Formal approach to design specifications

In this paper a methodology for the specification stage in conceptual design is presented. It allows for problem solving in an active interaction with the designer. An important part of the proposed methodology is the requiremental and functional tree representing the overall logic and structure of the design problem. The specification stage aims at providing requirements and transforming them into functions of the designed object. It occurs at the highest level of abstraction and it must provide enough information to begin the synthesis process where functions are transformed into design components that are further synthesized into the designed object. The proposed approach was motivated by the following problems: specification of requirements, specification of functions, incorporation of logic into functional and requiremental trees, representation of requirements-functions interaction, and optimization in the functional space. The methodology presented is illustrated with examples.