JP2011079105A - Method, device and program for interference check - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To rapidly process the evaluation of the distance of a space and the closest position between three-dimensional objects in addition to the evaluation of presence/absence of any interference between them. <P>SOLUTION: An interference checking device 10 includes: a space segmentation unit 11 for dividing a virtual space into meshes and segmenting it into small areas; a shortest distance map preparation unit 12 for preparing a shortest distance map to a reference body object by calculating each apex of the mesh and the shortest distance and the direction to a surface of the reference body object, and registering them as information associated with each mesh apex; a shortest distance evaluation point setting unit 13 for setting the evaluation point for evaluating the shortest distance to the reference body object on a mobile body object; and an interference checking unit 14 for acquiring the shortest distance to the reference body object by referring the shortest distance map based on the coordinate values of the shortest distance evaluation point. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an interference check method, an interference check device, and an interference check program for determining the presence or absence of a collision between three-dimensional objects defined in a virtual space.

  Determining whether or not there is a collision between three-dimensional objects defined in the virtual space is generally called interference check. In the fields of three-dimensional CAD, robot and machine operation simulation, game software, computer graphics, etc. Widely used.

  For example, robot simulation is used to confirm movement on a simulator before operating an actual robot. Robot manipulators typified by vertical articulated robots and SCARA robots need to set the operation of the robot so as not to interfere with work objects and surrounding structures. An interference check function is required for an operation called off-line teaching that determines such an operation on the simulator. In this case, not only checking for the presence or absence of interference, but also improving the offline teaching workability if information such as the shortest distance and the nearest position to an object that may interfere even if there is no interference is obtained. be able to.

  In general, a three-dimensional object in a virtual space is represented by a polygon such as a triangle. Interference checks between objects made up of polygons can be performed by determining the interference between polygons based on geometric conditions, but the calculation amount increases as the total number of polygons increases. Techniques for reducing the amount have been proposed.

  For example, a method of performing interference check by defining a sphere that includes the outer shape of an object object and comparing the radii of the spheres, and performing a detailed check by subdividing the included sphere if there is interference (see Patent Document 1). In the same way, a method of performing interference check in a spherical region and a method in which calculation efficiency is improved by decomposing a non-convex object into a convex shape (see Patent Documents 2 and 3) have been proposed. . In addition to the interference check by the sphere region, a method of evaluating in a rectangular parallelepiped region is also known, and a method of performing strict evaluation by subdividing the evaluation region is widely used.

  On the other hand, instead of performing a strict interference check between objects, a method of dividing an operation space into cells and defining a sector without an obstacle as an operable space (see Patent Document 4), or making a space into a cell There has also been proposed a method of determining that interference occurs when a flag is set on a cell in an area where a body object is subdivided and a plurality of body objects are flagged (see Patent Document 5).

JP 08-287292 A Japanese Patent No. 2915826 Japanese Patent No. 3556644 Japanese Patent Laid-Open No. 10-20916 JP 2008-305347 A

  In the above-described interference check method, it is possible to perform the check of interference between polygons with a much smaller amount of calculation than simply performing the interference check between polygons. However, in addition to checking for the presence or absence of interference, if you want to evaluate the shortest distance between objects or the nearest point, it is necessary to perform processing separately from the calculation of interference check, which increases the amount of calculation. there were.

  In addition, in order to increase the accuracy of interference check for objects with complex shapes, the number of constituent polygons must be increased to improve the representation accuracy of the 3D shape. There was a problem that the speed was reduced.

  In the robot simulation described above, when actually operating the robot, it is used as an anti-collision function that performs interference check and evaluation of the shortest distance to the obstacle in parallel and stops the robot before it interferes with the obstacle. However, in such use, it is necessary to complete the processing in a short time so that the interference check can be performed in real time.

  Therefore, the present invention has been made to solve the above-described problems, and in addition to evaluating the presence or absence of interference between three-dimensional objects, it is possible to process the evaluation of the gap distance between them and the nearest position at high speed. An object of the present invention is to provide an interference check method, an interference check device, and an interference check program.

  In order to achieve the above object, an interference check method according to the present invention is a method for checking interference between three-dimensional objects in a virtual space, and an arithmetic unit meshes the following steps, that is, a virtual space: Spatial subdivision step to divide and subdivide into small areas, calculate the shortest distance and direction from each vertex of the mesh to the surface of the reference object that is the reference object, and register it as information accompanying each mesh vertex A shortest distance map creating step for creating a shortest distance map to the reference object, and an evaluation point for evaluating the shortest distance to the reference object on the moving object moving in the virtual space A shortest distance evaluation point setting step, and a reference to the shortest distance map based on the coordinate value of the shortest distance evaluation point. To obtain the shortest distance to the reference object object by, and executes a interference checking step of assessing the presence or absence of interference between the moving body object and the reference object object.

