JP3705863B2 - Height measuring device and height measuring method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to the field of leveling, and more particularly to a measurement point height measuring apparatus and a measurement point height measuring method for measuring the height of a measurement point using plane light.
[0002]
[Prior art]
Conventionally, in order to measure the height of a measurement point, a laser planar 102 and a light receiving device 103 as shown in FIG. 5 have been used. The laser planar 102 emits a parallel light beam 111 having a predetermined diameter so as to intersect perpendicularly with a vertical line 112 passing through the reference point 101, and rotates around the vertical axis 112 to set a level surface. The parallel light beam 111 is received by a plurality of light receiving elements 115 of a light receiving device 103 arranged on a measurement point 113, and the light receiving element 115 is positioned on a vertical line passing through the measurement point 113. If the light receiving point 116 irradiated with the parallel light beam 111 is detected and the height from the measurement point 113 is obtained, the value and the height of the parallel light beam 111 from the reference point 101 are determined. Sato can be used for leveling.
[0003]
However, in leveling with such a laser planar, the range of height that can be measured is limited to the range in which the light receiving elements are arranged on the light receiving device. In a general light receiving device, the light receiving elements are arranged only within a few centimeters at most, and the range in which the parallel light flux can be detected is very narrow. Me other, the reference point the height difference is large and the measurement point, when parallel light beams by placing the direct light receiving device on the measuring point is that not irradiated to the light receiving element, with a special fine movement device Although a frame was used and a laser planar and light receiving device were placed on it, it was still not easy to irradiate the light receiving element with a parallel light beam.
[0004]
In this case, if a large number of light receiving elements such as photodiodes are arranged in the light receiving device or a long linear sensor is attached, the range in which the parallel light flux can be detected is increased, but it is inevitable that the cost is increased (for example, (See Japanese Utility Model Publication No. 2-133608).
[0005]
In order to eliminate such an inconvenience, it is conceivable to perform height measurement using a three-dimensional coordinate measurement system. FIG. 6 shows an example of a three-dimensional coordinate measurement system. In this system 201, an emission device 202 that emits two intersecting plane lights 207 ₁ and 207 ₂ while rotating around a rotation axis 208 is arranged at a reference point 210, and the tip of the reflection device 204 is placed on a measurement point 203. Then, the two planar lights 207 ₁ and 207 ₂ are reflected by the reflecting prisms 209 ₁ , 209 ₂ , and 209 ₃ disposed in the reflecting device 204 and received by a light detection means (not shown) included in the emitting device 202. If the signal received by the light detection means is analyzed by a computer, the value of the three-dimensional coordinates of the measurement point 203 can be calculated, so that the height of the measurement point 203 can also be obtained (for example, Japanese Patent Application No. Hei. (See 5-308035).
[0006]
However, in such a system, an optical component such as a reflecting prism is indispensable, so that the light receiving device has to be increased in size and is inconvenient to handle.
[0007]
[Problems to be solved by the invention]
The present invention has been made in order to solve the problems found in the prior art as described above. The purpose of the present invention is to provide a measuring system with a simple system configuration, a wide measuring range, and an extremely simple operation. It is to provide a height measuring apparatus and a height measuring method.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, an invention apparatus according to claim 1 includes a planar light emitting device, a light receiving device, and a computing device, and includes a height of a reference point where the planar light emitting device is arranged and a measurement point. A height measuring device for obtaining a difference in height, wherein the planar light emitting device intersects two planar lights intersecting at a predetermined angle perpendicularly with a perpendicular line passing through a reference point. Light emitting means for emitting the light and rotating means for rotating the two plane lights at a predetermined speed with the perpendicular as a rotation axis, and the light receiving device has two light detecting means fixed at predetermined positions. When the light receiving device is arranged such that a straight line connecting the light detecting means is a vertical line passing through the measurement point, the arithmetic unit is configured to receive a light receiving time at which each of the light detecting means has received the two plane lights. , The height from the measurement point of each light detection means, and the intersection line From the height of the semi-point, characterized by calculating the difference in height between the measuring point and the reference point,
The invention apparatus according to claim 2 is the height measuring apparatus according to claim 1, wherein each of the light detection means includes two light receiving elements arranged in close contact with the straight line in a vertical direction,
According to a third aspect of the present invention, there is provided a height measurement method, wherein two plane lights intersecting at a predetermined angle are emitted such that an intersection line of the two plane lights intersects a vertical line passing through a reference point perpendicularly. Then, the two plane lights are rotated at a constant speed with the vertical line as a rotation axis, and the two plane lights are received by a plurality of light receiving points arranged at predetermined positions on the vertical line passing through the measurement points. A time is detected, and a difference between a height of the measurement point and the reference point is obtained from the height of the intersection line of the two plane lights from the reference point, the light reception time, and the predetermined position. .
