Design for general Hinfinity almost disturbance decoupling problem with measurement feedback and internal stability an eigenstructure assignment approach

Feedback controllers, explicitly parameterized in a single parameter epsilon, are constructed to solve the well-known Hinfinity almost disturbance decoupling problem with measurement feedback and with internal stability (Hinfinity-ADDPMS) for continuous-time linear systems. The construction of these feedback laws utilizes eigenstructure assignment algorithms and does not involve the solution of any parameterized algebraic Riccati equations. As a result, the coefficients of the feedback laws are explicitly given as polynomial matrices in epsilon. The results generalize the earlier work of Ozcetin et al. by allowing the system to have invariant zeros on the imaginary axis. Such a generalization is motivated by the recent development of low-gain feedback design technique.