Terrain aided navigation

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2010
Karabörk, Alper
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An Inertial Navigation System (INS) can individually produce the navigation data, i.e.position, velocity, of the aircraft without any help or aid. However, a large number of errors are ntroduced by sensors causing to an unacceptable drift in the output. Because of this reason, external aids are used to correct INS. Using these aids an integrated navigation structure is developed. In an integrated navigation system, INS output is used to alculate current navigation states; aid is used to supply external measurements and di erent algorithms are used to provide the most probable corrections to the state estimate using all data. One of the integrated navigation approaches is Terrain Aided Navigation (TAN). Terrain Aided Navigation is a technique to estimate the position of a moving vehicle by comparing the measured terrain profile under the vehicle to a stored map, DTED. This thesis describes the theoretical aspects implementation of a simulation environment, simulations of the implemented Kalman Filtering TAN algorithms with developed INS model. In order to perform the study, first a thorough survey of the literature on TAN navigation algorithms is performed. Then, we have developed a dynamics simulation environment. A flight profile generator is designed. Since, the main issue of this work is to correct INS, an Strapdown INS model developed using Matlab INS Toolbox. Therefore, to model a Strapdown INS, mathematical equations of INS system are derived and they are linearized to form linear error model. In addition, a radar altimeter simulator is also developed that provides measurement to the error dynamics. Then, a Kalman filter structure is designed and implemented using Matlab. The simulations are done with di erent linearization approaches using Kalman filter structure. Finally, the performance of the implemented algorithms are evaluated.
Geographic information systems., Mobile robots., Location-based services., Electrical Engineering.
http://etd.lib.metu.edu.tr/upload/12612493/index.pdf
https://hdl.handle.net/11511/20104
Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats
A. Karabörk, “Terrain aided navigation,” M.S. - Master of Science, Middle East Technical University, 2010.
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