Lab Working with Virtual Nuts, Bolts
New software helps Sandia construct weapons for computer simulation more quickly
By Ian Hoffman
A master modeling database is evolving for the world's most powerful weapons, and scientists say it one day could figure in the design of cars, airplanes and other complex machinery.
For years, U.S. nuclear weaponeers relied on handwritten notes and floppy disks to track changes and relationships among thousands of bomb parts. With the end of explosive testing and the emergence of powerful new computers, this antiquated system was due for an overhaul. Just pulling together the digital pieces for a computer simulation of a weapon detonating or crashing into a wall or arcing through frigid space could take months.
Last week at a Baltimore conference, Sandia National Laboratories/California unveiled a new software tool for assembling complicated parts into whole machines for the kind of virtual experiments that are routine for weapons maintenance and refurbishment.
The faster assembly speeds up the dozens of computer analyses that scientists use, for example, to judge whether a replacement part could snap loose in a fall and make a weapon more vulnerable to accidental detonation.
"Now it may take weeks instead of months," said Sandia computer scientist Robert Mariano.
As a side benefit, Sandia's software -- called SIMBA or Simulation Manager and Builder for Analysts -- records the origins of every computerized part and its connection to the whole. That helps solve two pressing problems for those responsible for the nation's nuclear arsenal.
One is retirement of the most seasoned bomb designers, those who cratered the Pacific and the Nevada with their inventions before the first President Bush suspended explosive testing in 1992. Often the best of these recorded their detailed knowledge sparingly, which is the second problem.
Older designers already are teaching their skills to a new generation, both in person and in CD-ROM tutorials. Beyond this massive archiving project, weapons scientists always have access to the "pinks," the full, documented blueprints for every weapon down to the nuts-and-bolts level.
But weaponeers still had no software to capture and record changes to the computer files that are a cornerstone of keeping decades-old weapons operable without making or testing entirely new ones. SIMBA does that.
"We were told by our analysts that when they're doing their calculations, they have Post-It notes all over the place and floppies and now Zip disks in their drawer, and it takes a long time to put all of this together," said Ken Washington, Sandia's chief of distributed information systems.
He said, "With this tool, you can take a part built by someone else at another time and another place, and hook it into your part that you need to analyze. It gives you the full pedigree for every part. And it goes everywhere the part does."
Even with the nation's fastest computers, scientists only recently got access to enough processing power to simulate accidents with detailed, full weapons in three dimensions. They slipped past that mark in the late 1990s when each of the nation's three weapons labs gained computers capable of performing more than a trillion calculations per second.
With SIMBA, scientists can make sure the computerized parts fit together realistically and more easily run simulations that, for example, predict whether a part will be crushed or a screw will shear apart in an accident, said Jay Dike, a Sandia weapons analyst.
SIMBA is designed for classified weapons research, to let scientists perform their work without breaching need-to-know barriers. But similar unclassified software, they said, could prove valuable for civilian manufacturers as they increasingly turn to 3-D computer simulations for designing new cars, plans and other complicated machinery.