A complete fault diagnostic system for automated vehicles operating in a platoon

A "complete" fault diagnostic system is developed for automated vehicles op erating as a platoon on an automated highway system. The diagnostic system is designed to monitor the complete set of sensors and actuators used by th e lateral and longitudinal controllers of the vehicle, including radar sens ors, magnetometers and inter-vehicle communication systems, A fault in any of the twelve sensors and three actuators is identified without requiring a ny additional hardware redundancy. The diagnostic system uses parity equati ons and several reduced-order nonlinear observers constructed from a simpli fied dynamic model of the vehicle. Nonlinear observer design techniques are used to guarantee asymptotically stable convergence of estimates for the n onlinear dynamic system. Different combinations of the observer estimates a nd the available sensor measurements are then processed to construct a bank of residues. The paper analytically shows that a fault in any one of the s ensors or actuators creates a unique subset of these residues to grow so as to enable exact identification of the faulty component. Both simulation an d experimental results are presented to demonstrate the effectiveness of th e fault diagnostic system in the presence of various faults.