  Further, the interference check device of the present invention is a device for checking interference between three-dimensional objects in a virtual space, the space subdivision unit for dividing the virtual space into meshes and subdividing it into small regions, and the mesh The shortest distance to create the shortest distance map to the reference object by calculating the shortest distance and direction to each vertex of the reference object and the surface of the reference object that is the reference object, and registering it as information accompanying each mesh vertex A map creation unit; a shortest distance evaluation point setting unit for setting an evaluation point for evaluating the shortest distance to the reference object object on a moving object that moves in the virtual space; and The shortest distance to the reference object is acquired by referring to the shortest distance map based on the coordinate value, and the moving object Characterized in that it comprises a interference checking unit for evaluating the presence or absence of interference between the reference physical object and.

  Furthermore, the interference check program of the present invention is an interference check program for operating an arithmetic device as a device for checking interference between three-dimensional objects in a virtual space, and the arithmetic device is configured to divide the virtual space into meshes. A spatial subdivision section that subdivides the image into small areas, and calculates the shortest distance and direction from each vertex of the mesh to the surface of the reference object that is the reference object, and registers the information as information associated with each mesh vertex. To set a shortest distance map creating unit for creating a shortest distance map to the reference object and an evaluation point for evaluating the shortest distance to the reference object on the moving object moving in the virtual space. A shortest distance evaluation point setting unit, and a reference to the shortest distance map based on the coordinate value of the shortest distance evaluation point Ri to obtain the shortest distance to the reference object object, characterized in that to operate as interference checking apparatus provided with an interference check section for evaluating the presence or absence of interference between the moving body object and the reference object object.

  According to the present invention, the evaluation of the presence or absence of interference between three-dimensional objects can be processed at high speed.

  Further, according to the present invention, the evaluation of the gap distance between the three-dimensional objects and the nearest position can be processed at high speed.

The perspective view explaining the shape of a standard object object and a moving object object. The block diagram which shows the function structure of one Embodiment of the interference check apparatus which concerns on this invention. The flowchart which shows the detailed process of one Embodiment of the interference check method which concerns on this invention. It is the shortest distance map figure used in one Embodiment of the interference check method which concerns on this invention, (a) is the shortest distance map in xy sectional drawing, (b) is a graph which shows the shortest distance in an AA position. Explanatory drawing which shows an example of the division | segmentation method of OBB, and the setting method of the shortest distance evaluation point. Explanatory drawing which shows an example of OBBTTree. FIG. 5 is a shortest distance map when a reference object is added to the shortest distance map of FIG. 4, where (a) shows the shortest distance map in the xy sectional view, and (b) shows the shortest distance at the AA position. Graph.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
A method for checking interference between two object objects constituted by triangular polygon groups will be described. One object is an immovable object such as an environmental structure, the other object is a moving object that moves around the structure, the former is a reference object, and the latter is a moving object.

  An object object having an arbitrary shape constituted by polygons can be used.

  In the present embodiment, as shown in FIG. 1, the reference object object 101 is assumed to be a cylindrical object having a height in the z-axis direction, and the moving object object 102 is assumed to be a shape assuming a robot manipulator hand.

  FIG. 2 is a block diagram showing a functional configuration of the interference check apparatus according to the present embodiment.

  In this interference check device 10, the virtual space is divided into meshes and subdivided into small areas to define mesh vertices, based on the data of each vertex of the mesh defined in the space subdivision unit 11, The shortest distance map creating unit that creates the shortest distance map to the reference object object 101 by calculating the shortest distance and direction to the surface of the reference object object 101 that is the reference object and registering it as information accompanying each mesh vertex. 12. Set by the shortest distance evaluation point setting unit 13 and the shortest distance evaluation point setting unit 13 for setting an evaluation point for evaluating the shortest distance to the reference object object 101 on the moving object object 102 moving in the virtual space. The shortest distance created in the shortest distance map creation unit 12 based on the coordinate value of the shortest distance evaluation point An interference check unit 14 that calculates the shortest distance to the reference object object 101 by referring to the top and evaluates the presence or absence of interference between the moving object object 102 and the reference object object 101 and the gap distance until the interference occurs. ing.

