LLNL, Livermore, California, USA
The Advanced Radiographic Capability (ARC) currently under development for the National Ignition Facility (NIF) will provide short (1-50 picoseconds) ultra high power (>1 Petawatt) laser pulses used for a variety of diagnostic purposes on NIF ranging from a high energy x-ray pulse source for backlighter imaging to an experimental platform for fast-ignition. A single NIF Quad (4 beams) is being upgraded to support experimentally driven, autonomous operations using either ARC or existing NIF pulses. Using its own seed oscillator, ARC generates short, wide bandwidth pulses that propagate down the existing NIF beamlines for amplification before being redirected through large aperture gratings that perform chirped pulse compression, generating a series of high-intensity pulses within the target chamber. This significant effort to integrate the ARC adds 40% additional control points to the existing NIF Quad and will be deployed in several phases over the coming year. This talk discusses some new unique ARC software controls used for short pulse operation on NIF and integration techniques being used to expedite deployment of this new diagnostic.
LLNL, Livermore, California, USA
The Integrated Computer Control System (ICCS) at the National Ignition Facility (NIF) uses Front-End Processors (FEP) controlling over 60,000 devices. Often device faults are not discovered until a device is needed during a shot, creating run-time errors that delay the laser shot. This paper discusses a new ICCS framework feature for FEPs to monitor devices and report its overall health, allowing for problem devices to be identified before they are needed. Each FEP has different devices and a unique definition of healthy. The ICCS software uses an object oriented approach using polymorphism so FEP’s can determine their health status and report it in a consistent way. This generic approach provides consistent GUI indication and the display of detailed information of device problems. It allows for operators to be informed quickly of faults and provides them with the information necessary to pin point and resolve issues. Operators now know before starting a shot if the control system is ready, thereby reducing time and material lost due to a failure and improving overall control system reliability and availability.
LLNL, Livermore, California, USA
Network packet inspection using port mirroring provides the ultimate tool for understanding complex behaviors in large distributed control systems. The timestamped captures of network packets embody the full spectrum of protocol layers and uncover intricate and surprising interactions. No other tool is capable of penetrating through the layers of software and hardware abstractions to allow the researcher to analyze an integrated system composed of various operating systems, closed-source embedded controllers, software libraries and middleware. Being completely passive, the packet inspection does not modify the timings or behaviors. The completeness and fine resolution of the network captures present an analysis challenge, due to huge data volumes and difficulty of determining what constitutes the signal and noise in each situation. We discuss the development of a deep packet inspection toolchain and application of the R language for data mining and visualization. We present case studies demonstrating off-normal analysis in a distributed real-time control system. In each case, the toolkit pinpointed the problem root cause which had escaped traditional software debugging techniques.