Fixed-time Fractional-order Sliding Mode Control for Image-based Visual Servoing of Hexarotor

This paper introduces a fixed-time fractional order sliding mode control (FTFOSMC) strategy designed for visual servoing applications using a hexarotor. In contrast to traditional finite-time sliding mode control approaches, the proposed method ensures the convergence of error trajectories to zero within a precisely defined time frame, irrespective of the system's initial conditions. The incorporation of fractional calculus in the control design minimizes chattering in the control effort, enhancing the strategy's suitability for realtime applications. The efficacy of the FTFOSMC strategy is demonstrated by integrating it with an image-based visual servoing approach on a hexarotor. Despite the nonlinear dynamics of the hexarotor and uncertainties introduced by the image node, the proposed controller effectively mitigates inherent chattering, achieving error convergence to zero within a fixed time based on fixed-time Lyapunov's stability theory. The paper further substantiates the superior performance of the proposed controller through a static platform landing task using AruCo markers, including a comparison with the existing finite-time sliding mode control strategy. The results affirm the effectiveness of the FTFOSMC approach and its potential to enhance the performance of hexarotor-based visual servoing applications in real-world scenarios.