

Precise (+-2cm) indoor “GPS” for autonomous robots - marvelmind
http://www.marvelmind.com/

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marvelmind
Off-the-shelf indoor navigation system based on stationary ultrasonic beacons
united by radio interface in license-free band.

Location of a mobile beacon installed on a robot (cart, copter, human) is
calculated based on the propagation delay of ultrasonic signal to a set of
stationary ultrasonic beacons using trilateration.

