Abstract: Rudder circuit is an important part of flight control system of UAV(unmanned aerial vehicle).Flight control system could control the angle motion of UAV via the rudder circuit,in order to achieve its stable flight.Based on a model of hysteresis motors and "Taguchi" three design methods, the effect on the rudder circuit by feedback of position and velocity is analyzed, its value range is determined, a certain type of UAV rudder circuit is designed.The test results of simulation experiment show that the design is feasible.

Key words: UAV, Hysteresis motors, Rudder circuit