一种基于RS—485网络的集散型控制系统

从系统构成和通信软件两方面介绍了一种基于RS-485网络的集散型控制系统。该系统的RS-485网络由1台工控机和10台可编程控制器构成。工控机通过RS-485网络控制10台独立的3自由度数控液压小车。本文提出了一种RS-485网络通信协议。

应用于HIRFL-CSR中的RS485通讯路由器

本文介绍了为适应HIRFL-CSR(兰州重离子加速器冷却储存环)工程自动化控制现场的通信要求而自主研发的一种通信设备,以及系统硬件电路设计、控制软件设计、工作方式和特点。此设备可快速组建RS485通信网络并且接入以太网,兼容Ethernet、RS232和RS485通信标准协议,特别是增加了光纤接口方便地接入工业光纤通信网络,进一步扩展了其使用范围。此设备在HIRFL-CSR加速器和储存环控制系统中被广泛使用,在使用中表明可满足系统自动控制通信要求。此设备具有实现简单、易于维护、可扩展性好及成本低廉等特点,在其它自动化工业控制领域也有一定的推广空间。

加速器控制系统中RS485总线的以太网接入

提出了在加速器控制系统中采用ATmega128和RTL8019AS廉价和高效地实现RS485总线的以太网接入的实现方法。该模块装入了以ATmega128为硬件平台的嵌入式Linux操作系统,它支持TCP/IP协议。根据加速器控制的现场需求,可以很方便地编写用浏览器或组件访问的应用程序。

BabelFuse data fusion unit with precision wireless clock synchronisation

A significant issue encountered when fusing data received from multiple sensors is the accuracy of the timestamp associated with each piece of data. This is particularly important in applications such as Simultaneous Localisation and Mapping (SLAM) where vehicle velocity forms an important part of the mapping algorithms; on fastmoving vehicles, even millisecond inconsistencies in data timestamping can produce errors which need to be compensated for. The timestamping problem is compounded in a robot swarm environment due to the use of non-deterministic readily-available hardware (such as 802.11-based wireless) and inaccurate clock synchronisation protocols (such as Network Time Protocol (NTP)). As a result, the synchronisation of the clocks between robots can be out by tens-to-hundreds of milliseconds making correlation of data difficult and preventing the possibility of the units performing synchronised actions such as triggering cameras or intricate swarm manoeuvres. In this thesis, a complete data fusion unit is designed, implemented and tested. The unit, named BabelFuse, is able to accept sensor data from a number of low-speed communication buses (such as RS232, RS485 and CAN Bus) and also timestamp events that occur on General Purpose Input/Output (GPIO) pins referencing a submillisecondaccurate wirelessly-distributed "global" clock signal. In addition to its timestamping capabilities, it can also be used to trigger an attached camera at a predefined start time and frame rate. This functionality enables the creation of a wirelessly-synchronised distributed image acquisition system over a large geographic area; a real world application for this functionality is the creation of a platform to facilitate wirelessly-distributed 3D stereoscopic vision. A ‘best-practice’ design methodology is adopted within the project to ensure the final system operates according to its requirements. Initially, requirements are generated from which a high-level architecture is distilled. This architecture is then converted into a hardware specification and low-level design, which is then manufactured. The manufactured hardware is then verified to ensure it operates as designed and firmware and Linux Operating System (OS) drivers are written to provide the features and connectivity required of the system. Finally, integration testing is performed to ensure the unit functions as per its requirements. The BabelFuse System comprises of a single Grand Master unit which is responsible for maintaining the absolute value of the "global" clock. Slave nodes then determine their local clock o.set from that of the Grand Master via synchronisation events which occur multiple times per-second. The mechanism used for synchronising the clocks between the boards wirelessly makes use of specific hardware and a firmware protocol based on elements of the IEEE-1588 Precision Time Protocol (PTP). With the key requirement of the system being submillisecond-accurate clock synchronisation (as a basis for timestamping and camera triggering), automated testing is carried out to monitor the o.sets between each Slave and the Grand Master over time. A common strobe pulse is also sent to each unit for timestamping; the correlation between the timestamps of the di.erent units is used to validate the clock o.set results. Analysis of the automated test results show that the BabelFuse units are almost threemagnitudes more accurate than their requirement; clocks of the Slave and Grand Master units do not di.er by more than three microseconds over a running time of six hours and the mean clock o.set of Slaves to the Grand Master is less-than one microsecond. The common strobe pulse used to verify the clock o.set data yields a positive result with a maximum variation between units of less-than two microseconds and a mean value of less-than one microsecond. The camera triggering functionality is verified by connecting the trigger pulse output of each board to a four-channel digital oscilloscope and setting each unit to output a 100Hz periodic pulse with a common start time. The resulting waveform shows a maximum variation between the rising-edges of the pulses of approximately 39¥ìs, well below its target of 1ms.

