Download or read book Real Time Navigation and Flight Path Generation for Tracking Stop and Go Targets with Miniature Air Vehicles written by and published by . This book was released on 2008 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research effort focuses on using a heuristic approach to determine the optimal flight path required to put an Unmanned Aircraft System's (UAS) sensor on a moving target in the presence of a constant wind field. This thesis builds on past work using dynamic optimization techniques to calculate minimum time to target. The computationally intensive dynamic optimization routines in their current form take a prohibitive amount of time to calculate and ultimately result in erroneous flight path predictions due to inherent execution time latencies. Therefore an iterative, suboptimal heuristic approach was explored to mitigate excessive calculation times and ultimately yield improved flight path predictions. This report not only explores the heuristic techniques used for flight path calculation, but also includes real world application and flight test results in a Micro Air Vehicle equipped with an autopilot.
Download or read book Real time Flight Path Optimization for Tracking Stop and go Targets with Micro Air Vehicles written by Nate A. Terning and published by . This book was released on 2008 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Real Time Trajectory Generation for Autonomous Nonlinear Flight Systems written by and published by . This book was released on 2006 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unmanned aerial vehicle and smart munition systems need robust, real-time path generation and guidance systems to avoid terrain obstructions, navigate in hazardous weather conditions, and react to mobile threats such as radar, jammers, and unfriendly aircraft. In Phase 1 of this STTR project, real-time path planning and trajectory generation techniques for two dimensional flight were developed and demonstrated in software simulation. In Phase 2 these algorithms were refined, extended and were demonstrated in flight on a unique low-cost micro-air vehicle with a payload which included three optical flow sensors, a laser ranger, and a video camera. This report is a comprehensive technical summary of the significant work completed in Phase 2 to enable development of autonomous flight control systems which are capable of accomplishing the complex task of path and trajectory planning in dynamic and uncertain environments.
Download or read book Real time Trajectory Generation for Target Localization Using Micro Air Vehicles written by Jeffrey B. Corbets and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tracking and Navigation Methods for Unmanned Aerial Vehicles written by Sarjit Goswami and published by . This book was released on 2012 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: This project deals with tracking and navigation methods for Unmanned Aerial Vehicles (UAVs). Tracking, navigation, and online flight path control are essential for any application employing UAVs. Issues such as optimal flight path and obstacle avoidance are also important for the deployment of UAVs in real world applications. This project employs plane decomposition and kinematics-based rules to derive linear navigation control laws. These control laws depend on navigation parameters such as proportionality and deviation factors used to guide the UAV to successfully reach a moving goal following a non linear path. Two modes of UAV motion are presented in the project: 1) Surveillance mode in which a UAV follows a moving goal in a three dimensional space and eventually reaches it with the help of the navigation law. 2) Obstacle avoidance mode in which the UAV maneuvers around the obstacles in its flight path and reaches the moving goal with the help of the navigation law. Through simulation, it is shown that the navigation laws used in this project derived based on kinematics rules are adequate for successful implementation of the tracking and navigation of the UAV, allowing the vehicle to reach an arbitrary goal moving with nonlinear maneuvers.
Download or read book Real Time Tracking of the Path of a Smart Flying Object written by Umair Muhammad Arif and published by LAP Lambert Academic Publishing. This book was released on 2011-07 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tracking System has great importance in intelligent system and has a wide scope. Enormous researches are going to make such systems that are more reliable and accurate. The theory of our project is to trace the path of a smart flying object. Therefore, in order to trace the flying path, we will be using high speed CCTV cameras interfaced with PC and captures the real time video of the flying object and continuously transmit to the PC where video is processed for recognition in MATLAB s image processing tool box. After image processing, the centroid of the object is plotted. This plot will be used to target and lock the motors circuitry to that object. The path followed by a smart flying object (For e.g. A Bee) during its normal flight is probabilistically random. A bee can take any place in the 3-D space which is not deterministic by an independent observer at all. The main theme of the project is to track the real time movement of the object using Image Processing Techniques as a tool for recognition of that object which in turn will be used to target and lock the camera to that object.
Download or read book Bulletin of the Atomic Scientists written by and published by . This book was released on 1961-05 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Bulletin of the Atomic Scientists is the premier public resource on scientific and technological developments that impact global security. Founded by Manhattan Project Scientists, the Bulletin's iconic "Doomsday Clock" stimulates solutions for a safer world.
