Process control: the passive systems approach

passive system cannot de-liver more energy than what is stored. Typically, a passive system delivers less than what is stored since useful ener-gy is invariably and irreversibly lost through friction and other dissipative processes that convert useful work into heat. Such prop-erties show that passivity is relat-ed to principles used to develop mathematical models for all kinds of physical systems. Ap-plications of passivity-based control methods are found in robotics [1]–[3], systems biology [4], large-scale systems analysis [5], [6], and chemical process control [7]. One o