Interactive tool for analysis of time-delay systems with dead-time compensators

Research output: Contribution to journalArticle


The problem of controlling delayed systems has been widely studied in the control community. The Smith predictor (SP) scheme was the most famous and efficient technique to cope with this problem. Afterwards, robustness problems and those related to the control of integrating and unstable delayed processes were resolved. This work presents an interactive tool for studying and understanding the different alternatives available for controlling systems with large delays. Interactive tools have provided excellent support for the control community during recent years. In this sense, the tool developed here helps to compare easily the performance of PID controllers and SP approaches for processes with delay, as well as other control structures used to solve different problems that the original SP has when integrator and unstable models are employed. Robustness problems due to presence of model uncertainties can also be analyzed. Furthermore, some real industrial processes are also described as motivation in the study of the problems presented in the paper. The tool incorporates a set of typical transfer functions based on these real industrial processes.


  • Jose Luis Guzman
  • Pedro Garcia
  • Tore Hägglund
  • Sebastian Dormido
  • Pedro Albertos
  • Manuel Berenguel
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Control Engineering


  • time-delay systems, smith predictor, delayed unstable processes, interactive tools, delayed integrating processes
Original languageEnglish
Pages (from-to)824-835
JournalControl Engineering Practice
Issue number7
Publication statusPublished - 2008
Publication categoryResearch