Navigation and Localization
The navigation is based on virtual 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 and wheel configuration.
2getthere’s vehicles use localization based on odometry in combination with 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. Where state-of-the-art localization based on natural landmarks will allow for a 90% availability relative to weather circumstances, artificial landmarks will allow for >99% availability. 2getthere’s software is agnostic and can accommodate both.
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.