Automatic process generation: the surround problem

Automatic process generation (APG) is presented as part of a parametric approach to engineering design and manufacture. A prototype system consisting of a parametric geometric part-design system, a robust automated solid modeler, and an APG system has been built. Together these components enable an engineer to design a part parametrically, and to specify a minimal set of process parameters; the part is manufactured automatically on a five axis NC machine. This approach can shorten lead times, lower development costs, and allow time for more design iterations. The parametric approach to design and manufacture depends on the robust and fully automated nature of both the solid modeler and the APG system. Several analytical geometry problems that arise in APG can be expressed in terms of the surround algorithm problem, which is presented together with a solution