JPS6186608A - Angle detecting method of angle changing mechanism of three-dimensional configuration measuring apparatus - Google Patents

Abstract

PURPOSE:To make the direction of the coordinate-axis of a three-dimensional driving mechanism correspond to the rotary angle of an angle changing mechanism, by using lighting body for specified angle alignment, actually measuring the shape of a lighting surface, and detecting the direction of the angle of the original point of the angle changing mechanism. CONSTITUTION:In detecting the direction of the angle of the original point of an angle changing mechanism 4, the first operation is performed as follows. A lighting body 14 for angle alignment, which has a reference point on a lighting surface 15, is provided in parallel with a reference axis of a driving mechanism 7. Then, the positions of the lighting surface 15 and the rotary center of the angle changing mechanism 4, to which a distance meter 1 is attached, are determined. As the second operation, the angle changing mechanism 4 is turned, the shape of the lighting surface 15 of the lighting body 14 for angle alignment is measured and the data is processed. Thus the direction of the angle of the original point of the angle changing mechanism 4 is detected. Therefore, the direction of the coordinate axis of the three-dimensional driving mechanism is made to correspond to the rotary angle of the angle changing mechanism, which changes the lighting angle of the distance meter, and the shape of the body to be measured can be accurately measured.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an angle detection method of an angle change mechanism of a three-dimensional shape measuring device that measures the shape of an object with a non-contact distance meter using laser light or the like. In particular, the present invention relates to a method of making the irradiation angle of a rangefinder's light on an object correspond with the direction of the coordinate axes of a three-dimensional drive mechanism with high precision.

[Background of the invention]

In recent years, with the rapid progress of optoelectronics,
For measuring the three-dimensional shape of objects such as machined products, Optical Bushi/
A non-contact measurement method using a glass has been developed. Among these, we use a distance meter that uses laser light etc. as a sensor,
The mainstream method is to attach this to a three-dimensional drive mechanism and measure the shape, and an example of this is also introduced in the document entitled "Measurement of object shape using a light spot detection sensor" in the February 19B3 issue of Sensor Technology J. has been done.

In order to obtain highly accurate measurement results with this type of measurement method, it is necessary to determine the direction of the coordinate axes of the three-dimensional drive mechanism itself and the distance 1'i.
An operation that corresponds with the rotation angle of the angle changing mechanism that rotates the LF meter to change the irradiation angle with high precision (angle detection)
is necessary.

For this reason, in the past, a specific surface on the outside of the rangefinder was used as a reference surface, and this reference surface was assumed to be parallel or perpendicular to the irradiation optical axis of the rangefinder, and mechanically the coordinate axis of the three-dimensional drive mechanism itself was There was a correspondence between the direction of the angle change mechanism and the rotation angle of the angle change mechanism. However, this method has the problem of not being able to obtain high accuracy despite its complicated procedures.

Therefore, in this type of measurement method, a simple and highly accurate angle detection method has been desired.

[Purpose of the invention]

An object of the present invention is to provide an angle detection method that easily and accurately corresponds the direction of a coordinate axis of a three-dimensional drive mechanism and the rotation angle of an angle change mechanism that changes the irradiation angle of a rangefinder. be.

[Summary of the invention]

The present invention detects the origin angle direction of the angle changing mechanism by actually measuring the shape of the irradiation surface using an angle adjustment irradiation body having a reference point within the irradiation surface. be.

