Atherton D.P.Tan N.2024-08-042024-08-0420020191-2216https://hdl.handle.net/11616/90528IEEE Control Systems Society41st IEEE Conference on Decision and Control -- 10 December 2002 through 13 December 2002 -- Las Vegas, NV -- 60846The purpose of this paper is to study the problem of the absolute stability of nonlinear systems with variable plant parameters. New formulations of the circle and off axis circle criteria are developed which enable one to assess the stability of a control system containing a nonlinearity and plant with parametric uncertainties. In contrast to the classical approach which uses the Nyquist plot, the proposed method makes use of the narrowest possible Bode envelopes obtained from new results obtained by the authors where the plant transfer function is taken in factored form.eninfo:eu-repo/semantics/closedAccessBode diagramCircle criterionNonlinear control systemsOff axis circle criterionStabilityVariable plant parametersConference Object2228422852-s2.0-0036990439N/A