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GPS Transitions to New Control System
gsfprez writes "It took us a long time, but the Air Force has finally moved off of the 1970's mainframe GPS control system and is now running on a new Unix-based Control System called AEP — Architecture Evolution Plan. It's important to remember that current GPS satellites are basically solar powered iPod shuffles with atomic clocks that simply playback whatever we upload into them at a precise rate. They don't actually have any idea where they are — its the control system at Schriever Air Force Base that does. The new system will be a lot cheaper to support and modify since Sun stocks things like SATA drives - while digging up Saturday Night Fever-era DASDs isn't simple. AEP will also allow us to be ahead of the curve: we're basically good to go to fly the new IIF birds."
They finally upgraded from 1970s technology to..
..Unix. Oh.
Um.
Yay!!!
More Twoson than Cupertino
"Solar powered iPod shuffles with atomic clocks" ... is that the best metaphor they could come up with?!
how media-friendly can you get, damn....
Why not just say that they are high-precision devices that are coordinated from the ground, and that they updated the ground software to something newer and more maintainable? Why do they have to mention a completely unrelated Apple product?
*sigh*
ìì!
The system they are referring to here tracks the satellites and tells them what to say. The output will not change, just the method used to generate it.
I wonder what IBM mainframe they used. If it was an 360/370, couldn't they have just upgraded to a new IBM mainframe and kept the old software, after much much testing?
I applaud them, though, for spending the money to get this done, and get rid of all the legacy crap. It will seriously pay of in the long run, even against just upgrading the hardware. Big Old Companies still using piles of FORTRAN and COBOL should learn from this.
Which release of Unix are they moving to? Would that be an SCO Unix (System V Release 3.2) or SCO UnixWare (System V Release 4) :-)
It's like an iPhone with words on the screen, that's what. Stupid words. Shut up.
--Steve
Please stop stalking me, bro.
So... someone dumps a high yield nuke (more likely a few high yield nukes) on one location and the whole GPS system goes to hell after a few days/weeks? Please tell me this isn't the case. Otherwise someone didn't think their cunning plan all the way through.
We use GPS units to geocache, and accuracy has strangely seemed to have improved over the Summer. For those unfamiliar with GPS receiver tech, the newly available units use fast, parallel processing to greatly improve real-time sat processing. The new receiver chipsets have been problematic to use because they couldn't seem to get enough info and used echoed signals often in effort to increase accuracy. Maybe this update will put more downward bandwidth out there to help the new GPS receivers meet their potential.
Moderation in All Things... Especially Moderation - gurutc
http://www.mhall119.com
the current system is 70's era. It still uses 9-tracks, DASD units, and something called jovial that no one but old engineers with pants up to their chests have even heard of. The parts are freakish in their weight, their mechanical ways, and how unobtainable and unsupportable most everything about the old system is in 2007.
.... "click to read more"... but i wish for lots of shit... it doesn't make me sad.
The new system is modern. You can buy the machines from Sun today online. The OS is still updated and supported. The parts are commonplace like SATA drives, USB DVD drives, Sun workstations, etc. Unix may not be some newfangled operating system, but i can line up 1000 unix-savvy 30 year old-ish engineers and sysadmins for every one 60 year old-ish engineer that understands how to work with the IBM mainframes and jovial.
The savings comes only to US taxpayers - because its going to be way easier to for "us" (US citizens) to pay for younger engineers that are not all about to retire and younger hardware and software that shouldn't have been retired 20 years ago. "We" (US citizens) can pay less to keep GPS going now. The rest of the world.. well, i can't help you with costs since you've never paid for this thing. I'd just say "thanks" and leave it at that.
the iPod shuffle reference is to the fact that all the shuffle does is get music uploaded into it and play it back... it does *nothing* else. Okay... with that example in your mind... that's the same basic thing that GPS satellites do... "we" (US citizens) upload them with what to playback, and they play it back - and they have a clock to make sure they play it back at the right speed.... they practically do nothing more than that.
yeah, my headline was shortend to save room, but in the end, i had to end-up retyping it here. I wish they would have simply said
guns kill people like spoons make Rosie O'Donnell fat.
it's a joke about Steve Jobs. Laugh, bitches.
Please stop stalking me, bro.
If the legacy crap works, it isn't crap.
Truer words were never spoken.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
After reading the iPod bit, I had to doublecheck to make sure the submission wasn't from you-know-how, but then I realized it both made too much sense and contained too little gobbledygook to be from him.
However, now I'm going to be anxiously watching the firehose for an article announcing Apple's new iDecay line of atomic clocks. These will be far better than the Air Force's because they'll have built in battery packs instead of relying on solar power, and offer touch sensitive screens which will redefine the paradigm of atomic clock interfaces.
