NIF gets a lift through high-tech transporters
If the Enterprise, Voyager and Defiant are moving about you and you’re not lost in space on the set of a "Star Trek" television show, you must be in the laser bay of the National Ignition Facility (NIF). That’s where three vehicles carry ultra clean canisters used to transport phone-booth-sized optical assemblies (the Line Replaceable Units, LRUs) and install them in the NIF laser system.
Made by AGV Products Inc. of Charlotte, N.C., these transporters are high-tech and highly intelligent forklifts. Guided by a computer-controlled laser, they each weigh 29,000 pounds and can carry a canister LRUs weighing as much as 8,000 pounds. The transporters position the canisters, docking them within one millimeter and one-tenth of a degree rotation, very tight tolerances. The laser-guided transporters are able to move their forks front and back, side to side, and to rotate them on an angle, allowing them to insert the canisters into the Beampath Infrastructure System in the NIF.
The most complex automated guided vehicles ever built are bright yellow with red trim. The battery powered transporters maneuver about NIF like graceful sea lions gliding among the coral reefs. "They can also move sideways, much like a land crab," says Ray Abounader, lead Engineering Technician for the transporters.
Another special feature of each laser-guided transporter is that it can supply AC (alternating current) power to the canisters it carries. The vehicles are completely electric because electrical actuators are cleaner than hydraulics. The vehicles also carry their own utilities — compressed air, vacuum system, and "clean air" gas. The latter is used to purge the environment in these mini clean room canisters being transported and to drive some of the pneumatics in the canisters.
The transporters also need power to open their lids and insert their LRUs into NIF. "There is constant communication between the transporter’s computer control system and the canister’s computer control system," says Steve Yakuma, lead engineer for NIF’s Transport and Handling Group. One Traffic Management Computer controls the motion of all three transporters in the high bay to maximize efficiency.
The transporters carry canisters used to install the LRUs that are a variety of shapes and sizes. Inside the canisters are amplifier glass slab assemblies, flashlamp assemblies, mirrors, and other optical assemblies.
The Transport & Handling Group designed and oversaw the fabrication of the transporters and canisters and now they’re conducting tests on the NIF site intended to demonstrate that the systems are meeting their functional and cleanliness requirements prior to installing LRU’s next year.
"Our goal is to put the equipment, as well as the installation team, through its paces and show that we’re ready to go " says Gina Bonanno, associate project manager for NIF Assembly, Installation and Refurbishment.
"By testing in the field we are encountering things that might not be identified in a test environment. This gives us the opportunity to address issues early, prior to beginning the installation process. The results to date are very encouraging, we’re demonstrating that the systems are working as designed," says Bonanno.
The LRUs are built in the Optics Assembly Building, a Class 100 clean room (no more than 100 particles greater in size than five microns per cubic foot of air). "Once the LRUs are installed in the clean canister, they can be transported and inserted into the clean NIF beamlines," says Bonanno.
How it all began
Three years ago, AGV Products won the bid to create the unique forklifts and began working with LLNL engineers to custom design the biggest, cleanest robots necessary to transport and install the LRUs that comprise NIF.
The first transporter, Enterprise, was built and tested and resulted in a few improvements in the second and third transporters, Voyager and Defiant.
AGV Products, Inc. builds automated guide vehicles (AGVs) for a range of applications and is the only supplier of three guidance systems — laser, inertial and wire — according to Matt Herrstromer, president of AGV Products, Inc. Automated guide vehicles are used by General Motors to build trucks and by Boeing to build airplane wings.
A sign in the high bay of Bldg. 432, where the laser-guided transporters are tested, proclaims, "NIF Operations, to Ignite and Beyond." The laser-guided transporters may not reach "to infinity and beyond," as the character Buzz Lightyear proclaims in the children’s movie "Toy Story." However, the transporters are playing a key role in cleanly installing the optics that comprise NIF, and this powerful laser system is designed to ignite its targets and provide scientists with knowledge beyond what we know today regarding the evolution of our sun and the stars.