... arguments lead to a class of systems that we refer toas Linear Plant/Nonlinear Instrumentation (LPNI).The controllers in feedback systems are often designed to be linear. The main design techniques ... crash of a YF-22 airplane are examples of its failures. Even when this approach does work, itrequires a lengthy and expensive process of simulation and design/ redesign. Inaddition, designing controllers ... system control- theoretic developments of problems P1–P5, which parallel those of linear control theory, leading to what we call quasilinear control (QLC) theory.The question of accuracy of stochastic linearization,...