  Hereinafter, the detailed processing of the interference check will be described with reference to FIG.

(Space segmentation part 11)
The space segmentation unit 11 subdivides the space range where the interference check needs to be performed, that is, the space of the moving range of the moving object, into meshes and defines mesh vertices (S2011).

  The shape and size of the mesh may be determined in accordance with the required accuracy of the interference check, and are finely generated in the surface peripheral region of the reference object object, such as mesh division used in the finite element method or the like. On the other hand, in a region far from the surface, interference does not occur and a strict interference check is not required, so a coarse mesh may be set. In the following description, the xyz space is described as being mesh-divided into equidistant grids for easy understanding.

(Shortest distance map creation unit 12)
Next, in the shortest distance map creation unit 12, the shortest distance from the mesh vertex (i) created in the spatial subdivision step 2011 (or each grid point when divided into grids) to the reference object object 101 and the latest distance are displayed. A side point is calculated (S2021).

  If the mesh vertex (i) is a point inside the reference object 101, the shortest distance value is redefined as a negative value (S2022).

  Next, the shortest distance and the nearest point coordinates are registered in the mesh vertex (i) (S2023).

  The shortest distance from the mesh vertex to the object is obtained by calculating the distance from the polygon group constituting the object. Since each polygon has information on the vertex coordinates and the normal vector of the surface made by that vertex, the distance between the mesh vertex and the polygon can be obtained from geometric conditions, and the distance to all polygons is calculated. The shortest distance is determined by obtaining the minimum value. At this time, the calculation amount may be reduced by narrowing down calculation target polygons based on the polygon position information.

  Here, when the mesh vertex is located inside the reference object object 101, the shortest distance is registered as a negative value as described above. The polygon surface has front and back definitions, and when the outer surface of the object object is the front of the polygon, the angle between the normal of the target polygon surface and the shortest distance vector when calculating the shortest distance Is an acute angle, it can be determined that the mesh vertex is a point inside the reference object 101.

  Note that the information registered in the mesh vertex may be vector information that connects the shortest distance and direction, or the nearest vertex position from the mesh vertex, instead of the shortest distance and nearest neighbor point coordinates. This vector is called the shortest distance vector.

  By executing this processing for all mesh vertices (S2024), a map of the spatial distribution of the shortest distance to the reference object object 101 is created.

  FIG. 4 shows an example of a map of the spatial distribution of the shortest distance.

  In the xy cross-sectional view of FIG. 4A, the points shown in a lattice form are the mesh vertices 401, and the range represented by diagonal lines is the xy plane cross-section of the cylindrical reference object 101. A circle described concentrically according to the outer shape of the reference object object 101 indicates an equidistant position 402 from the reference object object 101. The shortest distance vector at a certain mesh vertex p (x, y) is shown in the figure as 403. Since the shortest distance value to be given to the mesh vertex inside the reference object object 101 is a negative value, the graph shown in FIG. As indicated by the line 407, the shortest distance value is the minimum value at the center position of the internal region 406 of the reference object object 101, zero at the surface position, and increases as the distance from the surface increases.

(Shortest distance evaluation point setting unit 13)
Next, the shortest distance evaluation point setting unit 13 defines an evaluation point for performing an interference check on the outer surface or outside of the moving object object 102.

  Here, OBB (Oriented Bounding Box), which is known as a well-known technique for defining the smallest rectangular parallelepiped that encompasses the outline of a three-dimensional object, and OBB is divided to increase the approximation accuracy of the outer shape of a moving object. Thus, the OBBT tree that is subdivided to form the OBB tree structure is used.

  FIG. 5 shows a method for subdividing the OBB.

  First, eight vertices of each three-dimensional OBB are set as interference check evaluation points 501 for all OBBs constituting the OBBTTree (tier 1). Next, OBB (1) of the highest hierarchy is divided to generate OBB (2) and (3) as OBB of hierarchy 2. Further, OBB (2) and (3) are respectively divided to generate OBB (4) and (5) and OBB (6) and (7) as OBBs of the hierarchy 3.

  FIG. 6 shows the tree structure of OBBTTree. The numbers shown in FIG. 6 correspond to the OBB numbers in FIG.

  Based on the above method, as shown in FIG. 5, an OBB (hierarchy n) of the moving object 102 is created (S2031), and the vertex of the OBB (hierarchy n) is defined as the shortest distance evaluation point (S2032).

  Next, it is determined whether the distance between vertices of the OBB (hierarchy n) is equal to or smaller than a threshold value (S2033). If not below the threshold, the OBB is subdivided (S2034), and the OBB (hierarchy n) of the moving object 102 is created again (S2031).

