LEDAS Geometry Comparison
IntroductionLEDAS Geometry Comparison (LGC) software deals with the problem of detecting differences in 3D models within a specified tolerance.
Three-D models used by industry are entities with quite a long lifecycle. They are typically modified by several designers, engineers, and technologists. Due to trends like specialization, global cooperation, and outsourcing, the number of persons working on the same model increases greatly. Today, 3D models are reused in many assemblies and derived products, making their lifecycles longer than before. This creates an urgency in controlling the modelís geometry, and checking for differences between models.
When comparing two similar-looking 3D models, it is essential to distinguish between differences that are important and defects that are negligible. So this makes 3D model comparisons very different from a simple text comparison, where only text that is fully identical is considered as having no difference. Geometrical comparison allows to detect and to visualize tiny changes that would be missed by human eye.
Tracking model modifications during its lifecycle is one scenario of LEDAS Geometry Comparison usage. Another is quality assurance of code that uses geometric computations to generate 3D models. Those who develop this kind of code are interested in automated testing of the code. As a general rule, this includes controlling the changes in the output. This control could be done by comparing the original output with the newly generated models by LEDAS Geometry Comparison.
Until now, geometry comparison has been mostly done through Boolean subtraction operations, which is a core function of geometric kernels, such as Parasolid and ACIS. The difference between 3D bodies was found by subtracting the volume of one body from another. This was a motivation for LEDAS to develop new innovative technology of geometric comparison, implemented in LEDAS Geometry Comparison