JPH0419490B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention provides an angle detection method and apparatus using a laser beam. More specifically, the present invention relates to a method and apparatus for measuring the angle necessary to determine the coordinates of a measurement point using a device that emits two laser beams in a rotating manner, that is, a laser lighthouse.

[Prior Art] The conventional method of determining an angle or plane position by triangulation is usually carried out using a transit, which requires at least one surveyor operating the transit and a worker holding a pole. Since two people are required, the labor cost increases and the work time is also long.

Therefore, in Japanese Patent Application No. 60-267481, the applicant proposed two
We proposed an angle measurement method and device using a laser lighthouse that irradiates a book with a laser beam.

To explain this with reference to FIGS. 7 and 8, A and B are reference points, C is a measurement point, and reference point A is the ( A symmetry axis detection sensor 2A is installed at the reference point B to detect the direction of the symmetry axis of the laser lighthouse 1B and the other laser lighthouse 1A. Also, at the measurement point C, a measurement point sensor 3 for detecting the laser beams from the laser lighthouse 1A and the laser lighthouse 1B is installed, and furthermore, at the measurement point C, a time measurement device (light reception interval measurement circuit) 4 and a coordinate calculation display device are installed. (microcomputer)
5 is provided. l is the distance between reference point A and reference point B, and is measured in advance. still,
The straight line connecting reference points A and B becomes the reference line.

Laser lighthouses 1A and 1B produce two laser beams Lccw and Lcw that rotate counterclockwise and clockwise, respectively, and are always symmetrical with respect to the reference line AB.
Rotate and irradiate. Next, sensor 3 detects the laser beam
Measure the time interval at which Lccw and Lcw are received, and use the measured values to calculate the angle θ that straight line CA connecting measurement point C and reference point A forms with reference line AB, and the angle θ formed by measurement point C and reference line AB. The angle ψ formed by the straight line CB connecting to the reference point B with respect to the reference line AB is calculated. Then, using the angles θ, ψ and the distance l, the coordinates of the measurement point C are determined by trigonometry. Therefore, with this device, measurements can be carried out quickly without requiring special skill, and data can be automatically recorded and input into a computer without using a wireless communication system. There is no risk of malfunction occurring. However, as is clear from Figure 7, with this extraction technique, the angles θ and ψ are -90°≦θ, ψ≦90° (positive in the counterclockwise direction and negative in the clockwise direction with respect to the reference line AB). Measurements can only be made within the range (180°) (same below). Therefore, in order to determine the coordinates of a measurement point outside the measurable range, the laser lighthouse 1A,
1B must be moved and positioning performed again. The work was becoming complicated. Therefore, the angle (θ,
There was a request to measure ψ) over a 360° range using a laser lighthouse.

[Object of the Invention] The present invention was proposed in response to the above-mentioned requirements, and is capable of measuring the angle necessary to determine the coordinates of a measurement point over a range of 360° using a laser lighthouse. METHODS AND APPARATUS.

[Structure of the Invention] According to the method of the present invention, an angle measurement method using a laser beam that measures the angle necessary to determine the coordinates of a measurement point using a laser lighthouse that rotates and irradiates two laser beams. , a rotating part that rotates and irradiates two laser beams in the same rotation direction at different rotational speeds to a reference point, and a fixed part that irradiates one of the laser beams to the rotating part on the reference line. and a means for receiving and detecting the laser beam and a means for measuring the reception time of the laser beam are provided at the measurement point, and the detection means measures the time interval at which the two laser beams are received; The measured values are input to a calculation device to calculate the angle that a straight line connecting the reference point and the measurement point forms with the reference line.

Further, according to the device of the present invention, in an angle measuring device using a laser beam that measures an angle necessary to determine the coordinates of a measurement point using a laser lighthouse that irradiates two laser beams in a rotating manner, the reference point A rotating part that rotates and irradiates two laser beams at different rotational speeds, and a fixed part that irradiates one of the laser beams to the rotating part, and receives the two laser beams at a measurement point. a sensor that measures the time interval at which the sensor receives the two laser beams, and a time measurement device that measures the time interval at which the sensor receives the two laser beams; and an angle calculation display device that calculates from the measured value of and displays the value.

Note that the reference line is the direction in which the two laser beams coincide.

