JP2007193552A - Apparatus and method for creating plane model - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for accurately creating a tool reference plane model. <P>SOLUTION: An apparatus for creating a tool reference plane model includes: a means for defining a three-dimensional lattice in a three-dimensional space in which a machining plane is disposed, inverting and placing a tool shape at each representative point on the machining surface, and creating inverted tool lattice data describing unit three-dimensional lattice group areas where the tool shapes exist and inverted distance field data describing the value of a distance to a tool shape boundary for each lattice point belonging to a unit three-dimensional lattice group through which the tool shape boundary passes; a means for combining the unit three-dimensional lattice group areas of each inverted tool lattice data and creating combined lattice data describing the unit three-dimensional lattice group located at the boundary of the combined areas; a means for creating combined distance field data describing the minimum distance value among a group of inverted distance field data, for each lattice point belonging to the unit three-dimensional lattice group of the combined lattice data; and a means for creating the tool reference plane model based on the distance value described by the combined distance field data for each lattice point. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technology for creating a surface model used in NC machining technology (numerical control machining technology). In particular, the present invention relates to a technique for creating a tool reference surface model that defines a tool path for forming a processed surface on a material based on processed surface data describing the processed surface. The present invention also relates to a technique for creating a machining surface model formed on a material by a tool that moves along a tool path based on tool path data describing a tool path.

The NC machining technique forms a predetermined machining surface on the material by relatively moving the tool and the material along a movement path taught in advance. The shape of the machined surface is represented by machined surface data created using a three-dimensional CAD (Computer Aided Design) apparatus or the like. In order to form a machining surface on a material using an NC machine tool, it is necessary to determine a movement path of the tool based on machining surface data describing the machining surface.
In the NC machining technique, a reference point is defined for a tool in order to describe the position of the tool with coordinates. Thereby, the movement path of the tool is determined by the movement path of the reference point of the tool. The movement path of the tool is equal to the path along which the tool reference point moves when the tool cutting edge surface is moved while being in contact with the machining surface. That is, the movement path of the tool is located on a surface offset by the tool shape from the machining surface. This offset surface is called a tool reference surface. In order to determine the movement path of the tool, it is necessary to create a tool reference surface model based on the machining surface data describing the machining surface.
Patent Document 1 describes a technique for creating a tool reference plane model using an inverse offset method. In the reverse offset method, a virtual reversing tool is created by approximating the machining surface with an approximate element such as a point cloud or stereo plane group (STL: Stereo lithography), and reversing the tool shape with respect to the machining posture. It arranges so that it may be located in each approximate element. Then, a tool reference surface model is created by obtaining an envelope surface of the arranged virtual reversal tool shape group.
JP-A-4-133103

In the technique of Patent Document 1, since a machining surface described by a curved surface or the like cannot be directly handled, it is necessary to calculate a tool reference surface based on an approximate model obtained by approximating the machining surface with an approximate element group. Therefore, an error caused by the approximation process occurs in the created tool reference plane model. In order to reduce this error, it is necessary to finely approximate the machining surface, but the calculation load increases as finer approximation processing is performed. There is a need for a technique for accurately creating a tool reference plane model without using an approximate model.
Further, in the NC machining technology, for example, in order to evaluate a tool path prior to actual machining, a technique for accurately creating a model of a machining surface formed on a material based on tool path data is required. Yes.
The present invention solves the above problems. The present invention provides a technique for accurately creating a tool reference surface model and a machining surface model.

The technology of the present invention can be embodied in an apparatus that creates a tool reference surface model that determines a path of a tool for processing a processed surface into a material based on processed surface data describing the processed surface. . The tool reference plane model creation device includes a machining surface data storage unit, a tool shape data storage unit, a machining surface grid data creation unit, a transposition tool grid data and a transposition distance field data creation unit, Means for creating merged grid data, means for creating merged distance field data, and means for creating a tool reference plane model.
The processed surface data describes a three-dimensional space in which processed surfaces are arranged. The tool shape data describes the tool shape with reference to the tool reference point.
The processing surface grid data is created by dividing the 3D grid into the 3D space described by the machining surface data, identifying the unit 3D grid through which the machining surface passes, and on the machining surface in the unit 3D grid. Then, a representative point is determined, and processed surface lattice data is created in which the identified unit three-dimensional lattice group and the determined representative point group are associated with each other.
The means for creating the transposed tool grid data and the transposed distance field data includes a tool reference point with the tool shape described in the tool shape data as a representative point on the machining surface in a three-dimensional space defining the three-dimensional grid. The unit 3D lattice group through which the tool shape boundary passes is specified and the tool is determined from each lattice point belonging to the unit 3D lattice group. Displacement tool grid data describing the unit 3D grid group area where the tool shape exists, and the distance value to describe the distance value to the grid point by calculating the distance value to the boundary of the shape. Create data. Here, the transposition tool grid data and the transposition distance field data are created for each representative point described in the machining plane grid data.
The means to create the merged grid data is to identify the unit 3D grid group located at the boundary of the merged unit 3D grid group area by merging the unit 3D grid group areas described in each of the transposed tool grid data groups Then, merged grid data describing the specified unit 3D grid group is created.
The means for creating the merged distance field data is the minimum value of the distance values described in association with the transposed distance field data group for each grid point belonging to the unit 3D grid group described in the merged grid data. And the merged distance field data describing the identified distance value in association with the position of the grid point is created.
The means for creating a tool reference plane model creates a tool reference plane model based on the positions of grid points and distance values described in the merged distance field data.

The tool reference plane model creation apparatus first partitions a three-dimensional lattice in a three-dimensional space in which a machining surface is arranged, specifies a unit three-dimensional lattice group through which the machining surface passes, and stores the unit three-dimensional lattice in the unit three-dimensional lattice. A representative point is determined on the processing surface. By defining the representative point for each unit three-dimensional lattice through which the processing surface passes, the representative point on the processing surface can be determined relatively evenly in each direction of the three-dimensional space. Thereby, the processing surface which spreads in various directions can be handled.
Next, the tool reference surface model creation device creates transposed tool grid data and transposed distance field data for each representative point determined on the machining surface. Transposed tool grid data and transposed distance field data represent the tool shape in which the tool reference point is positioned at the representative point defined on the machining surface and reversed with respect to the machining posture, and is represented in a three-dimensional grid space. To do. That is, in the transposed tool grid data, the tool shape inverted and arranged in the three-dimensional grid space is described by the unit tertiary grid group region where the tool shape exists. Transposition distance field data describes the distance between each grid point belonging to the unit 3D grid group through which the tool shape boundary passes and the tool shape boundary. The tool shape boundary position at.

Next, the tool reference plane model creation device creates merged grid data using the transposed tool grid data group created for each representative point on the machining surface. A unit three-dimensional lattice group region described by each of the transposed tool lattice data groups corresponds to a tool shape that is inverted and arranged at one representative point on the processing surface. Therefore, the region obtained by merging the unit three-dimensional lattice group region described by each of the transposed tool lattice data group corresponds to the envelope shape of the tool shape group that is inverted and arranged at each representative point on the processing surface, and the boundary of the merged region. In the unit three-dimensional lattice group located at, the envelope boundary surface of the tool shape group reversely arranged at each representative point on the processing surface passes. Since the envelope boundary surface of the tool shape group corresponds to the tool reference surface, the merged lattice data describes a unit three-dimensional lattice group through which the tool reference surface passes.
Next, the tool reference plane model creation device creates merged distance field data using the merged grid data and the transposed distance field data group created for each representative point on the machined surface. For each grid point belonging to the unit 3D grid group described by the merged grid data, the minimum value among the distance values described in the transposed distance field data group is inverted at each representative point on the processing surface. The distance value to the envelope boundary surface of a tool shape group is shown. That is, the distance value to the tool boundary surface is shown. Therefore, the tool reference plane passes by extracting the minimum value of the distance values described in the transposed distance field data group for each grid point belonging to the unit 3D grid group described in the merged grid data. The merged distance field data describing the distance value to the tool reference plane can be obtained for each lattice point belonging to the unit three-dimensional lattice group.
Finally, the tool reference plane model creation apparatus creates a tool reference plane model representing a tool reference plane arranged in a three-dimensional space using the merged distance field data. The merged distance field data describes the distance value to the tool reference plane for each grid point belonging to the unit three-dimensional grid through which the tool reference plane passes. A tool reference plane model can be created based on the distance value described for each grid point.
According to this tool reference surface model creation device, it is not necessary to use an approximate model that approximates a machining surface, a tool shape, or the like with an approximate element, and the tool reference surface model can be created with high accuracy.

