载人潜水器混合动力中辅助电池容量的估算及验证系统

在燃料电池与蓄电池混合动力载人潜水器中,蓄电池的类型及容量是影响混合动力系统的响应特性、安全性、体积、重量的重要因素。文章首先针对启动、大功率突变及应急等工况进行分析,对蓄电池进行选型与容量配置,然后为验证估算容量值是否满足系统要求,开展了铅酸蓄电池放电电流与容量的建模,提出基于状态的燃料电池与铅酸蓄电池的功率分配方法及铅酸蓄电池SOC的估算方法,最后基于MATLAB GUI搭建铅酸电池容量验证系统,通过该容量验证系统,不仅可对混合动力系统中辅助蓄电池配置方案进行校核与优化设计,还可为系统是否设置重载询问提供依据。     

Monocular visual servo-based stabilization control of underactuated unmanned surface vehicle北大核心CSCD

［Objectives ］ Aiming at the accurate posture stabilization problem of an under-actuated unmanned surface vehicle (USV) in GPS-denied environments, a monocular visual servo stabilization control scheme is proposed based on homography.［Methods］By virtue of the homography decomposition technique, posture errors with an unknown scale factor are directly reconstructed from current and desired images, which thoroughly removes the calibration of extrinsic camera parameters and priori information on visual targets; with respect to the under-actuation constraint, a periodic function to persistently excite the yaw angle is incorporated into the continuous time-variant output feedback controller, allowing the USV to be stabilized in the absence of image depth, movement velocities and model parameters.［Results］Under the framework of the Lyapunov theory, the closed-loop visual servo system of the USV is rigorously proven to be asymptotically stable by Barbalat lemma.［Conclusions］By installing an onboard monocular camera, USV posture errors can be precisely stabilized with the aid of the proposed visual servo strategy, providing significant technique support for practical applications including docking, berthing, dynamic positioning, etc. © 2022 Journal of Clinical Hepatology. All rights reserved.     

军用 UUV 光电探测技术的应用方向*

国外军用水下无人航行器向“大型化、多用途”的方向发展,为满足情报、监视、侦察,反水雷战,反潜战和时敏打击的军事需求,国外UUV光电探测装备开展了大量的目标自动识别等智能化、远距离激光扫描成像等新技术的研究,最后给出了我国UUV光电探测装备的发展建议。     

Application of A* algorithm for real-time path re-planning of an unmanned surface vehicle avoiding underwater obstacles

This paper describes path re-planning techniques andunderwater obstacle avoidance for unmanned surface vehicle （USV）based on multi-beam forward looking sonar （FLS）. Near-optimalpaths in static and dynamic environments with underwaterobstacles are computed using a numerical solution procedure basedon an A algorithm. The USV is modeled with a circular shape in 2degrees of freedom （surge and yaw）. In this paper, two-dimensional（2-D） underwater obstacle avoidance and the robust real-time pathre-planning technique for actual USV using multi-beam FLS aredeveloped. Our real-time path re-planning algorithm has beentested to regenerate the optimal path for several updated frames inthe field of view of the sonar with a proper update frequency of theFLS. The performance of the proposed method was verifiedthrough simulations, and sea experiments. For simulations, theUSV model can avoid both a single stationary obstacle, multiplestationary obstacles and moving obstacles with the near-optimaltrajectory that are performed both in the vehicle and the worldreference frame. For sea experiments, the proposed method for anunderwater obstacle avoidance system is implemented with a USVtest platform. The actual USV is automatically controlled andsucceeded in its real-time avoidance against the stationary underseaobstacle in the field of view of the FLS together with the GlobalPositioning System （GPS） of the USV.     

大深度载人潜水器极限承载能力非线性有限元分析方法研究

大深度载人潜水器载人舱的极限承载能力是载人潜水器安全性的保障,在设计制造中非常关键。本文基于非线性有限元方法,对大深度载人潜水器球形载人舱极限承载能力进行了分析计算,提出了大深度载人潜水器球形载人舱极限承载能力非线性有限元计算中的影响因素;并与极限承载能力设计新公式计算结果进行对比,验证了本文非线性有限元分析方法和设计新公式的广泛适用性,为大深度载人潜水器建造规范和检验指南的制定奠定了基础。     

水面高速无人艇自主控制系统研究分析

水面高速无人艇具有小巧、隐蔽、智能等优点,因其部署机动性能佳、使用方便、优势众多,无论是军用还是民用,都能在极端环境中完成执行人员难以执行的任务。其自主控制系统是控制的核心,直接关系到任务完成得圆满与否,成为当今世界各国的研究热点。通过对自主控制内涵的定义,分析了研究现状和发展趋势,针对国际上对自主控制系统的研究热点,剖析其关键技术。结合我国的研究现状提出相应的应对策略建议。     

仿生弹药时代的新浪潮

现代战争更大可能的是发生局部战争,需要大量的特种弹药执行特种任务。近几年随着仿生弹药开始进入人们的视野,它具有其他常规弹药不具备的一些优良新能,将势必会引领弹药发展的新浪潮。论文以美军为例,阐述了仿生弹药的研究现状,介绍了仿生弹药的发展趋势以及研制过程中亟待解决的若干关键问题。     

基于RTK和无人艇的内河固定断面测量系统设计

为了提高固定断面测量的效率,改善目前固定断面测量存在的不足,设计了基于RT K和无人艇的内河固定断面测量系统。通过分析内河固定断面测量的特点和需求,构建了无人艇与船载端组合的固定断面测量系统,同时研究了该系统的硬件设计部分：信息采集、信息处理、信息传输。结合应用环境和无线网络技术,设计了本系统的控制逻辑架构,并阐述了系统的功能,最后展望后续的研究方向和需解决的问题。     

初始缺陷对不同深度载人潜水器耐压球壳极限承载力的影响

大深度载人潜水器耐压壳是保证其完成预定功能的最基本部件,研究初始几何缺陷,其中包括弹性屈曲模态缺陷、局部缺陷、整体圆度偏差和壳板厚度偏差,对不同深度载人潜水器耐压壳体承载力的影响乃是极其必要的。通过对不同深度潜水器的有限元分析,得出了不同深度耐压壳体受初始缺陷影响的曲线,可以确认缺陷范围处于临界弧长时结构的承载力最弱。     

海军舰载无人机的现状及其发展趋势

介绍了目前美国、以色列、加拿大等国的舰载无人机的发展现状、主要机型及其性能参数等，阐述了舰载无人机在现代海战中的作用以及未来的发展趋势。