Download or read book Optimal Wind Corrected Flight Path Planning for Autonomous Micro Air Vehicles written by Michael D. Zollars and published by . This book was released on 2007 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nonlinear Estimation for Vision based Air to air Tracking written by Seung-Min Oh and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Unmanned aerial vehicles (UAV's) have been the focus of significant research interest in both military and commercial areas since they have a variety of practical applications including reconnaissance, surveillance, target acquisition, search and rescue, patrolling, real-time monitoring, and mapping, to name a few. To increase the autonomy and the capability of these UAV's and thus to reduce the workload of human operators, typical autonomous UAV's are usually equipped with both a navigation system and a tracking system. The navigation system provides high-rate ownship states (typically ownship inertial position, inertial velocity, and attitude) that are directly used in the autopilot system, and the tracking system provides low-rate target tracking states (typically target relative position and velocity with respect to the ownship). Target states in the global frame can be obtained by adding the ownship states and the target tracking states. The data estimated from this combination of the navigation system and the tracking system provide key information for the design of most UAV guidance laws, control command generation, trajectory generation, and path planning.
Download or read book Robust Tracking of Dynamic Targets with Aerial Vehicles Using Quaternion based Techniques written by Hernán Abaunza Gonzalez and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this thesis work is to design control and navigation algorithms for tracking of dynamic ground targets using aerial vehicles. Quaternions, which provide an alternative to the classical representations of aerial vehicle dynamics, have been chosen as a basement to develop robust controllers and agile navigation algorithm, due to their advantages such as the absence of singularities and discontinuities and their mathematical simplicity when handling rotations. The quaternion-based control approaches explored in this thesis range from state feedback, passivity, and energy-based controllers, up to sliding modes, and three-dimensional saturation approaches. Then, autonomous and semi-autonomous navigation strategies for quadrotors were explored. An algorithm has been developed for controlling a quadrotor using gestures from a user wearing an armband. To facilitate the operation of multirotors in adverse scenarios, an aggressive deployment strategy has been proposed where a quadrotor is launched by hand With its motors turned off. Finally, autonomous navigation techniques for tracking dynamic targets have been designed. A trajectory generation algorithm based on differential equations has been introduced to track a land vehicle while describing circles. Finally a distributed path planning algorithm has been developed for a fleet of drones to autonomously track ground targets by solving an online optimization problem.
Download or read book Real time Implementation of an Asynchronous Vision based Target Tracking System in an Unmanned Aerial Vehicle written by and published by . This book was released on 2007 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: Currently, small unmanned aerial vehicles developed by NPS have been able to locate and track stationary and moving targets on the ground. New methods of continuous target tracking are always being developed to improve speed and accuracy, ultimately aiding the user of the system. This thesis describes one such method, utilizing an open loop filter as well as an external correction source: Perspective View Nascent Technologies (PVNT). While the PVNT correction can theoretically improve the accuracy from 20-30 meters to 1-2 meters, it does have a disadvantage in that the target position updates are delayed anywhere from 1-10 seconds. In order to account for the delay, an asynchronous filter is used to update the target position data given the external position correction from PVNT. Two cases have been tested including the general filter and one that utilizes a road model in the calculations. While an earlier thesis developed the basic simulation for the system, this thesis discusses improvements and corrections to the simulation model as well as the necessary steps for real-time implementation.
Download or read book Tracking of Ground Mobile Targets by Quandrotor Unmanned Aerial Vehicles written by Ruoyu Tan and published by . This book was released on 2013 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: An Unmanned Air Vehicle (UAV) is an aircraft without a human pilot on board. It can be controlled either autonomously by computers onboard, or using a remote control by a pilot on the ground, or in another vehicle. In both military and civilian sectors, UAVs are quickly obtaining popularity and expected to expand dramatically in the years to come. As UAVs gain more attention, one of the immediate requirements would be to have UAVs work as much autonomously as possible. One of the common tasks that UAVs would be engaged in is target tracking which has various potential applications in military field, law-enforcement, wildlife protection effort, and so on. This thesis focuses on development of a controller for UAVs to track ground target. In particular, this thesis focuses on quadrotor UAV, which is a multicopter that is lifted and propelled using four motors. Admittedly, several target tracking control methods have been developed in recent years. However, only a few of them have been applied on a quadrotor. Most of these tracking methods, particularly those based on Proportional Derivative (PD) control laws, which have been applied on quadrotors, are not time efficient due to practical acceleration constraint and a number of parameters that need to be tuned. The UAV control problem can be divided into 4 sub-problems: Position Control, Motor Control, Trajectory Tracking and Trajectory Generation. In this thesis, the dynamic equations of motion for quadrotors and a Proportional Derivative control law is derived to solve the problems of Position Control, Motor Control and Trajectory Tracking. A Proportional Navigation (PN) based switching strategy is proposed to address the problem of Trajectory Generation. The experiments and numerical simulations are performed using non-maneuvering and maneuvering targets. The simulation results show that the proposed PN based switching strategy not only carries out effective tracking but also results into smaller oscillations and errors when compared to the widely used PD tracking method. The switching strategy, as proposed as a solution to target tracking problem, leaves an important question with regard to when should the switching happen. It is intuitive that the time of switching will play a role in how fast the UAV converges to the target. The second problem considered in this thesis relates to the optimal time of switching that would minimize the positional error between the UAV and the target. An optimal switching strategy is proposed to obtain the optimal switching time for both non-maneuvering and maneuvering targets. Analytical solutions that generate trajectories based on PN and PD methods are used in this strategy. The numerical simulations validate the optimality, reliability, and accuracy of the proposed method for both non-maneuvering and maneuvering targets.
