. A second laser lighthouse for rotating and irradiating a slit-shaped laser beam is installed around the axis similarly to the first laser lighthouse, and one side of the slit-shaped laser beam is irradiated in a direction perpendicular to the rotation axis. Rays that are rotated clockwise
CW2 and a ray CW1 which is irradiated on the other side at an angle ψ with the ray CW2 on its one side, a ray CCW1 which is rotated counterclockwise by being illuminated on a side perpendicular to the axis of rotation and a ray CCW1 on the other side CC
It is composed of W1 and a light beam CCW2 emitted at an angle ψ, and a sensor for detecting the laser beam emitted from the first and second laser lighthouses is installed at the measurement point, and is emitted from the first laser lighthouse. The time difference for detecting the laser beams rotating in mutually opposite directions is measured and input to the arithmetic device, and the angle α formed by the measurement point from the reference line connecting the two reference points where the first and second laser lighthouses are installed is defined as The laser is characterized in that the angle β with respect to the X and Y planes at the measurement point at the reference point where the second laser lighthouse is installed is calculated from the time difference between the light beams emitted from the second laser lighthouse. An angle measurement method using a light beam in a three-dimensional space. 2. First and second laser lighthouses which are installed at two reference points on the X and Y planes at predetermined intervals and irradiate laser light which rotates at a constant speed in a clockwise direction and a counterclockwise direction, Time measurement for measuring a time difference between a detection sensor installed at a measurement point and detecting laser beams from the first and second laser lighthouses, and a laser beam rotating clockwise and counterclockwise received by the detection sensor. The device and the measured value of the first laser lighthouse measured by the time measuring device are input to calculate the angle with respect to the reference line connecting the two reference points, and the measured value of the second laser lighthouse is input. And a computing device for computing an angle with respect to the X and Y planes, the first and second laser lighthouses irradiate a slit-shaped laser beam, and the slit-shaped laser beam is on one side thereof. Rays of light CW2 and the other side that is irradiated in a direction perpendicular to the rotation shaft rotates in a clockwise direction one side CW2
And a ray CW1 radiated at an angle ψ, a ray CCW1 radiated on one side in a direction perpendicular to the axis of rotation and rotated counterclockwise, and a ray CCW1 radiated at an angle ψ on the other side with a ray CCW1 on one side.
An angle measuring device in a three-dimensional space using a laser beam, which is configured by W2.