Summary: | In this paper, we present an attitude restricted dynamic surface (DSC) controller for the vision-based quadrotor to ensure that visual target remains in the camera's field of view all the time. To ensure stable quadrotor motion, proper perspective image moments are first extracted from the defined virtual image plane to derive the decoupled vision-quadrotor dynamics. Then, by developing a novel saturated DSC controller to limit the roll and pitch commands and employing an integral barrier Lyapunov function to guarantee the boundness of attitude responses, an attitude restricted DSC controller is devised under a backstepping framework for quadrotors. The designed control scheme can regulate the moment features to their desired values without the violation of visibility constraint with both the attitude inputs and responses of quadrotor keeping inside the predefined state space. The boundedness and convergence of the closed-loop system are proved by the Lyapunov theory. Then, the satisfaction of the pre-specified constraints on the roll and pitch states can be guaranteed. The effectiveness and superiority of the proposed method are validated through extensive simulations and comparisons.
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