JP2007328758A - Design support device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly versatile design support device capable of processing at a high speed. <P>SOLUTION: When a model data reading part 10 reads two pieces of three-dimensional design data from a model data storage device 2, a surface geometric information acquiring part divides two models based on the two pieces of three-dimensional design data into surfaces. A surface comparing part 13 compares the surfaces of the two models. A nonidentical surface searching part 15 specifies the surfaces of different shapes from each other based on a comparison result of the surface comparing part 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a design support apparatus used when performing a three-dimensional design.

  In recent years, when designing a product, it is mostly designed using a computer. Among them, in particular, the use of a three-dimensional CAD (Computer Aided Design) apparatus that can significantly shorten the period from design to product shipment has become the mainstream.

  After a 3D design data is created using a 3D CAD device, if a design change occurs, the 3D design data must be changed. In such a case, the three-dimensional design data before the change (hereinafter referred to as the old design data) is changed to create new three-dimensional design data (hereinafter referred to as the new design data). In the conventional three-dimensional CAD device, since no change history information is left, it becomes impossible to specify the changed portions of the new design data and the old design data.

  In such a case, the conventional three-dimensional CAD apparatus has no method for identifying the changed portion except for performing interference check (difference calculation) between the old design data and the new design data, and it takes a long time for the interference check. It was necessary.

  The three-dimensional CAD system described in Patent Document 1 divides three-dimensional design data into a mesh shape by a plurality of areas having a fixed shape, and for each of the old three-dimensional design data and the new three-dimensional design data, an area for each area. The volume of each area in the old 3D design data is compared with the volume value of each area in the new 3D design data, and the areas with different volume values can be reshaped. Identified as a change made. In the design change location verification device described in Patent Document 2, the first three-dimensional shape represented by the first three-dimensional design data and the second three-dimensional shape represented by the second three-dimensional design data have the same density. Centroid coordinates are obtained for each small space, and the centroid coordinates obtained for the first three-dimensional shape are compared with the centroid coordinates obtained for the second three-dimensional shape. Judge that changes are included.

JP-A-11-345256 JP 2000-331047 A

  In the case of the three-dimensional CAD system and the design change location verification apparatus described in Patent Documents 1 and 2, the change location can be specified in a shorter time than when the interference check is performed.

  However, when handling complex design data that has a large overall product size and a large number of minute shape changes in the internal structure, such as liquid crystal display cabinets, it is possible to extract shape differences between old and new design data. It is necessary to reduce the mesh size to a certain extent (for example, 0.5 mm pitch). However, if an attempt is made to execute the calculation under such conditions, the calculation speed is reduced because a large memory capacity is consumed for generating the mesh. End up. In addition, the memory capacity required for mesh generation may exceed the memory capacity installed in the device. In such a case, mesh generation becomes impossible, so products that can be designed. There is a problem that the size and shape of the device are limited.

  An object of the present invention is to provide a design support apparatus capable of high-speed processing and having high versatility.

The present invention relates to a design support device that identifies a portion having a different shape by comparing the first solid based on the first three-dimensional design data and the second solid based on the second three-dimensional design data.
Dividing means for dividing the first and second solids into plane elements;
A comparing means for comparing the first three-dimensional surface element with the second three-dimensional surface element;
A design support apparatus comprising: a specific hand that identifies surface elements having different shapes based on a comparison result by the comparison unit.

  In the invention, it is preferable that the dividing unit divides the surface element into any one of a flat surface, a cylindrical surface, a conical surface, a torus surface, and a free-form surface.

  In the invention, it is preferable that the dividing unit obtains geometric information for specifying the surface element for each surface element.

  In the present invention, the dividing means obtains a passing point coordinate and a normal vector when the surface element is a plane, and when the surface element is a cylindrical surface, an axis passing point coordinate and an axis Obtain a vector and a base radius; if the surface element is a conical surface, obtain a vertex coordinate, an axis vector and an opening angle; if the surface element is a torus surface, obtain a center coordinate, an axis vector and Two radii are obtained.

  In the invention, it is preferable that the comparison unit compares the geometric information about the first three-dimensional surface element with the geometric information about the second three-dimensional surface element.

  In the present invention, the comparing means compares the geometric information for all combinations of the first three-dimensional surface element and the second three-dimensional surface element, and the geometric information completely matches. A combination is determined to be the same surface element, and a combination in which all or part of geometric information is different is determined to be a non-identical surface element.

  In the present invention, when the surface element to be compared is a free-form surface, the comparison means compares the position at the sampling point and the normal vector as geometric information.

