Enabling diagnostics in user interfaces for CAD applications

Abstract

Computer aided design (CAD) applications such as Autodesk Civil 3D allow the user to specify design constraints for a number of common geometries. These applications typically prompt the user for the required constraints and then attempt to find a feasible solution. When there is no feasible solution, however, there is little or no explanation given to the user. Furthermore, given the number of degrees of freedom, it is unreasonable to expect the user to be able to analyze the solution space of the problem in order to correct his input. In this thesis I describe an extension to the geometric solvers in Civil 3D that will enable new user interfaces to assist the user in correcting his input. Furthermore I present several example user interfaces that demonstrate these new capabilities.