Enabling automated facility maintenance from articulated robot Collision-Free designs

Key challenges found in some facilities maintenance (FM) operations include the dependency on placing sophisticated workers in undesirable working conditions that could make them susceptible to accidents. Robot-assisted in-situ facilities maintenance represents new opportunities by assisting human operators when exposed to harsh environments. However, given the complexities and potential varieties of advanced robotic machinery available for use in facility maintenance workplaces in the future, there is still a legitimate risk of collisions between future robotic systems and the facility structure during the robot-assisted processes. This paper proposes and tests a simulation-based collision-free design method for future facilities that may be benefited from a robot-assisted FM process. At the most fundamental level, we consider interactions between the articulated manipulator (robot) and the surrounding facility structure. Inverse Kinematics (IK) and game engines are used to simulate the possible collisions between a given robot and the parameterized facility layout. To account for the uncertainty about the kinematic specifications of the future robotic machinery, a Monte Carlo method is used to model unique priority circumstances for each joint on the articulated manipulator. The simulation result, presented as the robot work zone envelope, is then used to estimate the collision probability given a certain design parameter, and the corresponding optimal design that balances the initial construction cost and the FM costs. The method is assessed for identifying a 3D spatial collision probability cloud within reach of a 7 DOF articulated manipulator that is marginally positioned within a pressure valve piping facility. These insights can provide future facility designers, managers, and equipment operators with a quick and flexible 3D spatial collision probability indicator to better design the facility and proximity limitations of any articulated manipulator positioned throughout a confined space for future robot-assisted FM processes.     

国产平台下可靠文件传输软件的设计及实现

在国产自主可控平台加速推广的当下,为实现文件在测控数据传输网不同软硬件平台之间的可靠、快速传输,本文根据相关技术规范,基于文件交换协议(File Exchange Protocol,简称FXP协议),设计并实现功能完备、运行稳定的可靠文件传输软件。软件具备模块化、可移植、基于TCP协议满足用户可靠性需求、基于UDP协议满足用户传输效率需求、兼容不同软硬件平台等的功能特点,并具备满足安全编程需求的软件特性,立足核心代码设计、验证,对软件功能和稳定运行两个方面做了进一步的改良和提升,以满足跨不同软硬件平台稳定运行、恶劣网络环境中可靠传输、畅通网络环境中尽力快速传输的新要求。     

海军舰艇信息装备通用测试平台设计

结合目前新型舰载信息装备保障需求,从舰艇信息装备系统化、体系化发展要求出发,以信息装备保障能力建设为中心,基于开放式综合诊断系统工程方法,从能力需求、功能、结构、技术、接口和标准等方面进行综合论证,提出舰艇信息装备通用测试平台的总体思路、软硬件结构框架、关键技术途径,对提高舰艇信息装备维修保障系统的系列化、通用化、综合化和模块组合化水平,具有较大的参考价值。     

基于分层分域的战术互联网网络架构与关键技术研究

未来战场作战模式由传统的以“平台”为中心转变为以“网络”为中心,战术互联网已成为战场的“神经系统”,它连接了战场的各作战单元要素之间并实现了信息共享和无缝连接,其网络架构是其主要能力实现的基础,它对保障战场通信网络稳定、可靠、高效的通信服务起到了至关重要的作用。美军战术互联网(如美军联合战术通信系统(JTRS)、战术级作战人员信息网(WIN-T)等)网络架构均采用了混合式架构,本文梳理分析了战术互联网发展现状,针对影响战术互联网主要性能的体系结构提出了分层分域的网络架构,即Mesh+Ad-hoc的体系架构,并对该架构下的关键技术进行了深入研究,分层分域的网络架构能够更好的提升战术互联网整体鲁棒性和抗毁性,网络的运行效率和管理能力,更加适合于未来复杂多变的战场环境。     

基于K Framework的向量化机器学习指令语义形式化

ARM针对ARMv8.1-M微处理器架构推出基于M-Profile向量化扩展方案的技术,并命名为ARM Helium,声明能为ARM Cortex-M处理器提升达15倍的机器学习性能.随着物联网的高速发展,微处理器指令执行正确性尤为重要.指令集的官方手册作为芯片模拟程序,片上应用程序开发的依据,是程序正确性基本保障.主要介绍利用可执行语义框架K Framework对ARMv8.1-M官方参考手册中向量化机器学习指令的语义正确性研究.基于ARMv8.1-M的官方参考手册自动提取指令集中描述向量化机器学习指令执行过程的伪代码,并将其转换为形式化语义转换规则.通过K Framework提供的可执行框架利用测试用例,验证机器学习指令算数运算执行的正确性.     

