Practical considerations for implementing intrinsic fault recovery in embedded systems

Evolvable hardware provides a viable fault recovery technique for embedded systems already deployed into an operational environment. Typically the fitness of each evolved configuration in such systems must be intrinsically determined because imprecise information about faults makes extrinsic methods impractical. Most work on intrinsic circuit evolution is conducted in laboratory environments where sophisticated measurement equipment is readily available and frequency domain analysis poses no real problems. In this paper we argue intrinsic fault recovery for embedded systems has to be done in the time domain. We report the results of several experiments conducted to identify potential problems with determining fitness in the time domain for embedded systems. We also discuss the limitations embedded systems impose on GAs used for evolvable hardware applications and suggest some possible solutions.