I crashed a descendant of a PDP-11 numerous times. And not on purpose. It was an application that may not particularly have been well-written. Butt It would generally crash at least twice weekly and you just hoped you had saved recently.
It was an RT-11 running the CMX 3600 software.
No BSOD but that's because it was not capable of generating a blue screen. It was green or amber. Take your pick.
Gods don't kill people, people with gods kill people.
This is by no means a "keep the legacy crap" rant -- systems you can't buy parts for without an unlimited budget should be retired ASAP.
However, I wonder who's handling the conversion for them, or if the Air Force is doing it themselves. I've seen great legacy conversion projects, and been involved in some really awful ones. One problem is just a lack of people who know enough about the "old" system to implement the software in the "new" side. The other, and far worse one is when companies (not militaries, mind you) bring in contractors who know _nothing_ about the hidden surprises in the old system, or nothing about the actual real-world application the computer is supporting.
As long as the system's not running J2EE or outsourced to a bunch of "expert" consultants, I'm guessing we're fine. But there is one key thing that's lost on "modern" IT -- proven systems work. Just because something is new doesn't mean it will work better! This is why I'm glad they stuck with UNIX instead of Linux or Windows.
Side note, how much do you think IBM was charging to maintain that monster??
It's more than just the mainframe ... in fact, that was probably the cheap part. The expensive part was developing software that:
A lot was on the line with this -- the Air Force has bombs and cargo pallets that rely on GPS for precision drops. The Army has a GPS-aided artillery system now. The financial sector uses the GPS timing signal for transaction management. A lot of the $800 million was no doubt an investment in testing the system so that, when it finally came online, the poop wouldn't hit the proverbial fan.
!#@%*)anks for hanging up the phone, dear.
Great, they spent a ton of money so that -- what, GPS will *work*? It already did!
Upgrading from 1970s technology to Unix? Unix *is* from the 1970s! The whole reason most slashdotters think it's the whole world is because they grew up with it -- i.e. it's "always" been here. OK it's been updated a lot since the old days but so have IBM mainframes. DASDs are SCSI disks these days.
Sorry to rant, I'm just so sick of companies/governments pouring resources into replacing working systems just because the current crop of wet-behind-the-ears CS grads have been trained to snicker at the stuff that has been making everything work like clockwork all these years.
I trust the administrators of the system will make sure the code is robust against the epoch rollover.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
The previous system, installed at the Satellite Control Facility, or "Blue Cube" (Onizuka AFB) in Sunnyvale, was physically huge. It was the Technology that Put Men On the Moon: Philco consoles, just like in Apollo Control.
Each time a satellite needed a trajectory adjustment, it took three computers and lots of people. The signal processing was done in something called an Emulated Buffer Controller, which was a transistorized device emulating a previous tube device. The real-time processing was done on one of several UNIVAC 490 series machines from the 1960s, and the trajectory computation was done on a CDC 3800 mainframe from the 1960s.
All this gear was interconnected through big manual patchboards, where, for each satellite pass, people plugged in cables to pass data from the ground station links to the buffer controller to the UNIVAC machine to the CDC machine to the console system.
This operation just drove the satellites, not the payload. The USAF, in a very Air Force way, makes a strong distinction between "driving the bus" and operating the payload. Anything that involved commanding the satellite to move or change orientation went through the Satellite Control Facility. Payloads (GPS, cameras, receivers, etc.) were controlled by the using agencies elsewhere, over separate data links.
The SCF's ground stations had (and still have) large (20 meter) steerable dishes that can communicate with their satellites over a low-bandwidth link regardless of the satellite's orientation, even if it's tumbling. There are about eight ground stations, spaced around the world, and they can track as well as communicate. Once the satellite is properly stabilized and oriented, the wide bandwidth directional links used by the payload come up. Those use smaller ground antennas, so as not to tie up the big tracking dishes.
This was finally phased out in the late 1980s, when control moved to Falcon AFB. Still, during the entire history of the Satellite Control Facility at the Blue Cube, no satellite was ever lost due to an operational error there. That's partly why upgrades were delayed.
The upgrades generally maintained the structure of the system, without doing a complete redesign. (A complete redesign was tried once, in the early 1980s. It flopped.)
And you're typing on a computer that was manufactured by your buddies in the "Resistance" in Iraq made out of rocks, dirt and camel shit, right?
My BFF Jill owns one of those. I don't. TISNF.
You can hold down the "B" button for continuous firing.
And it better stay that way.
I don't want a tomahawk crashing into my house accidentally because of some ipod/windows update or ACPI issue in the intel firmware, or since a core had to goto a wait state for some multitasking thing. Sometimes too many features bury the original intent.
Technology isn't a hammer looking for any nail.