A fault management system for longitudinal vehicle control in AHS

The design of a fault management system (FMS) for longitudinal control in automated highway systems (AHS) is presented. A hierarchical AHS architecture with vehicles organized in platoons is considered. The FMS is based on a fault identification module that presents a set of residuals to the FMS. The system handles up to twelve single different faults in the actuators, sensors and communication devices. Strategies to handle faults are divided into two groups. In the first group, redundancy of the fault detection schemes is exploited to substitute faulty information; normal mode operation of the AHS is still feasible if some critical parameters are adjusted. The second group contains faults whose occurrence requires specific degraded mode maneuvers to be executed. The FMS was implemented using SHIFT, a hybrid system simulation language. The simulation results obtained in SmartAHS, a micro-simulator for AHS based on SHIFT, are presented.