Integration of the control electronics for a mm3-sized autonomous microrobot into a single chip

Microrobots were proposed more than 20 years ago but it has proven challenging to integrate a power system and actuators into some few mm³. There have been some attempts to create an autonomous mobile microrobot but any has been successful. Moreover, the proposed microrobots were simply mobile platforms incapable of sensing its environment and taking decisions. I-SWARM has been designed to be a real autonomous microrobot. It is powered by solar cells and provided with a locomotion unit for moving, an IR module for communicating and a contact tip for detecting near objects. Those modules are managed by an ASIC designed specifically for I-SWARM. All the electronics (power electronics, buffers, ADCs, DACs, control unit, analog transducers and an oscillator) have been embedded in the ASIC due to the limited area, 3 times 3 mm². The ASIC is a complete system on chip (SoC) that has several features not reported before in any circuit for microrobots: communicate and act cooperatively with other I-SWARM microrobots, detect near objects, measure distance to an object, light trailing and reprogramability. This paper gives some guidelines to design integrated circuits for microrobots.