QFT BASED ROBUST CONTROLLER DESIGN FOR LAUNCH VEHICLE AUTOPILOT

摘要

This paper addresses the autopilot design for a typical launch vehicle in the Quantitative Feedback Theory (QFT) framework. Plant uncertainty is accounted at the modelling phase itself - the uncertain plant is described in terms of a set of transfer functions covering the entire phase of flight. A robust controller is designed to meet the system specifications, which have been translated into QFT bounds . The performance of the system at different flight instants throughout the stage has been evaluated through frequency response and transient response studies. A satisfactory design is obtained with a low order controller.