Global vision robots, by far the most common variety, use an overhead camera and off-field PC to identify and track the robots as they move around the field. The overhead camera is attached to a camera bar located 4m above the playing surface. Local vision robots have their sensing on the robot itself. The vision information is either processed on-board the robot or is transmitted back to the off-field PC for processing.
An off-field PC is used to communicate referee commands and, in the case of overhead vision, position information to the robots. Typically the off-field PC also performs most, if not all, of the processing required for coordination and control of the robots. Communication is wireless and typically uses dedicated commercial FM transmitter/receiver units.
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