Interface with geometric modeling systems based on constructive geometry

In the area of CAD, especially in three-dimensional geometric modelling, the acceptance of users is a problem not yet completely solved. The handling of CAD systems represents an additional and new way to work for people with no computer training, and it brings problems for which they are not prepared. It would be good if designers with some amount of know-how and experience, but who are not predisposed to invest time with a new education process, could also work with the new tools that are the actual CAD-modelling systems. In this paper one possibility is explained to integrate the methods of constructive geometry and technical design knowlege, in the dialog with geometric modelling systems. The classes of objects that can be manipulated are specified. The author presents the work methodology and a way to describe the methods of constructive geometry, with some examples. (AGD)