Departmental Papers (ESE)


Large-scale control systems typically possess a hierarchical architecture in order to manage complexity. Higher levels of the hierarchy utilize coarser models of the system, resulting from aggregating the detailed lower level models. In this layered control paradigm, the notion of hierarchical consistency is important, as it ensures the implementation of high-level objectives by the lower level system. In this paper, we define a notion of modeling hierarchy for continuous control systems and obtain characterizations for hierarchically consistent linear systems with respect to controllability objectives. As an interesting byproduct, we obtain a hierarchical controllability criterion for linear systems from which we recover the best of the known controllability algorithms from numerical linear algebra.

Document Type

Journal Article

Subject Area


Date of this Version

June 2000


Copyright 2000 IEEE. Reprinted from IEEE Transactions on Automatic Control, Volume 45, Issue 6, June 2000, pages 1144-1160.
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abstraction, consistency, controllability algorithms, hierarchical control, continuous time systems, controllability, hierarchical systems, large-scale systems, linear algebra, linear systems, consistency, continuous control systems, linear systems



Date Posted: 30 April 2005

This document has been peer reviewed.