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8018478/YWL5/2018-06| SICK
O P E R A T I N G I N S T R U C T I O N S | NAV245
Subject to change without notice
3
PRODUCT DESCRIPTION
3.8.4
Relative positioning system and absolute positioning system
The automated guided vehicle uses two positioning systems for lane control – a relative
positioning system and an absolute positioning system.
The relative positioning system obtains its data from the odometry (incremental encoder).
The odometry provides new data with a high update rate. The vehicle computer can calcu-
late the position of the vehicle from this data. However, the relative position calculation is
prone to errors. The error develops as more and more distance is covered.
The NAV245 positioning sensor provides relative landmark coordinates (reflectors). Using
these relative landmark coordinates, the vehicle computer can determine the automated
guided vehicle's position with its own algorithms and minimize errors from the odometry.
Fig. “Integrating the NAV245 into a navigation system”
shows a diagram explaining how the
NAV245 is integrated into a complete navigation system:
Fig. 21: Integrating the NAV245 into a navigation system
