Method of Quasi-Optimal Synthesis Using Invariants Andrey Aleksandrovich Kostoglotov, Sergey Valerievich Lazarenko, Anton Aleksandrovich Kuznetcov and Zoya Vladimirovna Lyashchenko MATEC Web Conf., 77 (2016) 15003 Published online: 03 October 2016 DOI: 10.1051/matecconf/20167715003