ABSTRACT
Both of them are concerned with stability/attractivity concepts because:
• in the first step, the condition ensuring the sliding motions is a contraction property (at least locally around the sliding manifold),
• in the second one, the choice of the surface (shaping procedure) is mostly related to some stabilization problem: one has to compute (or "tune" ) the parameters involved in the shape of the sliding surface such that the sliding motions achieve some convergence and/or stabilization problem.