[Operations and Effects of the Invention] Two laser beams are rotated and irradiated in the same rotation direction at different rotation speeds, and the time interval during which the two laser beams are respectively received by the detection means is determined by a predetermined relational expression. By substituting the values, the angle required to determine the coordinates of the measurement point can be calculated. For example, when the rotation speed of one laser beam is twice the rotation speed of the other laser beam, the time interval from when the detection means receives the preceding laser beam until it receives the following laser beam is t1. , if t2 is the time interval from the reception of the subsequent laser beam until the reception of the preceding laser beam again, then the angle θ (see Fig. 7)
is expressed by the following formula: θ=±2t1/t1+t2×360°...(1) (However, + is between 0 and π, and - is between π and 2π.) As is clear from equation (1), θ can be measured in the range of 0° to 360°.

That is, according to the present invention, the angle necessary to determine the coordinates of the measurement point can be found no matter where the measurement point is located on the plane. Therefore, there is no need to reinstall the laser lighthouse when surveying a new measurement point, and the labor required for measurement work is reduced.

Furthermore, the number of component parts of the apparatus of the present invention is not much different from that of the prior art (Japanese Patent Application No. 60-267481), and the overall size of the apparatus has been reduced. Note that the direction of the reference line is determined by the direction in which the fixed part of the laser lighthouse is installed, but when installing it, for example, attach a collimator to the fixed part and aim at the other lighthouse, that is, the reference point when installing the lighthouse. Alternatively, a lighthouse may be installed appropriately and a sensor may be installed at a point where the angle is known to read the preset angle.

[Preferred Embodiment] In practicing the present invention, it is preferable that the rotation speed of one laser beam is twice the rotation speed of the other laser beam. However, the ratio of the rotation speeds of the two laser beams is not limited to 2:1, and it is sufficient that a certain proportional relationship always holds. In such a case, in the above formula (1), the t1 of the molecule
The coefficient of becomes a value other than 2.

Also, the ratio of the rotation speeds of the two laser beams is 2:
1, the laser lighthouse used in the present invention has a fixed part and a rotating part, and the fixed part has a laser oscillator located on an extension of the rotation axis of the rotating part, and Equipped with a beam splitter that splits the laser beam into a straight-travelling beam and a beam reflected at right angles, and two reflecting mirrors that reflect the beam reflected at right angles twice and direct it to the center of the rotating part. , and the rotating portion preferably includes a plane mirror that reflects the light beam directed toward the center, and a reflecting mirror that reflects the straight-progressing light beam at right angles to the normal direction of the plane mirror. A light beam directed toward the center of the rotating part passes on the reference line, enters the plane mirror, and is reflected. Therefore, the angle formed by the normal line of the plane mirror and the reference line (incident angle) is 1/2 of the angle (incident angle + reflection angle) formed by the ray reflected by the plane mirror and the reference line. becomes. That is, the rotation speed (angular velocity of rotation) of the laser beam reflected in the normal direction of the plane mirror by the reflecting mirror of the rotating part is 1/2 of the rotation speed of the laser beam reflected by the plane mirror. It is.

[Examples] Examples of the present invention will be described below with reference to the drawings. (In this example, the ratio of the rotational speeds of the two beams irradiated from the laser lighthouse is 2:1.
It's getting old. ) Figures 1 to 3 show a laser lighthouse 1 used in the present invention.
Indicates 0. The laser lighthouse 10 is composed of a fixed part 12 and a rotating part 14. Here, 16 indicates the rotation axis of the rotating portion 14. The fixed part 12 is a laser oscillator 1 located on an extension of the rotation axis 16.
It has 8. Directly below this laser oscillator 18, a beam splitter 20 is provided, a first reflecting mirror 22 is provided in the direction of the beam splitter 20, and a second reflecting mirror 24 is provided directly below the reflecting mirror 22. It is provided. On the other hand, a third reflection mirror 26 is arranged in the rotating portion 14, and a plane mirror 2 is placed below the reflection mirror 26.
8 is provided. The plane mirror 28 is the rotation axis 1
6 extends in the same plane as the reflective surface, and the reflective surface is 2
They are located so that they are evenly divided. In a state before the laser lighthouse 10 turns, that is, in a state where the turning angle is 0°, the normal N of the plane mirror 28 coincides with the reference line. In the figure, reference numeral 30 denotes the base of the rotating portion 14, and the inside thereof includes means (not shown) for rotationally driving the rotating portion 14.

