JP2005181131A - Method for obtaining shape data of object to be measured and method for aligning shape data of object to be measured with cad data using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain the shape data of an object to be measured in a coordinate system on the basis of positioning means, such as a jig without positioning the object to be measured to the positioning means and efficiently. <P>SOLUTION: In S3, the shape of an abutting estimation range against the jig in the object to be measured is measured by a measurement instrument. In S4, a point projecting outermost in the shape data of the abutting estimation range is determined, to determine an abutting point against the jig in the object to be measured. In S5, a three-dimensional coordinate system based on the jig is set on the basis of the abutting point. In S6, the three-dimensional shape of the object to be measured in the three-dimensional coordinate system, on the basis of the jig, is measured by the measurement instrument. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for acquiring shape data of a measurement object in a coordinate system based on a positioning means such as a jig, and the position of the shape data of the measurement object and CAD (Computer Aided Design) data using the method. It is related with the method of combining.

  Conventionally, when measuring the shape of an object to be machined while being positioned on a jig, the shape of the object to be measured in the coordinate system based on the jig with the object being positioned on the jig Data is being acquired. However, when the measurement is performed in a state where the measurement object is positioned on the jig, the accuracy of the acquired shape data is reduced due to variations in manufacturing of the jig, deterioration with time, and the like. If an attempt is made to suppress a decrease in the accuracy of the shape data, the manufacturing cost of the jig will increase, and the maintenance and management of the jig will become troublesome. Therefore, there is a need for a method for acquiring the shape data of the measurement object in the coordinate system based on the jig without positioning the measurement object on the jig.

  Further, a method for aligning the shape data of the measurement object and the CAD data by associating the coordinate system of the shape data of the measurement object measured by the measuring instrument with the coordinate system of the CAD data has been proposed. An example of the alignment method is disclosed in Japanese Patent Laid-Open No. 2001-82951 (Patent Document 1). In Patent Document 1, the alignment reference plane of CAD data is associated with the target point group of the shape data of the measurement object, and the shape data of the measurement object and the CAD are set under the condition that the total distance between the target point group and the reference plane is minimized. Alignment with data is performed. By using the alignment method of Patent Document 1, it is possible to align the shape data of the measurement object and the CAD data of the jig, so that the CAD of the jig can be performed without positioning the measurement object on the jig. It becomes possible to acquire the shape data of the measurement object in the coordinate system based on the data.

JP 2001-82951 A

  However, in Patent Document 1, since the alignment of the measured object shape data and the CAD data is performed under the condition that the total distance between the target point group and the reference plane is minimized, the calculation for performing the alignment is complicated. It will become. And in patent document 1, since the alignment with CAD data is performed after acquiring the shape data of the whole measurement object, it is changed from the coordinate system of a measuring device to the coordinate system of CAD data about the shape data of the whole measurement object. Need to convert. Therefore, when trying to acquire the shape data of the measurement object in the coordinate system based on the CAD data of the jig using the alignment method of Patent Document 1, it is difficult to efficiently acquire the shape data of the measurement object. There is a problem that there is.

  The present invention provides, for example, a measurement object shape data acquisition method capable of efficiently acquiring shape data of a measurement object in a coordinate system based on positioning means such as a jig without positioning the measurement object on the positioning means. The purpose is to provide. In addition, the present invention performs positioning efficiently without positioning the measurement object on the positioning means when aligning the shape data of the measurement object and the CAD data in the coordinate system based on the positioning means. An object of the present invention is to provide a method for aligning the shape data of a measurement object and CAD data.

  A method for acquiring shape data of a measurement object according to the present invention is a method for acquiring shape data of a measurement object as shape data in a coordinate system with reference to a positioning means for positioning the measurement object. Obtaining the shape data of the predicted contact range with the means using a measuring device, determining the contact point with the positioning means in the measurement object based on the shape data of the predicted contact range using a computer, Obtaining a coordinate system based on the positioning means based on the contact point using a computer, obtaining shape data of a measurement object in the coordinate system based on the positioning means using a measuring instrument; The shape data of the measured object in the coordinate system with reference to the positioning means is used to position the measured object as the positioning means. And summarized in that for obtaining without.

