Reconstruction of geometrical shapes, least squares method
In 3DReshaper®, methods are available to compute canonic shapes or registration moving matrix, but generally these mathematical "exact" ways are disappointing for many reasons:
- Point clouds are oversampled collection of points, then it is difficult to know which point should be chosen to make computation. Often more than 100000 points are candidates and choosing right points is very difficult.
- Points coming from measurement are rarely exact. A measurement error exists and the goal is to manage this error carefully.
Inside 3DReshaper® the word "best" means the possibility to handle a great number of points, finding the "best" solution of your problem in the least squares sense and to answer questions like:
- What is the best sphere, plane, registration etc. with this set of 100000 points?
- What is the max or average error?
- Could I obtain a better solution rejecting 10% or 20% of the points? but, which point to keep or to reject?
The computation is immediate, just clicking the preview button.
These high level algorithms increase dramatically the point clouds processing speed and the model accuracy.
These geometrical shapes (plane, cylinder, circle, sphere,...) can be sued in different ways:
- To export inside your CAD system using IGES and DXF interfaces so that you can make CAD models. These shapes can be used in association with sections;
- To make geometrical constructions: projections and intersections;
- To make some measurement (and reports): distance between two holes, or two planes, flatness of a plane,...
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The extract shape feature let you extract a plane with a simple click. You just need to adjust the tolerance.
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A simple click on cloud to extract plane, cylinder, boundaries or holes. You directly see distribution and average error. |
Computing best sphere. The user can adjust the tolerance to reject worst points and to obtain the most accurate result (rejected points are highlighted on the picture).
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