Abstract：To investigate a class of nonlinear systems with uncertainties and external disturbances, a finite time extended state observer is designed to estimate the uncertainties and external disturbances in finite time. Compared to standard extended state observer, based on the idea of terminal sliding mode, the observer makes use of fractional powers to reduce extended state error to zero in finite time, and then strengthen the robustness. A sufficient condition on the issue of finite time stability is established through the theory of Lyapunov, and finally, an illustrative numerical simulation is given to demonstrate the effectiveness of the strategy proposed.
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2017, Vol. 38 
