Fault detection in a linear cascade of identical machines

Many machines can be decomposed into a linear cascade of identical sequential machines. We consider the problem of implementing fault detection experiments for such machines. Cascade equivalence and information lossless properties of cascade machines are studied. Sufficient conditions for efficient testing of these machines are derived. Procedures are presented for testing cascades of arbitrary length N with either 2 or 3 simple present experiments. The total length of the fault detection sequence obtained by employing the methods presented is shown to be significantly less than if the classical testing procedures were taken.