JPH04276513A - Shape measuring and processing method - Google Patents

Abstract

PURPOSE:To improve the freedom in selecting a measuring point and a reference point by converting point-group data into curved-surface data, computing the point groups required for obtaining the difference between both curved surfaces for shape measurement and a shape reference, and operating the difference between the point groups. CONSTITUTION:Even if both or one of the measured shape data obtained by measuring the size of the shape of a work to be measured and reference shape data which are set for the work to be measured are the point group data, the point group data are converted into the curved-surface data. Therefore, both the measured shape data and th shape reference data become the shape data of the curved surfaces which are continued in three dimensions. Therefore, any position which is deviated from the positions of the point-group data of both the measured shape data and the reference shape data is selected, and the difference can be operated and displayed. Thus, the freedom in selecting the measuring point and the reference point is improved, and the quick, accurate evaluation can be performed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape measurement processing method that is used to measure the shape of a three-dimensional workpiece and appropriately display and evaluate the shape.

0002

[Prior Art] In recent years, shortening the time period for product development has become a major issue, and in order to obtain resin molded products and press molded products with the required shape accuracy, the so-called method of measuring the shape of the workpiece to be measured is Many 3D measurement methods are used.

[0003] In order to determine whether the molded product is manufactured within the required accuracy range, each measurement value Ps1 to Ps5 of the shape and dimensions of the workpiece to be measured as shown in FIG. 6 is used.
and each reference dimension Pk1 to Pk5 set for each reference position corresponding to each measurement point are compared as shown in Fig. 7 to calculate the difference, or the amount of deformation is estimated as the amount of molding deformation. In order to manufacture a mold, the difference in shape and size between the mold dimensions and the molded product is determined.

[0004] Comparative evaluation of shape dimensions and standard dimensions is as follows:
The measurement procedure and standard dimensions are taught to the three-dimensional measuring machine in advance, and each shape and dimension Ps1 to Ps for each measurement point is calculated.
Each time s5 is measured by a three-dimensional measuring machine, the difference value between the measured data Ps1 to Ps5 and the reference dimensions Pk1 to Pk5 at the corresponding position is calculated by the three-dimensional measuring machine and obtained as a printer output, and This is done by manually calculating the required parts.

[0005] Also, when calculating the difference between the obtained measurement value and the reference dimension value, or displaying the result in a graph to make it easier to understand, the measurement data Ps1 to Ps5 of each measurement point and the corresponding standards are used. Reference data Pk regarding position
It is possible to express the difference between 1 and Pk5.

[0006]

[Problem to be solved by the invention] However, the difference value between the shape dimension and the reference dimension, which is the content that is most wanted to be understood, is that both the shape measurement data and the shape reference data are usually point cloud data, and the difference value is the difference value between these points. Group data can only be obtained for the same position. In short, since geometry measurements are often performed only on point groups, the calculation of the difference value is constrained by this measurement position. Furthermore, even when the difference value is expressed in an easy-to-understand manner using a graph or the like, it is only possible to display the position where the shape and dimensions were measured.

[0007] For this reason, if there is a position that you want to focus on when calculating and displaying the difference value, it is necessary to measure the shape and dimensions so that this position becomes the measurement target, and many measurement positions must be specially set. It takes a lot of time to do that.

Furthermore, the state of the entire curved surface cannot be fully grasped, and therefore it takes a long time to set up molding conditions to obtain a resin molded product or a press molded product with the desired shape accuracy.

In view of the above points, the present invention is capable of calculating a difference value between shape measurement data and shape reference data at a desired position without being restricted by the shape measurement position, and displaying this difference value. The object of the present invention is to provide a shape measurement processing device that can perform the following steps.

0010

[Means for Solving the Problems] The first invention of the present application provides a difference between shape measurement data obtained by measuring a workpiece, both or either of which is point cloud data, and shape reference data set for the workpiece to be measured. In a shape measurement processing method that calculates the obtained difference value and displays the obtained difference value as appropriate, the point group data is converted to curved surface data, and the points necessary to take the difference between the curved surface data of the shape measurement data and the shape reference data. The method is characterized in that a group is calculated and obtained, a difference is calculated between the data of the obtained point group, and this is displayed.

[0011] The second invention of the present application further defines a color corresponding to the magnitude of the difference value between the shape measurement data and the shape reference data in the first invention, and calculates the calculated difference value based on the magnitude. It is characterized by color display.

0012

[Operation] In the above configuration of the first invention of the present application, even if the shape measurement data obtained by measuring the shape and dimensions of the workpiece to be measured and/or the shape reference data set for the measurement workpiece are point cloud data, Since this point cloud data is converted into curved surface data, both shape measurement data and shape reference data become three-dimensional continuous curved surface shape data.
Without being constrained by the position of the point cloud data, select any position of the shape measurement data and shape reference data, such as a position outside the position of the point cloud data, obtain the data of both, and calculate the difference between them. can be calculated and displayed as appropriate.

[0013] In the above configuration of the second invention of the present application, in addition to the first invention, the obtained difference value can be displayed in a color corresponding to its size, and can be used for various evaluations.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 4.

