Product design guidelines similar to branding manuals ?

Hi everyone,
I’m looking for guidelines for lines of product design, something similar to communication branding manuals used to set certain rules to apply while doing graphic communication, like ads, packaging, etc.

An example could be the line of Braun products by Dieter Rams, or something like Sony’s line of cameras that have a distinct design.
Do they depend just on the designers head or is there some sort of guides?

I come from a graphic design background so I have not enough references inside industrial design to search for them.

You’re looking for “Visual Brand Language” (VBL) guides. I haven’t really seen any official VBL guides publicly available online, unfortunately.

Also sometimes cold DLS, Design Language System. There was a thread awhile back on this and some folks found or posted examples.

Yeah, the examples were Kitchen Aid by Ziba, and 3Com by Mark Wilson (@IDEO I think). I still have those PDFs tucked away some place, although they’re probably just as easy to google.

I recently saw a nine-volume brand guidelines publication from Siemens, circa early 90’s. It was a really comprehensive and well-designed set of brochures/mini-books. Makes me think if you want to find good examples of these things - look to Germany.

Thanks all for your comments.
Now I know they do exist but are super secret documents.
I’ve found some terms like Design Language Guideline from design studios that create them for clients, but not an actual document

It’s strange that it is not taught in universities around here. I’m guessing its about scale in order to have a lineup of products to develop a guideline or system.