That is, the present invention is characterized by: a rangefinder that measures the distance to an object by emitting light; an angle changing mechanism that attaches the rangefinder and changes the angle at which the rangefinder irradiates the light to the object; Attach the angle change mechanism and set the distance meter to 3.
It is equipped with a three-dimensional drive mechanism that drives the target in a three-dimensional manner, and a data processing mechanism that calculates the coordinates of the irradiated point from the distance measurement value by the rangefinder, the irradiation angle of the rangefinder, and the drive amount information of the three-dimensional drive mechanism. In a measurement method for measuring the shape of a measurement object, an angle adjustment irradiator having a reference point on the irradiation surface is installed parallel to the reference axis of a three-dimensional drive mechanism, and then a distance meter is attached to the angle change mechanism. Place the rotation center position at a fixed position where the shape of the irradiation surface can be measured, then measure the shape of the irradiation surface with a rangefinder while rotating the angle change mechanism, and use this measurement value to determine the shape of the irradiation surface reference point. A method for detecting an angle of an angle changing mechanism of a three-dimensional shape measuring device includes determining coordinate values and using the coordinate values to detect an origin angular direction of the angle changing mechanism using a data processing mechanism.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 7. In FIG. 1, a rangefinder 1 is rotatably attached to an angle change mechanism 4 which has a rangefinder drive motor 3 built into a 7-lunge 2, and the irradiation optical axis 5 of the rangefinder 1 and the rotation of the angle change mechanism 4 are shown in FIG. The axis S is configured to have an intersection point N. The angle changing mechanism 4 is attached to the three-dimensional drive mechanism 7 via the attachment part 6 of the three-dimensional side M mechanism. Therefore, the rangefinder 1 can be moved three-dimensionally (in the x, y, and z-axis directions in the figure) by the rotation of the object to be measured 8 by the three-dimensional drive mechanism 7, and can also be moved by the angle changing mechanism. The irradiation angle can be changed depending on the shape of the measurement object 8.

FIG. 2 shows a schematic structure of the rangefinder 1, in which irradiation light such as a laser is emitted from a light source 9, and the irradiation lens 1
0 on the irradiation optical axis 5, and irradiates a point P on the surface of the object to be measured 8. Diffuse reflected light from point P is reflected by a condenser lens 1 arranged on an axis 11 forming an angle r with the irradiation optical axis 5.
The light is collected by the light receiver 2 and detected by the light receiver 13. The principle of distance measurement is that when the distance between the object to be measured 8 and the distance meter 1 changes, the position of the reflected light incident on the light receiving surface of the light receiver 13 changes, and this change is detected electrically. . However, due to constraints such as the size of the light-receiving surface, there are naturally limitations to the distance measurement barrier, and in Figure 2 p
The range is between / and P" (distance is Ll, ≦L≦L, . . . ).

When configured as described above, the coordinates (Xp, Yp, Zp) of the measurement point P on the object are three-dimensional, as shown in FIG. (
Xs, YN, ZN), the rotation angle θ of the angle change mechanism 4, and the distance measurement value by the distance meter 1 are input to a data processing mechanism (not shown), and the data processing mechanism calculates using the formula below. Therefore, it is possible to measure the shape of an object as a series of these points.

Here, θ is the angle O1 when it coincides with the Y-axis direction in the figure.
In other words, it is defined as the angular direction of the origin. Therefore, it can be seen that if the origin angle direction of the angle changing mechanism 4 does not match the Y-axis direction of the three-dimensional drive mechanism 7, the shape of the object to be measured 8 cannot be measured by the coordinate calculation of the above equation (1).

In detecting the origin angle direction of the angle change mechanism, the following two operations are performed in the present invention.

(A) An angle changing mechanism in which the angle adjustment irradiator 14 having a reference point on the irradiation surface 15 is installed parallel to the reference axis of the three-dimensional drive mechanism, and then the irradiation surface 15 and the distance meter 1 are attached. Perform positioning with the rotation center of step 4.

(B) The angle change mechanism 4 is rotated, the shape of the irradiation surface 15 of the angle adjustment irradiation body 14 is measured, data processing is performed, and the origin angle direction of the angle change mechanism 4 is detected.

Next, the above operating method (A) according to the present invention will be explained using FIG. In this embodiment, the angle adjustment irradiator 14
The cross-sectional shape of the irradiation surface 15 is a concave surface including two orthogonal sections having an intersection (reference point), and the outer shape of the irradiation body is a rectangle tA.

The procedure is performed as follows.

1. Without a housing, place the angle adjustment illuminator 14 on the movable table 16 of the three-dimensional drive mechanism so that the side surface 18 is parallel to the Y-axis of the three-dimensional drive mechanism.

Specifically, as shown in FIGS. 4 and 5, the lower part 17 of the angle adjustment irradiator 14 is cut into a three-dimensional groove in the movable table 16 of the drive mechanism, which is cut in a direction perpendicular to the Y axis. Use means such as fitting the

The side surface 18 of the angle adjustment irradiator 14 parallel to the Y axis of the 2-3-dimensional drive mechanism is brought into contact with the 72-inch portion 2 of the angle change mechanism 4. In this case, the rotation center position of the angle changing mechanism soil is assumed to be N1 (Xt, Y+).

