共查询到20条相似文献,搜索用时 15 毫秒
1.
Gon?alo Charters Santos Cruz Pedro Miguel Martins Encarna??o 《Journal of Intelligent and Robotic Systems》2012,65(1-4):203-217
This work is framed within the PITVANT project and aims to contribute to the development of obstacle avoidance techniques for unmanned aerial vehicles (UAVs). The paper describes the design, implementation and experimental evaluation of a potential field obstacle avoidance algorithm based on the fluid mechanics panel methods. Obstacles and the UAV goal position are modeled by harmonic functions thus avoiding the presence of local minima. Adaptations are made to apply the method to the automatic control of a fixed wing aircraft, relying only on a local map of the environment that is updated with information from sensors onboard the aircraft. Hardware-In-Loop simulations show the good performance of the proposed algorithm in the envisioned mission scenarios for the PITVANT vehicles. 相似文献
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The formation control problem of a team of Vertical Take-Off and Landing (VTOL) Unmanned Aerial Vehicles (UAVs) with communication delays is addressed. Based on the extraction algorithm presented in Abdessameud and Tayebi (2010a), we propose a new design methodology that simplifies the design of formation control laws with delayed communication for this class of under-actuated systems. Three control schemes are presented that provide delay-dependent and delay-independent results with constant and time-varying communication delays. The stability of the overall closed loop system in each scheme is established using Lyapunov–Krasovskii functionals. The proposed design methodology achieves global results in terms of the position and removes the requirement of the linear-velocity measurements. Simulation results are provided to show the effectiveness of the proposed control schemes. 相似文献
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Nour El Houda Bahloul Saadi Boudjit Marwen Abdennebi Djallel Eddine Boubiche 《计算机科学技术学报》2018,33(2):263-276
研究人员的某社区显示出到自治雄蜂或 UAV (无人的天线车辆) 的兴趣与无线通讯网络的来临增加了。这些网络允许 UAV 以一种特定的方式更高效地合作以便在特定的环境完成特定的任务。到那么,当保持经由收音机连接在它的组与另外的节点连接了时,每只雄蜂独立地遨游。这个连接能故意被维持一会儿抑制雄蜂的活动性。这将对涉及在来源和一个目的地之间的给定的传播的一条给定的路径的雄蜂合适。这限制能在传播过程的结束被移开,每只担心的雄蜂的活动性从其它变得再独立。在这个工作,我们建议为 UAV 的一个基于成群的路由协议叫了 BR-AODV。协议为当数据正在被播送时,维持的连接和线路为雷纳兹机制的按需的线路计算,和 Boids 利用一个众所周知的特定的路由协议。而且,自动扎根的基础车站发现机制为为即时应用程序的上下文需要的一个积极雄蜂和地面网络协会被介绍了。BR-AODV 的表演被评估,与古典 AODV 路由的相比,协议和结果证明 BR-AODV 以延期,产量和包损失超过 AODV。 相似文献
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四旋翼无人机自适应导航控制 总被引:2,自引:0,他引:2
研究四旋翼(Quadrotor)无人机导航控制问题。针对传统的四旋翼无人机导航控制方法的目标定位误差和实时性差问题,提出了基于CLOS技术的导航控制方法。采用CLOS技术所开发的导航控制系统使得四旋翼无人机能够在移动停机坪完成自主导航和着陆的任务,并详细研究了导航控制系统的设计和仿真。仿真结果显示了所设计的导航控制系统的性能和有效性,可应用于四旋翼无人机的实时导航。 相似文献
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Christopher Korpela Matko Orsag Paul Oh 《Journal of Intelligent and Robotic Systems》2014,73(1-4):725-736
A hardware-in-the-loop test rig is presented to bridge the gap between basic aerial manipulation research and the ability of flying robots to perform tasks such as bridge repair, agriculture care, container inspection and other applications requiring interaction with the environment. Unmanned aerial vehicles have speed and mobility advantages over ground vehicles and can operate in 3-dimensional workspaces. In particular, the usefulness of these capabilities is highlighted in areas where ground robots cannot reach or terrains they are unable to navigate. However, most UAVs operating in near-earth or indoor environments still do not have the payload capabilities to support multi-degree of freedom manipulators. We present a rotorcraft emulation environment using a 7 degree of freedom manipulator. Since UAVs require significant setup time and to avoid potential crashes, our test and evaluation environment provides repeatable experiments and captures reactionary forces experienced during ground interaction. Recent experiments in insertion tests are presented. The lessons learned from these experiments will be ported onto an actual air vehicle with manipulator. 相似文献
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An iterative temporal registration algorithm is presented in this article for registering 3D range images obtained from unmanned
ground and aerial vehicles traversing unstructured environments. We are primarily motivated by the development of 3D registration
algorithms to overcome both the unavailability and unreliability of Global Positioning System (GPS) within required accuracy
bounds for Unmanned Ground Vehicle (UGV) navigation. After suitable modifications to the well-known Iterative Closest Point
(ICP) algorithm, the modified algorithm is shown to be robust to outliers and false matches during the registration of successive
range images obtained from a scanning LAser Detection And Ranging (LADAR) rangefinder on the UGV. Towards registering LADAR
images from the UGV with those from an Unmanned Aerial Vehicle (UAV) that flies over the terrain being traversed, we then
propose a hybrid registration approach. In this approach to air to ground registration to estimate and update the position
of the UGV, we register range data from two LADARs by combining a feature-based method with the aforementioned modified ICP
algorithm. Registration of range data guarantees an estimate of the vehicle's position even when only one of the vehicles
has GPS information. Temporal range registration enables position information to be continually maintained even when both
vehicles can no longer maintain GPS contact. We present results of the registration algorithm in rugged terrain and urban
environments using real field data acquired from two different LADARs on the UGV.
