Energy-efficient joint UAV secure communication and 3D trajectory optimization assisted by reconfigurable intelligent surfaces in the presence of eavesdroppers

We consider a scenario where an unmanned aerial vehicle(UAV),a typical unmanned aerial system(UAS),transmits confidential data to a moving ground target in the presence of multiple eavesdroppers.Multiple friendly reconfigurable intelligent surfaces(RISs) help to secure the UAV-target communication and improve the energy efficiency of the UAV.We formulate an optimization problem to minimize the energy consumption of the UAV,subject to the mobility constraint of the UAV and that the achievable secrecy rate at the target is over a given threshold.We present an online planning method following the framework of model predictive control(MPC) to jointly optimize the motion of the UAV and the configurations of the RISs.The effectiveness of the proposed method is validated via computer simulations.

A Comprehensive UAV Indoor Navigation System Based on Vision Optical Flow and Laser FastSLAM

这份报纸论述为室内的 quadrotor 的全面控制，航行，本地化和印射的答案无人的天线车辆(UAV ) 系统。三个主要传感器在 quadrotor 站台上被使用，也就是，一个惯性的测量单位，一个向下看起来的照相机和扫描激光变化查找者。与这安装， UAV 能要用体力地估计它的自己的速度和位置，当没有碰撞，沿着一个房间的内部墙飞时。在一个以后完成飞行，与收集了数据历史性的 UAV 路径和室内的环境能很好被估计。系统的自治航行部分不要求任何遥远的感觉信息或离线的计算力量，当印射被做时离线。完全的飞行测试被执行了验证忠实和性能航行答案。

Mobile Jammer-Aided Secure UAV Communications via Trajectory Design and Power Control

To further promote the achievable average secrecy rate for UAV-ground communications, a UAV-aided mobile jamming strategy was proposed in this paper. Specifically, an additional cooperative UAV is employed as a mobile jammer to transmit the jamming signal to help keep the source UAV closer to the ground destination, thus establishing more favorable legitimate link and enhancing the secrecy performance. We aimed to maximize the achievable secrecy rate by jointly optimizing the trajectories and transmit power of both source UAV and jammer UAV. To solve the considered non-convex optimization problem, we presented a block coordinate descent based iterative algorithm to address a sequence of approximated convex problems for the optimized parameter block by block to find a local optimal solution. Numerical results verify that the proposed algorithm can achieve significant secrecy rate gain compared to all the benchmark schemes.

Distributed tracking control of unmanned aerial vehicles under wind disturbance and model uncertainty

A distributed robust method is developed for cooperative tracking control of unmanned aerial vehicles under unknown wind disturbance and model uncertainty. The communication network among vehicles is a directed graph with switching topology. Each vehicle can only share its states with its neighbors. Dynamics of the vehicles are nonlinear and affected by the wind disturbance and model uncertainty. Feedback linearization is adopted to transform the dynamics of vehicles into linear systems. To account for the wind disturbance and model uncertainty, a robust controller is designed for each vehicle such that all vehicles ultimately synchronize to the virtual leader in the three-dimensional path. It is theoretically shown that the position states of the vehicles will converge to that of the virtual leader if the communication network has a directed spanning tree rooted at the virtual leader. Furthermore, the robust controller is extended to address the formation control problem. Simulation examples are also given to illustrate the effectiveness of the proposed method. © 2016 Beijing Institute of Aerospace Information.

Analysis of Design Directions for Ground Control Station (GCS)

This study is a preparation phase for integrated visualization of battlefield situation. To develop the ground control station for unmanned systems, many factors have to be considered from the design stages, such as layout, information component, representation scheme, and human operation methods. Considering such many factors can be very difficult, hence we conducted an in-depth investigation of design factors from major UAV stations around the world. We analyzed the design characteristics and the specifics. In conclusion, we were able to derive some common aspects of design characteristics, which lead to the successful design approach.