  In the invention, it is preferable that the specifying unit specifies a surface element having no combination determined to be the same surface element as a surface element having a different shape.

  Further, the present invention is characterized in that the surface elements specified as the surface elements having different shapes in the first solid and the second solid are displayed so as to be distinguishable from other surface elements.

  Further, in the present invention, when the surface elements having no combination determined to be the same surface element are in contact with each other through an edge, the specifying means groups the surface elements in contact with each other through the edge. The surface element groups having different shapes are specified.

  In the present invention, the surface element group having the different shape in the first three-dimensional shape is in contact with the other surface via the edge, and the surface element group having the different shape in the second three-dimensional shape is in contact with the other edge. When the surface is the same surface element, the surface element group having a different shape in the first solid and the surface element group having a different shape in the second solid are specified as changed surfaces. It is characterized by.

  Further, the present invention provides a surface element of a surface element group having a different shape in the first solid specified as the changed surface and a surface element group having a different shape in the second solid, and other surfaces having different shapes. It is characterized by being displayed so as to be distinguishable from surface elements having different element groups and shapes.

  According to the present invention, the design support apparatus that compares the first solid based on the first three-dimensional design data with the second solid based on the second three-dimensional design data and identifies portions having different shapes from each other. It is. When the dividing unit divides the first and second solids into plane elements, the comparison unit compares the first three-dimensional plane element with the second solid plane element. The specifying means specifies surface elements having different shapes from each other based on the comparison result by the comparison means.

  In this way, since two solids are compared by plane elements, it is not necessary to perform conventional mesh division or small space division, and calculation of volume or centroid is also unnecessary. Can speed up the processing necessary to identify Further, since the required memory capacity is small, processing can be performed regardless of the size and shape of the solid, and versatility is enhanced.

  According to the invention, the dividing means divides the surface element into any one of a flat surface, a cylindrical surface, a conical surface, a torus surface, and a free-form surface.

  No matter how complex the shape of the solid, it is only a set of simple geometric shapes, so by dividing it into plane elements as described above, the locations where the shapes of the two solids differ regardless of the shape of the solid Can be identified.

  According to the invention, the dividing means acquires geometric information for specifying the surface element for each surface element, and the comparing means is a geometric information for the surface element of the first three-dimensional shape. The information is compared with the geometric information for the surface element of the second solid shape.

  Further, when the surface element is a plane, a passing point coordinate and a normal vector are acquired, and when the surface element is a cylindrical surface, an axis passing point coordinate, an axis vector, and a bottom surface radius are acquired, When the surface element is a conical surface, the vertex coordinates, the axis vector, and the opening angle are acquired, and when the surface element is a torus surface, the center coordinate, the axis vector, and two radii are acquired.

  Thereby, it is possible to deal with 3D design data having no information on dimensions and information on a shape creation procedure (feature) like the imported 3D design data.

  According to the invention, the comparing means compares geometric information for all combinations of the first solid surface element and the second solid surface element. A combination in which geometric information completely matches is determined to be the same surface element, and a combination in which all or part of the geometric information is different is determined to be a non-identical surface element.

  Since the comparison can be performed only by determining whether or not the two pieces of information completely match, it is possible to reduce the amount of calculation required for the comparison and increase the calculation speed.

  According to the present invention, even if the surface element to be compared is a free-form surface, the amount of calculation required for the comparison can be reduced by using the position at the sampling point and the normal vector as geometric information. High speed is possible.

  According to the invention, the specifying unit specifies a surface element having no combination determined to be the same surface element as a surface element having a different shape.

  Thereby, it is possible to easily identify the surface elements having different shapes only by referring to the comparison result of the comparison means.

  Moreover, according to this invention, the surface element specified as a surface element from which the shape in a 1st solid | solid and a 2nd solid differs is displayed so that it can distinguish from another surface element.

Thereby, the part of a shape difference can be recognized easily.
Further, according to the present invention, in the case where the surface elements having no combination determined to be the same surface element are in contact with each other through the edge, the specifying unit determines the surface element in contact with the edge through the edge. Group and identify as surface element groups with different shapes.

  Thereby, when a plurality of surface elements having different shapes are in contact with each other through the edge, they can be easily specified as one surface element group.

  Further, according to the present invention, the surface element group having a different shape in the first three-dimensional shape is in contact with another surface through the edge, and the surface element group having a different shape in the second three-dimensional shape is in contact with the edge. When the other surface is the same surface element, the surface element group having the different shape in the first solid and the surface element group having the different shape in the second solid are identified as the changed surfaces. . As a result, the surface element group having a different shape in the first three-dimensional object and the surface element group having a different shape in the second three-dimensional object can be specified as the changed surfaces.

