【摘 要】
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This paper investigates the precise trajectory tracking of unmanned aerial vehicles(UAV)capable of vertical take-off and landing(VTOL)subjected to external disturbances.For this reason,a robust higher-order-observer-based dynamic sliding mode con-troller(
【机 构】
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Department of Applied Science,School of Computing,Engineering and Built Environment,Glasgow Caledoni
论文部分内容阅读
This paper investigates the precise trajectory tracking of unmanned aerial vehicles(UAV)capable of vertical take-off and landing(VTOL)subjected to external disturbances.For this reason,a robust higher-order-observer-based dynamic sliding mode con-troller(HOB-DSMC)is developed and optimized using the fractional-order firefly algorithm(FOFA).In the proposed scheme,the slid-ing surface is defined as a function of output variables,and the higher-order observer is utilized to estimate the unmeasured variables,which effectively alleviate the undesirable effects of the chattering phenomenon.A neighboring point close to the sliding surface is con-sidered,and as the tracking error approaches this point,the second control is activated to reduce the control input.The stability analys-is of the closed-loop system is studied based on Lyapunov stability theorem.For a better study of the proposed scheme,various traject-ory tracking tests are provided,where accurate tracking and strong robustness can be simultaneously ensured.Comparative simulation results validate the proposed control strategy\'s effectiveness and its superiorities over conventional sliding mode controller(SMC)and integral SMC approaches.
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