IJCAS

A control problem of a class of input-delayed linear systems is considered in this paper. Due to the delay t in the input, any designed feedback controller can only be engaged after t t . Then, this can become the cause of slow regulation since any feedback information cannot be available during the delay. So, the initial function defined for 􀀀t t 0 is engaged as an ‘initial non-feedback input’ for 0 t t , which governs the system behavior during this initial time period. There have been numerous research results on the control of input-delayed linear systems by far. Yet, there have been no results on the examination and design of this initial function. Utilizing a time optimal control in the existing results, we show that if some pre-feedback as the initial function is engaged, the system response of the input-delayed linear system can be much improved, and a bang-bang input function is a good candidate as a pre-feedback which can provide better starting state values for the state feedback controller in order to perform the fast regulation. Two examples are given for the illustration of our results."

Keywords: Bang-bang control, fast regulation, input delay, pre-feedback.