[0009]
The measurement principle of the present invention will be described with reference to the drawings.
[0010]
Referring to FIG. 3, A ₁ and A ₂ are two plane lights that intersect at a predetermined angle, and intersect at one intersection line. The intersecting line of the _two plane lights A ₁ and A ₂ intersects with a perpendicular passing through a reference point (not shown), and the two plane lights A ₁ and A ₂ are constant in the right direction of the drawing. It is assumed that it is rotating at an angular velocity ω.
[0011]
The two light receiving points P _A and P _B are located on a vertical line J passing through the measurement point P _0, and the light reception point P _B is fixed at a position of height b from the measurement point P _0. P _A is fixed at a position of height d from the light receiving point P _B.
[0012]
When the two plane lights A ₁ and A ₂ are rotated, the light receiving point P _A intersects the plane lights A ₁ and A ₂ at points S ₁ and S ₄ , respectively, and the light receiving point P _B is a point S ₂ respectively. , it is assumed that intersect at S _3. At this time, the points S ₁ , S ₂ , S ₃ , S _{4 form} one vertical plane. A point where the vertical plane and the intersecting line of the _two plane lights A ₁ and A ₂ intersect is defined as a point S ₀ .
[0013]
When the two plane lights A ₁ and A ₂ rotate and intersect the vertical line J, they intersect with the light receiving point P _A twice with a time interval t _A and with a light receiving point P _B with a time interval t _B. Intersect twice. In this case, if the distance between the reference point and the measurement point is L,
S ₁ S ₄ = L ・ ω ・ t _A (1)
S ₃ S ₂ = L ・ ω ・ t _B (2)
Is established.
[0014]
Here, focusing on the triangle S ₁ S ₀ S ₄ and the triangle S ₃ S ₀ S ₂ , since both triangles are similar, the ratio of the side S ₁ S ₄ to the side S ₃ S ₂ is the side S _It is equal to the ratio of the height when ₁ S ₄ and side S ₃ S ₂ are the bottom side. Therefore, according to the above equations (1) and (2),
S ₃ S ₂ / S ₁ S ₄ = t _B / t _A = a / (da) (3)
Is established.
[0015]
By the way, if the height of the reference point is h ₀ and the height from the reference point of the intersection of the two plane lights is h ₁ , the height H of the measurement point P ₀ is
H = h ₀ + h ₁ -a-b (4)
Therefore, if a is deleted using equation (3) in equation (4),
H = h ₀ + h ₁ −d · t _B / (t _A + t _B ) −b (5)
Is obtained. The height h ₁ of the line of intersection of the reference point can be measured by a tape measure or the like, the light receiving point P _A, the position b of P _B, since d is a value determined in advance, after all, the time interval t _A , T _B is measured, the height H of the measurement point can be obtained.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a height measuring apparatus according to an embodiment of the apparatus of the present invention.
[0017]
The height measuring device 2 includes a planar light emitting device 10, a light receiving device 20, and a signal processing device 23. The planar light emitting device 10 is disposed on a reference point 3, and the light receiving device 20 is Arranged on the measurement point 4, the signal processing device 23 is attached to the light receiving device 20.
