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Advances in Aircraft and Spacecraft Science Volume 6, Number 5, September 2019 , pages 371-389 DOI: https://doi.org/10.12989/aas.2019.6.5.371 |
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Robust H_infinity control applied on a fixed wing unmanned aerial vehicl |
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Caglar Uyulan and Mustafa Tolga Yavuz
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| Abstract | ||
| The implementation of a robust H_infinity Control, which is numerically efficient for uncertain nonlinear dynamics, on longitudinal and lateral autopilots is realised for a quarter scale Piper J3-Cub model accepted as an unmanned aerial vehicle (UAV) under the condition of sensor noise and disturbance effects. The stability and control coefficients of the UAV are evaluated through XFLR5 software, which utilises a vortex lattice method at a pre-defined flight condition. After that, the longitudinal trim point is computed, and the linearization process is performed at this trim point. The \"u-Synthesis\"-based robust H_infinity control algorithm for roll, pitch and yaw displacement autopilots are developed for both longitudinal and lateral linearised nonlinear dynamics. Controller performances, closed-loop frequency responses, nominal and perturbed system responses are obtained under the conditions of disturbance and sensor noise. The simulation results indicate that the proposed control scheme achieves robust performance and guarantees stability under exogenous disturbance and measurement noise effects and model uncertainty. | ||
| Key Words | ||
| aerodynamic; aeroplane equation of motion; flight control; nonlinear control; robust H_infinty control; multi-input multi-output control surface; u-synthesis; unmanned aerial vehicles | ||
| Address | ||
| Caglar Uyulan:Department of Mechatronics Engineering, Bulent Ecevit University, Turkey Mustafa Tolga Yavuz: Department of Aeronautics and Astronautics, Istanbul Technical University, Turkey | ||
