Distributed Denial-of-Service Resilient Control for Urban Air Mobility Applications

Urban air mobility (UAM) systems are characterized by the heterogeneity of participating aerial vehicles (AVs). Participating AVs are expected to cooperate with each other while maintaining flexibility in individual missions and reacting to the possibility of cyberattacks and security threats. In this paper, we focus on the vulnerabilities of the UAM cyberphysical system against distributed denial-of-service (DDOS) cyberattacks. We develop a resilient control strategy for the AVs navigating through the UAM airspace to mitigate the effect of DDOS cyberattacks. A graph-theoretic vulnerability metric is proposed. Each AV can compute its vulnerability against DDOS cyberattacks in a fully distributed manner using this metric. Based on this computed metric, the AVs self-organize to minimize collision risk in the operating airspace after assessing self-vulnerability. This reconfiguration is also carried out in a fully distributed manner. The proposed resilient control is proven to reduce vulnerability in a probabilistic manner. This reduced vulnerability holds against DDOS cyberattacks with a known attack budget.