[0018]
On the rotating plate 13 in the planar light emitting device 10, light emitting means having optical systems 4a and 4b shown in FIG. 2 are provided. The optical systems 4a and 4b are respectively light emitting elements 6a and 6b, and Collimator lenses 7a and 7b and cylindrical lenses 8a and 8b are provided. The light-emitting elements 6a and 6b emit intensity-modulated light, and the light is collimated by the collimator lenses 7a and 7b, respectively, and further by the cylindrical lenses 8a and 8b at appropriate angles. It is configured to be emitted from the planar light emitting device 10 into two planar lights 12a and 12b spreading in a fan shape within a certain plane.
[0019]
At this time, the optical axes 11a and 11b of the collimator lenses 7a and 7b are located in a plane perpendicular to the rotation axis 5 of the rotating plate 13 and are arranged in parallel to each other, and the light The distance between the shaft 11a and the rotation axis 5 and the distance between the optical axis 11b and the rotation axis 5 are arranged to be equal. Further, the central axes of the cylindrical surfaces of the cylindrical lenses 8a and 8b are arranged so as to intersect with the optical axes 11a and 11b at right angles, respectively, and are opposite to each other with respect to a plane perpendicular to the rotation axis 5 It is tilted at an angle of 45 °.
[0020]
Therefore, when the rotation axis 5 is leveled so as to be a vertical line passing through the reference point 3, the two plane lights 12a and 12b are inclined 45 ° in opposite directions with respect to the level surface. In this case, the planar light 12a and the planar light 12b intersect each other at a right angle, and an intersecting line 16 formed by the intersection of the both planar lights intersects the rotation axis 5 at a right angle.
[0021]
Note that the planar light 12a and the planar light 12b do not necessarily intersect at right angles, but it is preferable that the planar light 12a and the planar light 12b are greatly spread in order to increase the measurement resolution.
[0022]
The planar lights 12a and 12b have a fan shape, and the divergence angle is determined according to the distance between the reference point and the measurement point and the height to be measured. For example, when it is desired to measure to a height of 500 mm at a distance of 3 m, the divergence angle may be about 27 °.
[0023]
The planar light emitting device 10 is provided with a rotating means having a motor, and is configured such that the rotating plate 13 can rotate around the rotation axis 5 at a constant speed by the rotating means. .
[0024]
On the measurement point 4, a columnar light receiving device 20 having light detection means 21 and 22 fixed at intervals d is placed on both ends, and an axis line 24 passing through the light receiving surface of the light detection means 21 and 22 is the measurement point. 4 and is leveled by a bubble tube (not shown) so as to be vertical, the two plane lights 12a and 12b are moved at a constant speed around the rotation axis 5 by the activation of the rotating means. When the rotation starts, the two plane lights 12a and 12b are applied to the light receiving surfaces of the light detecting means 21 and 22.
[0025]
Since the measurement limit of the light receiving device 20 is half of the size of the distance d, the distance d needs to be 1 m or more in order to measure in the range of 500 mm, for example.
[0026]
The light detection means 21 and 22 have two light receiving elements, respectively, and the two light receiving elements are arranged in close contact with each other in the traveling direction of the planar lights 12a and 12b.
[0027]
The two light receiving elements will be described. Referring to FIG. 4, reference numerals 21a and 21b denote two light receiving elements included in the light detecting means 21, and the lower direction in the drawing, which is the traveling direction of the two planar lights 12a and 12b. , Are in close contact.
[0028]
Since the signal output from the light receiving element 21a is input to the inverting input terminal of the amplifier 31, and the signal output from the light receiving element 21b is input to the non-inverting input terminal of the amplifier 31, the light receiving element 21a and the light receiving element The amplifier 31 outputs a pulse signal to the pulse circuit 32 when the amount of planar light incident on 21b becomes substantially equal.
[0029]
The pulse signal is input to the arithmetic device 33, and the clock signal is also input from the clock circuit 34 to the arithmetic device 33, so that the arithmetic device 33 can detect the time when the pulse signal is input, The data is stored in the storage device 35.
