Design of an automatic landing system using linear quadratic tracker.

• Autor(a) principal: Fabrício Reis Caldeira
• Data de Publicação: 2008
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações do ITA
• Texto Completo: http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=725
• topic: Controle automático de aterrissagem; Controladores; Regulador linear quadrático; Sistemas de aterrissagem por instrumentos; Método de Monte Carlo; Simulação; Controle; Engenharia aeronáutica

This work presents the application of the Linear Quadratic Tracker (LQT) for the automatic landing system of passenger transport airplanes. The design method to achieve an autoland flare law with improved performance and disturbance rejection is described. With this method the design is direct and more formal thus avoiding the somewhat time consuming and more ad-hoc design iterations currently practice in industry. Although the design technique has been used for a autoland system, the approach is general enough to be used in other control applications. The structure of a traditional flare controller used for transport airplane and the LQT flare controller are presented. The performance of the flare control law designed based on LQT is compared against the performance of a traditional flare control law. Simulation time histories and Monte Carlo simulation results are presented. The time histories simulations cover the nominal and the most adverse conditions anticipated during the operation of the autoland system. The results show that the LQT law provides a more accurate path control and better disturbance rejection. The Monte Carlo simulation was made according to the certification requirements of an autoland system. The results show that the LQT controller provides reduced touchdown dispersion for the sink rate and distance at touchdown. The automatic landing system using LQT complies easily with the certification requirements, whereas the traditional system based on the classical design of autopilot inner loop/outer loop meets the certification requirements with smaller margins.