Enhancing Safety of Cyber-Physical Systems in Real Time

Cyber-Physical Systems (CPS) are advanced integrations of computational processes with physical operations, where embedded computing systems and networks actively monitor, control, and optimize physical entities through continuous feedback loops. Notable examples of CPS include autonomous vehicles, smart grids, and industrial control systems. Many CPS are safety-critical since they are authorized to have direct interaction with physical world and any failure in the system could lead to dangerous situations. For example, an autonomous vehicle fails to avoid obstacles can result in a collision. Therefore, it is important to provide safety solutions based on the application and scenarios. Safety and time are not independent of each other. A slow reaction to attacks can lead to unsafe conditions, an excessively fast controller can lead to unstable cases as well. Delays in responding to attacks can lead to catastrophic failures, while overly rapid responses may destabilize the system. Recognizing this, there is an imperative need to develop solutions that enhance CPS safety dynamically and efficiently, tailored to system requirements and evolving threat models. Building upon this insight that the safety solutions require tailoring to the system requirements and settings, my research agenda is centered around developing principle frameworks to make CPS more reliable and resilient, especially for real-time scenarios. My research focuses on developing frameworks that address CPS safety on multiple stages in real-time, each tailored to different levels of threat awareness: Prevention: Proactive Real-Time Defence. It is challenging to analyze the vulnerability to potential attacks before it happens. The safety condition of CPS can vary rapidly due to the changing context. Moreover, the analysis should be compatible with the existing attack detectors in the system to adapt to adversarial attacks. Mitigation: Real-Time Attack Recovery. It is important to respond to attacks after they were detected to mitigate their negative effects. In some cases, there is a very short time period between the attack detection to unsafe conditions. Therefore, it is important to react to the attack quickly and efficiently. Assurance: Safe Control Synthesis with Temporal Guarantee. Safety and timing assurance without attacks play an important role in the development of further security solutions against attacks. It is important to embed time and safety into controller design stage for CPS in safety-critical applications.