  Further, according to the present invention, the color of the surface of the surface element group having a different shape in the first solid specified as the changed surface and the surface element group having the different shape in the second solid is changed to the other shape. Are displayed so as to be distinguishable from surfaces other than surface element groups having different shapes and surface elements having different shapes.

  Thus, even when a plurality of shape difference locations are detected, the changed surface element is displayed so as to be distinguishable from other shape difference locations. Can be recognized. In addition, for example, if the display is made identifiable by changing the color, the surface element with a color other than the color of the changed surface element of the model before change will be displayed, and it will exist before the change. However, it can be easily recognized as a surface element that has disappeared after the change. The surface element with a color other than the color of the changed surface element of the model after change will be displayed, and it can be easily recognized as a surface element that did not exist before the change but was added after the change. .

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing a configuration of a design support system 100 including a design support apparatus 1 according to an embodiment of the present invention. The design support system 100 includes a design support device 1, a model data storage device 2, and an output device 3. The design support apparatus 1 includes a model data reading unit 10, a surface geometric information acquisition unit 11, a surface geometric information storage unit 12, a surface comparison unit 13, a surface comparison result storage unit 14, a non-identical surface search unit 15, and a non-identical surface storage unit. 16 and a shape difference display generation unit 17.

  The model data storage device 2 is a device that stores three-dimensional design data created by a three-dimensional CAD system (not shown). For example, as in the data structure shown in FIG. 2, the name (file name) 21, size (file size) 22 and update date 23 of the stored 3D design data are stored in association with the 3D design data. Yes. Here, the name of the first 3D design data (new design data) that has been changed due to the design change or the like is “_2” at the end of the main file name of the second 3D design data (old design data) before the change. "Is added to the name. For example, in the example shown in Fig. 2, there are the name "Cab.prt" and the name "Cab_2.prt", where "Cab.prt" is the name of the old design data and "Cab_2.prt" is the new name. Name of design data.

  The output device 3 is realized by a display device such as a CRT (Cathode Ray Tube) or a liquid crystal display, and displays a model shape based on three-dimensional design data.

  As the model data storage device 2 and the output device 3, a storage device and a display device provided in a three-dimensional CAD system that creates three-dimensional design data can be used.

  The design support apparatus 1 performs a design support process that specifies a changed part between the old design data and the new design data and enables the specified part to be displayed.

  The model data reading unit 10 is connected to the model data storage device 2 and functions as an interface for reading the three-dimensional design data from the model data storage device 2.

  The surface geometric information acquisition unit 11 is based on the first and second three-dimensional design data acquired via the model data reading unit 10, and the first and second models (solids) are one or more surface elements. It is a dividing unit that divides a surface and acquires geometric information (hereinafter simply referred to as “geometric information”) of each of the divided surfaces. The acquired geometric information is stored in the surface geometric information storage unit 12. The surface is divided into, for example, a flat surface, a cylindrical surface, a conical surface, a torus surface, or a free-form surface.

  No matter how complex the model is, it is only a collection of simple geometric shapes, and by dividing it into surfaces, it is possible to identify the change location regardless of the shape of the model.

  Examples of surface types and geometric information will be described. 3 shows an example of a plane, FIG. 4 shows an example of a cylindrical surface, FIG. 5 shows an example of a conical surface, and FIG. 6 shows an example of a torus surface.

  As shown in FIG. 3, when the surface type is a plane, the geometric information is a passing point coordinate and a normal vector. As shown in FIG. 4, when the surface type is a cylindrical surface, the geometric information includes the axis passing point coordinates, the axis vector, and the bottom surface radius. As shown in FIG. 5, when the surface type is a conical surface, the geometric information includes vertex coordinates, an axis vector, and an opening angle. As shown in FIG. 6, when the surface type is a torus surface, the geometric information includes center coordinates, an axis vector, and two radii (small radius and large radius). As shown in FIG. 7, when the type of surface is a free-form surface, the geometric information is sampling point coordinates and normal vectors. Here, in order to uniquely identify each geometric shape originally, vertex coordinates (4 points) in the case of a plane and height in the case of a cylindrical surface and a conical surface should be stored in the surface geometric information storage unit 12. . However, the reason for not storing in the surface geometric information storage unit 12 is that it is possible to detect only the changed surface without considering the vertex coordinates (four points) and the height, which are the spread of each geometric shape, and the change is made. This is because a surface in which the size of the plane and the height of the cylindrical surface and the conical surface are changed in conjunction with the surface is not detected. For example, as shown in FIG. 8, when the model shape (a) having a hole in the rectangular parallelepiped is changed to the shape (b) in which the upper surface of the model shape (a) is moved upward, the vertex coordinates (4 points) that are spread of each geometric shape ) And the height, in the shape (b) changed from the model shape (a) having a hole in the rectangular parallelepiped as shown in FIG. 9, the side surface and the hole shape are also changed in addition to the upper surface. It will be detected as a surface. However, if the vertex coordinates (four points) and the height, which are the spread of each geometric shape, are not taken into consideration, the shape (b) changed from the model shape (a) having a rectangular parallelepiped hole as shown in FIG. Only the top surface is detected as a modified surface.

