Towards Formal Verification of Freeway Traffic Control

Title
Towards Formal Verification of Freeway Traffic Control

Authors
Stefan Mitsch
Marshall-Plan Scholar, Johannes Kepler University
Sarah M. Loos, Andre Platzer
Computer Science Department, Carnegie Mellon University Pittsburgh

Abstract
We study how CPS technology can help improve freeway traffic by combining local car GPS positioning, traffic center control decisions, and communication to achieve more tightly coupled feedback control in intelligent speed adaptation. We develop models for an intelligent speed adaptation that respects variable speed limit control and incident management. We identify safe ranges for crucial design parameters in these systems and, using the theorem prover KeYmaera, formally verify safety of the resulting CPS models. Finally, we show how those parameter ranges can be used to decide trade-offs for practical system implementations even for design parameters that are not modeled formally. Index Terms--Freeway traffic control, intelligent speed adaptation, hybrid system