]Formalizing effect for functional design based on Fusion and Z

Functional design is a process in engineering design that impacts the key features of the design result. Few computational tools exist to assist designers during the functional design, and functional design success is often heavily weighted on personal experience and innate ability. This paper proposes an automated functional design approach which is supported by formalization effect in TRIZ. The standardized sets of functions and flows are intended to comprehensively describe the design space. The function types derived from the relation between input and output flows identify the external behavior. Effects can fulfill transition from inputs to output, and the happening of sub-behaviors depends upon effects. By integrating the Z formal specification style with the semi-formal object-oriented Fusion method, the effect and effect modes are formalized to facilitate rigorous reasoning about behavior and the creation of concise models. Based on six effect modes and three link methods, multiple effect chains can be generated to achieve the external behavior. The structure is confirmed by mapping between effects and examples based on the analysis of patents. An engineering example of air exhaust valve in car is presented to demonstrate the proposed functional design methodology.