STUDY ON GAIN-SCHEDULING PROBLEM IN FLIGHT CONTROL

Gain-scheduling has gotits w ide applications in m odern flightcontrol, in w hich control gains are scheduled w ith variablessuch as dynam ic pressure and Mach num ber, to m eet dynam ic re- sponse requirem ents in different flight conditions. Classicalgain-scheduling approaches m ay resultin som e problem s, w hich can not guarantee globalrobustness and stability in transitions of different flight conditions. Gain-scheduling problem is system atically investigated from robustness point of view in the paper. Detailed procedures for gain-scheduled controller to achieve both robustness and stability perform ance are given and applied to a typicalflight controlsystem . For sw itching stability problem s ofdifferentflightconditionsin flightcontrolsystem s, a new approach isproposed, in w hich differentflight conditions are reduced into a param eter varying plant using interpolation firstly, and then param eter-varying controller design goes next. Though interpolation errors m ay exist, the ro- bustparam etervarying controller design can com pensate forthose uncertaintiesand errors, and final- ly achieve good perform ance ofrobustnessand sw itching stability during transitions. Illustrative sim - ulation atlastshow s satisfactory results.