Task priority control for aerial manipulation

This paper presents a task oriented control strategy for aerial vehicles equipped with a manipulator. A camera is attached to the end-effector of the manipulator to perform a primary task consisting on visual servoing towards a desired target. Over-actuation of the whole quadrotor-arm system is exploited to achieve secondary velocity tasks. One subtask is proposed to horizontally stabilize the platform during flight by aligning the arm center of gravity with the quadrotor gravitational vector. The arm singularities and manipulability are addressed by another subtask that leads the arm to a preferable configuration, and also takes into account the arm joint limits. The performance of the whole visual servo and secondary tasks control scheme is shown in a Robot Operating System (ROS) implementation.