In the above-described tool reference surface model creation device, the means for creating the machining surface grid data includes the nearest point on the machining surface located closest to the center of the specified unit three-dimensional grid as a representative point on the machining surface. It is preferable to determine this.
Thereby, the representative points on the processed surface can be determined more uniformly in each of the three-dimensional directions.

The technique of the present invention can also be embodied in a method of creating a tool reference surface model that processes a processed surface into a material based on processed surface data describing the processed surface. This method of creating a tool reference plane model includes a process of preparing machining surface data, a process of preparing tool shape data, a process of creating machining surface grid data, and creating transposed tool grid data and transposition distance field data. A step of creating merged grid data, a step of creating merged distance field data, and a step of creating a tool reference plane model.
According to this method for creating a tool reference surface model, it is not necessary to use an approximate model that approximates a machining surface, a tool shape, or the like with an approximate element, and the tool reference surface model can be created with high accuracy.

The present invention also provides an apparatus for creating a model of a machining surface formed on a material when a tool is moved along the tool path based on tool path data describing the path of the tool. This machined surface model creation device includes tool path data storage means, material shape data storage means, tool shape data storage means, tool path grid data creation means, material grid data and material distance field. Means for creating data, means for creating correct tool grid data and correct distance data, data for creating difference grid data, and means for creating a machined surface model are provided.
The tool path data describes a three-dimensional space in which tool paths are arranged. The material shape data describes the material shape. The tool shape data describes the tool shape with reference to the tool reference point.
The means for creating the tool path grid data divides the 3D grid in the 3D space described in the tool path data, identifies the unit 3D grid through which the tool path passes, and the tools in the unit 3D grid A representative point is determined on the path, and tool path grid data describing the identified unit three-dimensional grid in association with the determined representative point is created.
The means for creating the material grid data and the material distance field data is a unit through which the boundary of the material shape passes when the material shape described in the material shape data is arranged in the three-dimensional space that partitions the three-dimensional lattice. A material grid that describes a unit 3D lattice group area where a material shape exists by specifying a 3D lattice group and calculating the distance from each lattice point belonging to the unit 3D lattice group to the boundary of the material shape. Material distance field data that describes the data and the calculated distance value in association with the position of the grid point is created.
The means for creating the in-place tool grid data and the in-place distance field data includes a tool shape described in the tool shape data in a three-dimensional space defined by the three-dimensional grid, and a tool at a representative point on the tool path. Specify the unit 3D lattice group through which the tool shape boundary passes when the reference point is positioned and arranged in the machining posture, and from each lattice point belonging to the unit 3D lattice group to the tool shape boundary Each of the distance values of the tool, and a normal tool grid data that describes the unit three-dimensional grid group area where the tool shape exists, and a normal distance field data that describes the calculated distance value in association with the position of the grid point create.
Means for creating the difference grid data, from the unit three-dimensional lattice group region described in the material grid data, excludes the region common to the unit three-dimensional lattice group region described in the orthopedic tool grid data group, A unit three-dimensional lattice group located at the boundary of the difference unit three-dimensional lattice group region is specified, and difference lattice data describing the specified unit three-dimensional lattice group is created.
The means for creating the difference distance field data corresponds to the distance value described in the material distance field data and the in-place distance field data for each lattice point belonging to the unit 3D lattice group described in the difference lattice data. A maximum value is specified from the distance values obtained by reversing the sign of the distance value described in addition, and differential distance field data that describes the specified maximum distance value in association with the position of the grid point is created.
The means for creating a machined surface model creates a machined surface model based on the position and distance value of the grid points described in the differential distance field data.

The machine surface model creation device first divides a three-dimensional grid in a three-dimensional space in which tool paths are arranged, identifies a unit three-dimensional grid group through which the tool path passes, and within each identified unit three-dimensional grid. A representative point is determined on the processed surface. By defining a representative point for each unit three-dimensional lattice through which the tool path passes, the representative point on the tool path can be determined relatively uniformly in each of the three-dimensional directions. Thereby, a tool path extending in various directions can be handled.
Next, the machined surface model creation device creates material grid data and material distance field data. The material grid data and material distance field data express the material shape in a three-dimensional lattice space. The material lattice data describes the material shape arranged in the three-dimensional lattice space by the unit tertiary lattice group region where the material shape exists. Material distance field data describes the distance value from each lattice point belonging to the unit 3D lattice group through which the material shape boundary passes to the material shape boundary, to the inside of the unit 3D lattice through which the material shape boundary passes. Indicates the boundary position of the material shape at.
Next, the machined surface model creation device creates correct tool grid data and correct distance data. The orthopedic tool grid data and the orthopedic distance field data position the tool reference point at the representative point determined on the tool path, and express the tool shape arranged in the posture at the time of machining in the three-dimensional grid space. That is, in the normal tool lattice data, the tool shape arranged in the three-dimensional lattice space is described by the unit tertiary lattice group region where the tool shape exists. In-place distance field data describes the distance value from each grid point of the unit 3D grid through which the tool shape boundary passes to the tool shape boundary. Indicates the boundary position of the tool shape.

Next, the machined surface model creation device creates difference grid data using the material grid data and the in-place tool grid data. The unit three-dimensional lattice group region described in the material lattice data corresponds to the material shape. The unit three-dimensional lattice group region described in the in-place tool lattice data corresponds to the tool shape. Therefore, the difference unit 3D grid group area, which excludes the area common to the unit 3D grid group area described in the in-place tool grid data from the unit 3D grid group area described in the material grid data, is Corresponds to the material shape after processing. The differential grid data describes a unit 3D grid group positioned at the boundary of the unit 3D grid group region, and describes a unit 3D grid group through which a machining surface formed on the material passes.
Next, the machined surface model creation device creates the difference distance field data using the difference grid data, the material distance field data, and the in-place distance field data. For each grid point belonging to the unit 3D grid group described by the differential grid data, the distance value described by the material distance field data and the distance value obtained by inverting the sign of the distance value described by the on-set distance field data are reversed. The maximum value among them indicates the distance value to the processed surface formed on the material. Therefore, for each grid point belonging to the unit 3D grid group described in the differential grid data, the distance value described in the material distance field data and the sign of the distance value described in the in-place distance field data are reversed. For each grid point belonging to the unit 3D grid group through which the machining surface formed on the material passes, the differential distance field data describing the distance value to the machining surface is extracted. Obtainable.
Finally, the machined surface model creation device creates a machined surface model representing the machined surface formed on the material using the difference distance field data. The differential distance field data describes a distance value to the machining surface for each lattice point belonging to the unit three-dimensional lattice group through which the machining surface passes. A machined surface model representing a machined surface can be created based on the distance value described for each grid point.
According to this machined surface model creation apparatus, it is not necessary to use an approximate model obtained by approximating a tool path, a material shape, a tool shape, or the like with an approximate element or the like, and a machined surface model can be created with high accuracy.

