Design and implementation of platform for embedded Ethernet control system

A platform named EMECS based on embedded Ethernet control system is implemented.A PC running Fedora 6(Linux2.6)works as a central controller.A kit running Linux 2.4 based on Samsung2410A(ARM920t core)works as a remote controller and a DC motor(ESCA P28HSL18-219/204)made by Portescap Company works as a plant.Firstly,system modeling is presented by analyzing the characteristics of Ethernet and the plant,based on a proposed delay measurement method.Secondly,implementation of the system including program and hardware is described in detail.And then the delay is measured and the control results of the system are tested in three cases with different network loads as well.The platform is proved to have flexibility of running different control algorithms and extensibility of adding nodes.Experiment results demonstrate the validity of the system.

Time-stamped predictive functional control for networked control systems with random delays

The random delays in a networked control system (NCS) degrade control performance and can even destabilize the control system.To deal with this problem,the time-stamped predictive functional control (PFC) algorithm is proposed,which generalizes the standard PFC algorithm to networked control systems with random delays.The algorithm uses the time-stamp method to estimate the control delay,predicts the future outputs based on a discrete time delay state space model,and drives the control law that applies to an NCS from the idea of a PFC algorithm.A networked control system was constructed based on TrueTime simulator,with which the time-stamped PFC algorithm was compared with the standard PFC algorithm.The response curves show that the proposed algorithm has better control performance.

Ethernet Implementation of Fault Tolerant Train Network for Entertainment and Mixed Control Traffic

This paper studies the integration of the control system and entertainment on board of train wagons. Both the control and entertainment loads are implemented on top of Gigabit Ethernet, each with a dedicated controller/server. The control load has mixed sampling periods. It is proven that this system can tolerate the failure of one controller in one wagon. In a two wagon scenario, fault tolerance at the controller level is studied, and simulation results show that the system can tolerate the failure of 3 controllers. The system is successful in meeting the packet end-to-end delay with zero packet loss in all OPNET simulated scenarios. The maximum permissible entertainment load is determined for the fault tolerant scenarios.

Evaluating the Performance of Fault-Tolerant S2A vs. In-Loop Controller Models for Ethernet-Based NCS

Two different controller-level fault-tolerant models for Ethernet-based Networked Control Systems (NCSs) are presented in this paper. These models are studied using unmodified Fast and Gigabit Ethernet. The first is an in-loop controller model while the second is a direct Sensor to Actuator (S2A) model. OMNeT++ simulations showed the success of both models in meeting system end-to-end delay and strict zero packet loss (with no over-delayed packets) requirements. It was shown in the literature that the S2A model has a lower end-to-end delay than the in-loop controller model. It will be shown here that, on the one hand, the in-loop fault-tolerant model performs better in terms of less total end-to-end delay than the S2A model in the fault-free situation. While, on the other hand, in the scenario with the failed controller(s), the S2A model was shown to have less total end-to-end delay.

Wireless Fault-Tolerant Controllers in Cascaded Industrial Workcells Using Wi-Fi and Ethernet

A Wireless Networked Control System using 802.11b is used to model fault-tolerance at the controller level of an industrial workcell. The fault-tolerance study in this paper presents the cascading of two independent workcells where each controller must be able to handle the load of both cells in case of failure of the other one. The intercommunication is completely wireless between the cells and this feature is investigated. The model incorporates unmodified 802.11b and 802.11g for communication. Sensors send sampled data to both controllers and the controllers to exchange a watchdog. The fault-free and faulty models are both simulated using OPNET Network Modeler. External interference on the critical intercommunication link is also investigated. Results of simulations are presented based on a 95% confidence analysis, guaranteeing correct system performance.

