Navigation algorithms and autopilot application for an unmanned airvehicle

Kahraman, Eren
This study describes the design and implementation of the altitude and heading autopilot algorithms for a fixed wing unmanned air vehicle and navigation algorithm for attitude and heading reference outputs. Algorithm development is based on the nonlinear mathematical model of Middle East Technical University Tactical Unmanned Air Vehicle (METU TUAV), which is linearized at a selected trim condition. A comparison of nonlinear and linear mathematical models is also done. Based on the linear mathematical model of the METU TUAV, the classical control methods are applied during the design process of autopilot algorithms. For the confirmation purposes of the autopilot and navigation algorithms, a nonlinear simulation environment is developed in Matlab/Simulink including nonlinear model of the METU TUAV, altitude and heading autopilot loops, nonlinear actuator models, sensor models and navigation model. In the first part of the thesis, feedback signals for the controller are provided by IMU free measurements. In the second part, the feedback signals are provided by an attitude and heading reference mode, which incorporates the gyroscope solutions with the magnetic sensor and accelerometer sensor measurements by using a Kalman filter algorithm. The performance comparison of the controller is done for both cases where the effects of having different modes of the measurement sources are investigated.


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Citation Formats
E. Kahraman, “Navigation algorithms and autopilot application for an unmanned airvehicle,” M.S. - Master of Science, Middle East Technical University, 2010.