The technology of the present invention is also embodied in a method for creating a machining surface model formed on a material when a tool is moved along the tool path based on tool path data describing the path of the tool. Is done. The machining surface model creation method includes a step of preparing tool path data, a step of preparing material shape data, a step of preparing tool shape data, a step of creating tool path grid data, The method includes a step of creating material distance field data, a step of creating correct tool grid data and correct distance field data, a step of creating difference grid data, and a step of creating a machining surface model.
According to this method of creating a machined surface model, it is not necessary to use an approximate model obtained by approximating a tool path, a material shape, a tool shape, or the like with an approximate element or the like, and a machined surface model can be created with high accuracy.

  According to the present invention, a surface model used in NC machining technology can be created with high accuracy, and machining quality of NC machining can be improved.

First, the main features of the embodiments described below are listed.
(Mode 1) The machining surface data and tool shape data are created using a three-dimensional CAD device.
(Mode 2) The grid data creation unit first places the tool shape described by the tool shape data in the space defined by the three-dimensional grid with the tool reference point at the origin and the reference posture. Tool grid data describing a unit three-dimensional grid group through which the boundary of the tool shape passes is created. Next, the grid data creation unit creates transposed tool grid data for each representative point on the machining surface using the tool grid data.

(First embodiment)
FIG. 1 shows a functional configuration of a tool reference plane model creating apparatus 10 according to the first embodiment of the present invention. The tool reference plane model creation device 10 creates a tool reference plane model that defines a tool path for machining a machining surface into a material based on machining surface data describing the machining surface. The tool reference plane model created by the tool reference plane model creation apparatus 10 can be used to create tool path data taught to a numerically controlled (NC) machine tool.
As shown in FIG. 1, the tool reference plane model creation device 10 functionally includes a data storage unit 20, a data creation unit 50, and an input / output unit 70. The tool reference plane model creation device 10 is mainly configured by using a computer device, and the data storage unit 20, the data creation unit 50, and the input / output unit 70 are configured by the hardware and software of the computer device. ing.

The data storage unit 20 includes machining surface data 22, tool shape data 24, machining surface grid data 26, tool grid data 28, transposed tool grid data 30 groups, transposition distance field data 32 groups, and merged grid data. 34, merged distance field data 36, tool reference plane data 38, and the like can be stored. The machining surface data 22 and the tool shape data 24 are taught from the outside via the input / output unit 70 and stored in the data storage unit 20. The machining surface grid data 26, the tool grid data 28, the transposed tool grid data 30, the transposition distance field data 32, the merged grid data 34, the merged distance field data 36, and the tool reference plane data 38 are a data creation unit. 50.
The data creation unit 50 includes a lattice data creation unit 52, a transposition data creation unit 54, a merged data creation unit 56, and a tool reference plane data creation unit 58. The lattice data creation unit 52 creates the processed surface lattice data 26 using the processed surface data 22. The grid data creation unit 52 creates tool grid data 28 using the tool shape data 24. The transposed data creation unit 54 creates the transposed tool grid data 30 group and the transposed distance field data 32 group using the machining surface grid data 26 and the tool grid data 28. The merged data creation unit 56 creates merged grid data 34 using the transposed tool grid data 30 group. Further, the merged data creation unit 56 creates merged distance field data 36 using the transposed distance field data 32 group and the merged grid data 34 group. The tool reference plane data creation unit 58 creates tool reference plane data 38 describing a tool reference plane model using the merged grid data 34 and merged distance field data 36.

FIG. 2 is a flowchart showing a flow of processing executed when the tool reference plane model creation apparatus 10 creates a tool reference plane model. In accordance with the flow shown in FIG. 2, the tool reference surface model creation device 10 generates tool reference surface data 38 describing a tool reference surface model based on the machining surface data 22 and the tool shape data 24 taught from the outside. A process flow to be created will be described.
In step S <b> 2, the tool reference surface model creation apparatus 10 inputs the machining surface data 22 and the tool shape data 24 via the input / output unit 70 and stores them in the data storage unit 20. The machining surface data 22 and the tool shape data 24 are created by an external three-dimensional CAD device or the like.
FIG. 3 shows an example of the machined surface 22 a described by the machined surface data 22. As illustrated in FIG. 3, the machining surface data 22 describes a machining surface 22a formed on the material 123a by a plurality of basic shapes arranged in the xyz space. As the basic shape, for example, a vertex V, a ridge line C, a surface S, or the like is used. For example, a straight line or a curved line is used for the ridge line C, and a flat surface, a cylindrical surface, a spherical surface, a free curved surface, or the like is used for the surface S. The ridge line C is described by a curve expression C (t) using a parameter t. The surface S is described by a surface expression S (u, v) using parameters u and v. An identifier ID that can identify each of the basic shapes V, C, and S describing the processed surface 22a is assigned.
The processed surface data 22 may be data that approximates and describes the processed surface 22a by a point group arranged in the xyz space or a reference plane group (STL: Stereo lithography) arranged in the xyz space. .
FIG. 4 shows an example of the tool shape 24 a described by the tool shape data 24. As illustrated in FIG. 4, the tool shape data 24 describes the boundary surface 24b of the tool shape 24a with a plurality of basic shapes (vertex V, ridge line C, surface S, etc.) arranged in the xyz space. The tool shape data 24 describes a state in which the tool shape 24a is arranged in a reference posture (here, the tool axis is parallel to the z axis) with the arrangement position of the tool reference point 24c as the origin of the xyz space. Each basic shape C, S describing the boundary surface 24b of the tool shape 24a is assigned an identifier ID that can identify each of the basic shapes C, S.
The tool shape data 22 may be described by approximating the boundary surface 24b of the tool shape 24a by a point group arranged in the xyz space or a reference plane group (STL) arranged in the xyz space.
Although FIG. 4 illustrates a ball end mill, the tool reference plane model creation apparatus 10 uses tool reference plane data 38 for other rotating tools such as a flat end mill and a radius end mill, or other non-rotating tools. It can also be created.

In step S <b> 4 of FIG. 2, the grid data creation unit 52 of the data creation unit 50 creates the machining surface grid data 26 and the tool grid data 28. The grid data creating unit 52 creates the machined surface grid data 26 using the machined surface data 22 stored in the data storage unit 20, and uses the tool shape data 24 stored in the data storage unit 20. Data 28 is created.
With reference to FIG. 5, a process in which the lattice data creation unit 52 creates the processed surface lattice data 26 will be described. As shown in FIG. 5, the grid data creation unit 52 divides a voxel (Volume cell: unit 3D) when the machining surface data 22 partitions a 3D grid in an xyz space describing the tool shape 22a. In the lattice) VXL group, the processing surface voxel VXLa through which the processing surface 22a passes is specified. Further, the lattice data creation unit 52 identifies the representative point Na and the identifier ID of the basic shape to which the representative point Na belongs on the machining surface 22a in the identified machining surface voxel VXLa. At this time, the lattice data creation unit 52 determines the closest point on the machining surface 22a located closest to the center point G of the machining surface voxel VXL as the representative point Na on the machining surface 22a. The representative point Na is not necessarily limited to the closest point on the machining surface 22a located closest to the center point g. In FIG. 5, for the sake of clarity, the size “a” of the divided voxels is shown larger than the actual size.

