A real-time interaction tool has been developed using Mixed-Reality (MR) technology, merged with a professional Computer-Aided Design (CAD) system. The built environment is a combined hardware and software add-on for a commercial CAD, which fully implements an interactive integration between real objects and mechanical or free-form surfaces, virtually modelled by engineers and designers. MR features provide the possibility to superimpose virtual models on real objects, giving to the operator the chance to recover the real component surface by quickly modelling over that, or analysing and adding virtual features to it. This approach is targeted to significantly decrease also the time required for the implementation of geometric variations in an engineering project when a physical prototype is required. In fact, all manual modifications on the real prototype need to be acquired as point clouds over the real surface model and subsequently turned in mathematical representation by a very time consuming activity, widely known as Reverse Engineering. In other terms visual overlaying allows the operator to visualize part of virtual objects correctly dimensioned and positioned with respect to the physical prototype in a real-time. All this procedure may be greatly speed-up by the introduced system, called MR-CAD. The developed software add-on enables the visualization of external world, continuously synchronizing an external webcam with an internal CAD camera view (in order to make possible the visual overlay) and provides several original and enhanced tools to model a real complex object from a single 2D image. The MR-CAD has been intensively tested in order to improve the unusual modelling approach, not only managing geometrical simple mechanical components, but also with free-form 3D surfaces. The results may be considered very interesting, due to true time reduction, especially in the physical prototype modifications.
Visual Overlay of Real and Virtual Objects in a CAD system
LIVERANI, ALFREDO;AMATI, GIANCARLO;
2005
Abstract
A real-time interaction tool has been developed using Mixed-Reality (MR) technology, merged with a professional Computer-Aided Design (CAD) system. The built environment is a combined hardware and software add-on for a commercial CAD, which fully implements an interactive integration between real objects and mechanical or free-form surfaces, virtually modelled by engineers and designers. MR features provide the possibility to superimpose virtual models on real objects, giving to the operator the chance to recover the real component surface by quickly modelling over that, or analysing and adding virtual features to it. This approach is targeted to significantly decrease also the time required for the implementation of geometric variations in an engineering project when a physical prototype is required. In fact, all manual modifications on the real prototype need to be acquired as point clouds over the real surface model and subsequently turned in mathematical representation by a very time consuming activity, widely known as Reverse Engineering. In other terms visual overlaying allows the operator to visualize part of virtual objects correctly dimensioned and positioned with respect to the physical prototype in a real-time. All this procedure may be greatly speed-up by the introduced system, called MR-CAD. The developed software add-on enables the visualization of external world, continuously synchronizing an external webcam with an internal CAD camera view (in order to make possible the visual overlay) and provides several original and enhanced tools to model a real complex object from a single 2D image. The MR-CAD has been intensively tested in order to improve the unusual modelling approach, not only managing geometrical simple mechanical components, but also with free-form 3D surfaces. The results may be considered very interesting, due to true time reduction, especially in the physical prototype modifications.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