  FIG. 11 shows a data structure of plane geometric information stored in the surface geometric information storage unit 12. As shown in the figure, a name 24 for identifying each plane, a passing point coordinate 25, and a normal vector 26 are stored in association with each other. As for a surface of a type other than a plane, similarly to a plane, a name for identifying each surface and the above-described geometric information are stored in association with each other. Further, for example, each piece of geometric information and the name of the original 3D design data are stored in association with each other so that the divided surface can be identified from which 3D design data. Yes.

  The surface comparison unit 13 acquires two pieces of different three-dimensional design data among the geometric information stored in the surface geometric information storage unit 12, that is, geometric information based on the new design data and the old design data for each design data. The comparison means for performing the comparison.

  When the types of surfaces to be compared are plane, cylindrical, conical, and torus surfaces, the geometric information that represents the surface characteristics is compared, and in the case of free-form surfaces, the position and normal vector at each sampling point If they match each other, the two surfaces are determined to be the same surface, and if any one of the geometric information is different, the two surfaces are determined to be non-identical surfaces. To do.

  Since the comparison can be performed only by determining whether or not the two pieces of geometric information completely match, it is possible to reduce the amount of calculation required for the comparison and increase the calculation speed.

  Specifically, one surface is selected from the old design data and compared with all the surfaces of the new design data to determine whether each combination is the same or not. Such comparison is repeated, and comparison is made for all surfaces of the old design data.

  In the case of a free-form surface, the number of sampling points may be one or more. When the free-form surface is represented by parameters u and v as shown in FIG. 12, the sampling points are u = 0.3, v When = 0.3 is set, it is compared whether the position and normal vector at the sampling point (u = 0.3, v = 0.3) have the same value.

  As described above, since the geometric information is compared, it is possible to deal with the three-dimensional design data having no information on the dimensions and information on the shape creation procedure (feature) like the imported three-dimensional design data.

  The surface comparison result storage unit 14 stores the comparison result by the surface comparison unit 13. As the comparison result, a combination of the names of the two compared surfaces and the comparison result are stored in association with each other.

  The non-identical surface search unit 15 is a specifying unit that searches for a surface having no combination determined to be the same by referring to the comparison result stored in the surface comparison result storage unit.

  The non-identical surface storage unit 16 stores the name of the surface searched for by the non-identical surface search unit 15 in association with the name of the surface and the name of the three-dimensional design data.

  The shape difference display generation unit 17 displays the surface of the name stored in the non-identical surface storage unit 16 so as to be distinguishable from other identical surfaces. For example, the output device 3 is instructed so that only the surface is highlighted or displayed in a color different from other surfaces.

  As described above, since two models are compared by surface, there is no need to perform conventional mesh division or small space division, and calculation of volume or centroid is also unnecessary. Processing can be speeded up. In addition, since the required memory capacity is small, processing can be performed regardless of the size and shape of the model, and versatility is enhanced.

  In the following, the design support process will be described in more detail using the model shown in FIG. 13 as an example. FIG. 13A is a perspective view showing the shape of the model 30 before the change, and FIG. 13B is a perspective view showing the shape of the model 31 after the change. This model example is a plate-like member in which a through-hole penetrating in the thickness direction is provided at the center of the plane portion. The model 31 after the change has a larger hole diameter of the through-hole than the model 30 before the change. Yes.

FIG. 14 is a flowchart showing design support processing by the design support apparatus 1.
The design support apparatus 1 is connected to, for example, a three-dimensional CAD system so as to be capable of data communication, and starts a design support process by receiving a process start command from the three-dimensional CAD system. The old design data is stored in the model data storage device 2 as the file name “model.prt”, and the new design data is stored in the model data storage device 2 as the file name “model_2.prt”.

  In step S1, the model data reading unit 10 reads old design data from the model data storage device 2, and in step S2, the model data reading unit 10 reads new design data from the model data storage device 2.

  In step S3, the surface geometric information acquisition unit 11 divides the model 30 before the change into a plurality of surfaces based on the old design data, thereby generating surface geometric information and storing the generated geometric information in the surface geometric information storage. Store in unit 12.

