Flight control applications with fuzzy logic method

ABSTRACT Master of Science Thesis FLIGHT CONTROL APPLICATIONS WITH FUZZY LOGIC METHOD Emre KIYAK Anadolu University Graduate School of Natural and Applied Sciences Civil Aviation Program Supervisor: Asst Prof. Dr. Ayşe KAHVECİO?LU 2003, 91 pages In daily life, human beings, come across some events that they are sure about it, but actually they are not certain. The final decision that they made, is according to the classical logic comprehension and have fairly certain limits. In the fuzzy logic concept, founded by Zadeh, as opposed to the classical logic, there are no certain limits. Being the human thought system, without needing an exact mathematical model and allowing to use of uncertain information, are a few of main advantages. It can be simply analyzed in three stages. In the first stage, which is called fuzzification, a membership grade, is given to the elements. Then, it forms some rules that are based on the logical relations. At the final stage, one result is obtained, making a defuzzification action like dasiccal logic. Fuzzy logic applications are widely used not only in the social, economic and technical areas, but also especially in the control engineering field. In this thesis, by using fuzzy logic, it was been attempted to build a model for the velocity and altitude which are very important aspects of control on the aircraft's longitutional axis, and a solution to the problems to give the correct degree to the flap which provides the proper lifting force at the landing and take off phases. Keywords: Fuzzy logic, flight control, modelling