★Commercial equipment and materials are identified in this article in order to adequately specify certain procedures. Such
identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does
it imply that the materials or equipment identified are necessarily the best available for the purpose. 相似文献
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Bruno Hérissé Tarek Hamel Robert Mahony François-Xavier Russotto 《Autonomous Robots》2010,29(3-4):381-399
This paper presents a nonlinear controller for terrain following of a vertical take-off and landing vehicle (VTOL). The VTOL vehicle is assumed to be a rigid body, equipped with a minimum sensor suite (camera, IMU and barometric altimeter) maneuvering over a textured rough terrain made of a concatenation of planar surfaces. Assuming that the forward velocity is separately regulated to a desired value, the proposed control approach ensures terrain following and guarantees that the vehicle does not collide with the ground during the task. The proposed control acquires an optical flow from multiple spatially separate observation points, typically obtained via multiple cameras or non collinear directions in a unique camera. The proposed control algorithm has been tested extensively in simulation and then implemented on a quadrotor UAV to demonstrate the performance of the closed-loop system. 相似文献
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基于PH曲线的无人机路径规划算法 总被引:2,自引:0,他引:2
研究了无人机可飞行路径规划问题,传统路径规划算法不能生成满足无人机运动学约束的可飞行路径.为解决上述问题,提出了将曲率连续的Pythagorean Hodograph (PH)曲线(又称勾股速端曲线)直接用于无人机路径规划的方法,利用PH曲线曲率连续、曲线平滑以及有理特性,在已知威胁的环境中可直接得到满足最大曲率约束且曲率连续的无人机可飞行路径.采用遗传模拟退火算法搜索避开环境中威胁体,并满足约束条件的最优PH路径,使仿真过程结合遗传算法和模拟退火算法的优点,取长补短,提高搜索效率,加强全局搜索能力.仿真结果表明,遗传模拟退火算法能在较少的进化代数下得到最优路径解,且所得的满足约束条件的PH路径曲率连续,为无人机飞行控制提供了依据. 相似文献
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针对无人机的三维航迹规划问题,提出了一种基于几何法的航迹规划算法.通过对无人机飞行航迹的分析,将无人机航迹看作是由一系列直线、圆弧和螺旋线的有序组成.研究了无人机最大过载系数、最大平飞速度、升限等性能与航迹可行性的关系,得出生成最优航迹的限定条件.讨论了几何法无人机航迹规划的步骤.按照几何原理对无人机航迹进行了规划,将无人战斗机的机动性能在航迹中充分体现出来.计算机仿真结果表明用几何法规划的航迹具有较好的适用性. 相似文献
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Roberto Conde David Alejo Jose Antonio Cobano Antidio Viguria Aníbal Ollero 《Journal of Intelligent and Robotic Systems》2012,65(1-4):495-505
This paper presents a Conflict Detection and Resolution (CDR) method for cooperating Unmanned Aerial Vehicles (UAVs) sharing airspace. The proposed method detects conflicts using an algorithm based on axis-aligned minimum bounding box and solves the detected conflicts cooperatively using a genetic algorithm that modifies the trajectories of the UAVs with an overall minimum cost. The method changes the initial flight plan of each UAV by adding intermediate waypoints that define the solution flight plan while maintaining their velocities. The method has been validated with many simulations and experimental results with multiple aerial vehicles platforms based on quadrotors in a common airspace. The experiments have been carried out in the multi-UAV aerial testbed of the Center for Advanced Aerospace Technologies (CATEC). 相似文献
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Energy Management in Swarm of Unmanned Aerial Vehicles 总被引:1,自引:0,他引:1
Jeremie Leonard Al Savvaris Antonios Tsourdos 《Journal of Intelligent and Robotic Systems》2014,74(1-2):233-250
Automated maintenance has become a necessity for Unmanned Aerial Vehicle (UAV) systems to function in remote environments for an extended period of time with a higher number of vehicles. Once removed from the energy management loop, the human operator is free to concentrate on higher level task management and data analysis. This paper firstly describes the design, test and construction of an autonomous Ground Recharge Stations (GRS) for battery-powered quadrotor helicopter. In order to incorporate the charging of the quadrotors in the overall swarm behaviour, the focus of the research presented here has been to reduce the charging phase of a single vehicle by developing safer electrical contacts and using a balancer in the charging process. The amount of extra current available from the new design easily pushed the flying-time/charging-time ratio of the quadrotors over 1. The paper then describes a novel approach for the integration of this technology into an energy efficient multi-agent system. The development of a prioritisation function and queuing protocols between the UAVs and GRSs demonstrate an optimised solution to the assignment problem dependent on the mission profile. Numerical experiments show that the system’s energy management remains efficient regardless of number and position of the platforms, or nature of the environment. 相似文献