  In step S4, the surface geometric information acquiring unit 11 generates surface geometric information by dividing the changed model 31 into a plurality of surfaces based on the new design data, and stores the generated geometric information in the surface geometric information storage. Store in unit 12.

  FIG. 15 is a schematic diagram when the model 30 before the change is divided. The plate-like member portion is divided as six planes p01 to p06, and the through-hole portion is divided as a cylindrical surface p07. The geometric information of the planes p01 to p06 is stored in the surface geometric information storage unit 12 with a data structure as shown in FIG. 16, and the geometric information of the cylindrical surface p07 is stored in the surface geometric information storage unit with a data structure as shown in FIG. 12 is stored.

  FIG. 18 is a schematic diagram when the model 31 after the change is divided. The plate-like member portion is divided as six planes q01 to q06, and the through-hole portion is divided as a cylindrical surface q07. The geometric information of the planes q01 to q06 is stored in the surface geometric information storage unit 12 in a data structure as shown in FIG. 19, and the geometric information of the cylindrical surface q07 is stored in the surface geometric information storage unit in a data structure as shown in FIG. 12 is stored.

  In step S <b> 5, the surface comparison unit 13 acquires the geometric information of the surface to be compared from the surface geometric information storage unit 12.

  In step S6, the surface comparison unit 13 compares the acquired geometric information of the surface and determines whether they are the same or not. The comparison result is stored in the surface comparison result storage unit 14.

  For example, as shown in the schematic diagram of FIG. 21, when comparing the surface of the model 30 before the change and the surface of the model 31 after the change in a brute force manner, the surface comparison unit 13 first sets the plane p01 of the model 30 before the change. Geometric information and geometric information of all the changed models 31 (planes q01 to q06 and cylindrical surface q07) are acquired. Next, the geometric information of the plane p01 is compared with the geometric information of the planes q01 to q06 and the cylindrical surface q07. If the geometric information completely matches, it is determined that they are the same, and even a part of the geometric information must match. Are determined to be non-identical. If the types of surfaces are different, it is determined that they are not identical without comparing coordinates or the like.

  In step S7, it is determined whether or not the comparison has been completed for all the surfaces. If all have been completed, the process proceeds to step S8, and if there is a surface not compared, the process returns to step S5. In step S5, the next surface of the pre-change model 30 is acquired and the surfaces are compared again.

  When all the comparisons are completed, a comparison result of the data structure as shown in FIG. 22 is obtained. For example, the plane p01 of the pre-change model 30 and the plane q01 of the post-change model 31 are the same. The cylindrical surface p07 of the model 30 and the cylindrical surface q07 of the modified model 31 have the same passing coordinates, axis vector, and height, but are different because of different radius values.

  In step S8, the non-identical surface search unit 15 searches for a surface having no surface determined to be identical based on the comparison result stored in the surface comparison result storage unit 14, and the search result is shown in FIG. Such data structure is stored in the non-identical surface storage unit 16. The surface extracted by this search is specified as the changed portion.

  Since the cylindrical surface p07 and the cylindrical surface q07 have no surface determined to be identical, the surface name and the model data file name are associated with each other and stored in the non-identical surface storage unit 16 as the changed portion.

  In step S9, the shape difference display generation unit 17 displays the corresponding surface portion in a visually identifiable manner on the output device 3 based on the search result stored in the non-identical surface storage unit 16. In response to this, an instruction is output and the process ends.

  FIG. 24 is a diagram illustrating a display example of the output device 3. In the display example, the cylindrical surfaces p07 and q07, which are the surfaces of the changed portions, that is, the inner surfaces of the through holes in the model shape are hatched, and the changed portions can be easily confirmed.

Hereinafter, another embodiment of the present invention will be described with reference to the drawings.
FIG. 25 is a block diagram showing a configuration of a design support system 101 including a design support apparatus 33 according to another embodiment of the present invention.

  The design support system 101 includes a design support device 33, a model data storage device 2, and an output device 3. The design support apparatus 1 includes a model data reading unit 10, a surface geometric information acquisition unit 11, a surface geometric information storage unit 12, a surface comparison unit 13, a surface comparison result storage unit 14, a non-identical surface search unit 15, and a non-identical surface storage unit. 16, a shape difference display generation unit 17, an identical surface storage unit 34, a surface element grouping unit 35, a surface element group storage device 36, a changed surface specifying unit 37, and a changed surface element group storage device 38.

