Robust stability of controlled third order systems / V. V. Aleksandrov, G. Yu. Sidorenko, I. O. Zueva. //Vestnik Moskovskogo Universiteta. Seriya 1. Matematika. Mekhanika. 2014. № 1. P. 39-45 [Moscow Univ. Math. Bulletin. Vol. 69, N 1, 2014.].
Application of variational methods in stability theory leads to new results in the case of control systems whose description includes various parameters known up to some sets. This paper attempts to consider these possibilities by the example of expansion of the classical concept of stability under constantly acting perturbations introduced by G.N. Duboshin and I.G. Malkin in 1941-1944.
Key words: robust stability, stability under constantly acting perturbations, limit cycle, auto-oscillations.