Elsa:一种面向跨区域架构的无协调分布式键值存储系统

作为具备高性能和高可伸缩性的分布式存储解决方案,键值存储系统近年来被广泛采用,例如Redis、MongoDB、Cassandra等.分布式存储系统中广泛使用的多副本机制一方面提高了系统吞吐量和可靠性,但同时也增加了系统协调和副本一致性的额外开销.对于跨域分布式系统来说,远距离的副本协调开销甚至可能成为系统的性能瓶颈,降低系统的可用性和吞吐量.提出分布式键值存储系统Elsa,这是一种面向跨区域架构的无协调键值存储系统. Elsa在保证高性能和高可拓展性的基础上,采用无冲突备份数据结构(CRDT)技术来无协调的保证副本间的强最终一致性,降低了系统节点间的协调开销.在阿里云上构建了跨4数据中心8节点的跨区域分布式环境,进行了大规模分布式性能对比实验,实验结果表明:在跨域的分布式环境下,对于高并发争用的负载, Elsa系统的性能具备明显的优势,最高达到MongoDB集群的7.37倍, Cassandra集群的1.62倍.     

基于程序模块化建模的智慧电站一体化平台构建

为实现在智慧电站高度一体化融合的同时,提高电站报警响应时效性和准确性,开展基于程序模块化建模的智慧电站一体化平台构建。通过电子式互感器选型、全站智能组件装置整合等硬件设计和基于程序模块化建模的三维一体化信息模型构建、电站门禁管理与人员轨迹跟踪、电站危险源识别与动态预警等软件设计,提出一种全新的智慧电站一体化平台。通过将新的平台应用到某电站火电厂中,验证了该平台能够实现对电站异常故障问题的快速响应,并保证误报警次数始终为0,在促进智慧电站安全性不断提升的同时,实现高度一体化融合。     

基于数字孪生的虚拟仿真系统研究与应用

为解决全实物平台开发环境搭建困难、不便于测试与维护等问题,在研究PowerPC 处理器的实时嵌入式开发的基础上,采用数字孪生技术的设计思想,完成了一种拥有故障模拟与注入、协同仿真与模块化编程等功能的超实时虚拟仿真系统;提出了一种全数字仿真系统的设计与实现方法,基于数字孪生技术把硬件主板上的处理器以及外围设备虚拟化,集成到数字模型当中;各模型之间相互协同控制,实现CPU控制外部设备与动力学模型等设备之间的通信,以及数据收发、内存读写、串口输出等行为,最终实现与物理设备相同的功能;另外,采用了虚实结合的方法验证了运行结果的准确性,加快了软件执行效率,便于快速全面的系统开发与测试,从而更好地运用到各个领域当中。     

典型半潜式平台结构的微振子捕能特性研究北大核心CSCD

半潜式平台在海洋资源开发领域应用前景广阔,但存在平台设备能源供给不足的问题。本研究把常见的半潜式平台简化为三种典型的浮式基础,将波浪能发电装置集成至浮式基础,建立浮式基础与浮子耦合的运动方程,利用水动力仿真软件AQWA开展数值模拟和参数化分析,获得了波浪方向、浮式基础的截面形状、浮子直径以及浮子与浮式基础间距等因素对浮子捕能特性的影响规律。结果表明,四棱柱浮式基础在特定波浪方向下能够增强微阵列浮子的捕能效果,三棱柱浮式基础使微阵列浮子更好地适应各个方向的波浪激励,圆柱浮式基础以遮蔽效应为主,较大程度上减弱了浮子的捕能特性;不同波浪方向对四棱柱浮式基础、三棱柱浮式基础周围的浮子影响较大,而对基于圆柱浮式基础的微阵列浮子影响不大;通过增加浮子的直径以及浮子距圆柱浮式基础的距离,能够有效提高微阵列浮子平均输出功率。本研究可为半潜式平台与波浪能发电装置的集成提供参考。     

Study on the Propagation Law of Shock Wave Pressure in Tunnels with Different Materials

The propagation of shock wave pressure in the tunnel is greatly affected by the tunnel structure, shape, material and other factors, and there are great differences in the propagation law of shock wave pressure in different kinds of tunnels. In order to study the propagation law of shock wave pressure in tunnels with different mate-rials, taking the long straight tunnel with the square section as an example, the AUTODYN software is used to simulate the explosion of TNT in the concrete, steel and granite tunnel, and study on the variation law of shock wave pressure in tunnels with different materials. By using dimensional analysis and combined with the results of numerical simulation, a mathematical model of the propagation law of shock wave pressure in the tunnel is established, and the effectiveness of the mathematical model is verified by making the explosion test of the warhead in the reinforce concrete tunnel. The results show that the same mass of TNT explodes in the tunnel with different materials, and the shock wave overpressure peak at the same measuring point is approximate in the near field. However, there is a significant difference in the middle-far fields from the explosion center, the shock wave overpressure peak in the steel tunnel is 20.76% and 34.82% higher than that of the concrete and the granite tunnel respectively, and the shock wave overpressure peak in the concrete tunnel is 24.91% higher than that in the granite tunnel. Through the experimental verification, getting the result that the maximum relative deviation between the measured value and the calculated value of the shock wave overpressure peak is 11.85%. Therefore, it is proved that the mathematical model can be used to predict the shock wave overpressure peak in the tunnel with different materials, and it can provide some reference for the power evaluation of warhead explosion in the tunnel.