基于S3C4510B的网关设计及其应用

本文简要介绍了采用S3C4510B ARM7微处理器设计网关的方法。S3C4510B是一款基于ARM7TDMI内核的32/16位RISC微处理器,采用免费的uClinux作为操作系统,支持多任务、FTP服务和TELNET服务。采用该模块可以实现工业现场总线RS485和以太网的高速数据协议转换。构建高速的DCS系统。

应用于HIRFL-CSR控制系统中的光纤通信路由器

介绍了专门针对国家重大科学工程HIRFL-CSR控制要求而设计开发的光纤通信路由器。包括设计原理、硬件组成及应用范围。该光纤路由器具备RS232、RS485、标准以太网接口和光纤接口,可建立上述接口设备与光纤接口设备的光纤通讯网络。在工程中应用这种交换机解决了通信干扰等问题,满足了工程控制要求。

电子加速器调压器自控系统

为满足我所电子加速器的控制要求而自主研发了调压器控制系统。该系统的设计包括系统硬件设计、电路设计、工控机和单片机控制软件设计。控制功能模块采用RS232和RS485通信接口,可以根据需要选装光纤接口建立工业光纤通讯网络,进一步扩展使用范围并提高通讯系统的可靠性。实际应用表明,系统在无人值守情况下可自行调整并稳定调压器输出电压,可满足电子加速器调压器的精确控制和自动控制要求。该系统依据通用设计原则,具备实现简单、易于维护、可扩展性好及成本低廉等特点,在其他工业控制自动化领域也有一定的应用价值。

两种在HIRFL-CSR中使用的光纤通信适配器

介绍了两种针对HIRFL-CSR控制特点,自主开发设计的光纤通信适配器。包括设计思路、工作原理、硬件组成及应用范围。如何利用这两种光纤适配器远程控制具备RS232或RS485接口的仪器设备。在工程中应用这两种适配器和光纤替代RS485总线解决了通信干扰问题,满足了工程控制要求。

HIRFL前端智能控制模块

介绍了兰州重离子加速器(HIRFL)控制中采用的前端智能控制模块。该模块实现了对现场设备的控制和处理,使设备的远程控制方便,稳定和可靠。

嵌入式微机在控制系统中的应用

介绍了采用嵌入式微机SC-12和USB接口芯片FT245BM的智能控制终端,它具有3种灵活的数据接口方式:以太网、USB和RS485串行口。通过以太网连接可以实现灵活的远程数据获取与控制;通过USB串口总线,可以方便地进行现场数据的存取和设备的调试;而通过RS485总线可以使得一个嵌入式微机SC-12与40个挂接在总线上的控制模块进行通讯。

HIRFL-CSR真空控制系统的设计及其应用

介绍了以微控制器MSP430F149为核心设计的真空控制模块,给出了在HIRFL-CSR真空控制系统中的硬件电路和软件程序。通过RS485总线和Intranet实现了对模块连接的各种真空设备的实时远程测控。

RS-485总线在CSR控制系统中的应用

该文介绍一种能利用RS 485总线标准,采用自定义串行通信协议,实现CSR控制子系统中的总线通讯的方法。并给出总线硬件电路和相应的软件实现流程图。

基于MSP430F149单片机的真空远程控制系统

介绍了通过RS485总线和Intranet网络来实现对远程真空系统控制模块VAC400的控制和监测,并给出软件的C程序实现和部分硬件功能模块的程序流程图。系统控制模块VAC400采用TI公司的MSP430F149混合信号处理器,具有超低功耗的高集成度等优点。利用它构建的控制网络功能强大、结构简单、可靠性高、抗干扰能力强、一般不需扩展外围器件。系统适合对现场设备的远距离监测与控制。

总线控制器的设计及其在CSR控制系统中的应用

HIRFL-CSR(兰州重离子冷却储存环)是国家“九五”重大科学工程之一。CSR控制系统是保证CSR正常运行的重要环节。这是一个基于以太网的分布式控制系统，它由两部分组成：总体控制服务器系统和前端控制服务器系统。 本文介绍了应用于CSR前端控制系统中的嵌入式总线控制器。首先介绍了嵌入式总线控制器的硬件设计方案。系统以32位高速双以太网处理器JUPITER为核心。JUPITER是一款低成本、高性能、建立在以太网系统基础之上的处理器。该系统的外阴电路主要包括存储模块、接日模块、总线控制模块。接口模块有RS485、RS232和网络接口电路。其次论述了嵌入式操作系统uClinux的体系结构以及uClinux与标准Linux的不同之处。论文从uClinux的内核结构出发，讨论了源代码的组织结构，概括分析了uClinuxlj勺内存管理、进程管理。最后介绍了uClinujx统的移植方法和应用实现。uClinux移植主要包括引导装载程序、uClinux内核和文件系统三个部分。在引导装载程序的移植过程中，论文重点给出了一种固化引导装载程序的方法；在uClinux内核移植中，讨沦了交叉编译环境l为建立和uClinux内核配置方法，总结了uClinux内核移植的层次结构和具体的移植过程。沦文通过对嵌入式处理器的分析，以及对嵌入式操作系统移植的探讨，展示了嵌入式系统开发的核心技术，对眠入系统的开发应用具有一定的实际意义。