On the Practicality of Intrinsic Reconfiguration As a Fault Recovery Method in Analog Systems

Evolvable hardware combines the powerful search capability of evolutionary algorithms with the flexibility of reprogrammable devices, thereby providing a natural framework for reconfiguration. This framework has generated an interest in using evolvable hardware for fault-tolerant systems because reconfiguration can effectively deal with hardware faults whenever it is impossible to provide spares. But systems cannot tolerate faults indefinitely, which means reconfiguration does have a deadline. The focus of previous evolvable hardware research relating to fault-tolerance has been primarily restricted to restoring functionality, with no real consideration of time constraints. In this paper we are concerned with evolvable hardware performing reconfiguration under deadline constraints. In particular, we investigate reconfigurable hardware that undergoes intrinsic evolution. We show that fault recovery done by intrinsic reconfiguration has some restrictions, which designers cannot ignore.