  In the present invention, the shape data of the predicted contact area with the positioning means in the measurement object is acquired, and the contact point with the positioning means in the measurement object is obtained based on the shape data of the predicted contact area. Then, by obtaining a coordinate system based on the positioning means based on the contact point, a coordinate system based on the positioning means can be obtained without positioning the measurement object on the positioning means. Furthermore, since the shape data of the measurement object is acquired after setting the coordinate system based on the positioning means, it is not necessary to convert the coordinate system for the shape data of the entire measurement object. Therefore, according to the present invention, the shape data of the measurement object in the coordinate system based on the positioning means can be efficiently acquired without positioning the measurement object on the positioning means.

  In the measurement object shape data acquisition method according to the present invention, the step of obtaining the contact point is a step of obtaining, as the contact point, a point protruding outward in the shape data of the contact prediction range. You can also This simplifies the calculation for obtaining the contact point with the positioning means, so that the shape data of the measurement object in the coordinate system based on the positioning means can be acquired more efficiently.

  The shape data acquisition method of the measurement object according to the present invention may further include a step of obtaining the predicted contact range using a computer based on CAD data of the positioning means. If it carries out like this, the contact | abutting prediction range with the positioning means in a measurement object can be set accurately.

  In the alignment method of the measurement object shape data and CAD data using the measurement object shape data acquisition method according to the present invention, the coordinate system includes the coordinate system based on the positioning means, and the design data of the measurement object and the positioning means. By associating the coordinate system of CAD data with a computer, it is possible to align the shape data of the measurement object and the CAD data in the coordinate system with the positioning means as a reference. In this way, when positioning the measured object shape data and the CAD data in the coordinate system based on the positioning means, the positioning can be performed efficiently without positioning the measuring object on the positioning means. .

  Hereinafter, modes for carrying out the present invention (hereinafter referred to as embodiments) will be described with reference to the drawings.

  FIG. 1 is a diagram showing an outline of the overall configuration of a system used when a measurement object shape data acquisition method and a measurement object shape data and CAD data alignment method according to an embodiment of the present invention are performed. . The system in this embodiment includes a measurement system 10, a CAD system 12, and an alignment system 14. In FIG. 1, the systems 10, 12, and 14 are illustrated as separate ones, but these systems 10, 12, and 14 can be integrated.

  The measurement system 10 includes a measuring device 16 and a data processing device 18 and acquires three-dimensional shape data 24 of the measurement object 20. The measuring device 16 measures the three-dimensional shape of the measuring object 20 with the measuring element 16-1. The three-dimensional shape data 24 measured by the measuring device 16 is input to the data processing device 18. In FIG. 1, a contact type using a probe 16-1 is illustrated as the measuring device 16, but a non-contact type can also be used as the measuring device 16. The data processing device 18 sets the coordinate system of the three-dimensional shape data 24 measured by the measuring device 16 and controls the position of the probe 16-1 of the measuring device 16. Then, the data processing device 18 stores the three-dimensional shape data 24 measured by the measuring device 16. The data processing device 18 can be configured by a computer.

  The CAD system 12 stores CAD data 22 including three-dimensional design data of the measurement object 20 and three-dimensional design data of a jig for positioning the measurement object 20. The CAD data 22 has surface shape data, and IGES (Initial Graphics Exchange Specification) is used as an example of the format, but the format of the CAD data 22 in the present embodiment is not limited to this. The CAD system 12 can be configured by a computer.

  CAD data 22 stored in the CAD system 12 and shape data 24 of the measurement object 20 stored in the data processing device 18 are input to the alignment system 14. The alignment system 14 then aligns the shape data 24 of the measurement object 20 and the CAD data 22. The alignment system 14 can be configured by a computer.

