Residual Sinks Accounting for Uncertainties

In the previous section, a behavioural model of the faulty system and a non-faulty system model with nominal parameters have been coupled by residual sinks that 

4 Bond Graph Model-based Quantitative FDI in Hybrid Systems 

As long as the absolute value Afi (f) = fi(t)- fi(t) is below a given threshold thfi, the signal Si modulating the residual sinkrSej is set to zero and the sink remains 

The threshold thri may be a constant chosen on the basis of experience for each system mode or a function of variables and thus may be time dependent. 

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