We have been developing the capability to characterize the high strain rate response of continuous fiber polymer composites. The data presented cover strain rates from 0/s to 3000/s. A combination of test machines and specimen geometries was investigated. Strain rates from 0 to 100/s were generated using conventional and high-speed hydraulic test machines. Strain rates from 10 to 1000/s were generated using a high-energy drop tower, and rates from 1000 to 3000/s were generated using a split Hopkinson bar. Strain rates above 100/s have only been generated for uniaxial compression. Our efforts have primarily focused on developing the high-energy drop tower for these purposes. Specimen geometries for compression include tapered cubes, one-inch tubes, and solid rods. For tension, a smaller 1.27-cm-diameter version of our 5.08-cm-diameter multiaxial test specimen was developed and has been successfully used at strain rates up to 100 per second. Fixtures were also developed for performing high strain rate shear testing and through thickness penetration studies of composite plates. The objective of these experiments is to develop dynamic material models for use in finite element design tools. This presentation will focus on the methods and results obtained from this study.

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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.

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