Research on an Urban Traffic Control System Based on DGPS

The basic principles of GPS (Global Positioning System) and DGPS (Differential GPS) are described. The principle and structure of vehicle navigation systems, and its application to the urban traffic flow guidance are analyzed. Then, an area coordinated adaptive control system based on DGPS and a traffic flow guidance information system based on DGPS are put forward, and their working principles and functions are researched. This is to provides a new way for the development of urban road traffic control systems.

无人机地面控制站通用化研究

无人机地面控制站作为无人机系统的信息汇聚中心和指挥控制中心,是保障飞行安全、遂行作战任务和共享侦察载荷信息的关键,同时也是无人机与其他作战力量实现互联互通的重要手段。目前不同的飞机平台单位、甚至相同单位不同的团队设计的地面控制站也无法通用,文中通过分析目前地面控制站现状,构建通用地面控制站型谱,建立通用化标准体系,设计系统和软件体系架构,提出无人机通用地面控制站关键技术解决方案。

跨介质无人机的技术问题与解决方案分析

阐述跨介质无人机作为一种能够在不同介质(水体、空气)中自由切换的多功能飞行器,受到广泛关注。分析跨介质无人机所面临的机械结构、能源与动力系统、导航与控制系统方面的技术问题,提出相应解决方案。通过优化机械结构、改进能源系统和升级导航控制系统的措施,有效地解决跨介质无人机的技术挑战,推动其在各个应用领域的发展。

Optimal combination of the correction model and parameters for the precision geometric correction of UAV hyperspectral images

Nowadays,with the rapid development of quantitative remote sensing represented by high-resolution UAV hyperspectral remote sensing observation technology,people have put forward higher requirements for the rapid preprocessing and geometric correction accuracy of hyperspectral images.The optimal geometric correction model and parameter combination of UAV hyperspectral images need to be determined to reduce unnecessary waste of time in the preprocessing and provide high-precision data support for the application of UAV hyperspectral images.In this study,the geometric correction accuracy under various geometric correction models(including affine transformation model,local triangulation model,polynomial model,direct linear transformation model,and rational function model)and resampling methods(including nearest neighbor resampling method,bilinear interpolation resampling method,and cubic convolution resampling method)were analyzed.Furthermore,the distribution,number,and accuracy of control points were analyzed based on the control variable method,and precise ground control points(GCPs)were analyzed.The results showed that the average geometric positioning error of UAV hyperspectral images(at 80 m altitude AGL)without geometric correction was as high as 3.4041 m(about 65 pixels).The optimal geometric correction model and parameter combination of the UAV hyperspectral image(at 80 m altitude AGL)used a local triangulation model,adopted a bilinear interpolation resampling method,and selected 12 edgemiddle distributed GCPs.The correction accuracy could reach 0.0493 m(less than one pixel).This study provides a reference for the geometric correction of UAV hyperspectral images.

UAV地面监测系统

地面监测系统在UAV自主导航与多设备协同通信中充当着重要的角色,监测站可完成对UAV的飞行姿态、参数调整、信息获取以及航线的手动规划。本文提出一套适用于UAV自动导航系统的地面监测站,该系统包括UAV基础参数监测、编队状态监测、图像数据接入等功能,依托数字信号传输设备与数字图像传输设备完成地面战与UAV的实时通信。测试结果表明,本文所设计的地面监测平台可满足UAV在自主导航时的信息监测需求。

基于Android系统的手持式无人机地面控制端的设计

在Android系统下,利用Eclipse开发平台和蓝牙技术,研究并设计实现一个满足小型无人机飞行需要的地面控制平台,该平台要求在手机终端能搜索连接模拟飞机模块,能对飞行器进行简单的飞行控制以及对飞行参数数据的显示,手机终端飞行参数能通过手动更新或自动更新以保持与飞行器参数一致。从而实现无人机地面站的便携化,为下一步更精准便携式地面站提供相关依据。

