5,547 research outputs found
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National Ignition Facility integrated computer control system
The NIF design team is developing the Integrated Computer Control System (ICCS), which is based on an object-oriented software framework applicable to event-driven control systems. The framework provides an open, extensible architecture that is sufficiently abstract to construct future mission-critical control systems. The ICCS will become operational when the first 8 out of 192 beams are activated in mid 2000. The ICCS consists of 300 front-end processors attached to 60,000 control points coordinated by a supervisory system. Computers running either Solaris or VxWorks are networked over a hybrid configuration of switched fast Ethernet and asynchronous transfer mode (ATM). ATM carries digital motion video from sensors to operator consoles. Supervisory software is constructed by extending the reusable framework components for each specific application. The framework incorporates services for database persistence, system configuration, graphical user interface, status monitoring, event logging, scripting language, alert management, and access control. More than twenty collaborating software applications are derived from the common framework. The framework is interoperable among different kinds of computers and functions as a plug-in software bus by leveraging a common object request brokering architecture (CORBA). CORBA transparently distributes the software objects across the network. Because of the pivotal role played, CORBA was tested to ensure adequate performance
MiniCPS: A toolkit for security research on CPS Networks
In recent years, tremendous effort has been spent to modernizing
communication infrastructure in Cyber-Physical Systems (CPS) such as Industrial
Control Systems (ICS) and related Supervisory Control and Data Acquisition
(SCADA) systems. While a great amount of research has been conducted on network
security of office and home networks, recently the security of CPS and related
systems has gained a lot of attention. Unfortunately, real-world CPS are often
not open to security researchers, and as a result very few reference systems
and topologies are available. In this work, we present MiniCPS, a CPS
simulation toolbox intended to alleviate this problem. The goal of MiniCPS is
to create an extensible, reproducible research environment targeted to
communications and physical-layer interactions in CPS. MiniCPS builds on
Mininet to provide lightweight real-time network emulation, and extends Mininet
with tools to simulate typical CPS components such as programmable logic
controllers, which use industrial protocols (Ethernet/IP, Modbus/TCP). In
addition, MiniCPS defines a simple API to enable physical-layer interaction
simulation. In this work, we demonstrate applications of MiniCPS in two example
scenarios, and show how MiniCPS can be used to develop attacks and defenses
that are directly applicable to real systems.Comment: 8 pages, 6 figures, 1 code listin
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Integrated Dynamic Facade Control with an Agent-based Architecture for Commercial Buildings
Dynamic façades have significant technical potential to minimize heating, cooling, and lighting energy use and peak electric demand in the perimeter zone of commercial buildings, but the performance of these systems is reliant on being able to balance complex trade-offs between solar control, daylight admission, comfort, and view over the life of the installation. As the context for controllable energy-efficiency technologies grows more complex with the increased use of intermittent renewable energy resources on the grid, it has become increasingly important to look ahead towards more advanced approaches to integrated systems control in order to achieve optimum life-cycle performance at a lower cost. This study examines the feasibility of a model predictive control system for low-cost autonomous dynamic façades. A system architecture designed around lightweight, simple agents is proposed. The architecture accommodates whole building and grid level demands through its modular, hierarchical approach. Automatically-generated models for computing window heat gains, daylight illuminance, and discomfort glare are described. The open source Modelica and JModelica software tools were used to determine the optimum state of control given inputs of window heat gains and lighting loads for a 24-hour optimization horizon. Penalty functions for glare and view/ daylight quality were implemented as constraints. The control system was tested on a low-power controller (1.4 GHz single core with 2 GB of RAM) to evaluate feasibility. The target platform is a low-cost ($35/unit) embedded controller with 1.2 GHz dual-core cpu and 1 GB of RAM. Configuration and commissioning of the curtainwall unit was designed to be largely plug and play with minimal inputs required by the manufacturer through a web-based user interface. An example application was used to demonstrate optimal control of a three-zone electrochromic window for a south-facing zone. The overall approach was deemed to be promising. Further engineering is required to enable scalable, turnkey solutions
The CERN Detector Safety System for the LHC Experiments
The Detector Safety System (DSS), currently being developed at CERN under the
auspices of the Joint Controls Project (JCOP), will be responsible for assuring
the protection of equipment for the four LHC experiments. Thus, the DSS will
require a high degree of both availability and reliability. After evaluation of
various possible solutions, a prototype is being built based on a redundant
Siemens PLC front-end, to which the safety-critical part of the DSS task is
delegated. This is then supervised by a PVSS SCADA system via an OPC server.
The PLC front-end is capable of running autonomously and of automatically
taking predefined protective actions whenever required. The supervisory layer
provides the operator with a status display and with limited online
reconfiguration capabilities. Configuration of the code running in the PLCs
will be completely data driven via the contents of a "Configuration Database".
Thus, the DSS can easily adapt to the different and constantly evolving
requirements of the LHC experiments during their construction, commissioning
and exploitation phases.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics
(CHEP03), La Jolla, Ca, USA, March 2003, 5 pages, PDF. PSN THGT00
Development and implementation of a LabVIEW based SCADA system for a meshed multi-terminal VSC-HVDC grid scaled platform
This project is oriented to the development of a Supervisory, Control and Data Acquisition
(SCADA) software to control and supervise electrical variables from a scaled platform that
represents a meshed HVDC grid employing National Instruments hardware and LabVIEW logic
environment. The objective is to obtain real time visualization of DC and AC electrical variables
and a lossless data stream acquisition.
The acquisition system hardware elements have been configured, tested and installed on the
grid platform. The system is composed of three chassis, each inside of a VSC terminal cabinet,
with integrated Field-Programmable Gate Arrays (FPGAs), one of them connected via PCI bus
to a local processor and the rest too via Ethernet through a switch. Analogical acquisition
modules were A/D conversion takes place are inserted into the chassis. A personal computer is
used as host, screen terminal and storing space.
There are two main access modes to the FPGAs through the real time system. It has been
implemented a Scan mode VI to monitor all the grid DC signals and a faster FPGA access mode
VI to monitor one converter AC and DC values. The FPGA application consists of two tasks
running at different rates and a FIFO has been implemented to communicate between them
without data loss.
Multiple structures have been tested on the grid platform and evaluated, ensuring the
compliance of previously established specifications, such as sampling and scanning rate, screen
refreshment or possible data loss.
Additionally a turbine emulator was implemented and tested in Labview for further testing
Data communication network at the ASRM facility
The main objective of the report is to present the overall communication network structure for the Advanced Solid Rocket Motor (ASRM) facility being built at Yellow Creek near Iuka, Mississippi. This report is compiled using information received from NASA/MSFC, LMSC, AAD, and RUST Inc. As per the information gathered, the overall network structure will have one logical FDDI ring acting as a backbone for the whole complex. The buildings will be grouped into two categories viz. manufacturing critical and manufacturing non-critical. The manufacturing critical buildings will be connected via FDDI to the Operational Information System (OIS) in the main computing center in B 1000. The manufacturing non-critical buildings will be connected by 10BASE-FL to the Business Information System (BIS) in the main computing center. The workcells will be connected to the Area Supervisory Computers (ASCs) through the nearest manufacturing critical hub and one of the OIS hubs. The network structure described in this report will be the basis for simulations to be carried out next year. The Comdisco's Block Oriented Network Simulator (BONeS) will be used for the network simulation. The main aim of the simulations will be to evaluate the loading of the OIS, the BIS, the ASCs, and the network links by the traffic generated by the workstations and workcells throughout the site
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