  An example of a schematic configuration of the measurement object 20 is shown in FIG. 2, and an example of a schematic configuration of the jig 26 as a positioning means for positioning the measurement object 20 is shown in FIG. As shown in FIG. 3, the jig 26 has receiving surfaces 26-1, 26-2, 26-3 and pins 26-4 and 26-5 for positioning the measurement object 20. As shown in FIG. 2, the measurement object 20 has contact surfaces 20-1, 20-2, and 20-3 for making contact with the receiving surfaces 26-1, 26-2, and 26-3, respectively. ing. Further, the measurement object 20 is provided with holes (not shown) for passing the pins 26-4 and 26-5. In addition, the measurement object 20 here is what is machined in a state where the positioning is performed by the jig 26, for example.

  Here, as shown in FIG. 3, assuming that a three-dimensional coordinate system is set in which the horizontal direction of the jig 26 is the X direction, the front-rear direction is the Y direction, and the vertical direction is the Z direction, the receiving surface 26-1 is set. , 26-2, 26-3, the measuring object 20 is positioned in the Z direction. Then, the measurement object 20 is positioned in the X and Y directions by the pin 26-4, and the measurement object 20 is positioned in the Y direction by the pin 26-5. As described above, positioning of the measurement object 20 with respect to the jig 26 is performed. Note that the contact surfaces 20-1, 20-2, and 20-3 of the measurement object 20 are not necessarily uniform flat surfaces, but have a slight surface roughness. Therefore, when the measurement object 20 is positioned on the jig 26, a certain point on the contact surface 20-1 contacts the receiving surface 26-1. Similarly, a point on the contact surface 20-2 contacts the receiving surface 26-2, and a point on the contact surface 20-3 contacts the receiving surface 26-3.

  In the present embodiment, the measurement system 10 acquires the shape data 24 of the measurement object 20 in the three-dimensional coordinate system based on the jig 26 without positioning the measurement object 20 on the jig 26. Then, the alignment system 14 aligns the shape data 24 of the measurement object 20 and the CAD data 22 in the three-dimensional coordinate system with the jig 26 as a reference. Hereinafter, details of a method for realizing this will be described with reference to a flowchart shown in FIG.

  First, in step (hereinafter referred to as S) 1, the data processing device 18 specifies a predicted contact range of the measured object 20 with the jig 26. The predicted contact range here can be set based on the CAD data of the jig 26. For example, the data processor 18 reads the CAD data 22 from the CAD system 12, and the CAD data of the contact surfaces 20-1, 20-2 and 20-3 on the measurement object 20 and the receiving surfaces 26-1 and 26-26 on the jig 26. 2 and 26-3, the contact prediction ranges 20-4, 20-5, and 20-6 can be set, respectively, as shown in FIG. Then, the process proceeds to S2.

  In S <b> 2, the data processing device 18 sets a temporary reference for measuring the shapes of the contact predicted ranges 20-4, 20-5, and 20-6 of the measurement object 20 with the jig 26. As a temporary reference here, for example, an arbitrary point in each of the contact prediction ranges 20-4, 20-5, and 20-6 can be measured, and the measurement point data can be used as a temporary reference. Then, the process proceeds to S3.

  In S <b> 3, the shape of the predicted contact range 20-4, 20-5, and 20-6 with the jig 26 in the measurement object 20 is measured by the measuring device 16. Here, FIG. 2 shows an example of the measurement points 20-7, 20-8, and 20-9 set in the contact prediction ranges 20-4, 20-5, and 20-6, respectively. However, the measurement points 20-7, 20-8, and 20-9 can be arbitrarily set within the contact prediction ranges 20-4, 20-5, and 20-6, respectively. The shape data of the contact prediction ranges 20-4, 20-5, and 20-6 measured by the measuring device 16, that is, the three-dimensional data of the measurement points 20-7, 20-8, and 20-9, is stored in the data processing device 18. Is input. Then, the process proceeds to S4.

