JPS63244203A - Measuring point data obtaining method - Google Patents

Abstract

PURPOSE:To automatically obtain a measuring point data required for a working program at a high speed, thinning out the measuring point data in accordance with the curvature of a working line. CONSTITUTION:A profile measuring and calculating part 40 outputs a weaving coordinate signal W to an NC control part 30, based on a position detecting signal L, a height detecting signal H and a singular line detecting signal D, an also, inputs a measuring point data for showing a position and an attitude of singular line T provided along a working line of a work, as a singular line position and attitude signal C to a data processing part 50. The data processing part 50 calculates a distance between a straight line for connecting the measuring points Pi, Pk and a measuring point Pj existing between the measuring points Pi, Pk, and when the calculated distance is smaller than an allowable value which has been set in advance, its measuring point Pj is thinned out. In such a way, a measuring point data for a working program R can be obtained at a high speed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for acquiring measurement point data of a machining line on a workpiece, and in particular to measurement point data that can thin out measurement point data according to the curvature of a machining line. This is related to the acquisition method.

[Prior Art] It has been well known that a workpiece is cut or welded using a laser beam or the like, and in general, a teaching method is used in which a machining line on a workpiece is taught in advance and the workpiece is machined in accordance with the teaching. A playback method is used.

In order to perform this teaching, conventionally, an operator manually inputs the position and orientation of the processing head one point at a time while driving the main body of the processing machine. However, this teaching operation usually takes several hours, depending on the shape and length of the processed line.

A machining program is generated based on the measurement point data thus obtained, and desired machining is performed along the machining line.

[Problems to be solved by the invention] As described above, in the conventional measurement point data acquisition method, processing lines were input manually by the operator.
There was a problem in that it required a lot of time and effort.

This invention was made to solve the above problems, and it is possible to automatically and quickly obtain the measurement point data necessary for the machining program by thinning out the measurement point data according to the curvature of the machining line. The purpose of this study is to obtain a measurement point data acquisition method that enables the following.

[Means for Solving the Problems] The measurement point data acquisition method according to the present invention includes a first step of automatically following a machining line and determining the positions and orientations of a plurality of measurement points on the machining line; a second step for distinguishing teaching points and detection points included in the measurement point data, and a third step for setting a measurement point sequence block from the measurement point data;
A fourth step of thinning out the detection points in the measurement point sequence block is provided.

[Operation] In the present invention, teaching points included in the measurement points are determined, measurement point sequence blocks are set, and measurement point data for the machining program is acquired after thinning processing.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figure is a block diagram showing a processing device to which an embodiment of the present invention is applied.

In the figure, (10) is a three-dimensionally movable processing machine body, which is equipped with a plurality of (for example, 5 motors corresponding to the 5 axes of X to Z, α, and β) (not shown), and each motor Based on the rotational position, the arm tip (10) of the processing machine main body (10)
It outputs a position detection signal indicating the position and orientation of a).

T is a singular line provided along the processing line of the workpiece,
For example, it consists of a non-reflective black tape with a width of 0.4 mm that is pasted on the processing line.

(20) is a sensor head attached to the tip of the arm (10m), which detects a semiconductor laser that emits infrared laser light (see broken line) and a semiconductor device that receives reflected laser light that is diffusely reflected on the surface of the workpiece. It is composed of a well-known optical sensor having a device and outputs a height detection signal I indicating the height to the workpiece and a singular line detection signal indicating the existence of a singular line T.

(30) is an NC control section that outputs a drive signal M for driving the processing machine main body (10). (40) is a tracing measurement calculation unit for weaving the arm tip (10a) along the singular line T, which outputs a position detection signal;
Based on the height detection signal H and the singular line detection signal, the weaving coordinate signal W used for the weaving operation is N
C control unit (30), and also outputs measurement point data indicating the position and orientation of the singular line T, that is, a singular line position and orientation signal C.

(50) is a data processing unit that generates a machining program R based on the singular line position/orientation signal C, and (60) is an NC unit that generates initial setting commands, operation commands, etc. when driving the processing machine main body (10).
An operation panel ( ) O is used to input the input to the control unit (30), and a teaching box ( ) is used to input drive commands for the processing machine main body (10) and the like to the NC control unit (30).

