AFRL computer guides Mars rovers

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KIRTLAND AIR FORCE BASE, N.M. (AFPN) --  Radiation-resistant computers Air Force Research Laboratory experts here developed helped steer one of NASA's Mars exploration rovers to a safe landing on the red planet Jan. 4.

The AFRL's Rad6000 32-bit microprocessors, manufactured for the Air Force by BAE systems, controlled the spacecraft during its flight from Earth, said Creigh Gordon, an AFRL space vehicles directorate engineer.

The tiny microchips also direct the rovers, named Spirit and Opportunity, as they move about the planet searching for signs that water might once have existed on our neighbor.

"NASA chose AFRL microprocessors because they are proven reliable, rugged and fully compatible with their systems," Mr. Gordon said.

These computers can withstand the harsh radiation environment of space and operate reliably during long-term missions, he said. They control all data stream telemetry between the spacecraft and controllers on the ground.

The Rad6000 was not only the world's first radiation-hardened 32-bit microprocessor; it was also the most complex, containing more than 1 million transistors -- and transistors run the show, Mr Gordon said.

Like neural connections in the human brain, transistors inside computer chips help manage the flow of electrical energy by directing it through a maze of silicon-based circuits, he said. Transistors act like switches at electronic junctions to speed electrons to their intended destinations so spacecraft and rover functions can be performed.

Constant bombardment by radiation generates unwanted electrical charges inside transistors. Overcharged transistors shut down, and failed electronics mean dead missions and the loss of hundreds of millions of dollars, Mr. Gordon said..

"Much of AFRL's work in electronic spacecraft components prevents such losses," Mr. Gordon said. "Through our efforts within the space vehicles directorate, the Air Force has made significant investments into radiation hardening fabrication technologies and the space electronics based on them. Contractors such as BAE Systems and others now have the ability to manufacture such devices, which results in better products for us, NASA, the Defense Department, as well as the commercial customer."

Before AFRL researchers stepped in a few years ago, Defense Department and NASA officials paid $50 million to $100 million for each processor in development and manufacturing costs, Mr. Gordon said. Now the price of a typical processing module dropped to between $500,000 and $2 million and is available as off-the-shelf hardware.

As a direct result, microprocessor performance has improved a hundredfold, he said.

"That's an additional value of a military laboratory helping to transform and transfer technology to military and civilian users-it maximizes taxpayer investment," Mr. Gordon said. "By creating new circuit designs and the processes by which they are constructed, using different materials, and by building-in safeguards such as back-up subsystems, the Air Force-industry team has also significantly increased the life span for spacecraft missions by making electronic systems such as microprocessors more resilient to the catastrophic effects of radiation."

More than 60 Air Force, Defense Department, NASA and commercial space systems are now using this technology and more than 90 percent of satellites launched today rely on radiation-hardened processors developed here. (Courtesy of Air Force Materiel Command News Service)