Tell your computer to shut up!
Posted on 01/23/2004 5:49:06 PM PST by ambrose
Computers Are Tougher to Fix on Mars
By MATTHEW FORDAHL, AP Technology Writer
SAN JOSE, Calif. - Whether on a desktop on Earth or roving about Mars, modern computers share the basic building blocks - and can run into the same problems.
But glitches are much easier to diagnose and repair on Earth than on another planet. It's a challenge now faced by NASA (news - web sites) engineers as they try to find out why the Mars rover Spirit has rebooted its computer 60 times and sent back irregular communications since Wednesday.
On Earth, problems can be fixed by hitting the power button or, at most, replacing a bad part. In space, it's not so easy: Remotely hitting the reset button is possible but swapping out hardware is out of the question.
The systems aboard the Mars rovers are specially designed for the rigors of space, from launch to landing and beyond. Software is built so updates can be remotely beamed from Earth.
The rovers' computers don't run Microsoft Windows. They rely on an operating system called VxWorks from Alameda, Calif.-based Wind River Systems Inc., which has provided the software brains for Mars Pathfinder, Deep Space One and other spacecraft.
"The space community in general is very conservative and wants to make sure that their $500 million mission is not jeopardized by software that hasn't gone through the rigors of space qualification," said Vic Scuderi, manager of space programs at BAE Systems in Manassas, Va.
At the heart of each Mars rover is a computer on a single board called the RAD6000. Its circuits are hardened to absorb radiation and qualified for space flight. Otherwise, charged particles would quickly ruin the sensitive hardware.
The system built by BAE has been used in other spacecraft, including Pathfinder, the Mars Odyssey orbiter and Stardust, which earlier this month successfully swooped past the comet Wild 2.
In fact, there are 145 RAD6000s running on 77 satellites in space.
"It's quite a well-heeled computer to be used in spacecraft," Scuderi said.
The microprocessor belongs to the PowerPC family, a version of which is still used today in Apple Computer Inc.'s Macintosh (news - web sites) computers as well as corporate servers and workstations.
The chip was designed in the early 1990s by International Business Machines Corp., when the BAE unit was part of IBM's Federal Systems Co. The IBM division, working with the Air Force Research Lab, developed the radiation-hardened version.
Compared to today's Earth-bound PCs, the RAD6000 seems like an underperformer. Its 1.1 million-transistor processor runs as fast as 25 megahertz, compared to 3.2 gigahertz for today's top Intel Pentium 4, which has 55 million transistors.
But the RAD6000 had 10 times better performance over previous processors qualified for space. It reduced the number of boards from five to one. And it reduced the weight and power required for the computer by five fold.
The RAD6000 has no moving parts, so there's no hard drive for storage. Instead, data are kept in 128 megabytes of random access memory.
Another sign that the RAD6000 is not meant for home computers: Each costs between $200,000 and $300,000.
DUH! Ping...
Tell your computer to shut up!
Nonsense. Just ask anyone at Dell. Why, they can have Sanjay...er...I mean "Steve" in the consumer tech support division in India call up the rover and walk it through several scripted reboot procedures just like the do here. It's more cost effective. ;)
So are washing machines.
I bet that technician will tell them to take the image disk and completely wipe out all the data on the hard drive that wasn't backed up and restore the computer to its factory state. ;(
"My name is Paul. First we are holding down the control key while simultaneously depressing and holding the Shift and Alt. Then we are going to the Martian Quicky Mart for a Squishy while we are waiting for the whole mess to come back online!"
Get a lod of this stat: Mean Time Between Failures (MTBF) Greater than 375K hours
wow!
Well, *there's* the problem... (Now how do I ping all the Mac apostles to this thread so I can properly tweak them?) /smirk.
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