FIG. 1 shows a flowchart of a shape measurement process according to a first embodiment of the present invention. According to this,
Measurement point Ps (Xn, Yn) and reference point Pk (X
k, Yk) are not necessarily at the same position, but from the point group data on the XY plane obtained by measurement, the formula Z = f (x, y)
Convert to curved surface data PA (Xk, Yk, Zk) using
The height Za at k (Xk, Yk) is calculated. Then, a difference ZZ is found between this height Za and the reference height Zk. Here, methods for converting point cloud data to curved surface data include B-SURFACE, beige surface,
There are many methods such as polynomial approximation surface. For example, he is familiar with "Shape Processing Engineering" by Fujio Yamaguchi published by Nikkan Kogyo Shimbun.

FIG. 2 shows point group data Ps measured at grid positions parallel to the Z axis and parallel to the X and Y axes as curved surface data PA, and on this curved surface data PA parallel to the Z axis and at the XY origin. This is an example in which the measurement point Pa was determined as a value on a plane passing through the plane and forming a constant angle α with the X axis.

According to this, XY which is not actually measured
The Z-axis of the measurement point in position can be determined. Therefore, it is possible to obtain the X value, Y value, and Z value at the necessary reference position and take the difference without being restricted by the actual measurement position.

That is, it is possible to calculate the difference at any position and cross section from the minimum necessary data measurement values, and to perform evaluation based on this difference.

FIG. 3 shows measurement data Ps on the XY plane that can be expressed two-dimensionally, reference data Pk at a required position, and curved surface data PA converted from the measurement data Ps at a position corresponding to the reference data Pk. The calculated data Pa is shown. Further, FIG. 4 shows the difference value ZZ5 between the reference data Pk and the calculated data Pa at a necessary reference position on a graph.

According to this, it is possible to obtain the value of Ys at the reference position Xk, which is not actually measured.
It is possible to obtain the X value and Y value at the required reference point and take the difference.

That is, the degree of freedom in selecting measurement points and reference points is improved, and it becomes possible to evaluate differences at positions other than the measurement points after measurement.

FIG. 5 shows a second embodiment of the invention. In this embodiment, the difference value obtained in the same manner as in the first embodiment is displayed in a color corresponding to the difference amount, and a yellow region Ye and an orange region Or are displayed according to the difference amount. , a red area Re, a purple area Pu, a blue area Bl, and a light blue area Sb are displayed, respectively. Table 1 shows an example of the correspondence between the amount of difference used for coloring and the color.

[0023]

[Table 1]

According to this method, the amount of difference can be expressed three-dimensionally as a surface, so it is visually easy to understand, and it is also possible to accurately grasp subtle trends in changes that are easy to miss in numerical table-based difference evaluation.

[0025] In the present invention, even if both the shape measurement data and the shape reference data are point cloud data, by processing them by processing them into curved surfaces, it is possible to obtain arbitrary positions without being constrained by the point cloud positions of these data. You can select and calculate the data in , and obtain the difference between them.

[0026]

Effects of the Invention In the first invention of the present application, even if the shape measurement data obtained by measuring the shape and dimensions of the workpiece to be measured and/or the shape reference data set for the measurement workpiece are point cloud data, By converting point cloud data to curved surface data, both shape measurement data and shape reference data are
Since the curved surface shape data is three-dimensionally continuous, it is not restricted to the position of the point cloud data, and any position such as a position deviating from the position of the point cloud data of the shape measurement data and shape reference data can be adjusted. You can select and obtain both data, calculate the difference between them, and display this as appropriate.
The degree of freedom in selecting measurement points and reference points is improved and the operating procedure is simplified. It also enables quick and appropriate evaluation.

[0027] In the second invention of the present application, in addition to the first invention, the obtained difference value can be displayed in a color corresponding to its size, so that it can be used for various evaluations, and the difference amount can be visually displayed. It becomes easier to understand, and it is possible to accurately grasp trends in subtle changes that are easy to miss with numerical difference evaluation.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing the procedure of a first embodiment of the present invention.

FIG. 2 is a three-dimensional graph showing the relationship between point cloud data measured according to the procedure of FIG. 1, curved surface data converted therefrom, and shape and dimension data at arbitrary positions obtained from the curved surface data.

[Figure 3] Measured point cloud data obtained through the prescribed procedure in Figure 1, point cloud data about the required position, and calculated data obtained from the curved data of the measured point cloud data according to the required reference position. This is a graph showing the relationship between

FIG. 4 is a graph showing the amount of difference at each data point between the calculated data in FIG. 3 and reference data.

FIG. 5 is a three-dimensional graph showing a data display mode of a second embodiment of the present invention.

FIG. 6 is a flowchart showing a conventional procedure.

7 is a graph showing the relationship between point cloud data measured in the procedure of FIG. 6 and reference data set as point cloud data at a corresponding position; FIG.

[Explanation of symbols]

Pk standard data Ps measurement data PA surface data Pa calculation data ZZ Difference amount

Claims (2)

[Claims] [Claim 1] Calculate the difference between shape measurement data obtained by measuring a workpiece, both or either of which is point cloud data, and shape reference data set for the workpiece to be measured, and use the obtained difference value as appropriate. In the shape measurement processing method to be displayed, the point cloud data is converted to curved surface data, the point cloud necessary for taking the difference is calculated from the curved surface data of the shape measurement data and the shape reference data, and the obtained points are calculated. A shape measurement processing method characterized by calculating a difference between data of a group and displaying the difference. 2. The method according to claim 1, wherein a color corresponding to the magnitude of the difference value between the shape measurement data and the shape reference data is defined, and the calculated difference value is displayed in color based on the magnitude. shape measurement processing method.