Method and equipment for defining supporting structure for three-dimensional object to be made through stereolithography

Abstract

The invention is a computer-implemented method for defining a supporting structure (2) for a three-dimensional object (1) to be produced through a stereolithography process. The method comprises the following operations: defining a first surface (3) to be supported of the three-dimensional object (1) and a second surface (4) facing the first surface (3); defining elongated supporting elements (5) between the surfaces (3, 4); defining pairs of supporting elements (5); for each pair of supporting elements (5), defining an elongated reinforcing element (6) connecting the two supporting elements (5) of the pair. The definition of the pairs of supporting elements (5) comprises the following operations: defining a reference point (7) of each supporting element (5); defining a connected acyclic graph (8) having as vertices the reference points (7); for each edge (9) of the graph, defining one pair of supporting elements comprising the two supporting elements (5) corresponding to the ends of the edge (9). The definition of the pairs of supporting elements (5) comprises the further operation of defining an additional pair of supporting elements for each vertex having order 1 of the connected acyclic graph (8), the additional pair comprising a first supporting element (5) corresponding to the vertex having order 1 and a second supporting element (5) not connected to the first supporting element (5) through any edge (9).

Description

technical field [0001] The invention relates to a method for defining a support structure for a three-dimensional object to be produced by stereolithography and an apparatus for defining the support structure. Background technique [0002] As is well known, the process of stereolithography consists in producing three-dimensional objects by successively superimposing layers of the object itself. [0003] Each layer of the object is obtained by the curing of a material in liquid or pasty state, which takes place by selective exposure to light radiation. [0004] Typically, this material is a plastic-based compound that polymerizes when irradiated by said optical radiation. [0005] Each subsequent layer of the object is cured while in contact with the previous cured layer, which serves as a support for the subsequent layer. [0006] The process is controlled by a computer which is supplied with a first set of data representing the three-dimensional geometry of the object to ...

AI Technical Summary

Problems solved by technology

[0018] The known method has the disadvantage that it does not allow the support structure to be defined in an optimal manner

[0020] An undersized support structure has the disadvantage that the total volume of the undersized support structure is insufficient to properly provide the function of supporting a three-dimensional object

[0021] Conversely, an oversized support structure has an oversized overall volume

[0022] Since the time required for the stereolithography process increases proportionally to the volume to be cured, an oversized support structure has a negative impact on the overall time required to produce a three-dimensional object

[0023] Furthermore, the larger the volume of the support structure, the greater the amount of material necessary to produce the support structure, with the inconvenience of increasing the overall cost of the three-dimensional object

[0024] An overly large support structure can also be caused by an overly thick mesh, with another inconvenience that prevents cleaning operations on three-dimensional objects at the end of the stereolithography process

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