FDIR Techniques If-then-else Hard coded set of fdir statements Rule-based Set of rules written by the engineers Fires a rule (i.e. executes a rule) when the rule is satisfied EXample #24(D>1A)And(Shunt D> 6A)for 10 sec, then Try Sec Bus Reg_ Off #27 (Red Battery Charger is ON) for 5 sec, then rule(28, 29 )stop The core software is reusable Engineers must enumerate all possible faults and combinations thereof along with the corresponding recovery methods Verifying the validity of the rules is difficult Massachusetts Institute of Technology5 Massachusetts Institute of Technology FDIR Techniques • If-then-else – Hard coded set of FDIR statements • Rule-based – Set of rules written by the engineers – Fires a rule (i.e. executes a rule) when the rule is satisfied – Example • #24 (ID > 1A) And (Ishunt_D > 6A) for 10 sec, then Try_Sec_Bus_Reg_Off. • #27 (Red Battery Charger is ON) for 5 sec, then rule (28,29) stop. – The core software is reusable. – Engineers must enumerate all possible faults and combinations thereof along with the corresponding recovery methods. – Verifying the validity of the rules is difficult