Next, in order to describe the voxel group region Ra with the specified processed surface voxel VXLa group as a boundary, the lattice data creation unit 52 determines whether each of the processed surface voxels VXLa is an “upper end voxel” or “lower end voxel”. Or other voxels. Each voxel row extending in the z direction at each position in the xy direction has an inner voxel row located on the inner side (the material 123a side) of the processing surface 22a and an outer side (an anti-material) of the processing surface 22a with the processing surface voxel VXLa as a boundary. And the outer voxel row located on the 123a side). Among the machining surface voxels VXLa, the machining surface voxel VXLa in which the outer voxel row is adjacent to the upper side (z-axis positive direction) is referred to as “top voxel”, and the outer voxel row is located below (z-axis negative direction). The adjacent processed surface voxels VXLa are referred to as “lower end voxels”. In other words, the processing surface voxel VXLa that becomes the “top voxel” has a voxel group region Ra corresponding to the inner side (the material 123a side) region of the processing surface 22a when viewing the voxel row extending in the z direction at each position in the xy direction. Indicates that it is located at the top. Further, the machining surface voxel VXLa which becomes the “lower end voxel” is a voxel group region Ra corresponding to the inner side (the material 123a side) region of the machining surface 22a when viewing the voxel row extending in the z direction at each position in the xy direction. It is located at the lower end. At this time, one voxel may be the “top voxel” and the “bottom voxel”.
The grid data creation unit 52 includes, for each specified processing surface voxel VXLa, a representative point (nearest point) Na on the determined processing surface 22a and a nearest basic shape to which the representative point (nearest point) Na belongs, Machining surface grid data 26 describing a flag for distinguishing between “upper end voxel” and “lower end voxel” is created. The processing surface grid data 26 is described by distinguishing whether the processing surface voxel VXLa through which the processing surface 22a passes is “top end voxel”, “bottom end voxel”, or other voxels. A voxel group region Ra corresponding to the inner side (the material 123a side) region of the surface 22a is described.

Here, an example of a procedure for the lattice data creation unit 52 to specify the machining surface voxel VXLa through which the machining surface 22a passes from the voxel VXL group partitioned in the xyz space will be described. As described above, in the machining surface data 22, the machining surface 22a is described by the basic shape group such as the vertex V, the ridge line C, and the surface S arranged in the xyz space.
First, the lattice data creation unit 52 identifies a voxel in which the vertex V is inherent. FIG. 6 shows a voxel VXL in which the vertex V is inherent. As shown in FIG. 6, the voxel VXL in which the vertex V is inherent can be uniquely identified from the position of the vertex V.
After specifying the voxel VXL group in which the vertex V is inherent, the lattice data creating unit 52 specifies the voxel group through which the ridge line C passes. Each of the ridge lines C extends from one vertex V to another vertex V. Therefore, the lattice data creation unit 52 determines whether or not the ridge line C passes through the 26 voxels VXL that are adjacent to the voxel VXL that starts from the voxel VXL in which the previously specified vertex V exists. Execute the process. FIG. 7 shows the voxel VXL through which the ridge line C passes. In order to determine whether or not the ridge line C passes through the voxel VXL, the nearest point Ca on the ridge line C located closest to the center point g of the voxel VXL is obtained, and the nearest point Ca is within the voxel VXL. What is necessary is just to determine whether it is located in. The nearest point Ca on the ridge line C with respect to the center point g of the voxel VXL is defined by a constraint that the vector connecting the center point g and the nearest point Ca and the tangent vector C ′ at the nearest point Ca are perpendicular to each other. -It can be obtained by executing an analysis operation of the Raphson method. When the lattice data creation unit 52 specifies the voxel VXL through which the ridge line C passes from among the 26 voxels VXL adjacent to the voxel VXL in which the vertex V is inherent, the lattice data creation unit 52 then 26 adjacent to the voxel VXL through which the ridge line C passes. For each voxel, a process for determining whether or not the ridgeline C passes is executed. In this way, when the voxel VXL through which the ridge line C passes is sequentially tracked, the vertex V located at the other end of the ridge line C reaches the voxel VXL. The voxel VXL through which the ridge line C passes is sequentially traced by starting from the voxel VXL in which the one vertex V is present and then sequentially tracking the voxel VXL through which the ridge line C passes until reaching the voxel VXL in which the other vertex V is present. A group can be identified without omission.

When the lattice data creation unit 52 identifies the voxel VXL group through which each ridge line C passes, the lattice data creation unit 52 identifies the voxel group through which the surface S passes. Each of the surfaces S is surrounded by a plurality of ridge lines C. Therefore, the lattice data creation unit 52 performs a process of determining whether or not the surface S passes through the 26 voxels VXL adjacent to the voxel VXL, starting from the voxel VXL through which the ridge line C passes. . FIG. 8 shows a voxel VXL through which the surface S passes. In order to determine whether or not the surface S passes through the voxel VXL, the nearest point Sa on the nearest surface S is obtained from the center point g of the voxel VXL, and the nearest point Sa is within the voxel VXL. What is necessary is just to determine whether it is located in. The nearest point Sa on the surface S with respect to the center point g of the voxel VXL is such that the vector connecting the center point g and the nearest point Sa is perpendicular to the tangential vector Su in the s direction and the tangent vector Su in the u direction at the nearest point Sa. It can be obtained by executing the analytical calculation of the Newton-Raphson method with the above as a constraint condition. Further, the nearest point Sa obtained by this calculation is adopted as the representative point Na described above.
When the lattice data creation unit 52 specifies the voxel VXL through which the surface S passes among the 26 voxels VXL adjacent to the voxel VXL through which the ridge line C passes, then the lattice data creation unit 52 next to the voxel VXL through which the surface S passes. For each voxel, the process of determining whether or not the surface S passes is executed. In this way, when the voxel VXL through which the surface S passes is sequentially tracked, the other ridge line C located at the boundary of the surface S reaches the voxel VXL through which it passes. Leakage of the voxel VXL group through which the surface S passes by sequentially tracking the voxel VXL through which the surface S passes, starting from one voxel VXL through which the ridge line C passes and reaching the voxel VXL through which the other ridge line C passes It can be specified without.

  Similarly, the grid data creation unit 52 creates tool grid data 28 using the tool shape data 24. FIG. 9 schematically shows information described by the tool grid data 28. As shown in FIG. 9, in the tool grid data 28, a tool boundary surface voxel VXLb group through which the tool boundary surface 24b passes, a representative point Nb group on the tool boundary surface 24b, an “upper end voxel”, a “lower end voxel”, and the like. Is described in association with a flag for distinguishing between. The tool boundary surface voxel VXLb with the flag “top voxel” is located at the upper end of the voxel group region Rb in which the tool shape 24a exists when the voxel row extending in the z direction is viewed at each position in the xy direction. Indicates. Further, the tool boundary surface voxel VXLb to which the flag “lower end voxel” is attached is located at the lower end of the voxel group region Rb where the tool shape 24a exists when the voxel row extending in the z direction is viewed at each position in the xy direction. Indicates to do. The tool lattice data 28 describes the voxel group region Rb where the tool shape 24a exists by attaching the above flag to the tool boundary surface voxel VXLb group.

