Cyclic Pseudo-Downsampled ILC

  • Danwei WangEmail author
  • Yongqiang Ye
  • Bin Zhang
Part of the Advances in Industrial Control book series (AIC)


In this chapter, a multi-rate cyclic pseudo-downsampled ILC is proposed. The scheme has the ability to deal with learning tasks with high frequency components and/or initial state errors. The error and input signals are downsampled to arrive at slow rate signals. Then, the downsampled slow rate signals are applied to ILC algorithm, whose output is then upsampled and applied to actuator. The novelty of the proposed scheme is that, for two successive iterations, the signal is downsampled but the down-sampling points are time shifted along the time axis. This shifting process makes the ILC scheme cyclic along the iteration axis with a period. Stability and robustness analysis shows that good learning transient can be guaranteed. Experimental results show significant tracking accuracy improvement.


Multi-rate Pseudo-down-sampling Cyclic down-sampling 


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Copyright information

© Springer Science+Business Media Singapore 2014

Authors and Affiliations

  1. 1.School of Electrical and Electronic EngineeringNanyang Technological UniversitySingaporeSingapore
  2. 2.College of Automation EngineeringNanjing University of Aeronautics and AstronauticsNanjingChina
  3. 3.Department of Electrical EngineeringUniversity of South CarolinaColumbiaUSA

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