Analysis of Discrete-Time Disturbance Observer for Second-Order Systems

2차 시스템에 대한 이산시간 외란 관측기의 분석

  • 양광진 (공군사관학교 기계공학과) ;
  • 최영진 (한국과학기술연구원 지능로봇연구센터) ;
  • 정완균 (포항공과대학교 기계공학과)
  • Published : 2003.06.01


The disturbance observer(DOB) has been widely used in high speed and high precision motion control applications and the characteristics of DOB have been investigated in depth. Though most of DOB's have been implemented as the discrete-time form in digital devices, we are still short of the researches on discrete-time DOB (DDOB) in spite of rich references on continuous-time DOB. In this paper, we discuss about the disturbance rejection property and measurement noise effect of discrete-time DOB. Especially, we will focus on revealing the role of sampling time in designing the discrete-time DOB and show the validity of analysis through simulations and experiments for optical disk drive systems.



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