Research on OPC-based Fracturing Unit Control System

With the large-scale integration of fracturing unit’s on-site construction,traditional industrial buses are increasingly unable to meet the requirements for the quantity transmission between various equipment in large-scale fracturing units,and different models of different equipment manufacturers cannot cooperate with each other as there are“Islands of information”in the control system.This article uses industrial Ethernet as the physical medium for data transmission.In addition,different equipment manufacturers use OPC as the core technology of the fracturing unit control system network,and set up an intelligent fracturing unit control system,so that the control network can quickly,accurately,and safely control the fracturing truck control system.The sand truck control system monitors and analyzes,saves,and prints the construction data in the vehicle instrument.At the same time,the network control system uses the vehicle instrument as the core of the network.It can control fracturing vehicles from different manufacturers.The sand mixer truck performs network control,which effectively avoids incompatibilities between various equipment manufacturers at the construction site.

关于隧道内环网Controller Link和Ethernet的比较

在介质访问控制上，以太网与现场总线有本质区别。介质访问控制要求通信的实时性和确定性。确定性是指站点每次得到的网络服务间隔和时间是确定的，实时性是指网络分配给站点的服务时间和间隔可以保证站点完成它确定的任务。

基于PLC与Ethernet的饲料生产线控制系统设计

目前我国秸秆机械化加工水平低、利用成本高,造成了秸秆资源的严重浪费。为实现全自动化的饲料生产,提高生产效率,文章设计了基于西门子S7-200 SMART PLC与Ethernet通信的饲料生产线控制系统。该文重点开展了裹包生产线工艺流程设计、硬件系统选型、控制电路设计、软件系统I/O点分配和控制流程设计,实现了秸秆原料自动配比、混和搅拌、裹包贮存、现场监控、故障报警等功能。试验结果表明:此生产线可通过工控机或触摸屏全程控制配料和生产过程,智能化、自动化程度较高,满足国内畜牧业不断扩大的饲料消耗需要,适用于各类饲料生产行业。

基于Ethernet-APL的新型工业控制系统设计

两线制以太网Ethernet-APL通信技术,以其供电、高带宽、远距离、防爆设计成为目前工业领域最具潜力的现场通信技术,国内产业链正在积极推动Ethernet-APL芯片、仪表、交换机、控制系统的研发。从工业控制系统角度,提出了Ethernet-APL新型工业控制系统可能的应用场景以及与之匹配的系统架构。同时,也对该控制系统的网络负荷、实时性、网络冗余、仪表IP分配等关键技术提出了设计方案。随着该技术的推广,将会助力仪表智能化及工厂智能制造的实现。

A distributed control system for picosecond accelerator at SINAP

The picosecond accelerator (PA) is a low energy electron linear accelerator facility under commissioning, which is built for the experiment of ps level pulse radiolysis in Shanghai Institute of Applied Physics (SINAP). A practical distributed DA&C system for this facility has been developed. In view of the upgrading-ability and main-tainability of the control system and controlled devices, Advantech? distributed intelligent DA&C products are adopted into the control system. ADAM 5000/TCPs with the protocol of Modbus/TCP are employed to accomplish data acquisition and device control. The PC-compatible programmable logic controller, ADAM-5511, is also adopted to handle the interlocks and the emergency events. On the software side, the integrated software package King-view?V6.5, which friendly supports all Advantech products, has been used to develop the upper layer control logic and process the data. This paper describes the control system design and system architecture. The intelligent ADAM controllers and the software platform are also discussed in detail.

Design and implementation of ethernet passive electronic network over coax

To increase the limit of ethernet over coax （EoC） technology in the bidirectional reform of the hybrid fiber coaxial （HFC） network, an ethernet passive electronic network （EPEN） system based on Coax is proposed and experimentally demonstrated in this paper. The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network （EPON） for reduction of cost of the HFC network. As the MPCP （multi-point control protocol） is introduced in the EPEN, bandwidth control and higher efficiency can be achieved. The experimental results exhibit the throughput of system up to 100Mbps, which meet the requirements of HFC network. To improve the performance of EPEN, frequency division multiplexing （FDM） can be used for further increase of the throughput and more hardware processing modules in the future. can be implemented to enhance the capacity

