7. Conclusion

Two major revolutions have already taken place in the manufacturing industries: the widespread use of digital technology and the organization of development in project mode. Today, for most of these manufacturers, the entire product life cycle is digital: designers' sketches, CAD definitions of parts and assemblies, digital mock-ups, digital factories, digital simulation of physical phenomena and manufacturing processes, after-sales service ranges, commercial documents. As for development in project mode, it is described in frames of reference, marked out by milestones and timed. Of course, it is not set in stone, and is constantly adapting, driven by upstream design offices in some companies, and downstream manufacturing in others. But a certain number of stages remain unavoidable, which dictate the pace of development: definition of the product target, convergence between style, technology...