Building Hybrid Observers for Complex Dynamic Systems Using Model Abstractions

Controllers for embedded dynamic systems require models with continuous behavior evolution and discrete configuration changes. These changes may cause fast continuous transients in state variables. Time scale and parameter abstractions simplify the analysis of these transients, causing discontinuities in the state variables. The two abstraction types have a very different impact on the analysis of system behavior. We have developed a systematic modeling approach that introduces formal semantics for behavior generation. This paper discusses the implementation of this scheme in a hybrid observer designed to track embedded system behavior. The resultant observer is based on piecewise simpler continuous models with mode transitions defined between them. Actual mode transitions in the system are provided by a digital controller and directly obtained from measuring physical variables.

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