基于UWB的无人机自主导航系统设计

针对卫星拒止环境下的无人机导航,提出一种基于超宽带(Ultra Wide-Band,UWB)技术的局部定位系统,实现无人机定位与导航。首先利用UWB技术实现测距,进而解算无人机在局部坐标系下的三维坐标,然后基于扩展卡尔曼滤波(EKF)融合多传感器数据以提高无人机的定位精度。基于开源飞控Pixhawk搭建了无人机飞行验证平台,将UWB定位系统数据与飞控传感器数据融合,对无人机在局部坐标系下的自主飞行进行了仿真。最后通过实验验证了基于UWB的多传感器数据融合导航在无人机自主导航控制上的可行性,实现了无人机在地面平台上的自主起降、对地目标伴飞等飞行导航任务。

面向中继通信的空地协同无人机编队控制算法设计与仿真

随着无人机(UAV)应用场景的不断丰富,近年来利用无人机编队实现空地协同的任务日益增多。根据现阶段的编队体系和控制方法,该文设计一种基于行为策略的空地协同无人机编队控制算法:通过引入空地协同思想,为地面移动用户提供中继通信服务,扩大了无人机编队的通信覆盖范围。为7架无人机组成的编队设计了4种无人机队形,推导相应的单位中心站位标准,并使用Unity软件对空地协同无人机编队控制算法进行仿真,测试使用该算法的无人机编队在理想环境下的转弯性能和模拟实际环境下的避障、中继通信以及队形变化能力。基于所提出的空地协同算法,设计了两种任务方案:区域搜索覆盖主任务方案和用户失联搜救应急方案。实验仿真证明了改进的空地协同无人机编队控制算法及两种方案具有可行性。

基于控制点蒙特卡罗检验的无人机地形建模精度影响因素研究

针对消费级无人机相机单一、镜头畸变大,地形建模精度受航线设计和控制测量的影响等问题,设计了不同的数据采集方案和控制点蒙特卡罗检验,分析了相机倾角、航高和控制点数量对地形建模精度的影响。在黄土高原3个典型小流域的实验结果表明:①在进行无人机摄影测量数据处理时,应先使用蒙特卡罗检验对控制点质量进行分析,排除控制点误差再进行数据处理。②相机倾角方面,在无地面控制点时,采用较大角度的倾斜摄影不仅有利于提高样区整体精度,还优化了误差的空间分布;这与相机畸变模型的优化有关。在有地面控制点时,相机倾角对高程精度的影响不大,但是影响控制点饱和数量;相对于垂直摄影,倾斜摄影需要略多的控制点才能达到最优精度。③航高方面,在有地面控制点时,使用倾斜摄影有利于降低高程精度对航高变化的敏感性。在有地面控制点时,航高在60~160 m范围内对高程精度的影响不明显,且航高变化不影响控制点饱和数量。

无人机航测空三点误差分布及像控点对其精度影响机理

无人机以其机动灵活、受天气影响小、快速获取目标区域影像的优势已成为矿区地表形变监测的重要方法,如何提升无人机测量精度是亟需解决的关键问题。在系统分析无人机监测地表点精度影响因素基础上,重点研究了像控点质量对空三点误差分布、精度的影响规律。首先采用大量的重复观测实验的方法,研究揭示了在四周均匀布设像控点条件下,监测点平面位置、高程的误差特性及其分布特征;在此基础上,通过对像控点平面坐标、高程坐标施加随机误差,研究了像控点平面、高程精度与监测点平面、高程精度的对应关系。最后,依据前述研究成果,给出了提升无人机地表沉陷监测精度的策略。研究结果表明,在四周均匀布设像控点条件下,无人机测量点位平面、高程误差符合正态分布规律,但存在一定的系统误差影响;像控点平面坐标、高程坐标对空三解算平面坐标、高程坐标影响具有独立性;通过对多次测量结果进行数字平均可以有效提升测量精度。研究成果为采煤塌陷区无人机高精度监测方案设计提供理论与技术支撑。

