Another problem is how to make the motors, cameras and moving parts small enough. Some of these MAVs are using tiny motors made by RMB Miniature Bearings Inc, in Switzerland. These are some of the worlds smallest electric motors, and weigh about one third of a gram. Yes, that s a jet engine the size of a shirt button . But a bigger problem is the energy supply.
Liquid hydrocarbons come out tops.
So an MAV powered by petrol or kerosene will travel much further than one powered by batteries. Robert C. Michelson, who s the manager for Battlefield Robotics and Unmanned Vehicles at Georgia Tech Research Institute is working on a MAV with a very different power supply - a chemical muscle. But you still need electrical power to transmit your video signal back to base. And of course, the on-board computer will still need power to control the little Micro Air Vehicle as it flies around trees, up the concrete canyons of cities, or inside elevators and into buildings. They could sniff out landmines, or chemical or biological weapons.