Years ago I found this book on Amazon. It is fascinating that it even exists. A book from 1984 on how to control your home with the Timex Sinclair 1000, the sister computer of the Sinclair ZX81.
https://archive.org/details/control-things-with-your-timex-sinclair/mode/2up
@jon
for C64 there have been interfaces for Fischertechnik with Sensors and even Roboters:
https://homecomputerguy.de/2020/12/27/fischertechnik-robotor-am-c64/