Unfalsified Control; Application to automatic flight control system design

Abstract

Unfalsified Control Theory has been developed to provide a way for avoiding modeling uncertainties in controller design. It belongs to the class of control methods called Adaptive Supervisory Switching Control, which work by introducing in the control scheme a supervisory unit which chooses, from a set of candidate controllers the one most suited for the current plant. Unfalsified Control works by using a switching logic that dispenses with the need for a-priori knowledge of the dynamic model. At discrete moments of time, using the input/output data recorded up to that point, the supervisory calculates for each candidate controller a performance index, and compares it to a given threshold. Controllers surpassing that threshold are removed from the candidate controller set. This process is called falsification. If the controller in the loop is one such falsified controller it is replaced. In this paper we investigate the suitability of this method for aeronautical control applications. We review the theory behind this control scheme and adapt it to the case of controlling a fighter aircraft. We also provide a case study, where we test this control scheme on a simulated fighter aircraft.