JPH0338523B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a non-contact method for automatically measuring three-dimensional coordinates using an optical displacement meter.

[Prior art]

Conventionally, this type of measurement has been carried out by the method shown in FIG. In the figure, 1 is an orthogonal three-axis movement mechanism of X, Y, and Z in which a linear scale is inserted, and 2
is a three-dimensional contact sensor attached to its Z axis, 3
is a ball probe that touches the measurement surface in the sensor, 4 is the free-form surface to be measured, and 5 is a line laid on the free-form surface 4.

Next, the operation will be explained. A line 5 on the measurement surface 4 on which the probe part 3 of the contact sensor is to be measured
The probe also touches this line, and at this moment the probe generates a signal as it makes contact. Using this signal, sample the coordinate data of the linear scale installed on three orthogonal axes. In this way, when measuring coordinates on a line, the tip of the probe is manually brought into contact with the line.

The conventional contact-type three-dimensional coordinate measurement method is performed as described above, so a person manually holds the probe part on a line on the object to be measured.
It took a lot of time and effort, and the more complex the curved surface the target lines were drawn, the more difficult the task became.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional ones as described above. Instead of a contact probe, an optical displacement meter that outputs a light amount control amount is used to measure the measurement surface and the linear shape on it. The purpose of the present invention is to provide a device that automatically measures three-dimensional coordinates on a line while weaving the line by sensing the difference in light intensity between the line and the line.

[Embodiment of the Invention] An embodiment of the invention will be described below with reference to the drawings. Figure 2 is a block diagram of this system, where 1 is an orthogonal three-axis movement mechanism with a linear scale inserted, 6
is a non-contact optical displacement meter that outputs the light amount control amount,
7 is a rotating shaft mechanism that controls the angles θ, β, and γ axes of the optical displacement meter 6 and its angle indexing mechanism; 8 is the coordinate value of the linear scale of the three-axis moving mechanism 1, the value of the optical displacement meter 6, and the mechanism A coordinate calculation processor 9 calculates the coordinates of the spot point created by the laser beam emitted from the optical displacement meter 6 on the surface of the object to be measured from the angle detection value 7; a supervising processor for supervising; 10 a reverse coordinate transformation calculation processor that calculates the next moving coordinate value from the current coordinate value and converts it into a linear scale value or angle;
Reference numeral 11 denotes a servo amplifier that operates the linear scale moving mechanism 1 and rotating shaft mechanism 7.

Next, the operation will be explained. As shown in FIG. 3a, there is a line 5 made of a material different from the surface on the measurement surface 4, and when the optical displacement meter 6 moves in the direction of the arrow and crosses this line, the optical displacement Since the reflected light from the spot points 13 created by the six laser beams 12 on the measurement surface differs depending on the material, the light amount control amount C ₀ and the displacement amount output from the optical displacement meter 6 are as shown in Figure 3b. . The amount of displacement is constant because the distance between the measurement surface and the optical displacement meter is the same, whereas the amount of light amount control changes on the line. Therefore, by examining this light amount control amount, it is possible to sense where the line exists on the measurement surface.

FIG. 4 shows the movement of the laser spot point 13 when measuring the coordinates of a line 5 drawn on the measurement surface 4 made of a material different from that of the measurement surface. When the line 5 crosses the laser spot, the light quantity control amount output from the optical displacement meter changes, so by grasping this signal change, the moving angle of the laser spot point 13 can be adjusted along the X, Y, and Z orthogonal axes. The coordinates of the line are measured by moving the angle control axes, θ, and β axes of the displacement meter so that they follow the line.

〔Effect of the invention〕

As described above, according to the present invention, the structure of a non-contact displacement meter that outputs a light amount control amount, an angle sensor, a linear sensor, etc. enables the detection of lines made of different materials on a three-dimensional free curve. This has the effect of automatically measuring coordinates at high speed.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional three-dimensional measurement system, Fig. 2 is a block diagram showing an example of a system configuration to which the method of the present invention is applied, and Fig. 3 a and b are outputs from an optical displacement meter. Diagram showing the signal,
FIG. 4 is a diagram showing the movement of the laser spot of the optical displacement meter. 1...Orthogonal three-axis movement mechanism, 4...Measurement surface, 5...
... Lines made of different materials on the measurement surface, 6 ... Optical displacement meter, 7 ... Rotating shaft mechanism and its angle indexing mechanism, 8
... Coordinate calculation processor, 9 ... Supervision processor, 10 ... Inverse coordinate calculation processor, 11 ... Servo amplifier, 12 ... Laser light of optical displacement meter,
13... Laser spot. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1 In a three-dimensional measurement method that has a movement mechanism for the three-axis orthogonal coordinates of X, Y, and Z, a non-contact displacement meter that outputs a light amount control amount, and an angle control mechanism that controls the attitude of this optical displacement meter, A three-dimensional automatic measurement method characterized by measuring the coordinates of a line set on a surface while following the line.