In step S <b> 6 of FIG. 2, the transposition data creation unit 54 creates transposition tool grid data 30 for each representative point Na on the machining surface 22 a described in the machining surface grid data 26. With reference to FIG. 10, the transposition tool grid data 30 regarding one representative point Na will be described. As shown in FIG. 10, the transposed tool grid data 30 includes a tool shape 24a described in the tool shape data 24, a tool reference point 24c positioned at a representative point Na on the machining surface 22a, and a posture during machining. Describes a group of transposed tool boundary surface voxels VXLc through which the boundary surface 24b of the tool shape 24a passes. Further, the transposed tool grid data 30 describes a representative point Nc on the tool boundary surface 24b for each transposed tool boundary surface voxel VXLc. This representative point Nc can be, for example, the closest point on the tool boundary surface 24b located closest to the center point g of the displaced tool boundary surface voxel VXLc. Further, the transposed tool grid data 30 describes a flag for distinguishing “upper end voxel”, “lower end voxel” and the like for each transposed tool boundary surface voxel VXLc. The transposed tool boundary surface voxel VXLc with the flag “upper end voxel” is the upper end of the voxel group region Rc in which the transposed tool shape 24a exists when the voxel row extending in the z direction is viewed at each position in the xy direction. It is located at. Further, the transposed tool boundary surface voxel VXLc to which the flag “lower end voxel” is attached is a voxel group region Rc in which the transposed tool shape 24a exists when a voxel row extending in the z direction is viewed at each position in the xy direction. It is located at the lower end of The transposed tool grid data 30 describes the voxel group region Rc where the transposed tool shape 24a exists by attaching the above flag to the transposed tool boundary surface voxel VXLc group.
The transposed data creation unit 54 creates the transposed grid data 30 group using the tool grid data 28 created in step S4. The tool grid data 28 is grid data that describes the tool shape 24a arranged in a reference posture while positioning the tool reference point 24c at the origin of the xyz space. On the other hand, the transposed tool grid data 30 is grid data that describes a tool shape 24a that is arranged with the tool reference point 24c positioned at the representative point Na on the machining surface 22a and reversed with respect to the posture during machining. Therefore, the tool boundary surface voxel VXLb group described by the tool grid data 28 is corrected by the amount of change in the position of the tool reference point 24c and the tool posture, thereby transposing tool boundary surface voxels described in the displaced tool grid data 30. A VXLc group can be obtained. Further, by correcting the representative point Nb group on the tool boundary surface 24a described by the tool grid data 28 by the amount of change in the position of the tool reference point 24c and the tool posture, the representative point Nc described in the displaced tool grid data 30 is obtained. Groups can be obtained approximately. By creating the transposed tool grid data 30 group using the tool grid data 28, a large number of transposed tool grid data 30 groups can be created relatively easily.

  In step S8 of FIG. 2, the transposition data creation unit 54 creates transposition distance field data 32 for each of the transposition tool grid data 30 group created in step S6. The transposition distance field data 32 will be described with reference to FIG. As shown in FIG. 11, the displacement distance field data 32 includes 8 lattice points (8 vertices) belonging to the displacement tool boundary surface voxel VXLc for each displacement tool boundary surface voxel VXLc described in the displacement tool lattice data 30. The distance value indicating the distance to the transferred tool boundary surface 24b is described. Here, the distance value has a positive / negative sign, and takes a positive value when the lattice point is located outside the tool shape boundary surface 24b, and the lattice point is located inside the tool shape 24a. Takes a negative value. When the transposition data creation unit 54 calculates the distance value from each grid point to the tool boundary surface 24b, the nearest point (representative point) Nc described in the transposed tool grid data 30 and the nearest point are Analytical calculation is executed using the basic shape to which it belongs as an initial condition. Thereby, the distance value for each lattice point can be correctly derived.

  In step S10 of FIG. 2, the merged data creation unit 56 creates merged grid data 34 using the transposed tool grid data 30 group created in step S6. The merged grid data 34 will be described with reference to FIG. As shown in FIG. 12, the merged grid data 34 includes a merged area boundary voxel VXLd group located at the boundary of the merged voxel group area Rd obtained by merging the voxel group area Rc described in each of the transposed tool grid data 30 groups. It is described. The merged voxel group region Rd corresponds to a region where there is an envelope shape of the tool shape 24a group that is reversely arranged at each representative point Na on the processing surface 22a. Therefore, the merged region boundary voxel VXLd group indicates a voxel group through which the envelope boundary surface of the tool shape 24a group reversed and arranged at each representative point Na on the processing surface 22a passes. That is, it becomes a voxel group through which the tool reference plane passes. The merge data creation unit 56 performs a merge operation on the voxel group region Rc described in the transposed tool grid data 30 group, and specifies a merge region boundary voxel VXLd group located at the boundary. Merged grid data 34 is created. Each of the merged area boundary voxels VXLd corresponds to the transfer tool boundary surface voxel VXLc described in at least one transfer tool grid data 30.

  In step S12 of FIG. 2, the merged data creation unit 56 creates merged distance field data 36 using the transposed distance field data 32 group created in step S8 and the merged grid data 34 created in step S10. The merged distance field data 36 will be described with reference to FIG. As shown in FIG. 13, the merged distance field data 36 describes the distance values d0 to d7 of 8 lattice points belonging to the merged area boundary voxel VXLd for each merged area boundary voxel VXLd described in the merged grid data 34. ing. The distance value of each grid point described in the merged distance field data 36 is the minimum value among the distance values described in the transposed distance field data 32 group in association with each grid point. For each lattice point belonging to the merged area boundary voxel VXLd group, the minimum value among the distance values described in the transposed distance field data 32 group is the tool shape inverted at each representative point Na on the machining surface 22a. The distance value to the envelope boundary surface of 24a group, ie, a tool reference surface, is shown. The merge data creation unit 56 specifies the minimum value from the distance values described in the transposed distance field data 32 group for each grid point belonging to the merged area boundary voxel VXLd group described in the merged grid data 34. The merged distance field data 36 is created by using the specified minimum distance value and the position of the grid point as a pair of data.

2, the tool reference plane data creation unit 58 creates the tool reference plane data 38 using the merged grid data 34 and the merged distance field data 36. At this time, the tool reference plane data creation unit 58 uses the distance value described in the merged distance field data 36 for each merged area boundary voxel VXLd described in the merged grid data 34 and uses the merged area boundary voxel. A tool reference plane model is created in VXL. FIG. 14 is a diagram illustrating an example of a method in which the tool reference plane data creation unit 58 creates the tool reference plane model 38a in the merged area boundary voxel VXLd. As shown in FIG. 14, it is assumed that the distance values of the eight lattice points belonging to the merged region boundary voxel VXLd are d0 to d7, of which the four distance values d0 to d3 are negative values, and the other four distance values. It is assumed that d4 to d7 are positive values. In this case, the four vertices located below the merged region boundary voxel VXLd in the drawing are located on the machining surface side with respect to the tool reference surface model 38a, and the four vertices located above the drawing are the tool reference surface model 38a. It means that it is located on the side opposite to the processed surface. Since the tool reference plane model 38a crosses the side between the lattice points where the sign of the distance value is reversed, the intersections M04, M15, M26, and M37 with the tool reference plane model 38a are determined on the side. it can. Since these intersection points M04, M15, M26, and M37 are points on the tool reference plane model 38a, the tool reference plane model 38a can be determined using these intersection points M04, M15, M26, and M37. Note that the positions of the points M04, M15, M26, and M37 on each side may be determined in consideration of the magnitude of the absolute value of the distance value of the lattice points located at both ends. As shown in FIG. 15, the tool reference plane data creation unit 58 defines a tool reference plane model 38a inside all merged area boundary voxels VXLd described in the merged grid data 34, and describes the tool reference plane model 38a. Tool reference plane data 38 to be created is created.
The tool reference plane data 38 created by the above processing flow can be used to create tool path data for teaching the tool path to the NC machine tool.