[0030]
Therefore, the storage device 35 stores the time when the plane light is irradiated to the center of the light receiving element 21a and the light receiving element 21b, so that the irradiation time can be accurately stored.
[0031]
The two light receiving elements of the light detection means 22 are also connected to the arithmetic unit 33 in the same block diagram as shown in FIG. 4, and the two planar lights 12a and 12b are connected to the light detection means 21 and 22, respectively. If this is performed each time the light is irradiated, the time intervals t _A and t _B when the light detection means 21 and 22 are irradiated with the plane light can be calculated.
[0032]
The storage device 35 stores a reference point height h ₀ , a distance d between the light detection means 21 and 22, and a height b from the bottom surface of the light detection means 22. If the height h _{0 of} 3 and the height h ₁ of the intersection 16 of the reference point and the plane lights 12a and 12b are input and the time intervals t _A and t _B are calculated, the height of the measurement point 4 is calculated. H is the formula (5),
_{H = h 0 + h 1 -d} · t B / (t A + t B) - b
Can be obtained from
[0033]
The arithmetic device 33 and the storage device 35 are disposed in a signal processing device 23 attached to the center of the light receiving device 20, and the height H of the measurement point is provided in the signal processing device 23. The signal processing device 23 is configured to be displayed by a display device, and a mark 14 is engraved on the signal processing device 23 at a central position where the light detection means 21 and 22 are arranged.
[0034]
Although the embodiment in which two light detection means are arranged has been described above, three or more light detection means may be arranged on the same straight line so as to reduce the measurement error.
[0035]
【The invention's effect】
The range of height that can be measured can be made wider than before, and the efficiency of measurement work can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of the device of the present invention. FIG. 2 is a diagram showing an example of the arrangement of the optical system of the planar light emitting device of the present invention. FIG. 4 is a block diagram showing an example of the measurement circuit of the present invention. FIG. 5 is a conventional height measuring device using a laser planar. FIG. 6 is a conventional coordinate measuring device using plane light and reflected light. [Explanation of symbols]
3 Reference point 4 Measurement point 5 Rotating axis 6a, 6b Light emitting means 10 Plane light emitting device 16 Intersection line 12a, 12b Plane light 20 Light receiving device 21, 22 Light detecting means 21a, 21b Light receiving element 33 Arithmetic unit

Claims (3)

A height measuring device that includes a planar light emitting device, a light receiving device, and an arithmetic device, and obtains a difference between a height of a reference point on which the planar light emitting device is arranged and a height of a measurement point,
The planar light emitting device is
Light emitting means for emitting two plane lights intersecting at a predetermined angle so that an intersection line of the two plane lights intersects perpendicularly with a perpendicular passing through a reference point;
Rotating means for rotating the two plane lights at a predetermined speed with the perpendicular as a rotation axis;
The light receiving device has two light detection means fixed at predetermined positions,
The arithmetic unit is:
When the light receiving device is arranged so that a straight line connecting the light detecting means is a vertical line passing through the measurement point, the light receiving times when the light detecting means receive the two plane lights, and the light detecting means A height measuring apparatus that calculates a difference in height between the reference point and the measurement point from a height from the measurement point and a height of the reference point of the intersection line. 2. The height measuring apparatus according to claim 1, wherein each of the light detection means includes two light receiving elements arranged in close contact with the straight line in a vertical direction. Two plane lights that intersect at a predetermined angle are emitted so that the line of intersection of the two plane lights intersects perpendicularly with a vertical line passing through a reference point,
The two plane lights are rotated at a constant speed with the vertical line as a rotation axis,
Receiving the two plane lights at a plurality of light receiving points arranged at predetermined positions on a vertical line passing through the measurement point, and detecting a light reception time;
A height measurement method, wherein a difference between a height of a measurement point and a reference point is obtained from a height of the intersection line of the two plane lights from the reference point, the light reception time, and the predetermined position.

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