Reverse engineering: technology and applications

The term reverse engineering identifies the digitization process of a physical object, for analysis or for computed remodeling of geometric surfaces, by means of special equipment and software.
Usually the purpose of reverse engineering is to design a new object or device, having as a reference to any already existing element, of which it is very difficult or in some cases impossible to measure the exact size. It may occur because of the complexity of the form, or the difficulty of reaching the reference in question (remote elements or height).
The fields of application are unlimited: sculptural; industrial; mechanic; aviation; aerospace; auto motive; civil; architectural; medical; and many others.

The Points Cloud

Reverse engineering is developed in two main phases: the first, called the acquisition phase of the data, is based on the "binning" of the reference in contiguous points in space that describe the shape approximation. The set of points sampled by the reference takes the name of "cloud of points".
The points to be viewed with special 3D modeling programs can be linked together by means of polygons and the whole forms a "polygon mesh", known more simply mesh, which represents by approximation the starting reference. The quality of the fit is clearly determined by the density of the sampled points. The higher the density, the better the approximation of the reference mesh.
The point clouds may be obtained by contact with a probe or laser scanning of the surfaces. We have examples of utlizzo known in the medical field through instruments such as: machines for digital ultrasound; machines for magnetic resonance imaging; etc.

The transformation

The second phase, or transformation phase, consists in the reworking of the point cloud in mathematically definable surfaces. These areas, known as NURBS surfaces (Non Uniform Rational B-Splines), geometrically approximate and rationally the mesh obtained from the point cloud. The results obtained depend mainly from the initial mesh. Any "background noise", distortions or discontinuities of the cloud points can reduce the accuracy of approximation, but they can be mitigated in the data acquisition phase, with special filtering software or manually, and during processing through a subjective interpretation of the reference.
Thanks to an innovative mesh reprocessing method to NURBS surfaces, TCS offers a service of reverse engineering of excellent quality allowing the customer to decide how nearly reach the goal. In addition the system allows total freedom of reshaping a NURBS surfaces, providing the possibility of changing the geometry according to design needs.

TCS offers reverse engineering services for any type of object, from any type of mesh produced: STL; OBJ; etc.

• The accuracy of NURBS surfaces produced may be decided by the customer.
• The generated NURBS surfaces can be exported to any IGES format; STEP; etc.
• It offers advanced modeling services, for possible completion or modification of the produced surfaces.

Read this article for more datails about 3D Laser scan technology.