Next, referring to the block diagram of FIG. 1, the explanatory diagram of FIG. 2 showing the weaving operation, the flowchart diagram of FIG. 3, and the explanatory diagram of FIG. Let's discuss an example.

First, a singular line T is formed on the processing line of the workpiece, a sensor head (20) is installed at the arm tip (10a), and the operation is performed!
(60) to put the NC control section (30) into teaching mode.

Also, input the starting point Ps, direction indicating point PD, and ending point P of the singular line T via the teaching box (70), and also input the weaving width -D (usually about 101) and the pitch 1 for weaving operation (usually, Initialize the number III).

Then, the NC control unit (30) is activated via the operation panel (60) to carry out tracing measurement (weaving operation) for automatic teaching as shown in FIG. A series of measurement point data indicating the positions and orientations of P1 to Pn is obtained (first step S1).

That is, the irradiation point of the laser beam from the sensor head (20) is moved from the starting point Ps in a direction perpendicular to the direction indicating point 1'o, the intersection with the singular line T, that is, the measurement point P, is detected, and then the point The point that has moved by a fixed amount is defined as the first weaving injection. The starting point Ps and the first weaving point Q1 are folded back along the straight line connecting the first weaving point Q1.Although they are shown spaced apart for convenience, the measurement point P1' coincides with the measurement point P1), and the predetermined amount (
The moved point (corresponding to the weaving width - 0) is defined as the second weaving point q2.

Next, the optical spot of the laser beam is tilted by a predetermined pitch l toward the direction indicating point PD and moved to the third weaving point Q, and hereafter, weaving points Q6, q6, .
...While tracing the singular line T on the machining line by turning back one by one, measurement points P1 to Pn are detected until reaching the vicinity of the end point PB.

Note that during the weaving operation, the tracing measurement calculation unit (40) calculates the position of the next weaving point Qi+z based on the currently detected measurement point Pi, the previously detected measurement point Pi-1, and the weaving points Qi and Qi+1. and a weaving signal W indicating the attitude, and sends this to the NC control unit (3
0). Therefore, the sensor head (20) is always held so that the height to the workpiece is constant and the optical axis is substantially perpendicular to the tracing surface including the singular line T.

In addition, if automatic copying operation becomes impossible during weaving operation due to an inconvenience in the shape of the workpiece, the mode is switched to manual mode and the measurement points are taught, so measurement points P1 to Pn are automatically scanned by the copying operation. It includes detected detection points and manually taught teaching points.

In order to distinguish these teaching points and detection points, the measurement point data storage section in the scanning measurement calculation section (40) sets a flag in the control word of the teaching point data, and stores the measurement point data as a singular line position/orientation signal C. Input to the processing unit (50) (second step S2).

Next, the data processing unit (50) sets a measurement point sequence block with measurement point data (third step S3).

That is, it is determined whether the data start point of the measurement point data is a detection point or not (Step 531). If it is a detection point, the data start point is set as the block start point (Step 532). If it is not a detection point but a teaching point, The measurement point data is incremented until the detection point appears, and the teaching point immediately before the first detection point appears is set as the block start point (step 533).
Furthermore, it is determined whether or not there is a teaching point after the block start point (step 534). If there is a teaching point, the first teaching point that appears is set as the block end point (step 535). If there is no teaching point, the measuring point is The data end point of the data is set as the block end point (step 536). Here, the teaching point and the detection point can be distinguished by the presence or absence of a flag.

Thereafter, steps S31 to S36 are repeated to sequentially set measurement point sequence blocks, and when the data end point of the measurement point data is reached, the third step S3 is ended.

Next, detection point thinning processing is performed for each measurement point sequence block (fourth step S4).

Here, an example will be explained in which one measurement point sequence block is composed of measurement points P, .about.P, as shown in FIG. 4.

First, consider a straight line connecting measurement point P, (data starting point) and measurement point P, and calculate the distance between this straight line and measurement point P2 that exists between measurement points P, P, and P.

-Finally, if the position vectors of each measurement point Pi-Pj, r'k (i<j<k) are Xi, Xj, Xk, and Aik=Xk-Xi Bij=Xj-Xi, then the measurement point Pi, Straight line connecting f'k and measurement point Pj
The distance between h=[l Bij I 2(^1k4ij/ l^ik
l )2]1/2.