Laser beam L1 generated by laser oscillator 18
is the light ray L that travels straight through the beam splitter 20
2 and a ray L3 reflected at right angles.
The laser beam L2 traveling straight is reflected at a right angle by the reflecting mirror 26 and is irradiated to the outside of the laser lighthouse 10 as a laser beam LA. Here, the laser beam
The LA irradiation direction is always the normal N of the plane mirror 28.
coincides with the direction of On the other hand, the beam splitter 20
The laser beam L3 reflected at a right angle by the reflection mirror 22 is reflected at a right angle downward in FIG. The light beam becomes incident on the plane mirror 28 as a light beam L5. After being reflected by the plane mirror 28, it is irradiated to the outside of the laser lighthouse 10 as a laser beam LB. As described above, the irradiation direction of the laser beam LA always coincides with the direction of the normal N to the plane mirror 28. That is, in FIG. 3, the rotation angle θ of the laser beam LA is equal to the rotation angle of the rotating portion 14 (FIG. 1). On the other hand, the laser beam L5 reflected by the reflection mirror 24 in the fixed portion 12 always travels on the reference line and enters the plane mirror 28. and,
The angle of incidence of the external laser beam L5 on the plane mirror 28 is equal to the angle θ between the reference line and the normal N.
Therefore, the laser beam reflected from the plane mirror 28
The angle between LB and the reference line (the turning angle of the light beam LB) is the sum of the above-mentioned incident angle and reflection angle, that is, 2θ.
That is, the ratio of the turning angles of the laser beams LA and LB is 1:2.
Therefore, the ratio of the turning angle to the angular velocity (turning speed) is also 1:
It becomes 2.

Next, angle measurement according to the present invention will be explained.

The measurements of the present invention shown in FIG. 4 are similar to the prior art measurements shown in FIGS. 7 and 8. That is, in FIG. 4, the aforementioned laser lighthouse 1 is located at the reference points A and B.
One unit 0A and one unit 10B are arranged, and C in the figure
is the measurement point whose coordinates should be determined. At measurement point C, there is a sensor 3 that receives laser beams LA and LB.
2. Time measurement device 3 that measures the interval of light reception time
4. An angle calculation display device 36 is installed which calculates and displays the required angle θ or ψ from the measured time interval. As the angle calculation display device 36, for example, a microcomputer can be used.

Further, the laser lighthouses 10A and 10B are provided with reference line matching sensors 38A and 38B for completely matching the reference lines of the respective laser lighthouses.

The sensors 38A and 38B are composed of, for example, photodiodes, and as shown in FIG. 2, before the laser lighthouse turns, the sensors 38A and 38B align the reference lines by receiving the other laser beam LA or LB, respectively. will be carried out.

As explained in the related art, once the length L and the angles θ and ψ of the reference line connecting the reference points A and B are determined, the coordinates of the measurement point C are determined.
Here, since the length L can be easily measured, in the end C
To find the coordinates of , just find the angles θ and ψ.

Since the manner in which the angles θ and ψ are determined is almost the same, only the method of measuring the angle θ using the laser lighthouse 10A on the left side of FIG. 4 will be described. However, the laser beams LA and LB are assumed to rotate counterclockwise in FIG. 4.

FIG. 5 shows the time interval at which the sensor 32 receives the laser beams LA and LB at the measurement point C. Measurement point C located at a position forming angle θ
The sensor 32 first receives the preceding laser beam LB, and then receives the following laser beam LA. The time interval during this time is indicated by t1 in FIG. The time interval from when the sensor 32 receives the laser beam LA until it receives the laser beam LB again is indicated by t2 in FIG. Here, since the angle θ is expressed by the above-mentioned equation (1), ie, θ=2t1/t1+t2×360°, θ can be calculated by substituting the values of t1 and t2 measured by the time measuring device 34. t
The angle calculation and display device performs substitution of the values of 1 and t2 and calculation of θ.

In FIG. 5, part of the graph showing the laser beam LB is a dotted line, but during the period corresponding to this portion, the laser beam L5 (FIG. 1) only irradiates the back side of the plane mirror 28 and is not reflected. do not. Therefore, the laser beam LB is not irradiated.

