Asked by: Rob Ennis, Leicester
The world’s smallest flying robot is the ‘RoboBee’ developed at the Wyss Institute, Harvard. It’s the size of your fingernail but needs to be tethered to a cable to power its wings. The smallest crawling, untethered micro-robot is only 0.2mm long. It is powered through a special floor that contains tiny electrodes. These induce an electrical charge in the robot, enabling it to move like an inchworm.
Scientists at the University of Mainz in Germany recently took the first step towards a molecular-sized nanobot, when they created a heat-powered motor using a single vibrating atom trapped in a nano-sized cone of electromagnetic radiation. Amazingly, it has the same working principles as a car engine: expanding, cooling, contracting, then heating.