Nikon published this new video that gives gives an inside look of the design process of various Nikon products (unfortunately I cannot embed the video on the blog, so you have to watch it on this link).
The design team goes after the product roadmap created by the marketing team:
3D printers are used during the design process to create mockups of the new camera models:
Check also those two old videos on the history and design of the Nikon F-mount.
