The unlikely inventor of the automatic rice cooker

Unlikely? A husband and wife team, where the husband was an executive of a well-known company that made electrical appliances, and the wife cooked rice three times a day using her time-tested method which they translated into a working product together using trial and error. Sounds most likely.

How do the modern and relatively expensive (in my country at least) “fuzzy” rice cookers work?

I have always assumed the logic was very straightforward heuristics not fuzzy logic because “fuzzy” was once a buzzword applied to many things like how everything is powered by “AI” now.