机载光电探测系统红外性能测试靶板的研究

为了对机载光电探测系统外场性能进行定量评价,设计了野外红外性能测试靶板,论述了该靶板的设计、原理、结构、标定和应用,利用该靶板可以开展不同气象条件下系统的作用距离、探测灵敏度、空间分辨率、温度分辨率、点目标探测等性能测试研究。     

基于5G和无人机智能组网的应急通信技术

针对现有应急通信系统面临的低速率、高时延、带宽不足和互联互通性差等问题,提出了一种基于5G和无人机智能组网的应急通信系统技术路线,并对其中部分关键技术进行了剖析,以期为提升救援力量在受灾地域的应急通信保障能力提供重要支撑。通过理论分析可知,该技术路线能够实现目标区域内无人机编队的智能组网和部署、5G信号的覆盖和5G通信的联通,拓展5G网络的覆盖范围,可在通信基础设施损毁的环境下实现用户终端之间以及用户终端与应急指挥中心之间的互联互通,具有一定的应用前景。     

面向无人机航拍场景的轻量化目标检测

针对无人机航拍场景下的实时目标检测任务,以YOLOv5为基础进行改进,给出了一种轻量化的目标检测网络YOLOv5-tiny.通过将原CSPDarknet53骨干网络替换为MobileNetv3,减小了网络模型的参数量,有效提高了检测速度,并进一步通过引入CBAM注意力模块和SiLU激活函数,改善了因网络简化后导致的检测精度下降问题.结合航拍任务数据集VisDrone的特性,优化了先验框尺寸,使用了Mosaic,高斯模糊等数据增强方法,进一步提高了检测效果.与YOLOv5-large网络相比,以降低17.4%的mAP为代价,换取148%的检测效率(FPS)提升,且与YOLOv5s相比,在检测效果略优的情况下,网络规模仅为其60%.     

Utility of remotely operated underwater vehicle in flood inundation mapping for dam failure: A case study of Lake Tuscaloosa Dam

A remotely operated underwater vehicle (ROV) is a tethered underwater mobile device that can conduct a bathymetric survey cost-efficiently. Assessment of the utility of ROV-based bathymetric surveys in flood inundation mapping remains limited. This study aims to examine the utility of ROV-based bathymetric surveys in high-resolution flood inundation mapping for a hypothetical case study of the Lake Tuscaloosa Dam breach in the state of Alabama, USA. This study conducted the sensitivity test of flood inundation mapping to the river channel depth (ROV-based vs. digital elevation model [DEM]-based) and initial flow condition (e.g., wet vs. dry), via six different simulations of the parallelized diffusion hydrodynamic model (pDHM). This study found that the ROV-based pDHM runs had higher maximum water depths over the flood-inundated areas, ranging from +73% to +166% of the simulated depths of the DEM-based pDHM runs. However, the impact of initial streamflow condition on the maximum depths was limited. This study also found that the pDHM runs with a dry initial flow condition delayed the time to reach the maximum depth after the dam breach by 2 h relative to the pDHM runs with a wet initial streamflow condition. This study suggests that ROV-based bathymetry surveys improve flood inundation mapping by emphasizing the influence of river channel depth, initial streamflow conditions, and bathymetry, thereby bolstering community resilience to a potential human-made hazard such as dam failure.     

面向无人机风机巡检的光照条件分析方法

在无人机风机巡检作业中, 光照异常会严重影响拍摄到的图像质量, 导致风机叶片在图像中亮度异常, 叶片上的裂纹等细微缺陷无法被有效判定, 影响风机的安全稳定运行. 本文针对此问题, 开展风机巡检中的光照条件分析技术研究, 在巡检前, 根据规划的航迹及太阳的方位进行光照情况预判; 在巡检中, 根据风机叶片及塔筒的分割结果,...     

基于仿斑马鱼和仿鹰眼视觉的复杂背景下目标识别

针对反制无人机识别系统在公共场所内部复杂背景下的无人机识别问题,该文研究了一种基于仿斑马鱼模板匹配视觉识别和仿鹰眼视觉注意的目标识别方法,通过建立不同姿态的无人机模板数据库,采用仿鹰眼视觉搜索机制,结合尺度不变特征变换,将姿态模板图像与目标进行匹配,获得粗略的目标区域。然后计算模板姿态与目标姿态的Hausdorff距离,比较目标姿态相似性,获得最相似姿态。采用仿鹰眼视觉注意机制对遮挡图像进行处理,提高目标识别的显著性。实验结果表明,该方法能够在不同复杂背景下实现无人机的准确识别,与光谱残差的显著性目标识别方法相比,平均运行时间提高23.5%,与差异哈希算法相比,具有更高的结构相似性指数。     

基于粒子群优化的串级模糊PID无人机飞行控制系统

为了解决无人机飞行控制系统存在的平稳控制响应慢、自适应能力差,抗干扰能力弱的问题,本文分析了无人机飞行控制系统的原理,建立了无人机飞行控制模型,在串级模糊PID控制的条件下,利用粒子群优化算法的迭代寻优能力,实时确定模糊控制中的量化因子、比例因子以及初始PID参数,通过模糊控制在线调整PID参数,使平稳控制中的参数时刻保持最优化,设计了一种基于粒子群优化的串级模糊PID的飞行控制系统。实验结果表明：当量化因子e、ec的值分别为3、0.75,比例因子k1、k2、k3的值分别为0.5、2、0.5时,系统稳定性达到最优。相比于串级PID控制与串级模糊PID控制,通过粒子群优化后的控制系统具有更优的控制精度和稳定性,能较好地提高系统的性能指标,满足快速高效调平的飞行要求。     

Radar detection of drones responding to honeybee queen pheromone

The response of honey bee (Apis mellifera L.) drones to queen pheromone(s) (either natural from a mated queen, or synthetic from a lure) was recorded using an X-band, ground-based radar. The distribution of drones (insect targets on the radar screen) changed from a scattered distribution to a line concentration (downwind) when the pheromone was released. Displacement within the line concentration was toward the pheromone. This response was seen as far as 800±15 m downwind from a lure with 10 mg of synthetic 9-oxodec-trans-2-enoic acid (9-ODA) and as far as 420±15 m from a mated queen. These studies demonstrate that queen pheromone can be detected by drones at much greater distances than previously believed and illustrate how X-band radar may be used to establish the distances at which insects of similar or larger size respond to pheromones.Mention of a commercial or proprietary product does not constitute an endorsement by the USDA.     

某型高速 无人 靶机飞行控制的设计与 实现

按照某型高速无人靶机飞行特性和性能要求,详细给出了基于DSP为处理核心的飞行控制系统硬件组成和逻辑功能结构,介绍了无人靶机飞行控制策略,设计并开发了配套的地面测控程序,并进行靶机的半物理仿真实验。仿真结果表明该飞行控制系统性能良好,符合高速无人靶机的飞行要求,并成功应用于某型无人机飞行试验。     

植保无人机在农作物病虫害防治中的应用分析

文章介绍了植保无人机的基本概念及其优、劣势,分析其发展现状及应用前景,最后就植保无人机的应用推广提出几点建议。