This paper presents the design of 3-Dof multi-link robot arm that is mounted on the multirotor. To be considered the dynamic characteristics of the manipulation platform, the decoupled dynamic models of the system are derived. The main advantage of the first joint is introduced for more robustness and stability during hovering. The PID controller will be implemented for position and attitude of multirotor control, whereas, a sliding mode controller will be designed for a manipulator robot, which is then compared with the sliding surface that has been integrated with the proportional-derivative (PD) controller. The performance of the proposed technique is demonstrated through a simulation using Simulink and Matlab environment.

This paper presents the design and modelling of a new Aerial manipulating system, that resolve a displacement of centre of gravity of the whole system with a mechanical device. A prismatic joint between the multirotor and a robotic arm is introduced to make a centre of mass as close as to the geometric centre of the whole system. This paper details also the geometric and dynamic modelling of a coupled system with a Lagrange formalism and control law with a Closed Loop Inverse Kinematic Algorithm (CLIKA). This dynamic inverse control is validated in a Simulink environment showing the efficiency of our approach.

In this paper, we develop an analytic methodology to determine the best technology to carry the communication between an Unmanned Aerial Vehicle (UAV) and a ground control station (GCS). We assume herein that the UAV is performing its mission under nominal conditions. For this, we identify some relevant criteria that cover most use-cases. We propose a multi-criteria analysis to determine the best technology to carry the radio- communication between the UAV and the GCS. In this work, we distinguish between the Control and Non- Payload Communication Channel (CNPC) and the Payload Channel. By studying two different missions, we emphasize that the technology assessment results depend on the use-case as well as the UAV scenario, and that for a same scenario the results for CNPC are different from the Payload communication. In this work, we are focused on the precise agriculture (PA) use-case, and the public safety (PS) use case. We present the assessment results in both Visual Line of Sight (VLOS), and Beyond Line of Sight (BVLOS) scenarios. The latter is very interesting because the communication UAV - GCS becomes of critical importance.

In this paper, two redundant controllers are proposed in order to boost the capabilities of the popular feedback linearization flight controller scheme. The first one is based on the sliding mode framework whilst the second one is built upon the Model Free Control (MFC) theory. An in-depth discussion is highlighted with detailed evaluation in terms of performance, consumed energy, and robustness by considering several scenarios and using several metrics. The numerical simulations have shown satisfactory results using nominal system model or disturbed model through an application to a small Vertical Take-Off and Landing (VTOL) quadrotor.

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In this paper, a quadrotor optimal coverage planning approach in damaged area is considered. The quadrotor is assumed to visit a set of reachable points following the shortest path while avoiding the no-fly zones. The problem is solved by using a two-scale proposed algorithm. In the first scale, an efficient tool for cluttered environments based on optimal Rapidly-exploring Random Trees (RRT) approach, called multi-RRT* Fixed Node (RRT*FN), is developed to define the shortest paths from each point to their neighbors. Using the pair-wise costs between points provided by the first-scale algorithm, in the second scale, the overall shortest path is obtained by solving the Traveling Salesman Problem (TSP) using Genetic Algorithms (GA). Taking into consideration the limited onboard energy, a second alternative based on the well-known Vehicle Routing Problem (VRP) is used. This latter is solved using the savings heuristic approach. The effectiveness of this proposed two-scale algorithm is demonstrated through numerical simulations and promising results are obtained.

This paper presents an algorithm for aerial vehicle trajectory generation based on the optimal Rapidly-exploring Random Tree (RRT*). The trajectory generation for the aerial vehicle is a complex path planning problem since the vehicle flies in a heterogeneous environment. The vehicle must also avoid some obstacles or inaccessible zones such as buildings, mountains and even radar detection zones depending on the mission. The RRT* algorithm is used as a basis to find near-optimal solutions for this problem. The shortest Dubins' path in heterogeneous environment is used to compute a distance and a trajectory between two vehicle states. Simulated results show the capability of the algorithm to find a feasible near-optimal trajectory in terms of path length that anticipates future flight conditions, such as the decrease in maneuverability in high altitude. The results also show the advantages over the numerical methods in avoiding obstacles.