  If the moving object 102 is moved, the position of the evaluation point 501 is updated accordingly. The setting of the evaluation point is not limited to OBB, and the polygon vertex of the moving object object 102 may be used or may be set arbitrarily.

(Interference check unit 14)
Finally, the interference check unit 14 acquires the shortest distance information at the coordinates of the shortest distance evaluation point 501 by referring to the shortest distance map.

  Since the shortest distance map is registered only in discrete mesh vertex coordinates, it is obtained by interpolating mesh vertex information around the evaluation point coordinates. When the mesh is a three-dimensional lattice, it can be obtained by a known linear space interpolation method based on the shortest distance information registered at eight surrounding lattice points that take in the evaluation point coordinates.

  If the shortest distance of the evaluation points obtained in this way is a negative value, there is an interference state, and if the shortest distance is a positive value, there is a gap distance of that distance.

  That is, in FIG. 3, first, the moving object is moved (S2040), and the shortest distance evaluation point corresponding to all OBBs (all hierarchies) is moved (S2041).

  Next, the shortest distance from the reference object object 101 is evaluated for the shortest distance evaluation point corresponding to OBB (hierarchy n) (S2042), and the shortest distance from the reference object object 101 in OBB (hierarchy n) is the smallest. Is selected (S2043), and it is determined whether or not the selected OBB is the lowest layer (S2044). If it is the lowest layer, it is determined whether or not the shortest distance is a negative value at the vertex (evaluation point) of the finally evaluated OBB (S2045). If it is not the lowest layer, detailed evaluation is performed with the lower layer OBB of the selected OBB. (S2046), the process returns to step S2042, and the shortest distance from the reference object object 101 is evaluated again for the shortest distance evaluation point corresponding to the lower layer OBB.

  In step S2044, the evaluation is performed from the top of the OBB in the top layer, and when the interference state is determined among the eight vertices (evaluation points), the shortest distance (gap distance from the reference object) is set. If there is a point smaller than the threshold value, the vertex (evaluation point) having the shortest shortest distance is extracted from the eight vertices, and re-evaluation is performed with the subdivided OBB including the point. Similarly, the subdivision of the OBB and the evaluation of the shortest distance are repeated until the required accuracy is reached.

  Next, it is determined whether or not the shortest distance is a negative value at the finally evaluated OBB vertex (evaluation point) (S2045), and if it is a negative value, the moving object object 102 and the reference object object 101 are in an interference state. (S2047). On the contrary, if all the 8 vertices of OBB are positive values, it is determined as a non-interference state (S2048). As shown in FIG. The shortest distance is set as the shortest distance 405 between both object objects (S2049).

  Since an OBB smaller than the size of the polygon cannot be created, if you want to perform a more detailed interference check, you can subdivide the polygon to create a smaller OBB, or add an evaluation point 501 on the polygon as well as the OBB vertex Or just do it.

  The interference check between the reference object object 101 and the moving object object 102 can be performed by the above processing.

  In this embodiment, it is assumed that the shape of the moving object object 102 does not change. However, when the overall shape changes with movement like a robot manipulator, an OBTree is created for each link structure that is an operation unit. Then, the evaluation point 501 may be defined.

(Effect of this embodiment)
In the interference check according to the present embodiment, it is first necessary to create a shortest distance map for the reference object object 101 and to create an evaluation point by OBBTTree for the moving object object 102. However, once created, the shortest distance can be obtained only by coordinate conversion of the evaluation point 501 in accordance with the amount of movement of the moving object object 102, reference of the shortest distance map, and interpolation processing of the reference data. The calculation amount is small and the processing can be performed at high speed. Moreover, since the interference check is performed by acquiring the shortest distance, not only the presence / absence of interference but also the gap distance can be evaluated without increasing the calculation load.

  In the interference check according to the present embodiment, the interference state is determined based on the shortest distance between the object objects. Therefore, if the shortest distance between the two objects is smaller than a set threshold value, the interference state can be regarded as an interference state. Thereby, since it is possible to perform an interference check on the assumption that an arbitrary gap distance is ensured, for example, when applied to a robot simulator, it can be used for safe operation design in which the gap distance is guaranteed.

  As described above, in the interference check according to the present embodiment, the shortest distance between the mesh vertex 401 and the reference object object 101 is obtained by calculating the distance between the polygon constituting the reference object object 101 and the mesh vertex 401, and the object shape It does not depend on the process. Therefore, the present invention can be similarly applied not only to the simple cylindrical body described above as the shape of the reference object object 101 but also to an object having a complicated shape.

