I’d like to clarify that I’m an optimist, and I want us all here to make bunches of money (morally and legally), while protecting and increasing the value of our profession.
It is my strong personal opinion, developed through my professional experience and the experience of many other professional Industrial Designers, that royalties situations generally a terrible waste of your time and your effort which you should be getting paid for.
There are examples when royalties deals might be a great thing, but that is a very small percentage, when opportunity meets talent and a great team of lawyers.
You should start getting royalties when you become a VP of Design at a company you believe in and work hard towards the success of. And then they’re not royalties, they’re shares.