Masters Theses


Qing Liu


"In automation control area, with the increasing demand in task complexity and high control precision, coordination between systems is required. There are mainly two types of coordinated systems, decentralized and centralized. This thesis is focused on a large array of coordinated systems, and the decentralized structure is preferred. To achieve high control precision in a coordinated system, many existing approaches may work, and in the system performing the repeating process, Iterative Learning Control (ILC) is a useful approach. Therefore, in this thesis, a decentralized coordinated ILC system is proposed and analyzed. The proposed control system is especially useful in coordinating a large array of systems.

Transient growth is a common problem in both single and coordinated ILC systems. Several ILC algorithms have been developed that can guarantee monotonic convergence, but these algorithms are not feasible or do not work well in decentralized coordinated ILC systems. This thesis presents a new approach to reduce the transient growth in ILC. An iteration-varying filter, which can be applied to any linear ILC system, single or coordinated, is proposed. It is also proved that the filter always exists when the ILC system is stable. A theoretical result and a tuning approach are given in the thesis to design the filter.

Two examples, one single system and one coordinated system, are presented to show the design of a decentralized coordinated ILC system and the effectiveness of the iteration-varying filter"--Abstract, page iii.


Bristow, Douglas A.

Committee Member(s)

Balakrishnan, S. N.
Sarangapani, Jagannathan, 1965-


Mechanical and Aerospace Engineering

Degree Name

M.S. in Mechanical Engineering


Missouri University of Science and Technology

Publication Date

Fall 2010


x, 78 pages

Note about bibliography

Includes bibliographical references (pages 75-77).


© 2010 Qing Liu, All rights reserved.

Document Type

Thesis - Open Access

File Type




Thesis Number

T 11361

Electronic OCLC #