A Learning Method of LQR Controller using Increasing or Decreasing Information in Input-Output Relationship

입출력의 증감 정보를 이용한 LQR 제어기 학습법

  • 정병묵 (영남대학교 공과대학 기계공학부)
  • Published : 2006.09.01

Abstract

The synthesis of optimal controllers for multivariable systems usually requires an accurate linear model of the plant dynamics. Real systems, however, contain nonlinearities and high-order dynamics that may be difficult to model using conventional techniques. This paper presents a novel loaming method for the synthesis of LQR controllers that doesn't require explicit modeling of the plant dynamics. This method utilizes the sign of Jacobian and gradient descent techniques to iteratively reduce the LQR objective function. It becomes easier and more convenient because it is relatively very easy to get the sign of Jacobian instead of its Jacobian. Simulations involving an overhead crane and a hydrofoil catamaran show that the proposed LQR-LC algorithm improves controller performance, even when the Jacobian information is estimated from input-output data.

Keywords

References

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