Some microsatellites use the 68HC11 CPU. I hear the Voyager interstellar probes used Forth on the RCA CDP1802 processors (???
• computer_architecture.html#os has a few RTOS for robots and other real-time, small-processor environments • nanotech.html for building really, really small robots. • searching for electronic devices (Chipdir, etc.) • keyboard information, technical information on making your own devices that plug into the “keyboard socket”. • Machine Vision includes LEDs, lamps, strobes, Infrared Sensors, infrared data communication protocols, as well as RobotCams, CCD cameras, and CCD interface chips. • Scanning Tunneling Microscopes • ultrasonic sonar information, • web-connected telerobotics and digital cameras • Low-cost lasers • bps FAQ • EMI tools • schematic.html has some relevant schematics; points to the circuit diagram for “A Miniature High-Rate Speed Control with Battery Eliminator Circuit (BEC)” by Stefan Vorkoetter and the nifty Boondog links. • pc_card_faq.html very small electronic parts • “switching power supplies” DC-DC converters • clockless logic • Extremely Simple CPU Architecture