From need to specification: case study

The main objective of the design engineer is to obtain an exhaustive and objective definition of the customer's needs, and to build on this need with an analysis that leads to detailed planning and component implementation.

The method presented here breaks down the analysis into thirteen steps:

• brief description of the four aspects of the requirement;

• open and detailed analysis using the seven questions (How, What, Who, How much, Where, When, Why, or CQQCOQP) in a search for SMART answers;

• integration into a list of the strongest components;

• detailed description of components in CQQCOQP ;

• for each component, functional analysis in terms of main functions or objectives ;

• for each component, functional analysis in terms of constrained functions or constraints ;

• prioritization of objectives and constraints and extraction of representative project objectives and constraints ;

• drafting of the project scope memorandum ;

• project risk analysis on main objectives ;

• detailing objectives using the SMART approach and drafting the technical specification of requirements (STB) ;

• breaking down objectives and constraints into elementary tasks ;

• tree structure and drafting of OTT sheets for each elementary task using the FAST method;

• breakdown of objectives and constraints into unit components, and links with the STB and qualification procedures for each design stage, from the component to the overall system.