A fault-tolerant real-time supervisory scheme for an interconnected four-tank system

In this paper, the implementation of a Command Governor (CG) strategy on a real-time computing system is described for the supervision of a laboratory four-tank test-bed. In particular, the real-time architecture has been developed on the RTAI/Linux operating system kernel and the CG module has been implemented in C++ on a general purpose off-the-shelf computing unit. An accurate model of the the four-tank process has been derived from both physical and experimental data and the applicability of the proposed method has been proved by means of real-time tests, which testified on the CG strategy ability to enforce the prescribed operative constraints even under unexpected adverse conditions, e.g. water pumps failures.

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