  Model data storage device 2, output device 3, model data reading unit 10, surface geometric information acquisition unit 11, surface geometric information storage unit 12, surface comparison unit 13, surface comparison result storage unit 14, non-identical surface search unit 15 and non-identical surface search unit 15 Since the same surface storage unit 16 has the same configuration as that included in the design support system 100 shown in FIG. 1, the same reference numerals are assigned and detailed description thereof is omitted.

  The same surface storage unit 34 stores the first three-dimensional surface name and the second three-dimensional surface name in association with each other for the pair of surface elements that are the same surface element by the non-identical surface search unit 15. The surface element grouping unit 35 detects and groups the surface elements that are in contact with each other with respect to the surface elements having names stored in the non-identical surface storage unit 16. The surface element group storage device 36 stores surface element groups having different shapes grouped by the surface element grouping unit 35 (hereinafter simply referred to as surface element groups).

  The changed surface specifying unit 37 acquires the surface A in which the surface element group in the first solid stored in the surface element group storage device 36 is in contact via the edge, and stores the first surface A stored in the surface element group storage device 36. The surface B in which the surface element groups in the two solids are in contact via the edge is acquired. Further, when the surface A and the surface B are all the same surface, the surface element group in the first solid stored in the surface element group storage device 36 and the second element stored in the surface element group storage device 36 are stored. The surface element group in the three-dimensional object is specified as the changed surface.

  The changed surface element group storage device 38 stores the surface changed by the changed surface specifying unit 37 and the specified surface element group.

  The shape difference display generation unit 17 displays the surface of the name stored in the non-identical surface storage unit 16 so as to be distinguishable from other identical surfaces, and further stores the surface element group stored in the changed surface element group storage device 38. Are displayed so that they can be distinguished from the surfaces that are not stored in the same surface and change surface element group storage device 38 but are stored in the non-identical surface storage unit 16.

  In the following, the design support process will be described in more detail using the model shown in FIG. 26 as an example.

  FIG. 26A is a perspective view showing the shape of the model 40 before the change, and FIG. 26B is a perspective view showing the shape of the model 41 after the change. The model 40 before the change has a rectangular parallelepiped shape, and the model 41 after the change has a different upper end surface and lower end surface compared to the model 40 before the change. The upper end surface has a shape in which two surfaces are combined, and the lower end surface has a shape in which one corner is cut off by the surface.

FIG. 27 is a flowchart showing design support processing by the design support apparatus 33.
The design support apparatus 33 is connected to, for example, a three-dimensional CAD system so as to be able to perform data communication, and starts a design support process by receiving a process start command from the three-dimensional CAD system. The old design data is stored in the model data storage device 2 as the file name “mode2.prt”, and the new design data is stored in the model data storage device 2 as the file name “mode2_2.prt”.

  In step S11, the model data reading unit 10 reads old design data from the model data storage device 2, and in step S12, the model data reading unit 10 reads new design data from the model data storage device 2. In step S13, the surface geometric information acquisition unit 11 divides the model 40 before the change into a plurality of surfaces based on the old design data, thereby generating surface geometric information, and storing the generated geometric information in the surface geometric information storage. Store in unit 12. In step S14, the surface geometric information acquisition unit 11 generates surface geometric information by dividing the changed model 41 into a plurality of surfaces based on the new design data, and stores the generated geometric information in the surface geometric information storage. Store in unit 12.

  FIG. 28 is a schematic diagram when the model 40 before change and the model 41 after change are divided. FIG. 28A shows the model 40 before the change, and FIG. 28B shows the model 41 after the change. The model 40 before the change is divided into six planes r01 to r06. The changed model 41 is divided into eight planes t01 to t06.

  In step S <b> 15, the surface comparison unit 13 acquires the geometric information of the surface to be compared from the surface geometric information storage unit 12.

  In step S <b> 16, the surface comparison unit 13 compares the acquired geometric information of the surface and determines whether they are the same or not. The comparison result is stored in the surface comparison result storage unit 14.

  For example, when comparing the surface of the pre-change model 40 and the surface of the post-change model 41 in a brute force manner, first, the surface comparison unit 13 first calculates the geometric information of the plane r01 of the pre-change model 40 and the post-change model 41. All (plane t01 to t08) geometric information is acquired. Next, the geometric information of the plane r01 and the geometric information of the planes t01 to t08 are respectively compared. If the geometric information completely matches, it is determined that they are the same. Judge that there is. If the types of surfaces are different, it is determined that they are not identical without comparing coordinates or the like.

  In step S17, it is determined whether or not the comparison has been completed for all the surfaces. If all have been completed, the process proceeds to step S18, and if there is a surface not compared, the process returns to step S15. In step S15, the next surface of the pre-change model 40 is acquired and the surfaces are compared again.

