METHOD FOR CORRECTING DEVIATIONS IN A PRODUCTION PROCESS OF AN ARTICLE

Abstract

A method for correcting deviations in a production process of an article, including: a) measuring surface coordinates of a first article, b) representing, in three dimensions, real measurement values from measuring the surface coordinates with a display apparatus that is fastenable or fastened to a user's head, c) representing, in three dimensions, a predefined model of the article using the display apparatus, d) comparing the predefined model to the point cloud or the point mesh, e) selecting at least one region from the point cloud or the point mesh which deviates from the predefined model, f) manipulating this region of the point cloud or the point mesh by means of the gesture or head movement control such that the point cloud or the point mesh in this region is matched to the predefined model, or approximated to the predefined model, or moved beyond the predefined model, g) transmitting at least one value of a deviation between the point cloud or the point mesh and the point cloud/point mesh obtained by manipulation to a production machine or a machine for shaping tool production, or transmitting the point cloud/point mesh obtained by manipulation to the production machine or to the machine for shaping tool production, h) producing a further article in the production machine or producing or post-processing of a shaping tool for producing the further article, wherein the deviation is corrected or compensated, or based on the point cloud/point mesh obtained by the manipulation.

Claims

1. A method for correcting deviations in a production process of an article, including: a) measuring surface coordinates of a first article, b) representing, in three dimensions, real measurement values from the measuring of the surface coordinates with a display apparatus that is fastenable or fastened to a user's head, in the form of a point cloud or a point mesh, wherein the display apparatus has a gesture or head movement control for manipulating displayed representations, c) representing, in three dimensions, a predefined model of the article using the display apparatus, d) comparing the predefined model to the point cloud or the point mesh, e) selecting at least one region from the point cloud or the point mesh which deviates from the predefined model, f) manipulating this region of the point cloud or the point mesh by means of the gesture or head movement control such that the point cloud or the point mesh in this region is i) matched to the predefined model or ii) approximated to the predefined model or iii) moved beyond the predefined model such that the point cloud or the point mesh deviates in an opposite direction to previously, g) transmitting at least one value of a deviation between the point cloud or the point mesh, which was obtained from the real measurement values, and the point cloud/point mesh obtained by manipulation to a computer-controlled production machine or a machine for shaping tool production or shaping tool processing, or transmitting the point cloud/point mesh obtained by manipulation to the production machine or to the machine for shaping tool production or shaping tool processing, and h) producing a further article in the production machine or producing a post-processing of a shaping tool for producing the further article, wherein the deviation is corrected or compensated, or based on the point cloud/point mesh obtained by the manipulation.

2. The method as claimed in claim 1, wherein the measurement of surface coordinates of the article in step a) is effectuated multiple times and the real measurement values from a plurality of measurements are subject to statistical averaging and an averaged point cloud or an averaged point mesh is obtained therefrom in step b), said averaged point cloud or averaged point mesh forming the basis for the further method steps.

3. The method as claimed in claim 1, wherein the measuring of surface coordinates of the article is effectuated with a coordinate measuring machine that measures in a tactile or optical manner, a computed tomography scanner or an optical surface measuring machine.

4. The method as claimed in claim 1, wherein values of deviations which lie below a defined minimum value are ignored.

5. The method as claimed in claim 1, wherein the three-dimensional representation is effectuated as a projection, pixel representation or hologram.

6. The method as claimed in claim 1, wherein a surface is placed through the real measurement values of the point cloud or through the point mesh such that a surface representation of the article is obtained, and method steps d)-g) are as follows: d) comparing the predefined model with the surface representation, e) selecting at least one region from the surface representation which deviates from the predefined model, f) manipulating this region of the surface representation by means of the gestural or head movement control such that real measurement values in this region are matched or approximated to the predefined model, and g) ascertaining at least one value of a deviation between the surface representation and the manipulated surface representation.

