A remark on “nonlinear output feedback control of underwater vehicle propellers using feedback form estimated axial flow velocity”

J. Jouffroy, J. Lottin

Publikation: Bidrag til tidsskriftTidsskriftsartikelForskningpeer review


In the work presented by Fossen and Blanke, a nonlinear observer for estimation of propeller axial flow velocity for UUVs was introduced. The proof of the convergence behavior of the observer was carried out with a Lyapunov analysis. In this technical communication, such an analysis was also briefly compared with the so-called contraction analysis. This communication goes further into the details of the comparison by proving - through a link between contracting and globally exponentially stable (GES) systems - that the observer is both contracting and GES, showing thus that contraction analysis might be regarded as an interesting alternative to Lyapunov-based designs. Furthermore, some qualitative advantages gained when using contraction analysis are given.
TidsskriftIEEE Journal of Oceanic Engineering
StatusUdgivet - 2002
Udgivet eksterntJa


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