1 The angle change mechanism 4 is located at the intersection point Pc of two straight lines on the irradiation surface 15.
Set to nN2 (X!, Y!) at a distance of Δt in the X-axis direction from a straight line PeNo passing through and parallel to the Y-axis. The Xs coordinate at this time is set by the following formula using the known value t'.

X z = X 11'...
......(2) Here, tl: distance in the X-axis direction between the plane 18 of the irradiator for angle adjustment parallel to the Y-axis and the intersection point Pc of the two straight lines, D, 7 langes 2 of the two-angle changing mechanism diameter, Δt
: It is determined by the known amount of deviation in the X-axis direction between the straight line PcNo passing through the intersection point Pc of the two straight lines and parallel to the Y-axis, and the rotation center N: of the angle changing mechanism. However, Y2 is when the irradiation surface 15 is irradiated,
It is necessary to set it at a position that does not fall outside the distance measurement range described above.

Next, FIG. 6 explains a specific method of applying the armor in the above-mentioned operation (B) according to the present invention, and the procedure is performed as follows.

1. Rotate the angle change mechanism 4 so that the rangefinder 1 is on the irradiation surface 15
The irradiation is performed at an arbitrarily set irradiation starting point P1 within the cross section. Here, X@ is defined as υ in the direction of this irradiation optical axis, and the y-axis is defined as passing through point N2 and perpendicular to the X-axis. Also,
The rotation angle θ of the angle changing mechanism 4 in this case is the rotation angle from this X axis.

2. Measure the cross-sectional shape of the irradiation surface 15 while rotating the angle changing mechanism 4. Here, the coordinates (Xt
, Y+) is calculated by the following formula, assuming that the rotation angle is 01 and the distance measurement value of the distance meter 1 is Ll.゛λ Based on the coordinates of the two straight line parts of the cross section of the irradiated surface obtained in 2 above, data processing is performed to find the equations of the two straight lines,
Coordinates of the intersection of two orthogonal lines Pc(xc.

yc).

4. As shown in Fig. 7, the value of the original rotation angle θ of the angle change mechanism 4 is determined when the irradiation light of the rangefinder is directed in the Y-axis direction (Name direction and NxPh direction), that is, when the origin angle direction is It is 0. The difference θ- between this θ and the rotation angle θ from the X axis is given by the following formula.

θd=θ, +Δθ (4) Here, θ is determined by the following equation based on the coordinates of Pc (x@+Ya).

θ, =t==-1(-) ・・・・・・
...(5)X.

On the other hand, the value of Δθ is determined as follows. Point P,, Ph
, N2, we can see that W1 min P, Nz
(= L, ), f'la PbPc (= l t
) and the angle ZNzPhP-(=90')h are known, so Δθ can be found by the following formula.

Here, Ls=i...light...(7) Here,
The following relationship exists between the original rotation angle θ of the angle changing mechanism soil and the above-mentioned rotation angle θ, using θ obtained by equation (4).

θ = θ - θ - (8) Therefore, by substituting θ in equation (8) into equation (1), <
1) It becomes possible to measure the shape of an object using the equation.

It can be seen that by performing the operations (A) and (B) above, the origin angular direction of the rotation angle θ can be automatically detected and the rotation angle can be set. In this case, the irradiation starting point P1 does not need to be at a fixed position;
Any point on one straight line of the cross section of is acceptable. Therefore, there is no need to pay special consideration to the setting of the irradiation starting point P1, making the operation easier than in the conventional example.

At that time, the shape of the irradiation surface is the intersection point (reference point) mentioned above.
Not only in the case of a concave surface including two linear portions having a shape of 2, but also in the case of a rectangular or arcuate shape, a point specific to the shape may be used as the reference point.

Furthermore, if the rotation center position of the angle changing mechanism when measuring the irradiation surface 15 is set to the No point, that is, the position in front of the intersection point Pc of the two straight lines, the deviation angle Δθ from the Y axis shown in the above equation (5) can be There is no need to take this into account, and the angle can be detected using a simpler calculation formula.