7. The method as claimed in claim 1, wherein the deviation is corrected during the production or the post-processing of the shaping tool in such a way that the newly produced or post-processed shaping tool has a shape deviation from the predefined model which is directed in an opposite direction to the deviation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0072] The invention is described below on the basis of exemplary embodiments. In the drawings:

[0073] FIG. 1 shows a method sequence according to the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0074] FIG. 1 highlights a method sequence according to the invention. The first article 2, here in the form of a cube, is measured using the coordinate measuring machine 1. The coordinate measuring machine 1 is coupled to the measurement computer 3, the display apparatus 4 being coupled to the latter. This display apparatus 4 is configured in the form of 3D smart-glasses, which can be put on by a user of the CMM 1. The display apparatus 4 has a device (not illustrated in any more detail) for gesture or head movement control, by means of which seen content can be manipulated, for example displaced or deformed, by gestures or head movements.

[0075] Measurement values obtained from measuring the coordinates of the article 2 are illustrated in a point cloud 5 in step S2. The point cloud 5 is formed from the individual measurement values and consequently represents the form of the cuboid 2 as a point cloud. Exemplary measurement values are denoted by the reference sign 8. Dashed lines, which represent the edges, but are not part of the point cloud and only serve for illustrative purposes, are plotted for illustrative purposes. However, it is possible likewise to present such auxiliary lines or areas, which form the side faces of the cuboid and in or on which the measurement values lie, by means of image processing measures. The point cloud 5 is represented in three-dimensional fashion in the display device 4 and consequently placed directly in front of the eyes of the user.

[0076] A predefined model 6, for example a CAD model of the article 2, is likewise presented on the display device 4 in step S3. The illustrations from step S and step S3 can be placed on top of one another. Then, the image from step S4 emerges, in which a comparison is undertaken between the predefined model 6 and the point cloud 5.

[0077] In step S4, the point cloud 5 is illustrated on the basis of the dashed edge lines in order to make the illustration clearer. It is clear from step S4 that the point cloud 5 and the predefined model 6 deviate from one another. For illustrative purposes, the deviation is presented in an extreme manner and, in practice, it is generally less. Two edge lengths of the article 2, in the x- and y-directions according to the coordinate system specified above, are shorter than in the predefined model 6.

[0078] Subsequently, the point cloud 5 is manipulated and a region of the point cloud is selected in steps S5 and S6 and this region is matched to the predefined model 6 until the point cloud 5 and the predefined model 6 are congruent, as illustrated bottom right in FIG. 1. Instead of matching, there can be an approximation until a deviation lies within a predetermined tolerance.

[0079] The point cloud 5 may be present as a surface representation when surfaces were placed through the points in order to create a graphically represented closed body. Expressed differently, the point cloud then is also available in the form of a cuboid which, in the x- and y-directions, has different edge lengths than the predefined model 6. A manipulation can be undertaken accordingly on this cuboid obtained from the point cloud.

[0080] The representations in steps S4, S5 and S6, as shown in FIG. 1, are effectuated on the display device 4. The manipulation in step S6 is effectuated by means of a head or gesture control, in particular by means of the hand.

[0081] In step S7, the edge length deviations X and Y are evaluated according to the value. In general, steps in the method can be carried out more or less simultaneously. If it is expedient, sequences of steps may also be modified. By way of example, step S7 may occur before steps S5 and S6, in particular simultaneously with step S4 as well.

[0082] The deviation values X and Y ascertained in step S7 are transmitted to the production machine 7 in step S8, which is effectuated from the measurement computer 3 of the coordinate measuring machine 1 to the production machine 7 by a data transfer device 8. The data transfer device 8 can be a wire-based or radio-based data transfer line.

[0083] The production process is corrected in the production machine 7, i.e. the edge lengths in the x- and y-directions are corrected on the basis of the determined deviations X and Y and further articles 2 are produced in step S9, said further articles having been corrected in relation to the article 2. The article 2 also originated from the production machine 7, or was produced by the latter.