In FIG. 6, a sensor 32, a time measuring device 3
4. The details of the configuration and functions of the angle calculation display device 36 are shown in a block diagram. In FIG. 6, a subscript A is attached to a device that functions by the laser beam from the laser lighthouse 10A, and a subscript B is attached to a device that functions by the laser beam from the laser lighthouse 10B. In order to eliminate malfunctions in receiving the laser beam, the sensor 32A for receiving the laser beam from the laser lighthouse 10A and the sensor 32B for the laser lighthouse 10B are arranged with a slight distance in the height direction. When the sensors 32A, 32B receive the laser beam, they generate electrical signals, and the electrical signals are amplified and shaped into waveforms by amplifying and shaping circuits 33A, 33B, and are input to time measuring devices 34A, 34B. The time measurement devices 34A and 34B determine t1 and t2 (FIG. 5) based on the amplified signals, and output the values to the angle calculation display device 36. The angle calculating function 51A of the device 36 calculates the angle θ by substituting the values of t1 and t2 outputted from the time measuring device 34A into the above-mentioned equation (1). On the other hand, the angle calculation function 51B calculates the angle ψ using the values of t1 and t2 output from the time measuring device 34B. The coordinates of the measurement point C are calculated by the coordinate calculation function 53 from the calculated angles θ and ψ and the value of L (FIG. 4) input by the reference line length input function 52, and the coordinates are calculated by the display function 54. is displayed.

[Summary] As explained above, according to the present invention, the angle required to specify the coordinates of a measurement point is measured using a laser lighthouse that emits two laser beams that rotate at different speeds. There is. According to the present invention, there are the following advantages.

a. It is possible to measure 360 degrees around the laser lighthouse. b. Surveying can be done by one person. c. Can be measured at any position on a plane. d. The positions of several points can be measured at the same time. e.It can be measured instantly.
f. It is also possible to measure while moving. g. It is easy to handle and does not require skill. h. Can be measured with considerable accuracy. i. The device is small, weighs, and can be provided at low cost. j. Data can be automatically recorded and input into a computer. k. The entire measuring device can be made smaller.

Furthermore, the present invention can be used not only for ordinary surveying but also for position measurement and control of mobile robots and the like.

[Brief explanation of drawings]

FIG. 1 is a side view showing the structure of a laser lighthouse used in the present invention, FIGS. 2 and 3 are diagrams explaining the relationship between the turning angles of two laser beams irradiated from the laser lighthouse, and FIG. 5 is a diagram illustrating the arrangement of the measuring device of the present invention, FIG. 5 is a diagram showing the relationship between the turning angle of the two laser beams and the detection timing, and FIG.
The figure is a block diagram showing the functions of each device at the measurement point, and FIGS. 7 and 8 are diagrams explaining the prior art. 1A, 1B, 10, 10A, 10B... Laser lighthouse, 3, 32, 32A, 32B... Sensor,
4, 34, 34A, 34B... time measuring device,
5, 36... Angle calculation display device, A, B... Reference point, C... Measurement point, LA... Leading laser beam, LB... Following laser beam.

Claims (1)

[Claims] 1. In an angle measurement method using a laser beam, in which the angle required to determine the coordinates of a measurement point is measured using a laser lighthouse that rotates and irradiates two laser beams, A rotating part that irradiates two laser beams in the same rotating direction at a rotating speed of 300 degrees, and a fixed part that irradiates one of the laser beams to the rotating part on a reference line. A means for receiving and detecting the laser beam and a means for measuring the reception time of the laser beam are provided, the detecting means measures the time interval at which the two laser beams are received, and this measured value is sent to a calculation device. An angle measuring method using a laser beam, which comprises inputting information and calculating the angle formed by a straight line connecting a reference point and a measurement point with respect to the reference line. 2. In an angle measuring device using a laser beam that measures the angle necessary to determine the coordinates of a measurement point using a laser lighthouse that rotates and irradiates two laser beams, two angles are measured at different rotation speeds at a reference point.
It is equipped with a rotating part that rotates and irradiates the laser beam of the book, and a fixed part that irradiates one of the laser beams to the rotating part, and at the measurement point, the two
A sensor that receives the laser beam from the book, a time measuring device that measures the time interval at which the sensor receives the two laser beams, and a straight line connecting the reference point and the measurement point is formed with respect to the reference line. An angle measuring device using a laser beam, comprising: an angle calculation display device that calculates an angle from the measured value at the time interval and displays the calculated value.