“…After a transient phase, called "reaching phase", during which the insensitiveness of the system with respect to the uncertain terms is not guaranteed, the so-called "sliding phase" starts and the controlled system proves to be robust versus a specific class of uncertainties, the so-called "matched uncertainties", i.e., uncertain terms which act on the same channel of the control variable. The main drawback of SMC is the so-called chattering phenomenon, i.e., oscillations of the controlled variable due to the discontinuity of the control input [Boiko et al, 2007;Levant, 2010]. The most effective solution to alleviate this phenomenon is the generation of higher order sliding modes (HOSM), which are able to reduce the chattering effect while maintaining good stability properties [Bartolini et al, 1998[Bartolini et al, , 2000Levant, 2003;Dinuzzo and Ferrara, 2009;Ferrara et al, 2014b].…”