(Second embodiment)
FIG. 16 shows a functional configuration of the machined surface model creation apparatus 110 according to the second embodiment of the present invention. The machined surface model creating apparatus 110 creates a model of a machined surface formed on a material by a tool moving along the tool path based on tool path data describing the tool path. The machining surface model created by the machining surface model creation device 110 can be used for the evaluation of the tool path described by the tool path data before the actual machining using the NC machine tool.
As illustrated in FIG. 16, the machined surface model creation apparatus 110 functionally includes a data storage unit 120, a data creation unit 150, and an input / output unit 170. The machined surface model creation apparatus 110 is mainly configured by using a computer device, and the data storage unit 120, the data creation unit 150, the input / output unit 170, and the like are configured by the hardware and software of the computer device. ing.

The data storage unit 120 includes tool path data 122, material shape data 123, tool shape data 24, tool path lattice data 126, material lattice data 127, tool lattice data 28, and in-place tool lattice data 130 group. In addition, the normal distance field data 132 group, the material distance field data 133, the difference grid data 134, the difference distance field data 136, the machining surface data 138, and the like can be stored. The tool shape data 24 and the tool grid data 28 in the present embodiment are the same as the tool shape data 24 and the tool grid data 28 in the first embodiment, respectively. The tool path data 122, the material shape data 123, and the tool shape data 124 are taught from the outside via the input / output unit 170 and stored in the data storage unit 120. Tool path grid data 126, material grid data 127, tool grid data 128, regular tool grid data 130 group, regular distance field data 132 group, material distance field data 133, difference grid data 134, The difference distance field data 136 and the processed surface data 138 are created by the data creation unit 150.
The data creation unit 150 includes a lattice data creation unit 52, an in-place data creation unit 154, a difference data creation unit 156, and a processed surface data creation unit 158. The grid data creation unit 52 of the present embodiment is the same as the grid data creation unit 52 of the first embodiment. The grid data creation unit 52 creates tool path grid data 126 using the tool path data 122, creates material grid data 127 using the material shape data 123, and creates tool grid data 28 using the tool shape data 24. create. The in-place data creation unit 154 creates the in-place tool grid data 130 group and the in-place distance field data 132 group using the tool path grid data 126 and the tool grid data 28. The difference data creation unit 156 creates the difference grid data 134 using the group of orthopedic tool grid data 130. Further, the difference data creation unit 156 creates the difference distance field data 136 using the regular distance field data 132 group and the difference grid data 134 group. The machined surface data creation unit 158 creates machined surface data 138 using the difference grid data 134 and the difference distance field data 136.

FIG. 17 is a flowchart showing a flow of processing executed when the machined surface model creation apparatus 110 creates a machined surface model. In accordance with the flow shown in FIG. 17, the machining surface data creation device 110 describes machining surface data that describes a machining surface model based on the tool path data 122, the material shape data 123, and the tool shape data 24 taught from the outside. The flow of processing executed when creating 138 will be described.
In step S <b> 102, the machining surface model creation apparatus 110 inputs the tool path data 122, the material shape data 123, and the tool shape data 24 via the input / output unit 170 and stores them in the data storage unit 120. The tool path data 122, the material shape data 123, and the tool shape data 24 are created by an external three-dimensional CAD device or the like.
FIG. 18 shows an example of the tool path 122 a described by the tool path data 122. As illustrated in FIG. 18, the tool path data 122 describes a tool path 122 a arranged in the xyz space. The tool path 122a is described by a plurality of basic shapes (vertex V, ridge line C). An identifier ID that can identify each of the basic shapes V and C described in the tool path 122a is assigned.
FIG. 19 shows an example of the material shape 123 a described by the material shape data 123. As illustrated in FIG. 19, the material shape data 123 includes a boundary surface (processed surface) 123 b of the material shape 123 a by a plurality of basic shapes (vertex V, ridge line C, surface S, etc.) arranged in the xyz space. It is described. An identifier ID that can identify each of the basic shapes V, C, and S describing the material boundary surface 123b is assigned.
As the tool shape data 24, for example, the tool shape data 24 describing the tool shape 24a illustrated in FIG. 4 described in the first embodiment can be used.

In step S <b> 104 of FIG. 17, the grid data creation unit 52 of the data creation unit 150 creates the tool path grid data 126, the material grid data 127, and the tool grid data 28. The grid data creation unit 52 of this embodiment creates tool path grid data 126 using the tool path data 122 and creates material grid data 127 using the material shape data 123 as in the first embodiment. The tool lattice data 28 is created using the tool shape data 24 stored in the data storage unit 120.
The tool path grid data 126 will be described with reference to FIG. As shown in FIG. 20, in the tool path grid data 126, for each tool path voxel VXLe through which the tool path 122a passes, a representative point (nearest point from the center point g) Ne on the tool path 122a and a representative point Ne. The basic shape (closest basic shape) to which the symbol belongs is described in association with each other.
The material lattice data 127 will be described with reference to FIG. As shown in FIG. 21, in the material grid data 127, for each material boundary surface voxel VXLf through which the material boundary surface 123b passes, the representative point Nf on the material boundary surface 123b, “upper end voxel”, “lower end voxel”, etc. Differentiating flags are described in association with each other. The material boundary surface voxel VXLf with the flag “top voxel” is positioned at the upper end of the voxel group region Rf in which the material shape 123a exists when the voxel row extending in the z direction is viewed at each position in the xy direction. Indicates. In addition, the material boundary surface voxel VXLf with the flag “lower end voxel” is located at the lower end of the voxel group region Rf where the material shape 123a exists when the voxel row extending in the z direction is viewed at each position in the xy direction. Indicates to do. The material grid data 127 describes the voxel group region Rf where the material shape 123a exists by attaching the above flag to the material boundary surface voxel VXLf group.

In step S <b> 106 in FIG. 17, the in-place data creation unit 154 creates in-place tool grid data 130 for each representative point Ne on the tool path 122 a described in the tool path grid data 126. With reference to FIG. 22, the in-place tool grid data 130 related to one representative point Ne will be described. As shown in FIG. 22, the in-place tool grid data 130 includes a tool shape 24 a described in the tool shape data 24, a tool reference point 24 c positioned at a representative point Ne on the tool path 122 a, and at the time of machining. A group of in-place tool boundary surface voxels VXLg through which the tool boundary surface 24b passes when arranged in a posture is described. Further, the normal tool grid data 130 describes a representative point Ng on the tool boundary surface 24b and a basic shape to which the representative point Ng belongs for each normal tool boundary surface voxel VXLg. The representative point Ng can be, for example, the closest point on the tool boundary surface 24b located closest to the center point g of the normal placement tool boundary surface voxel VXLg. Further, the normal tool grid data 130 describes a flag for distinguishing “upper end voxel”, “lower end voxel”, and the like for each normal tool boundary surface voxel VXLg. The orthopedic tool boundary surface voxel VXLg with the flag “top voxel” is the upper end of the voxel group region Rg in which the arranged tool shape 24a exists when the voxel row extending in the z direction is viewed at each position in the xy direction. It is located at. In addition, the in-place tool boundary surface voxel VXLc to which the flag “bottom voxel” is attached is a voxel group region in which the arranged tool shape 24a exists when a voxel row extending in the z direction is viewed at each position in the xy direction. It is located at the lower end of Rg. The in-place tool grid data 130 describes the voxel group region Rg where the arranged tool shape 24a exists by attaching the above flag to the transposed tool boundary surface voxel VXLg group.
The in-place data creation unit 154 creates the in-place grid data 130 group using the tool grid data 28 created in step S104. The tool grid data 28 is grid data that describes the tool shape 24a arranged in a reference posture while positioning the tool reference point 24c at the origin of the xyz space. On the other hand, the in-place tool grid data 130 is grid data that describes the tool shape 24a arranged in the posture at the time of machining while positioning the tool reference point 24c at the representative point Ne on the tool path 122a. Therefore, by changing the tool boundary surface voxel VXLb group described by the tool grid data 28 by the amount of change in the position of the tool reference point 24c and the tool posture, the displaced tool boundary surface described in the in-place tool grid data 130 is obtained. A voxel VXLg group can be obtained. In addition, the representative points Nb on the tool boundary surface 24a described by the tool grid data 28 are corrected by the amount of change in the position of the tool reference point 24c and the tool posture, thereby representing the representative points described in the in-place tool grid data 130. The Ng group can be obtained approximately. By creating the normal tool grid data 130 group using the tool grid data 28, a large number of the normal tool grid data 130 group can be generated relatively easily.

