Passivity by Feedback

In the previous Chaps. 2 and 4, we have seen the importance of the notion of passivity, both for analysis and for control. This motivates to consider the problem of transforming a non-passive system into a passive system by the application of state feedback. We will give necessary as well as sufficient conditions for the solvability of this problem. The main idea in the proof of the sufficiency part is to transform the system into the feedback interconnection of two passive systems. This idea is further explored in Sect. 5.2 for the stabilization of cascaded systems, and leading in Sect. 5.3 to the technique of stabilization of systems with triangular structure known as backsteppin