Health index and behaviour based vehicle level reasoning system

The diagnostics and prognostics are vital parts of the integrated vehicle health management technology. In today´s aircraft the diagnostic and prognostic systems play a crucial part in aircraft safety while reducing the operating and maintenance costs. Aircraft are very complex in their design and require consistent monitoring of systems to establish the overall vehicle health status. Many diagnostic systems utilize advanced algorithms (e.g. Bayesian belief networks or neural networks) which usually operate at system or sub-system level. The subsystem reasoners collect the input from components and sensors to process the data and provide the diagnostic/detection results to the flight advisory unit. Generally, a diagnostic system processes the sensor data and provides results; however the behaviors of the machine are not accounted by the diagnostics system. This article provides a novel vehicle level reasoning system, where the health index and system behaviors are also considered with subsystem generated results. Each sub-system´s health index is also calculated and passed to the VLRS.