Completed notes of the course

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Aeroservoelasticity of fixed and rotary wing aircraft ILAF : IDENTICAL LOCATED ACCELERATION AND FORCE - IF I GENERATE A FORCE SO THAT F & - U I'LL OBTAINA DAMPINGEFFECT FORCE MUST BE APPLIED WHERE I MEASURE THE SPEED SO THAT F, U WILL B.EIN PHASE NO INSTABILITIES • PROBLEM : THE DEFLECTION OF TITE FLAP PRODUCES THE DE512ED FORCE, B.UT ALSO A MOMENT UU11-1CHMAKES THINGS MORE COMPLICATED • GENERALLYSPEEDIS OBTAINED INTEGRATING ACCELERATION COMINGFROM ACCELEROMETERS SENSOR INTEGRATOR HIGHPASS GA1NFILTER MOVABLEAEROELASTICITY SURFACE L "✗ STRUCTURE⊥ /h.0.P .i.i.fi,ii.i.f)- K AERODYNAMICS - IF I GENERATEA FORCE PROPORTIONAL TO - [' OBTAIN A DAMPING EFFECT • REMARK: SINCE IN OUR MODEL hIS POSITIVE DOWNWARD AND L POSITIVE UPWARD I DON'T NEED TO PUT - K PHYSICAL PROBLEM: WE CAN'TINJECT FORCE DIRECTLY IN OUR SYSTEM : WENEEDTO ADD CONTROLSURFACES THEOUTPUTOF OUR CONTROLSYSTEM MUST BE AROTATION OF THE CONTROL SURFACE - HOW FAR CAN I INCREASE THE GAIN?THEMOREI INCREASETHE GAIN THE MORE ENERGY IS REQUIRED TO STABILIZE THE SYSTEM (I. E. DAMPOUT OSCILLATIONS ) PROCEDURE: SET A CERTAIN SPEED AND EVALUATE THEROOT LOCUS INCREASING THE CA1N UNTIL WE REACH THE LIMIT ' it' 5 BEIT-62 TO SIMULATE THE RESPONSE OF THE SYSTEM TO A CONTINUOUS INPUT INJECT A SINUSOIDAL GUST SPEED WITH f-=6HZ • I OBTAIN A ROTATION OF THE FLAP OF 14° 't'SEXCESSIVE: THERE'SNOROOMFOR TITEPILOT TO CONTROLTITEAIRCRAFT • IF I FURTHER INCREASE THEGAIN IT GETS EVEN WORSE > IF I CHANGETHEFREQUENCYOF THEDISTURBANCE TO f-= 2HZI OBTAINTHEOPPOSITEEFFECT: THEMOREIINCREASETHEGAINTHEMOREI STABILIZE WHY?AT f-= 6HZ I WAS CLOSE TO RESONANCE • WEHAVE LEARNT TITAT THE CONTROLSYSTEMIS LIMITED BY: THEREQUIREDPOWER THE DEFLECTION ANGLEOF THE CONTROLSURFACE ' MC-T11-0DS TO DEVELOP A CONTROLSYSTEM : 1) WORK ON SENSORS I MANAGE THE HINGE…