Odometry is the use of data from moving sensors to estimate change in position over time. Odometry is used by some robots, whether they be legged or wheeled, to estimate (not determine) their position relative to a starting location. This method is sensitive to errors due to the integration of velocity measurements over time to give position estimates. Rapid and accurate data collection, equipment calibration, and processing are required in most cases for odometry to be used effectively.
The word odometry is composed from the Greek words hodos (meaning "travel", "journey") and metron (meaning "measure").
Compare to Dead reckoning.
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