The main issue of our work is to develop a framework for troubleshooting which can be successfully applied to time-dependent domains. Continuing recent research work in the field of model-based diagnosis, we present a new approach to model-based monitoring and diagnosis of dynamic systems based on Qualitative Reasoning . We extend related research work which concentrates either on monitoring (i.e. fault detection) or on diagnosis (i.e. fault localization) and therefore misses important aspects of effective and efficient troubleshooting.
The presented DIAMON algorithm (DIAMON means DIAgnosis and MONitoring Algorithm) uses hierarchical models to monitor and diagnose dynamic systems. DIAMON is based on the integration of teleological parameter-based monitoring models and repair-oriented device-based diagnosis models. It combines consistency-based diagnosis with model-based monitoring and uses an extension of the QSIM-language for the representation of qualitative system models. Furthermore, DIAMON is able to detect and localize a broad range of non-permanent faults and thus extends traditional diagnosis which exclusively deals with permanent faulty behavior. We demonstrate the operation of DIAMON on two (non toy-world) technical systems in various fault scenarios.
Keywords: Monitoring and diagnosis, model-based diagnosis, diagnosis of dynamic systems
A preliminary version of the full paper is available as a postscript file .