Next, it is determined whether the distance calculated in this way is smaller than a preset tolerance value ε, and if it is smaller than the tolerance value ε, a straight line connecting measurement points P and P4 is further considered, and this straight line and the measurement point The distance to each measurement point P3, P, existing between P, ,P, is calculated. This calculation judgment operation is performed when the distance between the straight line connecting two measurement points and the measurement point existing between them is
This continues until even one of them exceeds the tolerance value ε.

In the example of FIG. 4, there is a measurement point P4 whose distance is greater than or equal to the allowable value ε with respect to the straight line connecting the measurement points Pl and P@. Therefore, the measurement point P is left as the measurement point data, and the measurement point P
2 to P are thinned out.

Subsequently, the same calculation and determination operation is repeated using the measurement point P as a reference, and ends when the measurement point Pt (block end point) is reached. In this case, the measurement points P6 are further thinned out, and the measurement point sequence block consisting of measurement points P1 to P7 is approximated by three measurement points P1, Pl, and P.

Generally, when there is a measurement point with a distance greater than or equal to the allowable value ε for the first time between the straight line connecting measurement points P: and Pk, -, is thinned out from measurement points Pi to I', and measurement points Pk-, is based on the following criteria.

When the thinning process for one measurement point sequence block is completed in this way, the thinning process for the next measurement point sequence block is performed sequentially.However, as is clear from the third step S3, the data starting point of the measurement point data, the data The end point and teaching point will always remain as measurement point data after thinning.

Then, the data processing unit (50) generates a machining program R for machining the workpiece along the machining line based on the measurement point data after the thinning process, and converts this to N Cft1l.
The data is stored in a non-volatile memory (not shown) in the J control section (30). At this time, since the amount of measurement point data is reduced by the thinning process, memory capacity can be saved and the data processing section (50) can generate a machining program at high speed.

Thereafter, a processing head (not shown) is attached to the arm tip (10a) of the processing machine main body (10), and the processing head is driven by a drive signal M based on a processing program R.
Perform a predetermined welding or cutting operation.

[Effects of the Invention] As described above, according to the present invention, a first step of automatically following a machining line and determining the positions and orientations of a plurality of measurement points on the machining line, and a teaching point and a teaching point included in the measurement points are performed. A second step for distinguishing the detection points, a third step for setting a measurement point sequence block from the measurement point data, and a fourth step for thinning out the detection points in the measurement point sequence block are provided. The teaching points included in the process are determined, the measurement point sequence block is set, and the measurement point data for the machining program is acquired after the thinning process, which has the effect of providing an automatic and high-speed measurement point data acquisition method. be.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a weaving operation according to the present invention, and FIG.
The figure is a flowchart for explaining one embodiment of the present invention, and FIG. 4 is an explanatory diagram showing the thinning processing operation according to the present invention. (10m)...Arm tip (20)...Sensor head R...Machining program P1-Pn...Measurement point C...Special 14 line position/posture signal (measurement point data) S
l...First step Sl...Second step S
3...Third step S4...Fourth step In the figures, the same reference numerals indicate the same or corresponding parts. Figure 2 Qn Figure 3

Claims (3)

[Claims] (1) A first step of automatically following the machining line using a sensor head provided at the tip of the arm and determining the positions and orientations of a plurality of measurement points on the machining line; and teaching included in the measurement points. a second step for distinguishing points and detection points; and a third step for setting a measurement point sequence block from the measurement point data.
and a fourth step of thinning out detection points in the measurement point sequence block, and generating a machining program for machining the workpiece based on the measurement point data after the thinning process. Data acquisition method. (2) The measurement point data acquisition method according to claim 1, wherein the second step includes providing a flag in a control word of the teaching point data. (3) The third step is a step of determining whether the data start point of the measurement point data is a detection point, and if the data start point is a detection point, the data start point is set as a block start point, and the data start point is a teaching point. In the case of a point, the teaching point immediately before the first detection point appears is set as the block starting point, the step of determining whether there is a teaching point after the block starting point, and if there is a teaching point, the teaching point is displayed first. The measuring point according to claim 1 or 2, characterized in that the method comprises the steps of: setting a teaching point that is received as a block end point, and setting a data end point of the measurement point as a block end point if there is no teaching point. Data acquisition method.