In this article, we propose a control solution for the safe transfer of a quadrotor UAV between two surface robots positioning itself only using the visual features on the surface robots, which enforces safety constraints for precise landing and visual locking, in the presence of modeling uncertainties and external disturbances. The controller handles the ascending and descending phases of the navigation using a visual locking control barrier function (VCBF) and a parametrizable switching descending CBF (DCBF) respectively, eliminating the need for an external planner. The control scheme has a backstepping approach for the position controller with the CBF filter acting on the position kinematics to produce a filtered virtual velocity control input, which is tracked by an adaptive controller to overcome modeling uncertainties and external disturbances. The experimental validation is carried out with a UAV that navigates from the base to the target using an RGB camera.

翻译：本文提出一种控制解决方案，用于四旋翼无人机在仅利用地面机器人视觉特征的情况下，在两个地面机器人之间实现安全转移。该方案在存在建模不确定性和外部干扰时，强制执行精确着陆与视觉锁定所需的安全约束条件。控制器分别采用视觉锁定控制屏障函数(VCBF)和可参数化切换下降CBF(DCBF)处理导航的上升与下降阶段，无需外部规划器。该控制方案采用反步法设计位置控制器，并通过CBF滤波器作用于位置运动学，生成滤波后的虚拟速度控制输入，由自适应控制器进行跟踪以克服建模不确定性与外部干扰。实验验证通过搭载RGB摄像头的无人机从基地导航至目标的过程完成。