The Carnegie Mellon NanoRobotics Lab uses external magnetic fields to precisely control their nanosoccer players. The micro robots are just 300×300 micron specs of neodymium-iron-boron permanent magnets that have been laser machined. The working volume is surrounded by five electromagnetic coils. Four coils are used for position while the fifth provides clamping force to the work surface. The bot can be operated almost anywhere as long as the surface isn’t magnetically active. Machine vision is used to watch the bot and provide feedback control. Embedded below is the robot moving across a glass slide next to a dime. It can travel at speeds up to 60 body lengths per second.