  In S <b> 4, the contact point of the measurement object 20 with the jig 26 is obtained by the data processing device 18. The contact point here is obtained based on the shape data of the contact prediction ranges 20-4, 20-5, and 20-6, that is, the three-dimensional data of the measurement points 20-7, 20-8, and 20-9. . For example, as shown in FIG. 5, the point 30-1 that protrudes to the outermost side, that is, the jig side among the measurement points 20-7 can be a contact point with the receiving surface 26-1. Similarly, the point 30-2 that protrudes to the outermost side, that is, the jig side among the measurement points 20-8 can be set as the contact point with the receiving surface 26-2, and is the most among the measurement points 20-9. The point 30-3 protruding to the outside, that is, the jig side can be used as a contact point with the receiving surface 26-3. However, in this embodiment, since the measurement object 20 is not positioned on the jig 26, the receiving surfaces 26-1, 26-2, 26-3 of the jig 26 and the three-dimensional (XYZ) of the jig 26 in FIG. ) The coordinate system is illustrated as a virtual one. Then, the process proceeds to S5.

  In S <b> 5, the data processing device 18 determines a three-dimensional coordinate system based on the jig 26 for measuring the shape of the measurement object 20. Since the contact points 30-1, 30-2, and 30-3 with the receiving surfaces 26-1, 26-2, and 26-3 of the jig 26 are obtained in S4, these contact points 30-1, A reference plane based on 30-2 and 30-3 is determined, and a three-dimensional coordinate system based on the jig 26 can be set based on the reference plane. For example, as shown in FIG. 5, the X direction (the jig 26 left-right direction) and the Y direction (the jig 26 front-back direction) are parallel to the reference plane based on the contact points 30-1, 30-2, 30-3. It is possible to set the Z direction (the vertical direction of the jig 26) in the direction perpendicular to the reference plane. Then, the process proceeds to S6.

  In S <b> 6, the shape of the measuring object 20 in the three-dimensional coordinate system with the jig 26 as a reference is measured by the measuring device 16. The three-dimensional shape data 24 of the measurement object 20 measured by the measuring instrument 16 is input to the data processing device 18. Then, the process proceeds to S7.

  In S 7, the alignment system 14 aligns the shape data 24 of the measurement object 20 and the CAD data 22 in the three-dimensional coordinate system with the jig 26 as a reference. The alignment here is performed by associating the three-dimensional coordinate system based on the jig 26 with the three-dimensional coordinate system of the CAD data 22. For example, when the three-dimensional coordinate system of the CAD data 22 is as shown in FIG. 3, when the X direction is the left and right direction of the jig 26, the Y direction is the front and rear direction of the jig 26, and the Z direction is the vertical direction of the jig 26, By aligning the three-dimensional coordinate system based on the jig 26 with the three-dimensional coordinate system of the CAD data 22, the shape data 24 of the measurement object 20 and the CAD data 22 can be aligned.

  After the three-dimensional coordinate system based on the jig 26 is associated with the three-dimensional coordinate system of the CAD data 22, the shape data 24 of the measurement object 20 and the CAD data of the measurement object 20 are converted into the coordinates of the CAD data 22. By performing the analysis to be compared in the system by the alignment system 14, it is possible to inspect whether the measured measurement object 20 is manufactured according to the CAD data 22.

  Further, with respect to the shape data 24 of the measurement object 20 and the CAD data of the jig 26, the interference system other than the contact part is inspected by the alignment system 14 to measure the shape of the measurement object 20 actually manufactured. The interference state between the object 20 and the jig 26 can be inspected, and the necessity of design change of the jig 26 can be determined based on the inspection result.

  As described above, in this embodiment, the shapes of the contact prediction ranges 20-4, 20-5, and 20-6 with the jig 26 in the measurement object 20 are measured, and the contact prediction ranges 20-4. , 20-5, 20-6, contact points 30-1, 30-2, and 30-3 with the jig 26 in the measurement object 20 are obtained based on the measurement points 20-7, 20-8, and 20-9. ing. Then, by obtaining a three-dimensional coordinate system based on the jig 26 based on the contact points 30-1, 30-2, and 30-3, the workpiece 26 is not positioned on the jig 26. A three-dimensional coordinate system with reference to can be obtained. Furthermore, since the three-dimensional shape of the measurement object 20 is measured after setting the three-dimensional coordinate system based on the jig 26, it is not necessary to convert the coordinate system for the shape data 24 of the entire measurement object 20. Therefore, according to the present embodiment, the shape data 24 of the measurement object 20 in the three-dimensional coordinate system with the jig 26 as a reference can be efficiently acquired. At this time, since it is not necessary to position the measurement object 20 on the jig 26, the shape of the measurement object 20 in the three-dimensional coordinate system with the jig 26 as a reference can be measured with high accuracy. Then, by aligning the shape data 24 of the measurement object 20 and the CAD data 22 in the three-dimensional coordinate system with the jig 26 as a reference, the alignment of the shape data 24 of the measurement object 20 and the CAD data 22 is performed. It can be performed accurately and efficiently.

