Abstract—This paper includes three main parts. The first part is about a Quadrotor as a type of unmanned vehicles. The second part includes its mathematical model and controlling with PID controller. The last part consists of some in flight and on ground testing. For the aforesaid processes first of all a Quadrotor has been built. The Quadrotor is designed within the Anadolu University which is the unique university because of its own airport. The design has some problems such as slow vibration speed, long response time and big movements in roll axes so some controlling applications have been developed. After ensuring its stabile flight, some sensor tests have been carried out to develop its control mechanism. Keywords—Flight control, PID controller, UAV. I. INTRODUCTION ince eras when people and flying creatures lived together, the act of flying has aroused the curiosity in the human mind. Such being the case, aviation sector becomes one of the fast-growing sectors along with technology. When analyzing the history of aviation, it is seen that air vehicles have ranged from balloon to unmanned aerial vehicles that is, they have varied greatly. This variation led the formation of air power concept which is of greatly importance in terms of defense industry over time. The governments recognize the importance of the air power has considerably invested in this field. Thanks to these investments, many features of the vehicle such as technical parameter, control algorithm, and maneuverability etc. have developed and increased. Accompany these, when the literature is analyzed, it is seen that the studies on this field have increased. For theoretical models of Quadrotor aerodynamics to be analyzed by using helicopter momentum and blade element theory [1], for an unknown parameter belongs to Quadrotor to be identified with the help of Unscented Kalman Filter [2], for adaptation to unknown payloads and robustness to disturbances to be achieved [3], for the method aiming at solved problems resulted from dynamic characteristics of a Quadrotor to be proposed [4], the design of The supported by Anadolu University Research Projects Committee (Project No. 1208F130) is gratefully acknowledged. G. Gol is with the Avionics Department, Anadolu University, Eskisehir, 26470 TURKEY (e-mail: gokhangol@anadolu.edu.tr). N. F. Bayraktar is with the Avionics Department, Anadolu University, Eskisehir, 26470 TURKEY (e-mail: nfbayraktar@anadolu.edu.tr). E. Kiyak is with the Avionics Department, Anadolu University, Eskisehir, 26470 TURKEY (corresponding author to provide phone: +90 222 335 05 80/6879; fax: +90 222 322 16 19; e-mail: ekiyak@anadolu.edu.tr). nonlinear modeling of Quadrotor and obtaining its mathematical model [5], Quadrotor performance and design of a PID controller for stabilization of the dominant decoupled pitch and roll models [6], for Quadrotor propellers to allow to tilt [7], for coaxial Quadrotor to be designed [8], for aerodynamic and mechanical model of UAV constructed from carbon composite material to be designed [9], for the nonlinear dynamic model of a Quadrotor and its controlling to be examined [10], developing a cascade control method for superheated processes [11], for the architecture of a Quadrotor and analyzes the dynamic model of it [12], an implementation of computer vision to hold a Quadrotor via a low-cost, consumer-grade, video system [13], using sliding mode disturbance observer approach for designing a robust flight controller [14], designing a controller making use of the block control technique for trajectory tracking of a Quadrotor [15], presentation nonlinear robust control method for solving the problems on path following [16], proposing attitude control strategy based on variable structure control theory [17], capable of attitude estimation and stabilization of unmanned aerial vehicle [18], analyzing the attitude control of a rigid body [19], Quadrotor flight in terms of vision-based obstacle avoidance [20], using genetic algorithms in PID controlling [21], simulation and the remote control of UAV [22], PID parameters self-tuning fuzzy control [23], an adaptive PID Control Approach [24], and lateral dynamic modeling and robust controlling of UAV [25] can be given as examples of the studies. When comparing the above mentioned studies, this paper focuses construction and balance stability of Quadrotor and obtaining some control parameters of the rotors. II. QUADROTOR The point on air vehicles reached in recent times is design of unmanned air vehicle (UAV). UAV have lots of important advantages. First of all, errors arise from human factor are minimized. This is of great significance in terms of reducing crashes. And also, it enables the possibility to saving space so they can be produce smaller sizes. Small sizes contribute high performance maneuverability, wide range of use, ease of control and command. Because unmanned vehicles have such features, they become one of the most engaging areas. UAV divide into some categories and have many different types. One of them is multi-copters. They can be termed as tricopter, Quadrotor, hexacopter, octocopter according to their rotor’s number. PID Controlling of the Quadrotor and Sensor Performance Tests G. Gol, N. F. Bayraktar and E. Kiyak S INTERNATIONAL JOURNAL OF CIRCUITS, SYSTEMS AND SIGNAL PROCESSING Volume 8, 2014 ISSN: 1998-4464 266