, Volume 21, Issue 4, pp 435–463 | Cite as

Adaptive optimal tuning of a general class of stable LTI systems with restricted inputs

  • H N ShankarEmail author
  • K Rajgopal


The problem addressed is one of model reference adaptive control (MRAC) of asymptotically stable plants of unknown order with zeros located anywhere in thes-plane except at the origin. The reference model is also asymptotically stable and lacking zero(s) ats = 0. The control law is to be specified only in terms of the inputs to and outputs of the plant and the reference model. For inputs from a class of functions that approach a non-zero constant, the problem is formulated in an optimal control framework. By successive refinements of the sub-optimal laws proposed here, two schemes are finally designed. These schemes are characterized by boundedness, convergence and optimality. Simplicity and total time-domain implementation are the additional striking features. Simulations to demonstrate the efficacy of the control schemes are presented.


Model reference adaptive control nonminimum phase unknown order optimal control 


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Copyright information

© Indian Academy of Sciences 1996

Authors and Affiliations

  1. 1.Department of Electrical EngineeringIndian Institute of ScienceBangaloreIndia

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