Nachweislich sichere Bewegungsplanung für autonome Fahrzeuge durch Echtzeitverifikation

This thesis introduces fail-safe motion planning as the first approach to guarantee legal safety of autonomous vehicles in arbitrary traffic situations. The proposed safety layer verifies whether intended trajectories comply with legal safety and provides fail-safe trajectories when intended trajectories result in safety-critical situations. The presented results indicate that the use of fail-safe motion planning can drastically reduce the number of traffic accidents.Die vorliegende Arbeit führt ein neuartiges Verifikationsverfahren ein, mit dessen Hilfe zum ersten Mal die verkehrsregelkonforme Sicherheit von autonomen Fahrzeugen gewährleistet werden kann. Das Verifikationsverfahren überprüft, ob geplante Trajektorien sicher sind und generiert Rückfalltrajektorien falls diese zu einer unsicheren Situation führen. Die Ergebnisse zeigen, dass die Verwendung des Verfahrens zu einer deutlichen Reduktion von Verkehrsunfällen führt

Safety Verification of Automated Driving Systems

n this paper, a set based approach is presented for safety verification and performance analysis of automated driving systems. As an example, reachability analysis technique is used to study the minimum required safe inter-vehicle distance for two given adaptive cruise controllers, a state feedback and a state feedback/feedforward controller designed based on mixed d H2/3 control. Not surprisingly, the results indicate that a shorter inter-vehicle distance can be achieved when a feedforward term used in the controller. In addition, we show how backward reachability analysis and invariant set theory can be used to find the Maximal Admissible Safe Set. This is defined as the set of position error, relative speeds and acceleration, which a given controller is guaranteed to control to the desired speed and inter-vehicle distance, while fulfilling vehicle physical constraints and avoiding rear-end collisions with the preceding vehicle. The calculation of the Maximal Admissible Safe Set is demonstrated for the two aforementioned controllers. Furthermore, the presented verification method is extended to account for the case of vehicle model with polytopic uncertainties and delay. The results on the reachability analysis are verified experimentally using an emergency braking scenario