3 Design to Cost
The design to cost can be defined as a principle of action aiming the establishment of rigorous objectives. It allows compromises between performance and cost [9-10]. The "cost" constraint becomes capital and this data should be managed on the same level than technical performances. Then the cost objectives become constraints and the technical performances, variables.
The interest to integrate the cost management at the design phase is shared either by the customer and the seller since it makes it possible to control the development according to the exact needs for the future users (it incites in the search of new ideas required by the economic constraints), in addition, it makes possible to prepare and organize its production very early and to better control its margin [11].
This method of design takes again the steps of activities or tasks with a focus on the costs limits. This led to an extension of the design time due to the successive iterations needed to agree on the solutions after negotiation (technical or economic). This leads to cross the functions within the company and can be used jointly with methods of costs analysis like ABC. This also allows a very thorough analysis of the product functions linked to its costs [12].
One can however point out that the design phase is longer. But, the debugging step (pre- production) is no longer disturbed by modifications as it occurs in a traditional step. We then accept in fact "to waste" time with the design phase, therefore with the quasi-certainty to regain it downstream before the delivery date.