This paper deals with the problem of modelling and controlling an innovative aerial manipulator, i.e. a vertical take-off and landing aircraft equipped with a fully-actuated robotic arm. This system is able to perform complex operations that require the physical interaction with the surrounding environment while remaining airborne. Once a detailed dynamical model in the planar case is provided, a control law able to govern all the degrees of freedom of the system is discussed. Beside the methodological contribution that is easily extendable to different combinations of UAVs and robotic arms, the effectiveness and main properties of the proposed control algorithm are illustrated with the help of an experiment that takes into account the case in which the manipulator is in contact with the surrounding environment.

This work proposes a reactive supervisory control for a team of heterogeneous robots capable of autonomous navigation and cooperation in unstructured and hostile environment. The supervisor is built using classical theories of discrete event systems (DES), but it differs for its reactive capabilities. This allows to have an online evaluation and optimization for dynamic events and environments. The supervisor (high level control) interacts directly with low level control, taking into account dynamic and kinematic of the agents. The specific robotic platform includes both aerial (UAV) and ground robots but the results and applications are absolutely general.

This video presents experiments conducted within the final review meeting demonstration session of the AIRobots project. AIRobots started at 2010 and the final review meeting took place on 22 of March, 2013. The presented experiments cover a wide area of the challenges related with aerial industrial inspection. In particular, multiple test-cases related with both vision-based and contact-based inspection and in general physical interaction are shown. It is highlighted that these experiments were recorded live during the project demonstration and evaluation process.

This paper provides an architectural description from the software point of view of the simulator environment developed for the AIRobots project. The scope of the project is the realization of an aerial service robotic prototype, a sort of robotic hand to be employed in inspection-by-contact tasks. The simulator is then crucial in both the training of the human operator, and as a support tool for the development and validation of low- and high-level control algorithms. The tasks that can be performed are not limited to free-flight missions, but include also to the cases in which the robot has to actively interact with the environment. The simulator relies on Simulink and Blender, and has been designed with a modular structure that makes software-in-the-loop and hardware-in-the-loop simulations possible by simply replacing the different control modules with the real controllers on the prototypes.

This work presents the design and experimental validation of a control strategy for an innovative modular aerial vehicle characterized by redundant actuation. For this class of aircraft, the distinguishing feature of the proposed design - which sets it apart from standard vertical take-off and landing (VTOL) underactuated configurations such as helicopters, ducted-fan tail-sitters or multi-rotors - is that the input redundancy can be employed to improve the dynamical properties of the system. In particular, the vehicle performance can be enhanced in certain applications that benefit from a larger number of degrees of freedom being simultaneously controlled. A control strategy is proposed which is capable of globally stabilizing the dynamics of this class of vehicles along a desired trajectory. The methodology is validated by means of experiments carried out on a special prototype obtained by rigidly connecting two ducted-fan tail-sitter UAVs.

This video shows an innovative over-actuated aerial vehicle specifically designed for tasks requiring high maneuverability such as aerial inspection of infrastructure and aerial manipulation. The main feature of the system is the fact that the redundancy of actuators allows to obtain maneuvers otherwise impossible for other aerial systems such helicopters or quadrotors. The experiments proposed in the video demonstrate how this improved maneuverability can be exploited both during free-flight operations or when physical interaction with the environment is required.

This paper focuses on the modeling and control of a flying robot. The complete system, composed of a quadrotor unmanned aerial vehicle and a custom-made manipulator, has been designed for remote inspection by contact of industrial plants. The goal of this paper is to show the dynamical characteristics of the flying robot during tasks that require physical interaction, and to determine a control strategy that allows to safely interact with unknown environments. The methodology has been implemented on a real prototype and tested in an indoor area. Experimental results validate the proposed controller and show its effectiveness.

This video shows a special prototype of miniature aerial robot, the aerial manipulator, able to accomplish operations requiring the physical interaction with the surrounding environment while remaining completely airborne. The robot arises from the combination of a vertical take-off and landing aircraft, in particular a ducted-fan configuration, and a miniature robotic arm. The physical interaction relies on impedance control considerations. The control law is able to govern all the degrees of freedom of the system both in free-flight and during the interaction with the surrounding environment. In the latter case, the stability of the contact is robustly preserved. The video shows the robotic setup and the effectiveness of the proposed control algorithm in a real-world scenario.

This paper addresses the problem of robust take-off of a quadrotor unmanned aerial vehicle (UAV) in critical scenarios, such as in the presence of sloped terrains and surrounding obstacles. Throughout the maneuver, the vehicle is modeled as a hybrid automaton whose states reflect the different dynamic behaviors exhibited by the UAV. The original take-off problem is then addressed as the problem of tracking suitable reference signals in order to achieve the desired transitions between different hybrid states of the automaton. Reference trajectories and feedback control laws are derived to explicitly account for uncertainties in both the environment and the vehicle dynamics. Simulation results demonstrate the effectiveness of the proposed solution and highlight the advantages with respect to more standard open-loop strategies, especially for cases in which the slope of the terrain renders the take-off maneuver more critical to achieve.

This paper addresses the problem of robust takeoff and landing control of a quadrotor UAV (Unmanned Aerial Vehicle). During the critical flight phases of takeoff and landing the vehicle dynamics change according to the possible existence of contact with the ground. To model the vehicle during the overall maneuver a hybrid automaton is used where each state corresponds to a different dynamic behavior exhibited by the UAV. The original takeoff and landing problems are then addressed as a problem of tracking suitable reference signals in order to achieve the desired transitions between different hybrid states of the automaton. Both reference trajectories and feedback control laws are derived to explicitly account for measurement noise and uncertainties, in both the environment and in the vehicle dynamics. Simulation results demonstrate the effectiveness of the proposed solution.