Framework for a Uniform Description of Prognostics and Health Management

Abstract

The successful application of Prognostics and Health Management (PHM) systems is increasing steadily worldwide. One reason for this is the increasing number of smart products entering the market. Mirroring smart products, PHM systems are now developed and applied in a
variety of engineering disciplines, all using different models and methods. Model, method, and product type diversity all lead to highly complex systems. To handle the complexity in an efficient way, this paper introduces a common base for PHM systems, in the form of a framework – the goal being a generic model with clear formalization of both notation and semantics. Accordingly, the PHM System is separated into both a RUL-Health model and a context model. Both are described and connected through a roles and relation model of their modules. Diagnosis and prognosis modules – estimating the components’ health using lifetime models – are RUL-Health based. For a holistic description, the general lifetime model (GLM) is introduced. This allows different measures of component health to be represented in a single model and reduces the complexity to two metrics – remaining useful life (RUL) and health index (HI). These metrics – combined with internal/external requirements & targets – are
the input for the context modules’ optimization and decision making.