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This paper addresses the problem of autonomous navigation of a quadrotor helicopter using state estimators when the GPS signal is not available. The main objective is to estimate the translational position and velocity of the flying machine. The observer proposed uses a double integral approximation of the acceleration defined in the mathematical model in order to estimate the states previously mentioned...
Despite being unmatched on the battlefield or at home, low-cost, asymmetric threats have proven dangerous for U.S. military forces and homeland security. The proliferation of improvised explosive devices of all types in the Iraqi and Afghan theaters has demonstrated that inexpensive, commercial off-the-shelf technology and some electronics knowledge can be combined to significantly impact high-tech...
This paper presents an implementation method for an autonomous take-off and landing with a quadcopter on a stationary platform. The altitude measurement is improved with a Lidar, an inertial unit and a Kalman filter. Equations shown for a take-off and landing path use position and velocity commands. A non linear Backsteping robust control law is used. The entire system is programmed in C/C++ with...
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,...
Unmanned aerial vehicles (UAVs) are widely applied in both civil and military fields, such as rescue, surveillance, exploration, navigation, precision agriculture and etc., because of small size, low cost and easy maintenance. However the autonomous flight of UAVs under unstructured environment is still open, especially when GPS is unavailable or indoor task is scheduled. Furthermore, GPS-based navigation...
The increasing civilian demand for autonomous aerial vehicle in the professional markets led to an abundance of inexpensive navigational hardware platforms and vehicle prototypes. Current photogrammetry-based applications require crisp and precise positioning of images so that the process does not fails. Also systems adaptable to the circumstances for better effectiveness, vehicles capable of vertical...
Success of a cooperative mission entirely depends on precise navigation information of each UAV. Though present day UAVs are equipped with GPS, the UAVs have to rely only on navigation information obtained from inertial navigation system while operating in GPS denied environments. This research work, addresses the problem of establishing a GPS protected wireless MAV network (WIMAN) using three classes...
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,...
This paper examines the capability of a miniaturized radar sensor developed for micro Unmanned Aerial Systems (UAS) to assist the flying platform with autonomous navigation, sense-and-avoid (SAA), and imaging functions. An ultralight radar sensor based on Frequency Modulated Continuous Wave (FMCW) technology and developed by IMST GmbH is tested and results of acquired data for navigation, SAA, and...
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...
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