Ethernet与工业控制网络

从 Ethernet的产生和特点分析 ,分析了以前 Ethernet未能应用于工业自动化的原因 ;从 Ethernet应用于工业控制领域过程监控层网络的发展趋势 ,分析了 Ethernet应用于现场总线的可行性及需要解决的关键技术难题。最后对“e网到底”应用前景进行了展望。

EtherNet/IP在工厂信息化应用前景研究

通过回顾工业控制网络的发展历史,提出了工业以太网与传统以太网技术的根本区别,简要介绍了开放式工业以太网技术EtherNet/IP的构成方式、发展和应用概况以及优势,分析了工业以太网技术蓬勃发展的深刻动力及其与工厂信息化的关系。

基于Ethernet的开放式机器人等离子熔射成形系统研究

提出了基于工业以太网(Ethernet)的机器人等离子熔射成形系统.基于Ethernet建立PC与MotomanUP-20机器人之间的通讯连接,开发了机器人控制软件,实现了PC对机器人的主机控制以及作业文件交互等功能.基于MPI(Multi-Point Interface)网络连接PC与等离子熔射设备的控制核心Siemens S7-300型PLC.最终实现了以PC机为核心,集成成形过程监控、机器人熔射路径自适应调整和机器人实时监控等子功能的开放式机器人等离子熔射成形系统,并自主开发了SprayMonitor成形过程监控软件.实验结果表明,该系统能够根据熔射皮膜温度、厚度等在线检测信息进行熔射路径智能自适应调整和加工策略自行调度,实现了等离子熔射成形与机器人运动执行的一体化控制,提高了成形系统的柔性.

Ethernet/IP在工业实时控制中应用的研究

对Ethernet/IP的协议结构进行了介绍并对其特点进行了总结 ,对以太网应用于工业控制中关键的实时性分析也作了详细阐述。

基于PLC和Ethernet的铣刨机无线测控系统设计

针对某铣刨机,研制了无线测控系统,其主要由PLC、通信模块、继电器、触摸屏、路由设备、远程终端等组成;在系统设计中,基于GE ifix环境开发了基于Ethernet的测控软件,解决了不同操作系统平台和硬件环境下的兼容问题;提出了主机掉线PLC状态自保持、无线控制与本地控制冗余和控制指令优先级划分的技术思路,实现了系统可靠运行;该系统具备本地控制与无线遥控两种控制方式,并已在该铣刨收机上得到应用,实现了平台所有操作的无线遥控,无指令丢失和误动作。

基于Ethernet的全开放工业控制网络

本文从信息发展的进程出发 ,总结了现场总线在发展中存在的问题 ,阐述了以太网进军工业自动化领域的必然性 ,说明了以太网将最终连接大多数的传感器和执行器 ,并由此形成一种基于以太网的全开放的扁平化工业控制网络结构。

关于Ethernet现场智能控制器的几点思考

阐述了Ethernet将成为主要的工业现场网络之一 ,并据此详细分析了Ethernet现场控制器的发展趋势 ,如嵌入式WEB技术将在设备管理系统中的作用、B/S与C/S的融合将成为新的应用模式和基于浏览器的监控将挑战传统组态软件等。

温室Ethernet智能控制器的设计

介绍了分布式温室控制系统中Ethernet智能控制器的软硬件设计,它采用RTL8019AS芯片接入以太网,利用TCP/IP协议实现与PC的通信,智能控制器采用模糊控制技术对温室内温湿度进行控制,取得了较好的控制效果。

Ethernet现场总线及其在水厂自动化改造中的应用

介绍了Ethernet现场总线的特点及其构建的工业控制网络平台,说明了工业以太网在水厂自动化改造中的实际应用,探讨了Ethernet现场总线控制系统设计及设备配置方法,给出了具体的结构。