Kybernetika 51 no. 5, 856-873, 2015

Sum-of-squares based observer design for polynomial systems with a known fixed time delay

Branislav RehákDOI: 10.14736/kyb-2015-5-0856


An observer for a system with polynomial nonlinearities is designed. The system is assumed to exhibit a time delay whose value is supposed to be constant and known. The design is carried out using the sum-of-squares method. The key point is defining a suitable Lyapunov-Krasovskii functional. The resulting observer is in form of a polynomial in the observable variables. The results are illustrated by two examples.


observer, sum-of-squares polynomial, polynomial system




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