KSME International Journal

, Volume 13, Issue 7, pp 517–523 | Cite as

Design of an observer for quantized output systems using orthogonal projection

  • Joono Sur
  • Young-il Park
Materials & Fracture · Solids & Structures · Dynamics & Control · Production & Design


This paper presents a state observer for linear systems with quantized outputs. The observer employs an orthogonal projection operation at quantizer output discontinuities to enhance its convergence rate for quantized output systems. Although there may be a significant quantization error on average, it is possible to design observers with an exponentially stable tracking error. We explain how to construct the orthogonal projection operation in a Hilbert space and prove the stability of the proposed observer by using the Lyapunov second method. In order to assess the value of the orthogonal projection operation in the proposed observer, the simple motor system with an optical encoder has been analyzed numerically.

Key Words

Observer Quantized Outputs Orthogonal Projection Lyapunov Method 


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Copyright information

© The Korean Society of Mechanical Engineers (KSME) 1999

Authors and Affiliations

  • Joono Sur
    • 1
  • Young-il Park
    • 2
  1. 1.Department of Mechanical EngineeringNaval AcademyChinhae KyungnamKorea
  2. 2.Department of Naval ArchitectureNaval AcademyChinhae KyungnamKorea

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