A Study on Singularly Perturbed Open-Loop Systems by Delta Operator Approach

  • Shim, Kyu-Hong (Sejong-Lockheed Martin Aerospace Research Center Sejong University) ;
  • M. Edwin Sawan (Dept. of Electrical and Computer Engineering, Wichita State University, Kansas)
  • Published : 2001.12.01

Abstract

In this paper, the open-loop state response of the two-time-scale systems by unified approach using the $\delta$-operator is presented with an example of the aircraft longitudinal dynamics. First, the $\delta$-operator system unifies both the continuous system and the discrete system simultaneously, and the $\delta$-operator approach improves the finite word-length characteristics. This saves more computing time than that of the discrete system. Second, the singular perturbation method by block diagonalization reduces the sizes and orders of the systems. This also reduces the floating-point operations (flops). The advantage of those two approaches is shown by comparing our results with the earlier ones in the illustrative example of the longitudinal motion of F-8 aircraft.

Keywords

References

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