消费级无人机在1∶500带状地形图测图中的应用

无人机倾斜摄影技术已成功应用于各项国民经济建设,如地籍测量、大面积区域测量等,但大多采用价格昂贵的固定翼和多镜头的旋翼无人机,针对带状地形图的应用研究较少。鉴于此,采用消费级大疆精灵4无人机和ContextCapture三维建模软件,通过外业数据采集和内业数据处理,生成三维模型、DOM、DSM、三维点云数据,利用清华山维（EPS）采集数据、CASS7.1进行编辑。获得数字线划图（DLG）,并将其与利用RTK测量的地形图进行对比分析,通过对3类主要地物的精度比对,得出道路精度为0.042m,满足1∶500带状地形图测图要求。     

无人机航迹规划与状态追踪系统

针对小型无人机控制的复杂性,设计了一套地面站综合控制系统。该系统具有航向的监测与控制、航迹的规划与显示、任务信息的接收与执行等功能,可以实现小型无人机的超视距控制和任务信息的回传与追踪。实验表明,系统可实现64bit数据帧间隔50ms收发与间隔1 000ms显示数据更新,满足实际应用需求。     

海南东寨港海底村庄遗址遥感观测与分析

利用高精度的无人机遥感正射影像、数字高程模型、Landsat8卫星遥感影像以及野外实地观测数据,以空间考古学方法为主要手段,研究海南东寨港海底村庄遗址的空间分布、现存状态及其演变规律。研究结果如下：1）海底村庄遗址均匀分布在东寨河古河道两侧。2）海底村庄遗址处于陆海相互作用的前沿地带,地质构造条件不稳定,遗址受潮汐、波浪、地面下沉和人类影响较为严重,部分已经沉陷到海面以下,部分只有在退潮后才会露出。3）林市村附近的海底村庄遗址受地震断裂影响将继续下沉。遗址中间部分已被潮水涨落冲刷殆尽,被冲刷面积约为1 871.5 m²,占遗址总面积的31.5%。     

Federated reinforcement learning approach for detecting uncertain deceptive target using autonomous dual UAV system

This paper develops a cooperative federated reinforcement learning (RL) strategy that enables two unmanned aerial vehicles (UAVs) to cooperate in learning and predicting the movements of an intelligent deceptive target in a given search area. The proposed strategy allows the UAVs to autonomously cooperate, through information exchange of the gained experience to maximize the target detection performance and accelerate the learning speed while maintaining privacy. Specifically, we consider a monitoring model that includes a search area, a charging station, two cooperative UAVs, an intelligent deceptive uncertain moving target, and a fake (false) target. Each UAV is equipped with a limited-capacity rechargeable battery and a communication unit for exchanging the gained experience. The problem of maximizing the detection probability of the uncertain deceptive target using cooperative UAVs is mathematically modeled as a search-benefit maximization problem, which is then reformulated as a Markov decision process (MDP) due to the uncertainty nature of the problem. Because there is no prior information on the targets’ movement, a cooperative RL, is utilized to tackle the problem. The proposed cooperative RL-based algorithm is a distributed collaborative mechanism that enables the two UAVs, i.e., agents, to individually interact with the operating environment and maximize their cumulative rewards by converging to a shared policy while achieving privacy. Simulation results indicate that a cooperative RL-based dual UAV system can noticeably improve the target detection probability, reduce the detection performance, and accelerate the learning speed.     

浅谈无人机系统在民航业的应用

目前国内的UAS运营单位可以分为公共航空运输运营人和通用航空运营人两类,而通用航空运营人将会较早地面临UAS发展的影响,一些原来有人驾驶航空器开展的作业,将逐渐由UAS替代。而作为公共航空运输运营人的我国民航业,也应加快对无人机系统的研究,了解UAS的特点及优势,现行情况及应用前景,面临的问题和未来的发展方向等,应对UAS对民航业乃至整个航空业所带来的挑战与机遇,从而促进民航业的发展。     

基于激光雷达的玉米全生育期株高变化监测

作物表型是育种和农业生产中重要的筛选和指示指标,然而近年来作物表型组学发展的相对滞后一定程度上阻碍了精细农业和分子育种的进展。作物表型特征参数亟需一种精确快速的测量手段来打破这一瓶颈。传统测量、数字图像、计算机视觉等目前较为普遍的作物表型测量方式可以获取部分表型参数但精度和时效上有待提高。激光雷达是一种新型主动遥感技术,具有高精度、空间分辨率获取三维数据等特点,逐步在作物的三维结构获取和表型参数提取中显现优势。本研究拟采用地基激光雷达完全全育期的玉米点云数据采集,分析株高在不同生育期的变化规律,为表型-基因型的交叉分析提供数据支持。     

面向实战的无人机飞行控制专业课程教学模式改革研究

鉴于目前无人机飞行控制专业课程教学模式与实战脱节、实战能力培养效果不佳的问题,首先对无人机飞行操控人员实战能力模型进行分析,然后对无人机飞行控制专业课程的教学内容、教学方法和教学手段进行改革研究,最后以无人机飞行控制专业学员为例对教学模式改革效果进行分析,以期探索出适应无人机实战能力培养的教学模式,为培养能打仗、打胜仗的高素质无人机装备人才服务。     

基于MPU9250的无人机姿态信息采集及处理

研究MPU9250多轴姿态传感器在无人机上的姿态信息采集,通过对九轴传感器内的陀螺仪,重力加速度计,磁力计的数据接收后,结合卡尔曼滤波算法对其数据进行精准的解算;搭建了一个无人机姿态模拟的物理实验平台,进行无人机运动状态下的信息采集;最后,在MATLAB的数据仿真下测试其性能。实验结果表明该方法可使无人机信息采集的精准度提升一倍。     

Design of rules for in-flight non-parametric tuning of PID controllers for unmanned aerial vehicles

Designing high performance controllers for multirotors is a rigorous task that is often solved by trial and error approach. Trial and error tuning usually results in non-optimal controller parameters. Tuning controllers based on the existing quadrotor models would result in poor performance of quadrotors due to simplifications and inaccuracies in the underlying models. In this paper optimal tuning rules for quadrotor attitude dynamics are designed, which guarantees near-optimal performance and robustness. A single in-flight run of the Modified Relay Feedback Test that takes only few seconds with guaranteed stability is enough to have near-optimal tuning of the controller. The designed tuning rule is tested experimentally in-flight on a custom-built quadrotor. The results showed significant advantages in performance and robustness due to the proposed approach.     

基于INS/BD-2组合的无人机导航算法研究

无人机在军事、民用领域发挥着越来越重要的作用,提高无人机导航系统的精度有十分重要的意义.为达到提高无人机导航精度的目的,将惯性导航系统（INS）与中国北斗二号（BD-2）相融合,提出了INS/BD-2组合的无人机导航策略.经过分析,建立了基于间接法的系统模型,其测量方程为非线性方程.在组合导航算法上采用了处理非线性问题常用的粒子滤波算法对组合导航系统进行解算,并通过MATLAB软件对算法进行了仿真分析,仿真结果证明,与传统的EKF算法相比,该算法可提高组合导航系统的导航精度.