In step S108 of FIG. 17, the in-place data creation unit 154 creates in-place distance field data 132 for each of the in-place tool grid data 130 group created in step S106. The in-place distance field data 132 will be described with reference to FIG. As shown in FIG. 23, the in-place distance field data 132 includes 8 grid points (8) belonging to the in-place tool interface voxel VXLg for each in-place tool interface voxel VXLg described in the in-place tool grid data 130. The distance values d0 to d7 indicating the distance from each of the vertices) to the arranged tool boundary surface 24b are described. The distance value described by the in-place distance field data 132 takes a positive value when the lattice point is located outside the tool shape 24a with respect to the tool boundary surface 24b, and the lattice point is relative to the tool boundary surface 24b. When it is located inside the tool shape 24a, it takes a negative value.
In step S108, the in-place data creation unit 154 creates material distance field data 133 using the material grid data 127 created in step S104. The material distance field data 133 will be described with reference to FIG. As shown in FIG. 24, the material distance field data 133 is obtained from each of the eight lattice points (eight vertices) belonging to the material boundary surface voxel Nf for each material boundary surface voxel Nf described in the material lattice data 127. The distance values d0 to d7 indicating the distance to the boundary surface 123b are described. The distance value described by the material distance field data 133 takes a positive value when the lattice point is located outside the material shape 123a with respect to the material boundary surface 123b, and the lattice point is relative to the material boundary surface 123b. When it is located inside the material shape 123a, it takes a negative value.

  In step S110 of FIG. 17, the difference data creation unit 156 creates difference grid data 134 using the material grid data 127 created in step S104 and the orthopedic tool grid data 130 created in step S106. The difference grid data 134 will be described with reference to FIG. The difference grid data 134 is an area common to the voxel group area Rg (see FIG. 22) described in the normal tool grid data 130 from the voxel group area Rf (see FIG. 21) described in the material grid data 127. The difference region boundary voxel VXLh group located at the boundary of the difference voxel group region Rh is excluded. The difference voxel group region Rh expresses the material shape processed by the tool arranged at the representative point Ne on the tool path 122a. Therefore, the difference area boundary voxel VXLd group indicates a voxel group through which a machining surface formed on the material passes. The difference data creation unit 156 performs a difference process between the voxel group region Rf described in the material lattice data 127 and the voxel group region Rg described in the in-place tool lattice data 130, and the difference voxel group region Rh A difference area boundary voxel group VXLh located at the boundary is specified.

  In step S112 of FIG. 17, the difference data creation unit 156 creates the difference distance field data 136 using the regular distance field data 132 group created in step S108 and the difference grid data 134 created in step S110. . The difference distance field data 136 will be described with reference to FIG. As shown in FIG. 26, the difference distance field data 136 describes the distance values of eight grid points belonging to the difference area boundary voxel VXLh for each difference area boundary voxel VXLh described in the difference grid data 134. The distance value of each lattice point described in the differential distance field data 136 is obtained by inverting the distance value described in the material distance field data 133 and the distance value described in the in-place distance field data 132. It is the maximum value when compared with the measured distance value. For each lattice point belonging to the difference area boundary voxel VXLh group, the distance value described in the material distance field data 133 and the distance value obtained by inverting the sign of the distance value described in the in-place distance field data 132 Is a distance value to the machining surface formed on the material by the tool arranged at the representative point Ne on the tool path 122a. The difference data creation unit 156 adds the distance value described in the material distance field data 133 and the in-place distance field data 132 for each grid point belonging to the difference area boundary voxel VXLh group described in the difference grid data 134. The maximum value when comparing the distance value obtained by reversing the sign of the described distance value is specified, the specified minimum distance value and the position of the grid point are used as a pair of data, and the difference distance field data 136 is obtained. create.

In step S <b> 114 of FIG. 17, the machining surface data creation unit 158 creates machining surface data 138 describing a machining surface model using the difference grid data 134 and the difference distance field data 136. The processing surface data creation unit 158 processes each difference area boundary voxel VXLh described in the difference grid data 134 in the difference area boundary voxel VXL based on the distance value described in the difference distance field data 136. Create a surface model. The process of creating the machined surface model can be performed in the same manner as the process of creating the tool reference surface model 38a by the tool reference surface model creating apparatus 10 of the first embodiment (see FIG. 14). As illustrated in FIG. 27, the machining surface data creation unit 158 defines a machining surface model 138a for each difference area boundary voxel VXLh, and creates machining surface data 138 describing the machining surface model 138a.
The machining surface data 138 created by the above processing flow can be used for evaluation of the tool path data 122 taught to the NC machine tool.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The block diagram which shows the structure of the preparation apparatus of a tool reference plane model. The figure which shows the processing flow which the preparation apparatus of a tool reference plane model performs. The figure which shows an example of the processing surface which processing surface data describes. The figure which shows an example of the tool shape which tool shape data describes. The figure explaining processed surface lattice data. The figure which shows the voxel in which the vertex of a basic shape is inherent. The figure which shows the voxel through which the ridgeline of a basic shape passes. The figure which shows the voxel through which the surface of a basic shape passes. The figure explaining tool grid data. The figure explaining transposition tool grid data. The figure explaining transposition distance field data. The figure explaining merged grid data. The figure explaining merge distance field data. The figure which shows the tool reference plane model produced in the merged area boundary voxel. The figure which shows a tool reference plane model. The block diagram which shows the structure of the preparation apparatus of a process surface model. The figure which shows the processing flow which the preparation apparatus of a process surface model performs. The figure which shows an example of the tool path | route which tool path | route data describes. The figure which shows an example of the material shape which material shape data describes. The figure explaining tool path lattice data. The figure explaining material lattice data. FIG. 6 is a diagram for explaining normal tool grid data. FIG. 6 is a diagram for explaining normal distance field data. The figure explaining material distance field data. The figure explaining difference grid data. The figure explaining difference distance field data. The figure which shows a process surface model.

Explanation of symbols

10. ・ Tool reference plane model creation device 20 ・ Data storage unit 22 ・ Machining surface data 24 ・ ・ Tool shape data 26 ・ ・ Machining surface grid data 28 ・ ・ Tool grid data 30 ・ ・ Transposed tool grid data 32 ・-Displacement distance field data 34-Merged grid data 36-Merged distance field data 38-Tool reference plane data 50-Data creation unit 52-Grid data creation unit 54-Transpose data creation unit 56-Merged data Creation unit 58 .. Tool reference plane data creation unit 70... Input / output unit 110 .. Machining surface model creation device 120... Data storage unit 122 .. Tool path data 123. Data 127 ·· Material grid data 130 · · Placement tool grid data 132 · · Placement distance field data 134 · · Difference grid data 136 · · Difference distance field data 138 · Machined surface data 150 ... data generating unit 154 ... Sei置 data creation section 156 ... the difference data generating unit 158 ... machined surface data generation unit

Claims (5)