地下复杂空间无人机研究进展及其面临的挑战

分析了地下复杂空间无人机的技术发展与应用现状,指出地下复杂空间无人机面临单体性能不足、环境态势感知与自主导航能力有限、编队协同能力有限等问题,针对上述问题,展望了地下无人机关键技术发展趋势:①小型化轻量化一体化无人机设计技术。通过改进无人机的机械结构,提高激光雷达、深度相机等信息感知传感器与控制系统的集成度,优化电源管理系统等,最终实现单体无人机巡航速度、续航时间等性能的提升;②GPS拒止环境下态势感知与自主导航技术。攻克即时定位与地图构建(SLAM)导航与实时路径规划等关键技术难题,围绕特定场景逐步突破算法的局限性,提升无人系统的感知能力、环境适应性和鲁棒性;③有限信息下编队协同控制技术。攻克异构/同构无人机集群协同、复杂信道环境下的无线通信等技术难题,通过优化无人机群体智能控制策略、信息交互机制及任务决策协同机制等,增强集群无人系统的鲁棒性,提高无人系统在地下复杂环境中的自适应能力,进而提升无人系统的任务执行效率与成功率。

一种新型单涵道式无人机控制系统设计

无人机(unmanned aerial vehicle,UAV)的应用场景的多样化及复杂化对飞行器的功能、性能、安全性提出了新的挑战。提出一种兼具垂直起降、空中悬停和高速飞行能力且安全性更高的新型单涵道式飞行器整体设计,分析并推导飞行器的动力学方程以降低系统的耦合性。为了提高系统的实时性与鲁棒性,在飞行器软件系统中移植UCOSⅢ,并基于双闭环比例微分积分(proportion integral derivative,PID)算法设计其姿态控制器。通过Unity3D和C#编写兼具模拟飞行的地面站程序实现多平台控制,最终完成飞行器样机的总体设计且通过试飞实验验证其飞行性能。研究成果对单涵道飞行器的实际工程应用具有重要的借鉴意义。

面向定向培养军士生的课程思政建设探索与实践——以《无人机控制与导航技术》为例

针对目前定向培养军士生的课程思政建设中存在的重视不足、效果不佳、影响不力等问题,以《无人机控制与导航技术》课程为例,通过课程思政建设改进课程教学。从教学设计创新化、教学内容定制化和教学手段多样化等三方面着手,由传统教学模式转变为“课程设计、知识技能、课程思政”三大主线并进的课程教学模式,达到能力培养与价值引领同频共振的效果。

无人机地面控制站软件通用化研究

无人机地面控制站作为无人机系统的核心,主要功能包括任务规划、飞行监视与控制、任务载荷监视与控制、链路监视与控制、综合数据管理和情报分发等。经过多年建设,我国无人机地面控制站运用体系已初步形成,但仍然存在各型号无人机地面控制站不通用的问题。软件系统是地面控制站的核心,同样面临如何实现通用化的问题,通过分析地面控制站的软件通用化技术途径,利用“通用模块+专用模块”的设计思路,建立基于数据分发服务(DDS)的地面控制站软件架构,给出一种通用的软件模块划分方法。按照该种设计方法基本可以实现地面控制站软件通用化,再结合地面控制站硬件通用化设计,能够推动地面控制站通用化发展。

MEMS-Based Low-Cost Flight Control System for Small UAVs

Small unmanned air vehicles （UAVs） can be used for various kinds of surveillance and data collection missions. The UAV flight control system is the key to a successful mission. This paper describes a low-cost micro-electro mechanical system-based flight control system for small UAVs. The integrated hardware flight control system weighs only 24 g. The system includes a highly-integrated wireless transmission link, which is lighter than traditional links. The flight control provides altitude hold control and global positioning system navigation based on gain scheduling proportional-integral-derivative control. Flight tests to survey the grass quality of a large lawn show that the small UAV can fly autonomously according to a series of pre-arranged waypoints with a controlled altitude while the wireless video system transmits images of the surveillance target to a ground control station.