HUNTSVILLE, Ala. – A Saturn-rocket-era tunnel that once was a fallout shelter is being used at Marshall Space Flight Center to test equipment that could help put men and unmanned landers on the moon.

The tunnel, more than 1,000 feet long, runs between a rocket engine test stand and a monitoring building. It is being used for experiments with a $400,000 laser guidance test program for a docking system that NASA managers hope will help the Orion crew capsule dock with a lunar landing craft before leaving Earth orbit for the moon.

“This tunnel was filled with trays floor to ceiling with these massive, thick cables – dozens of them,” said Susan Spencer, Marshall’s manager of Automated Rendezvous and Docking Projects. “Those were used to relay data from the test stand back during the 1960s. It’s something one small fiber-optic cable could do today. We cleaned those out and now have a pretty good test area” for the laser work.

Spencer said the tunnel was ideal: The laser could not be used above ground without complicated clearances from the Federal Aviation Administration “because of the worry about the laser possibly distracting a driver or pilot.”

Marshall engineers took a laser detection and ranging system, developed by Raytheon Missile Systems for the military, and mounted it on a small vehicle. Then a target was placed on a track mounted to the roof of the tunnel. For two weeks of tests in July and August, the vehicle detected and moved toward the target, said Tom Bryan, senior engineer with Marshall’s Flight Robotics Lab. “We’ve found in the past that, if we have detectors mounted to a satellite or docking port, such as the one on the space station, and by using lasers to gauge the range, then docking is very precise,” Bryan said. “We’ve demonstrated that we can move close to a satellite in orbit, and we’ve used this type of technology on tests in the past.

“The work we are doing now will refine that ability and make it usable for a crew vehicle like the Orion or an unmanned lunar lander.” Raytheon engineers are working with the National Aeronautics and Space Administration to use the laser technology help probes and manned landers navigate the boulder-strewn surface of the moon.

“This is similar to cruise missiles and other types of weapons where images are placed in the computer memory of the weapon so it can detect a target and move toward it,” said Joe Wasley, director of Raytheon’s Huntsville operations. “The major difference is that we want a vehicle to land or dock, not to attack a target.”

NASA managers hope to develop the technology so the laser system can be used with lunar maps made by the Lunar Reconnaissance Orbiter that could be stored in manned and unmanned landers, Bryan said.

“When Neil Armstrong landed the lunar module on the moon, he found the original landing site was strewn with boulders because they didn’t have accurate maps,” Bryan said. “He had to fly the lunar module around to find an appropriate place to land that wouldn’t put a boulder through the bottom of the lunar module. That used up a lot of fuel, and they were close to aborting that first landing. We don’t want to have to repeat that.”

NASA plans call for several unmanned landers to help with the construction of lunar bases, Bryan said.

“That makes this technology even more critical, because there won’t be a Neil Armstrong-type pilot to take charge effectively,” he said. “We could lose a valuable lander if a boulder crops up where we don’t expect it.”

PH END SPIRES

(Shelby G. Spires is the aerospace writer for The Huntsville (Ala.) Times. He can be contacted at shelby.spires(at)htimes.com)

2007-09-21-LASER-DOCKING

AP-NY-09-21-07 1554EDT