Varun Khemani, Michael H. Azarian and Michael Pecht
Center for Advanced Life Cycle Engineering (CALCE), University of Maryland, College Park, MD, USA
Abstract:
Analog circuits are a critical part of industrial electronics and systems. Estimates in the
literature show that, even though analog circuits comprise less than 20% of all circuits, they are
responsible for more than 80% of faults. Hence, analog circuit fault diagnosis and isolation can be a
valuable means of ensuring the reliability of circuits. This paper introduces a novel technique of
learning time–frequency representations, using learnable wavelet scattering networks, for the fault
diagnosis of circuits and rotating machinery. Wavelet scattering networks, which are fixed time–
frequency representations based on existing wavelets, are modified to be learnable so that they can
learn features that are optimal for fault diagnosis. The learnable wavelet scattering networks are
developed using the genetic algorithm-based optimization of second-generation wavelet transform
operators. The simulation and experimental results for the diagnosis of analog circuit faults demonstrates that the developed diagnosis scheme achieves greater fault diagnosis accuracy than other
methods in the literature, even while considering a larger number of fault classes. The performance
of the diagnosis scheme on benchmark datasets of bearing faults and gear faults shows that the
developed method generalizes well to fault diagnosis in multiple domains and has good transfer
learning performance, too.