Discussion on: 'Unified Approach to the Problem of Full Decoupling via Output Feedback'

摘要

The article under discussion studies the unmeasurable disturbance decoupling problem (DDP) via the dynamic output feedback from a unified viewpoint for continuous-and discrete-time nonlinear control systems as well as for discrete event systems. This is a challenging problem, not having today a complete solution, that is the necessary and sufficient solvability conditions together with the constructive algorithm to compute the feedback law. In [1] the intrinsic coordinate-free necessary solvability conditions were obtained in terms of the maximal conditioned invariant subspace and the smallest controlled invariant subspace. The article under discussion provides the sufficient algorithm-based solvability conditions. Unfortunately it does not provide the explicit algorithm for problem solution; the steps of the algorithm are scattered implicitly in the different parts of the article, partly presented in the unified manner, partly treated separately for the continuous and discrete cases.