In the above-mentioned embodiment, as a specific method for positioning the rotational centers of the angle adjustment illuminator 14 and the angle changing mechanism 14 in the operation (A), the flange 2 of the angle changing mechanism is connected to the side surface 18 of the angle adjusting illuminator 14. After making contact, set the rotation center of the angle change mechanism to point N! I mentioned how to move it to
The method of positioning these two is not limited to the above embodiment, and for example, the following structure may be used.

8M shows a case where the positioning block 19 is used to position the angle adjustment irradiator 14 and the rotation center of the angle changing mechanism 4. In this case, it is assumed that the illustrated dimension 80 of the positioning block 19 is processed according to the value of the following formula.

Here, t: the distance in the X-axis direction between the intersection point Pc of the two straight lines and the point 18 parallel to the Y-axis of the illumination body for two-angle alignment, D: the diameter of the flange 2 of the two-angle changing mechanism 4, Δt: the distance between the two straight lines This is a known amount of deviation in the X-axis direction between the direct diagonal PcNo that passes through the intersection Pc and is parallel to Y@, and the rotation center of the angle changing mechanism. Note that the operation (, B) in this case may be the same as described above.

According to this embodiment, unlike the embodiment shown in FIG. 3, the angle changing mechanism 4 is changed from point N1 to N! Since there is no need to move to five points, there is an effect that positioning of both can be done more easily.

〔Effect of the invention〕

According to the present invention, the direction of the coordinate axes of the three-dimensional drive mechanism and the rotation angle of the angle changing mechanism that changes the irradiation angle of the rangefinder can be made to correspond easily and with high precision. Therefore, the shape of the fixed object can be measured with high precision.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a three-dimensional shape measuring device used in the angle detection method of the present invention, and Fig. 2 shows the distance shown in Fig. 1! 'i!
FIG. 3 is an explanatory diagram showing an embodiment of the angle detection method of the present invention, FIG. 4 is a perspective view of an embodiment of the irradiation body for angle adjustment used in the angle detection method of the present invention, and FIG. The figure is a vertical cross-sectional view of the angle adjustment vertical projector shown in FIG. 4 fixed at 1.-1 on a three-dimensionally driven sliding table; FIGS. 6 and 7 are explanatory diagrams of the angle detection method of the present invention; FIG. 8 is an explanatory diagram showing another embodiment of the angle detection method of the present invention. DESCRIPTION OF SYMBOLS 1... Distance meter, 4... Angle change mechanism, 5... Irradiation optical axis, 7... Three-dimensional drive mechanism, 8... Measured object,
9... Light source, 10... Irradiation lens, 11... Axis line forming angle γ with the irradiation optical axis, 12... Condensing lens, 13
...Receiver, 14...Angle C [Irradiator for alignment, 15
... Irradiation surface, 16... Moving table, 17... Lower part of the irradiator for angle adjustment, 18... Surface parallel to the Y axis of the irradiator for angle adjustment, 19... Position '(determined) block.

Claims (1)

[Claims] 1. A rangefinder that measures the distance to an object by emitting light, an angle change mechanism that changes the angle of light irradiation of the rangefinder to the object while attaching the rangefinder, and a rangefinder that installs the angle change mechanism. It is equipped with a three-dimensional drive mechanism that drives the three-dimensionally, and a data processing mechanism that calculates the coordinates of the irradiated point from the distance measurement value by the rangefinder, the irradiation angle of the rangefinder, and the drive amount information of the three-dimensional drive mechanism. In a measurement method for measuring the shape of an object to be measured, an angle adjustment irradiator having a reference point on the irradiation surface is installed parallel to the reference axis of the three-dimensional drive mechanism, and then the angle at which the rangefinder is attached is adjusted. Place the rotation center position of the changing mechanism at a fixed position where the shape of the irradiation surface can be measured, then measure the shape of the irradiation surface with a rangefinder while rotating the angle change mechanism, and use this measurement value to determine the irradiation surface reference. A method for detecting an angle of an angle changing mechanism in a three-dimensional shape measuring device, characterized in that the coordinate values of a point are determined, and the origin angular direction of the angle changing mechanism is detected by a data processing mechanism using the coordinate values.