  In step S18, the non-identical surface search unit 15 searches for a pair of surfaces determined to be the same based on the comparison result stored in the surface comparison result storage unit 14, and the search result is as shown in FIG. The same surface storage unit 34 stores the data structure.

  In step S19, the non-identical surface search unit 15 searches for a surface having no surface determined to be identical based on the comparison result stored in the surface comparison result storage unit 14, and the search result is shown in FIG. Such data structure is stored in the non-identical surface storage unit 16. The surface extracted by this search is specified as the changed portion.

  In step S <b> 20, the surfaces that are in contact via the edges are grouped with respect to the surfaces with names stored in the non-identical surface storage unit 16.

  In the example shown in FIG. 30, since the pre-change model 40 has only the surface r061 in the non-identical surface storage unit 16, a group including the plane r06 is created and stored in the surface element group storage device 36. The post-change model 41 includes three plane elements t06, t07, and t08 in the non-identical surface storage unit 16, and includes the plane t06 and the plane t07 because the plane t06 and the plane t07 are in contact via an edge. A group is created, and since the plane t08 is not touching via an edge, a group including the plane t08 is created and stored in the plane element group storage device 36. As a result, as shown in FIG. 31, the group name and the surface name included in the group are stored in the surface element group storage device 36 in a data structure associated with each other.

  In step S <b> 21, the changed surface specifying unit 37 acquires the surface A with which the face element group in the pre-change model stored in the face element group storage device 36 is in contact via an edge, and stores it in the face element group storage device 36. The surface B in which the face element group in the changed model is in contact via the edge is obtained. When the surface A and the surface B are all the same surface, the surface element group in the pre-change model stored in the surface element group storage device 36 and the surface in the post-change model stored in the surface element group storage device 36 The element group is specified as the changed surface element group and stored in the changed surface element group storage device 38. As a result, the surface element group changed in the data structure as shown in FIG. 32 is stored in the changed surface element group storage device 38.

  For example, in the pre-change model 40, the surfaces that the group Gr1-1 stored in the surface element group storage device 36 contacts via the edges are the planes r01, r02, r03, and r04. In the model 41 after change, the surfaces that the group Gr2-1 stored in the surface element group storage device 36 contacts via the edges are the planes t01, t02, t03, and t04, and the group Gr2-2 has the edges. Surfaces in contact with each other are planes t01, t02, and t08. Since the planes r01, r02, r03, r04 and the planes t01, t02, t03, t04 are the same surface by the same surface storage unit 34, the group Gr1-1 and the group Gr2-1 are changed plane element groups. Identified as That is, as shown in the schematic diagram of FIG. 33, it can be specified that the plane r06 has been changed to the planes t06 and t07.

  In step S <b> 22, the shape difference display generation unit 17 displays the surface of the name stored in the non-identical surface storage unit 16 so that it can be distinguished from other identical surfaces, and is further stored in the change surface element group storage device 38. The output device is configured to display the surfaces included in the surface element group in such a manner that they can be distinguished from the surfaces that are not stored in the same surface and the changed surface element group storage device 38 but are stored in the non-identical surface storage unit 16. An instruction is output to 3 and the process is terminated.

  For example, as shown in the display example of FIG. 34, the plane t08 is displayed in a different color from the other same surface, and the planes r06, t07, and t08 are displayed in the same color in different colors from the same surface and the plane t08. The

1 is a block diagram showing a configuration of a design support system 100 including a design support apparatus 1 according to an embodiment of the present invention. 3 is a diagram illustrating a data structure of data stored in a model data storage device 2. FIG. It is a figure which shows the geometric information of a plane. It is a figure which shows the geometric information of a cylindrical surface. It is a figure which shows the geometric information of a conical surface. It is a figure which shows the geometric information of a torus surface. It is a figure which shows the geometric information of a free-form surface. It is a figure which shows the example of a change of a model shape. It is a figure which shows the example of a change of a model shape. It is a figure which shows the example of a change of a model shape. This is a data structure of plane geometric information stored in the surface geometric information storage unit 12. It is a figure which shows the geometric information of a free-form surface. It is a figure which shows an example of the model before a change and after a change. 4 is a flowchart showing design support processing by the design support apparatus 1; It is a schematic diagram when the model 30 before a change is divided | segmented. This is a data structure of plane geometric information stored in the surface geometric information storage unit 12. This is a data structure of geometric information of a cylindrical surface stored in the surface geometric information storage unit 12. It is a schematic diagram when the model 31 after a change is divided | segmented. This is a data structure of plane geometric information stored in the surface geometric information storage unit 12. This is a data structure of geometric information of a cylindrical surface stored in the surface geometric information storage unit 12.

