Experimental active control of a typical section using a trailing-edge flap

This paper presents an experimental implementation of an active control system used to suppress flutter in a typical section airfoil. The H-2 optimal control system design is based on experimental system identifications of the transfer functions between three measured system variables-pitch, plunge, and flap position-and a single control signal that commands the flap of the airfoil. Closed-loop response of the airfoil demonstrated gust alleviation below the open-loop flutter boundary, In addition, the flutter boundary was extended by 12.4% through the application of active control, Cursory robustness tests demonstrate stable control for variations in now speed of +/-10%.