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.
This paper describes the tracking guidance for the autonomous UAV landing and the vision-based detection of the marker on the moving vehicle with the real-time image processing system. The detection of the marker is based on the color detection algorithm with morphological filter and the tracking guidance is based on the relative distance between the UAV and the vehicle. In order to track and land...
This article presents an image-based visual servoing system for indoor visual tracking of 3D moving objects by an Unmanned Aerial Vehicle. This system autonomously follows a 3D moving target object, maintaining it with a fixed distance and centered on its image plane. The initial setup is tested in a detailed simulation environment. The system is then validated on flights in indoor scenarios using...
This paper presents a vision-based tracking system for marine surface objects utilizing images captured in a fixed-wing unmanned aerial vehicle (UAV) with a retractable pan/tilt gimbal. A formula for calculating the North-East velocities of objects detected in the images is derived. The formula utilizes optical flow (OF) and compensates for the UAV and gimbal motions. It can be used together with...
In this paper, we present two novel guidance laws for an unmanned aerial vehicle (UAV) equipped with a fixed camera to track a mobile ground target. The system dynamics is established in the level local coordinate frame, removing the need of converting the target location information to the global inertial frame. The first guidance law is developed using backstepping technique requiring the estimation...
(Semi-) autonomous complex UAV missions, such as inspection or search-and-rescue in uncertain dynamic environments, require obstacle avoidance and operator shared control. Combining humans' cognitive abilities with fast automation is the key for such missions. This paper presents a flight control system architecture based on the instantaneous Task Specification using Constraints (iTaSC) methodology...
This paper presents an algorithm for improving navigation performance of an Unmanned Aerial Vehicle (UAV) in GPS-challenging environments, which exploits aiding measurements from one or more cooperative UAVs flying under full GPS coverage. In particular, sensor fusion is based on an Extended Kalman Filter that integrates measurements from onboard inertial sensors and magnetometers, available GPS pseudoranges,...
For flight automation tolerable to satellite navigation dropouts, this paper presents a simultaneous localization and mapping method based on radar altimeter measurements and monocular camera images. The novelty within mapping is the combination of radar distance and image triangulation. This approach verifies whether the radar measurement fits to a specific horizontal plane in the map, yielding the...
An estimation framework is presented that improves the robustness of GPS-denied state estimation to changing environmental conditions by fusing updates from multiple view-based odometry algorithms. This allows the vehicle to utilize a suite of complementary exteroceptive sensors or sensing modalities. By estimating the vehicle states relative to a local coordinate frame collocated with an odometry...
This paper describes a vision-based multiple model adaptive estimation using UAVs that enables the tracking of a mobile target that changes the system model depending on unknown factors. In our system the machine-learning-based target identification method uses Haar-like classifiers that detects the target position. The system uses multiple extended Kalman filters for each system model and estimates...
Visual odometry approaches have demonstrated to work very well for localization in GPS-denied areas, however they could quickly diverge depending on the environment. In order to achieve reliable long-term localization, it is a good practice to complement vision-based estimations with an additional source of information able to correct odometry drifts. This paper presents an approach that complements...
Loading wide baseline multi-arrays optical sensor system enables a UAV to obtain large field of view and multi-view information, and maximize its detection performance. An accurate calibration is a necessary prerequisite. Since the key problem on the calibration of multi-array optical system is how to find the accurate extrinsic parameters of single array, we propose a cooperative calibration with...
This paper addresses the problem of navigating an Unmanned Aerial Vehicle in an environment where GPS quality is degraded or lost. A method is described to return the aircraft from the GPS-degraded region to its launch point by means of visual navigation techniques. We record a string of overlapping images, or keyframes, on the outbound flight. On the return journey, a control law based on the homography...
This paper proposes an autonomous flight control method of quadrotor helicopter using only single Web camera. Recently, great attentions have been paid to the autonomous flight control method of quadrotor helicopter. In the previously proposed methods, for example, GPS, motion capture system and laser range finder are often applied to measure the position and posture of quadrotor helicopter. But,...
Small Unmanned Aerial Systems (sUAS) spread rapidly in the last years, both for civil and military applications. The performance of Dangerous, Dull and Dirty missions implies a wide use of the sUAS, in particular to manage hazardous events, such as natural or manmade major incidents or mass casualty situations. The management and control of an emergency are crucial aspects for the rescue teams and...
In this paper a fast horizon detection algorithm is introduced, which is run on an airborne visual system. It is important to run the horizon detection as fast as possible, and also with low power consumption. Hence we developed an algorithm, which has low complexity. The horizon detection uses attitude information provided by the flight control computer of the aircraft and it corrects the horizon...
In a search and rescue scenario, an expeditious response is critical since the radius of the search area increases by roughly 3 km per hour while the life expectancy of the lost individual decreases. To find the object of the search as quickly as possible, the incident commander creates an overlay probability map identifying high priority search areas and develops a search plan that allocates search...
As small unmanned aircraft systems become increasingly affordable, reliable, and formally recognized under federal regulation, they become increasingly attractive as novel platforms for civil applications. This paper details the development and demonstration of both fixed-wing and rotorcraft-based unmanned systems for infrastructure assessment tasks. Tasks such as inspecting pavement condition and...
Personal drones are becoming part of every day life. To fully integrate them into society, it is crucial to design safe and intuitive ways to interact with these aerial systems. The recent advances on User-Centered Design (UCD) applied to Natural User Interfaces (NUIs) intend to make use of human innate features, such as speech, gestures and vision to interact with technology in the way humans would...
The Intelligent Tasker was developed to provide dynamic retasking of autonomous coordinated aerial assets to accommodate “pop-up” points of interest and the loss of a team member during a coordinated mission. The system was implemented in MATLAB and can be integrated with various ground stations. The user interface and backend GA Optimizer make planning and executing an optimized coordinated mission...
An optimal design method for generating a flight path passing through specified waypoints while satisfying the task points sent by the ground operators is proposed in this paper. Each specified waypoint is reached exactly at the specified location and time while intermediate waypoints are generated in such a way that they satisfy the task points, with highest benefit measure, i.e., satisfying tasks...
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.