It is a schematic diagram which shows the comparison with the surface of the model 30 before a change, and the surface of the model 31 after a change. It is a data structure of comparison results stored in the surface comparison result storage unit 14. This is a data structure of comparison results stored in the non-identical surface storage unit 16. 6 is a diagram illustrating a display example of the output device 3. FIG. It is a block diagram which shows the structure of the design support system 101 containing the design support apparatus 33 which is one Embodiment of this invention. It is a figure which shows an example of the model before a change and after a change. 5 is a flowchart showing a design support process by the design support apparatus 33. It is a schematic diagram when the model 40 before a change and the model 41 after a change are divided | segmented. This is a data structure of the same surface information stored in the same surface storage unit 34. This is a data structure of comparison results stored in the non-identical surface storage unit 16. 3 is a data structure of surface element group information stored in the surface element group storage device 36. FIG. 3 is a data structure of surface element group information stored in the changed surface element group storage device 38. FIG. It is a schematic diagram of a surface element group specified by the changed surface specifying unit 37. 6 is a diagram illustrating a display example of the output device 3. FIG.

Explanation of symbols

1, 33 Design support device 2 Model data storage device 3 Output device 10 Model data reading unit 11 Surface geometric information acquisition unit 12 Surface geometric information storage unit 13 Surface comparison unit 14 Surface comparison result storage unit 15 Non-identical surface search unit 16 Non-identical Surface storage unit 17 Shape difference display generation unit 34 Same surface storage unit 35 Surface element grouping unit 36 Surface element group storage device 37 Changed surface identification unit 38 Changed surface element group storage device

Claims (12)

In the design support apparatus for comparing the first solid based on the first three-dimensional design data and the second solid based on the second three-dimensional design data to identify places having different shapes,
Dividing means for dividing the first and second solids into plane elements;
A comparing means for comparing the first three-dimensional surface element with the second three-dimensional surface element;
A design support apparatus comprising: a specifying unit that specifies surface elements having different shapes based on a comparison result by the comparison unit.   The design support apparatus according to claim 1, wherein the dividing unit divides the surface element into one of a plane, a cylindrical surface, a conical surface, a torus surface, and a free-form surface.   The design support apparatus according to claim 2, wherein the dividing unit acquires geometric information for specifying the surface element for each surface element.   The dividing unit obtains a passing point coordinate and a normal vector when the surface element is a plane, and calculates an axis passing point coordinate, an axis vector, and a bottom surface radius when the surface element is a cylindrical surface. When the surface element is a conical surface, the vertex coordinates, the axis vector, and the opening angle are acquired. When the surface element is a torus surface, the center coordinates, the axis vector, and the two radii are acquired. The design support apparatus according to claim 3.   5. The design according to claim 3, wherein the comparison unit compares the geometric information for the first three-dimensional surface element with the geometric information for the second three-dimensional surface element. 6. Support device.   The comparison means compares geometric information for all combinations of the first three-dimensional surface element and the second three-dimensional surface element, and a combination whose geometric information completely matches is the same surface. The design support apparatus according to claim 5, wherein the design support apparatus is determined to be an element, and a combination in which all or part of geometric information is different is determined to be a non-identical surface element.   7. The design support apparatus according to claim 5, wherein the comparison means compares the position at the sampling point and the normal vector as geometric information when the surface element to be compared is a free-form surface. .   The design support apparatus according to claim 6, wherein the specifying unit specifies surface elements having no combination determined to be the same surface element as surface elements having different shapes.   9. The design support apparatus according to claim 8, wherein the surface elements specified as the surface elements having different shapes in the first solid and the second solid are displayed so as to be distinguishable from other surface elements.   When the surface elements having no combination that are determined to be the same surface element are in contact with each other via an edge, the specifying unit groups the surface elements in contact with each other through the edges and has different shapes. The design support apparatus according to claim 8, wherein the design support apparatus is specified as an element group.   The other surface where the surface element group having a different shape in the first solid body is in contact via an edge is the same as the other surface in which the surface element group having a different shape in the second solid body is in contact via an edge. The surface element group having the different shape in the first solid and the surface element group having the different shape in the second solid are specified as changed surfaces. Item 11. A design support apparatus according to Item 10.   A surface element group having a different shape in the first solid and a surface element group having a different shape in the second solid specified in the first solid specified as the changed surface, and a surface element group having a different shape and another shape in the second solid The design support apparatus according to claim 11, wherein the design support apparatus is displayed so as to be distinguishable from different surface elements.

Images