SparkFun GPS-RTK Dead Reckoning ZED-F9R Hookup Guide
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What is Dead Reckoning?
Dead Reckoning is the process of determining current position by combining previously determined positional data with speed and heading. This process can also be applied to determine future positions as well! The ZED-F9R uses Dead Reckoning which calculates speed and heading (amongst many other points of data) through the use of an internal inertial measurement unit (IMU). The addition of an wheel ticks, RTCM-formatted corrections, and IMU allows the ZED-F9R to produce high precision and more accurate readings in between GNSS data refreshes!
In addition, the module can also give accurate and useful GNSS data in areas where satellite connections are difficult to maintain: areas like the dense urban environments of major cities, long tunnels, parking garages, any large UFO's that may descend from the sky, etc.