Introduction to time-delay and sampled-data systems

Time-delay naturally appears in many control systems, and it is frequently a source of instability. However, for some systems, the presence of delay can have a stabilizing effect. Therefore, stability and control of time-delay systems is of theoretical and practical importance. Modern control systems usually employ digital technology for controller implementation, i.e. sampled-data control. A time-delay approach to sampled-data control, where the system is modeled as a continuous-time system with the delayed control input became popular in the networked control systems, where the plant and the controller exchange data via communication network. In the present Tutorial, introduction to time-delay systems will be given together with some advanced results on the topic.