COMPUTER-ASSISTED DESIGN METHOD COMPRISING A MODELLING STEP

摘要

A computer-assisted design method for a second three-dimensional object from a first three dimensional object known only by its boundary surfaces, through a surface model of the B-Rep type, of the planar, cylindrical, cone, sphere, or toroid type, excluding free forms in defining the boundary of the object. The first object is broken down into a set of simple volume primitives. The first object is associated with a construction graph defined from these volume primitives and a set of geometric parameters for using these volume primitives in the specific case of that first object. The construction graph enables a compact description of all of the construction alternatives of the object through Boolean combinations of these primitives. The second object is generated as an alternative of the first object according to that construction graph, by modifying some of these parameters.

主权项

1. A method for a computer-assisted design of a second three-dimensional object on the basis of a first three-dimensional object known only by its boundary surfaces, via a B-Rep type volume model, of a plane, cylinder, cone, sphere, or toroid type, to the exclusion of free shapes in a definition of a boundary of the first three-dimensional object, the method comprising the steps of:
dividing the first three-dimensional object into a set of volume primitives; associating with the first three-dimensional object a construction graph defined on a basis of the volume primitives and a set of geometrical parameters for using the volume primitives in a specific case of the first three-dimensional object; and generating the second three-dimensional object as a variant of the first three-dimensional object in accordance with the construction graph by modifying some of the geometrical parameters.