Design decision analysis

The mastery of production techniques, the control of production systems and the optimization of costs have all been the subject of a great deal of work. But it is only in the last decade, under economic and technological pressure due mainly to the internationalization of the market, that improving performance in the design phase has become essential. It's no longer enough to cut production costs; we need to develop quality products that meet customer requirements under optimum economic conditions. The market is imposing more and more variants on products whose lifespan is constantly decreasing: time-to-market must be reduced. The constraints of the economic environment call for better expense management, and in particular for control of activities that generate costs without necessarily providing direct added value. Design must be seen as a finalized project, interacting with an environment and constantly evolving in the context of industrial performance.

Mastering design involves not only the process activities that lead to product definition, but also understanding and improving the design function's management decisions. Indeed, the design activity is punctuated by countless decisions of all kinds, with diverse implications and relative importance... Decisions have long been a field of study, leading to a number of theories. However, decision making in the field of product design is rarely the subject of such research.

Design decisions are made "naturally" during the course of a project. Generally speaking, the decision is based on the know-how and experience of the person in charge of the project. However, it is not always easy for the various players involved to realize that a local decision (or non-decision) can subsequently have a major influence. This skill will be better shared and acquired more quickly if it is possible to refer to a structured approach to design decisions. The study of these decisions is the subject of this article, and should enable design actors to implement a performance improvement approach to product engineering. Decisions can be classified into two categories: technological decisions and driving decisions. Technological decisions correspond to choices and selections of alternatives. They are essentially procedural, and numerous methods and tools are available to support them. Management decisions concern the planning of activities and the management of knowledge evolution. They are the result of a human activity based on compromise (divergence of actors' objectives) and experience (actors' know-how). We are going to show how it is possible to understand the environment of this type of decision, in order to provide the decision-maker (individual or group) with the elements on which to base his or her decision. To do this, we need...