This paper addresses the problem of time optimal path planning for a quadrotor helicopter evolving in a region of known winds. Usually, the flight control of quadrotors subject to wind disturbances challenge seeks to find the optimal control to keep track of a desired trajectory in a windy region. This approach has one major disadvantage: the quadrotor flight control has to compensate for trajectory deviations; therefore, the energy consumption becomes an issue. Most unmanned aerial vehicles (UAV) navigation techniques use waypoints to accomplish their missions. In the framework of a waypoint based navigation, a promising path planning strategy would be a time optimal approach in which the UAV would take advantage of wind to reach its next waypoint; therefore, saving time and energy (under constant forward velocity constraint). A model separation is used to simplify the control of the six-degrees-of-freedom (6DOF) dynamics of the quadrotor. Such approach allows to deal with quadrotor's 3D-motion through two subsystems: dynamic (altitude and MAV-relative forward velocity) and kinematic (nonholonomic navigation) subsystems. In terms of control, a hierarchical control scheme is used to stabilize dynamic and kinematic underactuated subsystems involved in the navigation task. The time optimal path planning is computed using a dynamic optimization method for continuous systems with some state variables specified at an unspecified terminal time. Results have been validated in simulation.

This paper presents missile guidance as a complex robotic problem: a hybrid non-linear system moving in a heterogeneous environment. The proposed solution to this problem combines a sampling-based path planner, Dubins' curves and a locally-optimal guidance law. This algorithm aims to find feasible trajectories that anticipate future flight conditions, especially the loss of manoeuverability at high altitude. Simulated results demonstrate the substantial performance improvements over classical midcourse guidance laws and the benefits of using such methods, well-known in robotics, in the missile guidance field of research.

In this paper, we study the trajectory tracking problem of autonomous small airplanes in presence of unknown wind gusts. The vehicle is represented by its center of gravity, and the mathematical translational model is derived using Newton's second law. The controller is designed using Robust Control Lyapunov Function and Sontag's feedback stabilizing universal. The proposed control laws guarantees, by structure, the robustness of the system with respect to different uncertainties due to model and unknown external parameters. Numerical simulations are performed to demonstrate the performance of proposed control strategy.

In this paper we propose an algorithm allowing the calculation of the trim trajectories for the airship. These trajectories are suitable for control, by linearizing the dynamic equations around the trim conditions, and hence simplifying significantly the controller synthesis. Another advantage related to trim trajectories consists in the simplification of the development of the aerodynamic parameters estimation algorithms. To ensure trim feasibility, a set of constraint relating to the dynamic equations of the airship, actuator saturation and other type of constraints are taken into account

The objective of this paper is to generate a desired flight path to be followed by an autonomous airship. The space is supposed without obstacles. As there is six degrees of freedom and only three inputs for the LSC airship in a low velocity flight, three equality constraints appear due to the under-actuation. When the roll φ and pitch θangles θangles θangles θangles θangles θangles θangles as well as the longitudinal velocity u are imposed, the first constraint gives a differential equation on the yaw angle ψ, ψ, the second equality gives a differential equation on the lateral velocity v and the third one an equation on the vertical velocity w.

Motion generation gives the joint positions speeds and accelerations of manipulators, at every moment. We assume that the motion are polynomial trajectories, that ensure joint acceleration continuity Usual kinematical constraints, obtained with approximations, are not always sufficient, then we will focus on actuators constraints on voltages and currents.

The optimal motion generation problem is solved subject to various actuator constraints while the motion is constrained to an arbitrary path. The considered objective function is a weighted time energy function while most of existing methods consider only the time-optimal problem. We present some simulation results using a mathematical programming technique (sequential quadratic programming) existing in the NPSOL software.