The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this paper, we explore the UAV loss detection and auto-replacement scheme in a multi UAV system. The developed scheme is based on the concept of cooperative multi UAV control, where the cooperation is achieved by broadcasting heartbeats (HBs) and information fusion technology. We first propose the UAV loss detection method by checking the HB time. Subsequently, we present the UAV auto-replacement...
In this paper, we address the Dubins Orienteering Problem with Neighborhoods (DOPN) a novel problem derived from the regular Orienteering Problem (OP). In the OP, one tries to find a maximal reward collecting path through a subset of given target locations, each with associated reward, such that the resulting path length does not exceed the specified travel budget. The Dubins Orienteering Problem...
This paper proposes a fuzzy adaptive sliding mode control for accommodating large actuator fault and maintaining system stability. Boundary layer is employed to smooth control discontinuity and eliminate control chattering. However, if the thickness of boundary layer is chosen too big, the tracking accuracy will be degraded. Whereas, if the boundary layer thickness is too small, control chattering...
In swarm robotics, the self-organization of multiagent systems which consists of a number of comparatively simple agents is an approach inspired from natural swarms. In this paper, we solve the findpath problem of n ε N agents using the principle of swarming. A Lagrangian swarm model which could navigate in a cluttered configuration space is developed. A Lyapunov like function is constructed from...
This paper is focused on the analysis and comparison of different data structures for 3D space representation in autonomous exploration of large marine structures with UAS. The classical and widely used frontier exploration approach is applied: the frontier cells, which are the locations in the world representation map that are explored and unoccupied but has unexplored space in its vicinity, are...
This paper presents a nonlinear model predictive controller to follow desired 3D trajectories with the end effector of an unmanned aerial manipulator (i.e., a multirotor with a serial arm attached). To the knowledge of the authors, this is the first time that such controller runs online and on board a limited computational unit to drive a kinematically augmented aerial vehicle. Besides the trajectory...
Development of complex multi-robot systems requires time-consuming and expensive testing and, especially in a case of unmanned aerial systems, it aggregates risk of hardware failures and legal issues when operating more than one unmanned aircraft simultaneously. It is highly favorable to deal with most of the eventual design flaws and system bugs before the final field tests in a simulation where...
In this paper, the pitch control of a miniature unmanned airship using a sliding ballast is presented. The sliding ballast design has been developed to address the limited altitude maneuverability of lighter-than-air vehicles by allowing for large changes in vehicle pitch and, when combined with forward facing thrusters, rapid changes in altitude. Using the longitudinal position of the ballast as...
In this paper, we implement an advanced modelfree PID controller for a DJI F450 quadcopter which is controlled and stabilized by a non-rooted onboard Android smartphone, without the aid of an external IMU. Furthermore, since Android is not a realtime system, the control commands and sensor measurements are subject to significant latencies, and hence the PID controller is modified to account for non-trivial...
A controller is designed for hexacopter platform to achieve accurate tracking of altitude and attitude commands under the influence of severe disturbances. The main aim is designing a controller that can be tuned easily to satisfy desired performance requirements. For this purpose, multi-variable control method LQR is combined with PID structure which provides valuable physical insight in tuning process...
One of the major challenges of conducting operation of unmanned aircraft, especially operations beyond visual line-of-sight (BVLOS), is to make a realistic and effective risk assessment. An important part of such an assessment is to identify the risk of fatalities, preferably in a quantitative way since this allows for comparison with manned aviation to determine whether an equivalent level of safety...
To address the problem of fault detection and diagnosis of an unmanned quadrotor helicopter (Qball-X4) in the presence of actuator faults, this paper presents a fault diagnosis method based on particle filter. The fault detection and state estimation based on the particle filter are used to control the altitude of the Qball-X4 with integration of a Linear Quadratic (LQ) technique. In the platform...
This paper deals with the problem of robust output regulation for a set of Quad-Rotors forming a geometric pattern. The proposed control strategy is based on sliding- modes techniques, and it is able to robustly regulate the corresponding Quad-Rotors positions and angles in the presence of some class of disturbances acting on the Quad-Rotors. The proposed regulation is composed by cascaded continuous...
The objective of this paper is to demonstrate the application of optimal control for generating dynamically constrained minimal time trajectories in micro unmanned airships. By design, airships are generally underactuated and underpowered limiting their maneuvering capabilities. Using a simplified dynamic model derived with experimentally derived coefficients, two trajectory planning simulations are...
This paper proposes the concept of drones capable of functioning as “Co-Archaeologists” that can map large caves and enter dangerous or hard-to-reach spaces. Using RGB-D data collected by drones, we will be able to produce accurate 3D models and semantic maps with proper lighting co-supervised by human archaeologists. This is going to be a major advance in archaeological practice, which can accelerate...
The paper reports on the energy consumption of smooth trajectories for stop-and-go navigation of aerial robots. We consider a decimeter-scale quadrotor tasked to travel on straight line, constant height trajectories from an initial hover configuration to another hover configuration. We investigate three prominent types of smooth trajectories (minimum acceleration, minimum jerk and minimum snap), and...
In this paper we calculate probabilistic estimates for the size of an area a single unmanned aerial vehicle (UAV) can expect to monitor when tracking multiple objects. The objects are assumed to move according to a linear velocity model with Gaussian process noise. We use a Kalman filter to estimate the position of the objects. By using the covariance matrix of the Kalman filter, we can derive the...
Autonomous navigation of small Unmanned Aerial Vehicles (UAVs) in cluttered environments is still a challenging problem. In this work, we present an approach based on graph slam and loop closure detection for online mapping of unknown outdoor environments using a small UAV. Here, we used an onboard front facing stereo camera as the primary sensor. The data extracted by the cameras are used by the...
In this paper, we present the design and verification of a hybrid vertical takeoff and landing (VTOL) unmanned aerial vehicles (UAV) of the type named dualsystem or extra propulsion VTOL UAV. This paper features the comprehensive system development of such VTOL UAVs from all aspects, including the aircraft design and implementation, onboard devices integration, ground station support, and long distance...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.