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Dasgupta P. 《IEEE transactions on systems, man, and cybernetics. Part A, Systems and humans : a publication of the IEEE Systems, Man, and Cybernetics Society》2008,38(3):549-563
Over the past few years, automatic target recognition (ATR) has emerged as an essential image analysis tool to identify objects from temporally and spatially disjoint possibly noisy image data. For many current applications, ATR is performed by unmanned aerial vehicles (UAVs) that fly within a reconnaissance area to collect image data through sensors and upload the data to a central ground control station for analyzing and identifying potential targets. The centralized approach to ATR introduces several problems, including scalability with the number of UAVs, network delays in communicating with the central location, and the susceptibility of the system to malicious attacks on the central location. These challenges can be addressed by using a distributed system for performing ATR. In this paper, we describe a multiagent-based prototype system that uses swarming techniques inspired from insect colonies to perform ATR using UAVs in a distributed manner within simulated scenarios. We assume that UAVs are constrained in the resources available onboard and in their capabilities for performing ATR due to payload limitations. Our focus in this paper is on the coordination aspects between UAVs to efficiently decide how they are to act by using a swarming mechanism. We describe algorithms for the different operations performed by the UAVs in the system and for different swarming strategies, which are embedded within software agents located on the UAVs. We provide empirical simulations of our system within a simulated area of interest to determine its behavior in different scenarios with varying operational constraints. Our experimental results indicate that swarming strategies for distributed ATR perform favorably compared with centralized ATR strategies. 相似文献
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针对四旋翼无人机无人车联合运动缺乏对系统成员姿态约束的问题,研究了一种基于模型预测控制(MPC)的分布式联合运动控制方法.基于虚拟结构法,使用虚拟领航者策略,以虚拟领航者提供参考轨迹及参考速度,分别在各无人器平台上转换成各自所需的预测时域信息,结合推导的各无人器的状态空间模型滚动优化实现预测控制.限定四旋翼高度方向运动状态与偏航角,构造以俯仰角、横滚角与重力加速度乘积为位置运动输入的状态空间模型,将无人机内环姿态控制约束加入位置运动,增强飞行稳定性.改良无人车状态空间模型,增加速度信息得到可提供位置速度追踪的增广状态空间模型,增强运动追踪能力.仿真表明在满足无人器姿态约束条件下,能够保证联合运动的位置速度精度. 相似文献
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A Visual Global Positioning System for Unmanned Aerial Vehicles Used in Photogrammetric Applications
Andrea Cesetti Emanuele Frontoni Adriano Mancini Andrea Ascani Primo Zingaretti Sauro Longhi 《Journal of Intelligent and Robotic Systems》2011,61(1-4):157-168
The combination of photogrammetric aerial and terrestrial recording methods can provide new opportunities for photogrammetric applications. A UAV (Unmanned Aerial Vehicle), in our case a helicopter system, can cover both the aerial and quasi-terrestrial image acquisition methods. A UAV can be equipped with an on-board high resolution camera and a priori knowledge of the operating area where to perform photogrammetric tasks. In this general scenario our paper proposes vision-based techniques for localizing a UAV. Only natural landmarks provided by a feature tracking algorithm will be considered, without the help of visual beacons or landmarks with known positions. The novel idea is to perform global localization, position tracking and localization failure recovery (kidnapping) based only on visual matching between current view and available georeferenced satellite images. The matching is based on SIFT features and the system estimates the position of the UAV and its altitude on the base of the reference image. The vision system replaces the GPS signal combining position information from visual odometry and georeferenced imagery. Georeferenced satellite or aerial images must be available on-board beforehand or downloaded during the flight. The growing availability of high resolution satellite images (e.g., provided by Google Earth or other local information sources) makes this topic very interesting and timely. Experiments with both synthetic (i.e., taken from satellites or datasets and pre elaborated) and real world images have been performed to test the accuracy and the robustness of our method. Results show sufficient performance if compared with common GPS systems and give a good performance also in the altitude estimation, even if in this last case there are only preliminary results. 相似文献
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Goncharenko V. I. Lebedev G. N. Mikhailin D. A. 《Journal of Computer and Systems Sciences International》2019,58(1):147-158
Journal of Computer and Systems Sciences International - This paper suggests a novel approach to online two-dimensional route planning for a coordinated flight of a group of unmanned aerial... 相似文献