  Furthermore, in the present embodiment, the measurement points 20-7, 20-8, and 20-9 in the predicted contact ranges 20-4, 20-5, and 20-6 are projected to the outermost side, that is, the jig side. By calculating the points 30-1, 30-2, 30-3 as contact points with the jig 26, the calculation for determining the contact points 30-1, 30-2, 30-3 with the jig 26 is performed. It can be simplified. Therefore, the shape data 24 of the measurement object 20 in the three-dimensional coordinate system with the jig 26 as a reference can be acquired more efficiently.

  In the above description, the contact points 30-1, 30-2, 30-3 in the vertical direction of the jig 26 are obtained, and the jig 26 is based on these contact points 30-1, 30-2, 30-3. The case where the three-dimensional coordinate system with reference to is set has been described. However, it is also possible to obtain contact points in the left-right direction and the front-rear direction of the jig 26 by a similar method, and to set a three-dimensional coordinate system based on the jig 26 based on these contact points.

  As mentioned above, although the form for implementing this invention was demonstrated, this invention is not limited to such embodiment at all, and it can implement with a various form in the range which does not deviate from the summary of this invention. Of course.

It is a figure which shows the outline of the whole structure of the system used when implementing the shape data acquisition method of the measured object which concerns on embodiment of this invention, and the positioning method of the shape data and CAD data of a measured object. It is a figure which shows an example of schematic structure of a measurement object. It is a figure which shows an example of schematic structure of the jig | tool which positions the measurement object. It is a flowchart explaining the shape data acquisition method of the measurement object which concerns on embodiment of this invention, and the alignment method of shape data of a measurement object, and CAD data. It is a figure explaining the method of calculating | requiring the contact point with the jig | tool in a measurement object.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Measurement system, 12 CAD system, 14 Positioning system, 16 Measuring device, 18 Data processing device, 20 Measurement object, 20-1, 20-2, 20-3 Contact surface, 20-4, 20-5, 20- 6 Predicted contact range, 20-7, 20-8, 20-9 Measurement point, 22 CAD data, 24 Shape data, 26 Jig, 26-1, 26-2, 26-3 Receiving surface, 30-1, 30-2, 30-3 Contact point.

Claims (4)

A method for acquiring shape data of a measurement object as shape data in a coordinate system based on a positioning means for positioning the measurement object,
Acquiring shape data of a predicted contact range with a positioning means in a measurement object using a measuring instrument;
Obtaining a contact point with the positioning means in the measurement object based on the shape data of the predicted contact range using a computer;
Using a computer to determine a coordinate system based on the positioning means based on the contact point;
Obtaining shape data of a measurement object in a coordinate system based on the positioning means using a measuring instrument;
Thus, the shape data of the measurement object is obtained without positioning the measurement object on the positioning means in the coordinate system based on the positioning means. A method for obtaining shape data of a measurement object according to claim 1,
The method for obtaining shape data of a measurement object is characterized in that the step of obtaining the contact point is a step of obtaining, as the contact point, a point that protrudes outward in the shape data of the predicted contact range. A method for acquiring shape data of a measurement object according to claim 1 or 2,
A method for obtaining shape data of an object to be measured, further comprising the step of obtaining the predicted contact range using a computer based on CAD data of a positioning means. A method of aligning the shape data of the measurement object and the CAD data using the method of acquiring the shape data of the measurement object according to any one of claims 1 to 3,
By associating the coordinate system based on the positioning means with the coordinate system of CAD data including design data of the measured object and the positioning means using a computer, the measurement object in the coordinate system based on the positioning means A method for aligning shape data of a measurement object and CAD data, wherein the shape data and CAD data are aligned.

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