SYNOPSIS

In this paper we introduce a new approach to the conceptual design of flexures and compliant mechanisms that draws upon the constraint-based design (CBD) principles of complimentary patterns and principles from projective geometry. We use projective geometric primitives to create generalized sets of 3D geometries (volumes, surfaces and lines) that represent either (1) a flexure mechanism’s degrees-of-freedom or (2) the possible flexure constraints that result in these degrees of freedom. These shapes are intuitive for a designer to understand and the shapes may be represented mathematically. As such, this approach provides the necessary elements for a computer (mathematics) and a designer (shapes and visualization) to cooperate during design. The final result of the work is to provide a set of topological shapes that represent the freedoms and constraints of parallel flexure systems. These freedom and constraint topologies (FACT) provide the foundation for creating software-based design tools for precision flexures. The explanation of FACT is somewhat abstract; therefore some hardware-focused designers may find that a bit of patience is required before the utility becomes apparent to precision engineering applications. This paper ends with a section discussing the practical utility of the abstract concepts