Differential Flatness and Flatness Inspired Control of Aerial Manipulators based on Lagrangian Reduction
This work addresses control challenges for aerial manipulators, which is an incremental advancement in robotics.
The paper demonstrates that the dynamics of a general class of aerial manipulators, consisting of an underactuated multi-rotor base with an articulated manipulator, are differentially flat, and proposes a quadratic programming-based controller within a Control Lyapunov Function framework, verified in simulation.
This paper shows that the dynamics of a general class of aerial manipulators, consist of an underactuated multi-rotor base with an arbitrary k-linked articulated manipulator, are differentially flat. Methods of Lagrangian Reduction under broken symmetries produce reduced equations of motion whose key variables: center-of-mass linear momentum, vehicle yaw angle, and manipulator relative joint angles become the flat outputs. Utilizing flatness theory and a second-order dynamic extension of the thrust input, we transform the mechanics of aerial manipulators to their equivalent trivial form with a valid relative degree. Using this flatness transformation, a quadratic programming-based controller is proposed within a Control Lyapunov Function (CLF-QP) framework, and its performance is verified in simulation.