The Virtual Model Interlocking (VMI) concept is created to describe geometric objects and their relationships with maximum flexibility in topologic definition, geometric relations and heterogeneous information for complicated engineering processes, such as concurrent engineering, manufacturing processes, assembly analyses, and geometric reasoning. The Virtual Model Interlocking system is based on a new non-manifold modeling in Boundary Representation (B-Rep) topology, which allows detached components, partial topology or pseudo objects (Virtual Model). Each face, edge, and vertex in the topology can be interlocked to a construction plan, parameter-driven dimension, or graphic rule. These attached relationships can modify the orientation and position of the solid object, the solid topology and its dimensions by the changes propagated from other objects. VMI provides a modeling framework for engineers to describe single or groups of objects with incomplete topology during the design process. The current Solid Modeling systems are commonly used to describe 3-D objects with Boolean operations. These solid models are difficult to create and difficult to manipulate, and all the geometry entities within the solid topology cannot be accessed or manipulated directly. Virtual Model Interlocking is developed as a design and manufacturing tool to remove these restrictions.
