Automatic helicopter motion control using fuzzy logic

This paper describes the application of the fuzzy logic control (FLC) theory to control the helicopter flight on two basic flight modes: hovering and forward. Hovering is a formidable stability problem, where helicopter pilots typically train for weeks before managing to do it manually. Hence automating this operation is in itself an impressive achievement. In this work, four FLC´s execute control rules that represent the linguistic knowledge used by helicopter pilots and found as verbal description in pilot operating manuals. For each flight mode it is used two FLC´s where the outputs corresponds to the pitch angle of longitudinal and lateral cyclic. For the hover flight mode the controllers variable input are the pitch attitude and pitch rate of the fuselage for the first controller and the roll angle and roll rate of fuselage for the second controller to control the side and forward velocity through the pitch angle of lateral and longitudinal cyclic. In the forward flight mode, it is used three variable input for each controller where four of them are the same used in the hover flight mode and it is also used the forward velocity variable in both controllers. Simulation results are presented, showing the effectiveness of the proposed FLC´s for both flight modes.