  In addition, since a three-dimensional shape object composed of polygons can be created by a general three-dimensional CAD, it can be applied without requiring special preprocessing.

  In the present embodiment, the reference object object 101 is described as being stationary. However, the present invention can also be applied to a moving object. In this case, the position and orientation of the shortest distance map are set in accordance with the movement amount. Update it.

[Second Embodiment]
The shortest distance map creating unit 12 described in the first embodiment creates a shortest distance map for a single reference object 101. In the present embodiment, a method of newly adding shortest distance information from another reference object to the shortest distance map created first will be described.

  First, an independent shortest distance map is created for a reference object object to be added in the same manner as the method described in the first embodiment. The shortest distance map created first is called the shortest distance map A, and the additionally created shortest distance map is called the shortest distance map B. The shortest distance information registered in each mesh vertex is compared between the original shortest distance map A and the additionally created shortest distance map B, and the smaller distance is registered as mesh vertex information of the new shortest distance map C. By performing the above process on all mesh vertices, a new combined shortest distance map C is created.

  FIG. 7 shows a shortest distance map when a reference object 701 is added to the shortest distance map of FIG.

  Thereby, for example, when the reference object object 701 having the same shape is added to the side of the space where the cylindrical reference object object 101 shown in the first embodiment is present, the reference object object from the synthesized shortest distance map, etc. The distance line 402 is as shown in FIG. At this time, the change in the shortest distance at the A-A position is as shown by a line 408 in FIG. 7B, and as indicated by the line 408, the internal area 406 of the reference object object 101 and the internal area 702 of the reference object object 701. The minimum value is at the center position, and zero at the surface position. In a space between two reference object objects, the shortest distance is the largest at a position that is equidistant from both objects.

  In the present embodiment, the mesh vertices 401 are assumed to be in a lattice shape, but when the shortest distance maps A and B have different mesh shapes, the vertex positions do not match. In this case, the mesh vertices of the shortest distance map C are defined so as to include all the mesh vertices of both maps. When the density of mesh vertices increases more than necessary, the number of vertices may be thinned according to the definition of how to cut the mesh.

  With respect to the mesh vertex position coordinates of the shortest distance map C defined in this way, the shortest distance value of both the shortest distance maps A and B is obtained by spatial interpolation processing as shown in the first embodiment, and the distance is small. Are registered in the shortest distance map C to synthesize the map.

  By using this synthesized shortest distance map, it is possible to perform the interference check of the moving object object in the same manner as in the first embodiment even in an environment where there are a plurality of reference object objects. Also, when one reference object object moves, the shortest distance map can be updated by moving the shortest distance map specific to that object and then combining it again with the other shortest distance map.

  In the present embodiment, two reference object objects are described as an example, but the same processing can be performed even when there are three or more objects.

[Third Embodiment]
In the first embodiment, the interference check is performed by the process of the interference check unit 14 every time the moving object moves.

  However, the shortest distance (gap distance) evaluated before the moving object object 102 moves is compared with the moving amount of the moving object. If the moving amount is smaller than the gap distance, it is possible that the reference object object will interfere. Absent.

  Therefore, when the above condition is satisfied, the process of the interference check unit 14 is omitted. This is necessary for the interference check when there is no risk of interference such as when the position of the reference object is far away from the moving object or when the moving speed is small relative to the gap distance. The calculation amount can be reduced and the processing speed can be increased.

  DESCRIPTION OF SYMBOLS 10 ... Interference check apparatus, 11 ... Spatial subdivision part, 12 ... Shortest distance map preparation part, 13 ... Shortest distance evaluation point setting part, 14 ... Interference check part, 101 ... Reference | standard object object, 102 ... Moving object object, 401 ... Mesh vertex, 402 ... equidistant line from reference object, 403 ... shortest distance vector seen from mesh vertex p, 404 ... re-neighbor point of moving object, 405 ... shortest distance vector, 406 ... internal region of reference object 407: shortest distance to the reference object, 408: shortest distance to the reference object, 501 ... shortest distance evaluation point, 701 ... additional reference object, 702 ... internal area of the additional reference object

Claims (15)