Download or read book Flying Magazine written by and published by . This book was released on 2006-03 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Extensions to the Probabilistic Multi hypothesis Tracker for Tracking Navigation and SLAM written by Brian Cheung and published by . This book was released on 2012 with total page 149 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-target tracking is a problem that involves estimating target states from noisy data whilst simultaneously deciding which measurement was produced by each target. The Probabilistic Multi-Hypothesis Tracker (PMHT) is an algorithm that solves the multi-target tracking problem. This thesis presents extensions to the PMHT to address problems that may arise in the use of real sensors and considers multi-target tracking techniques for use in other applications such as autonomous vehicles. It is generally assumed that a sensor collects a set of noisy position measurements at known times. In some situations, the time information may not be reliable and cause filtering issues. This thesis derives an extension to the PMHT that introduces an assignment index that identifies the true time at which a measurement was collected. This extension of the PMHT allows for tracking on measurements with time errors, such as time delays. A further extension allows the PMHT algorithm to simultaneously estimate the time error parameters whilst tracking targets. The above extension is applied to the problem of planning paths for multiple platforms to explore an unknown area. Given a set of locales to be visited and the platform initial positions, the path planning problem has the same mathematical form as a multi-target tracking problem, with locales as measurements and the platforms as targets. The extended PMHT algorithm uses hypothesised time-stamps to associate locales to platforms and times simultaneously. Autonomous vehicles are expected to use information from their sensors to navigate and map their environment. Simultaneous localisation and mapping (SLAM) is the name given to this task and is essentially a multi-target tracking problem. This thesis proposes the use of PMHT and landmark classification information received with measurements to improve the performance of SLAM.
Download or read book M thode de formation pour les m tiers urbains ou ruraux Institut national de formation des cadres professionnels Minist re du travail et de la s curit sociale et centre national de la recherche scientifique S rie Fol Nouveau tirage written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Real time Optimal Trajectory Smoothing for Unmanned Aerial Vehicle in Three Dimensions written by Saideepthi Malisetty and published by . This book was released on 2011 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents a dynamically feasible and real-time trajectory path generation algorithm for unmanned aerial vehicles (UAVs) flying through a sequence of a random N number of waypoints (WPs) in three dimensions. Pontryagin's minimum principle was used to show that the straight-line path segments connecting the sequence of waypoints are time optimal [1]. An algorithm was designed so that the total trajectory path length of a UAV is approximately equal to the straight-line path of the waypoints. The trajectory path obtained was also compared with the one-circle method, and it was found that the proposed method has less path length. Issues related to this algorithm are explained in detail. Simulation results show the efficiency of the method.
Download or read book Small Unmanned Aircraft written by Randal W. Beard and published by Princeton University Press. This book was released on 2012-02-26 with total page 317 pages. Available in PDF, EPUB and Kindle. Book excerpt: Autonomous unmanned air vehicles (UAVs) are critical to current and future military, civil, and commercial operations. Despite their importance, no previous textbook has accessibly introduced UAVs to students in the engineering, computer, and science disciplines--until now. Small Unmanned Aircraft provides a concise but comprehensive description of the key concepts and technologies underlying the dynamics, control, and guidance of fixed-wing unmanned aircraft, and enables all students with an introductory-level background in controls or robotics to enter this exciting and important area. The authors explore the essential underlying physics and sensors of UAV problems, including low-level autopilot for stability and higher-level autopilot functions of path planning. The textbook leads the student from rigid-body dynamics through aerodynamics, stability augmentation, and state estimation using onboard sensors, to maneuvering through obstacles. To facilitate understanding, the authors have replaced traditional homework assignments with a simulation project using the MATLAB/Simulink environment. Students begin by modeling rigid-body dynamics, then add aerodynamics and sensor models. They develop low-level autopilot code, extended Kalman filters for state estimation, path-following routines, and high-level path-planning algorithms. The final chapter of the book focuses on UAV guidance using machine vision. Designed for advanced undergraduate or graduate students in engineering or the sciences, this book offers a bridge to the aerodynamics and control of UAV flight.
