Algorithms ror Designing Fault-Detection Experiments ror Sequential Machines

In this paper we present algorithms for designing fault-detection experiments for sequential machines with special emphasis on the case in which the machine does not possess a distinguishing sequence. The length of an experiment is reduced through: 1) identifying each state with its own unique input/output set rather than using a common set for all states; 2) utilizing overlapping of the required input/output sequences so that a portion of the experiment serves more than one purpose; and 3) verifying the reference condition in which the machine is placed at many points in the experiment by as short a locating sequence as possible. Important distinctions are made between locating sequences of the type introduced in previous work and those defined and used here.