A method for checking interference between three-dimensional objects in a virtual space,
The computing device has each of the following steps:
A spatial subdivision step that subdivides the virtual space into smaller areas, and
The shortest distance map to the reference object object is created by calculating the shortest distance and direction from each vertex of the mesh to the surface of the reference object that is the reference object, and registering it as information associated with each mesh vertex. The shortest distance map creation step,
A shortest distance evaluation point setting step for setting an evaluation point for evaluating the shortest distance to the reference body object on the moving object that moves in the virtual space;
An interference check step for obtaining the shortest distance to the reference object by referring to the shortest distance map based on the coordinate value of the shortest distance evaluation point and evaluating the presence or absence of interference between the moving object and the reference object When,
An interference check method comprising:   The interference check method according to claim 1, wherein in the interference check step, a gap distance until further interference is evaluated.   In the interference check step, when the evaluated gap distance is smaller than the set threshold value, the arithmetic device redefines the density so that the density is increased by increasing the number of shortest distance evaluation points on the moving object object. The interference check method according to claim 1, wherein the presence or absence of interference with the reference object and the gap distance until the interference is reevaluated.   In the shortest distance map creating step, after the computing device creates the shortest distance map to the reference object, the shortest distance map is similarly created for another reference object, and the original shortest distance map is set. The interference check method according to any one of claims 1 to 3, wherein the shortest distance map is synthesized by adopting a smaller distance compared to the shortest distance.   5. The interference according to claim 1, wherein when the moving amount of the moving object is smaller than a gap distance evaluated before the movement, the arithmetic unit omits the interference check step. Method for checking. A device for checking interference between three-dimensional objects in a virtual space,
A space segmentation unit that subdivides the virtual space into smaller areas and
The shortest distance map to the reference object object is created by calculating the shortest distance and direction from each vertex of the mesh to the surface of the reference object that is the reference object, and registering it as information associated with each mesh vertex. The shortest distance map generator,
A shortest distance evaluation point setting unit for setting an evaluation point for evaluating the shortest distance to the reference object object on the moving object moving in the virtual space;
An interference check unit that obtains the shortest distance to the reference object by referring to the shortest distance map based on the coordinate value of the shortest distance evaluation point, and evaluates the presence or absence of interference between the moving object and the reference object When,
An interference check device comprising:   The interference check apparatus according to claim 6, wherein the interference check unit evaluates a gap distance until further interference occurs.   In the interference check unit, when the evaluated gap distance is smaller than a set threshold value, the number of shortest distance evaluation points on the moving object object is increased to redefine the reference object so as to increase the density. 8. The interference check apparatus according to claim 6, wherein the presence / absence of interference with the object and the gap distance until the interference are reevaluated.   In the shortest distance map creating unit, after creating the shortest distance map to the reference object, the shortest distance map is similarly created for another reference object, and the shortest distance set in the original shortest distance map The interference check apparatus according to claim 6, wherein the shortest distance map is synthesized by adopting the one having a smaller distance in comparison.   The interference check device according to claim 6, wherein the interference check unit is not used when the moving amount of the moving object is smaller than the gap distance evaluated before the movement. An interference check program for operating an arithmetic device as a device for checking interference between three-dimensional objects in a virtual space,
The computing device,
A space segmentation unit that subdivides the virtual space into smaller areas and
The shortest distance map to the reference object object is created by calculating the shortest distance and direction from each vertex of the mesh to the surface of the reference object that is the reference object, and registering it as information associated with each mesh vertex. The shortest distance map generator,
A shortest distance evaluation point setting unit for setting an evaluation point for evaluating the shortest distance to the reference object object on the moving object moving in the virtual space;
An interference check unit that obtains the shortest distance to the reference object by referring to the shortest distance map based on the coordinate value of the shortest distance evaluation point, and evaluates the presence or absence of interference between the moving object and the reference object An interference check program which is operated as an interference check device comprising:   The interference check program according to claim 11, wherein the interference check unit evaluates a gap distance until further interference occurs.   In the interference check unit, when the evaluated gap distance is smaller than a set threshold value, the number of shortest distance evaluation points on the moving object object is increased to redefine the reference object so as to increase the density. 13. The interference check program according to claim 11, wherein the presence or absence of interference with the object and the gap distance until the interference are reevaluated.   In the shortest distance map creating unit, after creating the shortest distance map to the reference object, the shortest distance map is similarly created for another reference object, and the shortest distance set in the original shortest distance map The interference check program according to any one of claims 11 to 13, wherein the shortest distance map is synthesized by adopting a smaller distance in comparison.   The interference check program according to any one of claims 11 to 14, wherein the interference check unit is not used when the moving amount of the moving object is smaller than the gap distance evaluated before the movement.