CORBA-Based Distributed Software Framework for the NIF Integrated Computer Control System

The National Ignition Facility (NIF), currently under construction at the Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8 Megajoule, 500-Terawatt, ultra-violet laser system together with a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. The NIF is operated by the Integrated Computer Control System (ICCS) which is a scalable, framework-based control system distributed over 800 computers throughout the NIF. The framework provides templates and services at multiple levels of abstraction for the construction of software applications that communicate via CORBA (Common Object Request Broker Architecture). Object-oriented software design patterns are implemented as templates and extended by application software. Developers extend the framework base classes to model the numerous physical control points and implement specializations of common application behaviors. An estimated 140 thousand software objects, each individually addressable through CORBA, will be active at full scale. Many of these objects have persistent configuration information stored in a database. The configuration data is used to initialize the objects at system start-up. Centralized server programs that implement events, alerts, reservations, data archival, name service, data access, and process management provide common system wide services. At the highest level, a model-driven, distributed shot automation system provides a flexible and scalable framework for automatic sequencing of work-flow for control and monitoring of NIF shots. The shot model, in conjunction with data defining the parameters and goals of an experiment, describes the steps to be performed by each subsystem in order to prepare for and fire a NIF shot. Status and usage of this distributed framework are described

Status of the National Ignition Facility and Control System

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a stadium-sized facility under construction that will contain a 192-beam, 1.8-Megajoule, 500-Terawatt, ultraviolet laser system together with a 10-meter diameter target chamber with room for multiple experimental diagnostics. NIF will be the world's largest and most energetic laser experimental system, providing a scientific center to study inertial confinement fusion (ICF) and matter at extreme energy densities and pressures. NIF's laser beams are designed to compress fusion targets to conditions required for thermonuclear burn, liberating more energy than required to initiate the fusion reactions. NIF is comprised of 24 independent bundles of 8 beams each using laser hardware that is modularized into line replaceable units such as optical assemblies, amplifiers, and multi-function sensor packages containing thousands of adjusting motors and diagnostic points. NIF is operated by the Integrated Computer Control System (ICCS) in an architecture partitioned by bundle and distributed among over 750 front-end processors and supervisory servers. Bundle control system partitions are replicated and commissioned by configuring the control database for each new bundle. NIF's automated control subsystems are built from a common object-oriented software framework based on CORBA distribution that deploys the software across the computer network and achieves interoperation between different languages and target architectures. ICCS software is approximately 80% complete with 1.1 million source lines of code delivered to the facility. NIF has successfully activated, commissioned and utilized the first four laser beams to conduct nearly 400 shots in 2003 and 2004, resulting in high quality data that could not be obtained on any other laser system. This presentation discusses NIF's early light commissioning, the status of the control system implementation and plans to complete installation of the remaining laser bundles on the path to fusion ignition

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

A prototype distributed object-oriented architecture for image-based automatic laser alignment

Designing a computer control system for the National Ignition Facility (NIF) is a complex undertaking because of the system`s large size and its distributed nature. The controls team is addressing that complexity by adopting the object-oriented programming paradigm, designing reusable software frameworks, and using the Common Object Request Broker Architecture (CORBA) for distribution. A prototype system for image-based automatic laser alignment has been developed to evaluate and gain experience with CORBA and OOP in a small distributed system. The prototype is also important in evaluating alignment concepts, image processing techniques, speed and accuracy of automatic alignment objectives for the NIF, and control hardware for aligment devices. The prototype system has met its inital objectives and provides a basis for continued development

Large distributed control system using ADA in fusion research

Construction of the National Ignition Facility laser at Lawrence Livermore National Laboratory features a large distributed control system constructed using object-oriented software engineering techniques. Control of 60,000 devices is effected using a network of some 500 computers that run software written in Ada and communicating through CORBA. The project has completed its final design review; implementation of the first of five planned increments will be delivered at the end of fiscal year 1998. Preliminary measures of the distributed controls performance confirm the design decisions reported in this paper, and the measurement and supporting simulation of full system performance continue