The navigation is based on pre-defined routes. Vehicles follow the received set points for the routes, based on a robust and complex algorithm which controls multiple physical points of the vehicle. They keep track of their position by measuring distance (wheel revolutions) and the direction of travel (steering angle and gyro). The desired routes are followed within centimeters accuracy, even at high speeds (60km/h). The navigation control software is modular and generic in architecture, supporting any vehicle type.
Localization is based on natural or artificial landmarks. Where natural landmarks require line-of-sight (detection by means of camera, Lidar or GPS), artificial landmarks (magnets or transponders) need to be physically added. In between reference points vehicles track their position through odometry. 2getthere normally applies its patented magnet measurement system, allowing reliable operations during all weather conditions. As the localization software is agnostic to the calibration used, localization based on natural landmarks is also possible.
Each vehicle has a Vehicle Control System (VCS), which communicates with subsystems dedicated to control or messaging tasks in a master-servant relation. The subsystems operate as independently as possible, enabling exchange without high impact. The guidance control system (GCS) keeps an up-to- date estimation of the current position and generates set-points for steering, driving, and braking. For redundancy multiple wheel revolution sensors, steering angle sensors and orientation sensors are mounted to both the driven and steered wheels.