An apparatus for creating a tool reference surface model that determines a path of a tool for processing a processed surface into a material based on processed surface data describing the processed surface,
Storage means for processing surface data describing a three-dimensional space in which the processing surfaces are arranged;
Tool shape data storage means describing the tool shape with reference to the tool reference point;
A 3D grid is defined in the 3D space described by the machined surface data, the unit 3D grid through which the machined surface passes is specified, the representative point is determined on the machined surface in the unit 3D grid, and the specified unit Means for creating machined surface lattice data describing the three-dimensional lattice group and the determined representative point group in association with each other;
The tool shape described in the tool shape data is positioned at the representative point on the processing surface in the three-dimensional space that defines the three-dimensional lattice, and the tool reference point is reversed with respect to the posture during processing. When the tool shape boundary is placed, the unit 3D lattice group is specified and the distance value from each lattice point belonging to the unit 3D lattice group to the tool shape boundary is calculated. Transposed tool grid data describing the existing unit 3D grid group area and transposed distance field data described by associating the calculated distance value with the position of the grid point for each representative point described in the machining plane grid data The means to create
The unit 3D grid group located at the boundary of the merged unit 3D grid group area that merges the unit 3D grid group area described in each of the transposed tool grid data groups is specified, and the specified unit 3D grid group is Means for creating merged grid data to describe;
For each grid point belonging to the unit 3D grid group described in the merged grid data, the minimum value among the distance values described in the transposed distance field data group is specified, and the specified minimum distance value is set to the grid point Means for creating merged distance field data described in association with the position;
Means for creating a tool reference plane model based on the position and distance value of the grid points described in the merged distance field data;
A device for creating a tool reference plane model.   The means for creating the machining surface grid data determines a closest point on the machining surface located closest to the center of the specified unit three-dimensional lattice as a representative point on the machining surface. 1 is a tool reference plane model creation device. A method for creating a tool reference surface model that determines a path of a tool for processing a processed surface into a material based on processed surface data describing the processed surface,
A step of preparing machining surface data describing a three-dimensional space in which the machining surface is arranged;
Preparing tool shape data describing a tool shape with reference to a tool reference point;
A 3D grid is defined in the 3D space described by the machined surface data, the unit 3D grid through which the machined surface passes is specified, the representative point is determined on the machined surface in the unit 3D grid, and the specified unit Creating processed surface grid data describing the three-dimensional grid group and the determined representative point group in association with each other;
The tool shape described in the tool shape data is positioned at the representative point on the processing surface in the three-dimensional space that defines the three-dimensional lattice, and the tool reference point is reversed with respect to the posture during processing. When the tool shape boundary is placed, the unit 3D lattice group is specified and the distance value from each lattice point belonging to the unit 3D lattice group to the tool shape boundary is calculated. Transposed tool grid data describing the existing unit 3D grid group area and transposed distance field data described by associating the calculated distance value with the position of the grid point for each representative point described in the machining plane grid data And the process to create
The unit 3D grid group located at the boundary of the merged unit 3D grid group area that merges the unit 3D grid group area described in each of the transposed tool grid data groups is specified, and the specified unit 3D grid group is Creating merged grid data to describe;
For each grid point belonging to the unit 3D grid group described in the merged grid data, the minimum value among the distance values described in the transposed distance field data group is specified, and the specified minimum distance value is set to the grid point Creating merged distance field data described in association with the position;
Creating a tool reference plane model based on the position and distance value of the grid points described in the merged distance field data;
Of creating a tool reference plane model comprising: An apparatus for creating a model of a machining surface formed on a material when a tool is moved along the tool path based on tool path data describing a tool path,
Storage means for tool path data describing a three-dimensional space in which the tool path is arranged;
Means for storing material shape data describing the material shape;
Tool shape data storage means describing the tool shape with reference to the tool reference point;
A 3D grid is defined in the 3D space described in the tool path data, the unit 3D grid through which the tool path passes is specified, and the representative point is determined and specified on the tool path in the unit 3D grid. Means for creating tool path grid data describing the unit three-dimensional grid and the determined representative points in association with each other;
When the material shape described in the material shape data is arranged in the three-dimensional space that defines the three-dimensional lattice, the unit three-dimensional lattice group through which the boundary of the material shape passes is specified, and the unit three-dimensional lattice Calculate the distance value from each grid point belonging to the group to the boundary of the material shape, and correspond the material grid data describing the unit 3D lattice group area where the material shape exists and the calculated distance value to the position of the grid point A means for creating material distance field data to be described,
When the tool shape described in the tool shape data is placed in a representative point on the tool path in the three-dimensional space that defines the three-dimensional lattice, and the tool reference point is arranged in the posture at the time of machining, The unit 3D lattice group where the tool shape exists is determined by specifying the unit 3D lattice group through which the shape boundary passes and calculating the distance value from each lattice point belonging to the unit 3D lattice group to the tool shape boundary. Means for creating orthopedic tool grid data describing a group region, and orthopedic distance field data describing the calculated distance value in association with the position of the grid point;
Positioned at the boundary of the difference unit 3D lattice group area by excluding the area common to the unit 3D lattice group area described in the in-place tool lattice data from the unit 3D lattice group area described in the material lattice data Means for identifying unit 3D lattice groups to be created and creating differential lattice data describing the identified unit 3D lattice groups;
For each grid point belonging to the unit 3D grid group described in the differential grid data, the distance value described in the material distance field data and the positive / negative of the distance value described in association with the in-place distance field data Identifying a maximum value among the distance values obtained by reversing, and creating difference distance field data describing the specified maximum distance value in association with the position of the grid point;
Means for creating a machined surface model based on the position and distance value of the grid points described in the differential distance field data;
An apparatus for creating a machined surface model. A method of creating a machining surface model formed on a material when a tool is moved along the tool path based on tool path data describing a tool path,
Preparing tool path data describing a three-dimensional space in which tool paths are arranged;
Preparing material shape data describing the material shape;
Preparing tool shape data describing a tool shape with reference to a tool reference point;
A three-dimensional grid is defined in the three-dimensional space described in the tool path data, a unit three-dimensional grid through which the tool path passes is specified, and a representative point is determined on the tool path in the unit three-dimensional grid, Creating tool path grid data describing the identified unit three-dimensional grid in association with the determined representative points;
When the material shape described in the material shape data is arranged in the three-dimensional space that defines the three-dimensional lattice, the unit three-dimensional lattice group through which the boundary of the material shape passes is specified, and the unit three-dimensional lattice Calculate the distance value from each grid point belonging to the group to the boundary of the material shape, and correspond the material grid data describing the unit 3D lattice group area where the material shape exists and the calculated distance value to the position of the grid point A process of creating material distance field data to be described,
When a tool shape described in tool shape data is placed in a representative point on the tool path in a three-dimensional space that divides the three-dimensional lattice, and a tool reference point is arranged in a posture at the time of machining, The unit 3D lattice group where the tool shape exists is determined by specifying the unit 3D lattice group through which the shape boundary passes and calculating the distance value from each lattice point belonging to the unit 3D lattice group to the tool shape boundary. Creating orthopedic tool grid data describing the group area, and orthopedic distance field data describing the calculated distance value in association with the position of the grid points;
Positioned at the boundary of the difference unit 3D lattice group area by excluding the area common to the unit 3D lattice group area described in the in-place tool lattice data from the unit 3D lattice group area described in the material lattice data Identifying a unit 3D lattice group to be processed, and creating processing material lattice data describing the identified unit 3D lattice group;
For each lattice point belonging to the unit 3D lattice group described in the material lattice data, the distance value described in the material distance field data and the positive / negative of the distance value described in association with the in-place distance field data Identifying a maximum value among the distance values obtained by reversing and creating differential distance field data describing the identified maximum distance value in association with the position of the grid point;
Creating a machined surface model based on the position and distance value of the grid points described in the differential distance field data;
A method for creating a machined surface model comprising:

Images