An Unknown Input Multi-Observer Approach for Estimation, Attack Isolation, and Control of LTI Systems under Actuator Attacks
Provides a theoretical framework for secure control of LTI systems against actuator attacks, relevant for safety-critical cyber-physical systems.
Proposed a bank of Unknown Input Observers for state estimation, attack isolation, and control of LTI systems under actuator attacks, achieving exponential stability when few actuators are compromised. Simulations demonstrate effectiveness.
We address the problem of state estimation, attack isolation, and control for discrete-time Linear Time Invariant (LTI) systems under (potentially unbounded) actuator false data injection attacks. Using a bank of Unknown Input Observers (UIOs), each observer leading to an exponentially stable estimation error in the attack-free case, we propose an estimator that provides exponential estimates of the system state and the attack signals when a sufficiently small number of actuators are attacked. We use these estimates to control the system and isolate actuator attacks. Simulations results are presented to illustrate the performance of the results.