On the sliding mode control of MIMO nonlinear systems: An input-output approach

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The approach is easy to implement. All is required to be precisely known is the order of the input-to-flat output system. The precise knowledge of the nonlinear gain of the system may be largely overlooked thanks to an homotopic equivalence, iinvariant with respect to practical stability, between time scaled unit gain systems and the original input-output system.

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