Slashdot Mirror


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."

18 of 170 comments (clear)

  1. Yay! by Anonymous Coward · · Score: 5, Funny

    They finally upgraded from 1970s technology to..

    ..Unix. Oh.

    Um.

    Yay!!!

  2. wow. by White+Shade · · Score: 5, Insightful

    "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!
    1. Re:wow. by blhack · · Score: 4, Insightful

      Actually the ipod shuffle thing confused me. Are they talking about the size of the device? Are saying that the device is meant to play music? Do they mean that it is simply powered by a battery? Seriously, I am completely failing to see any correlation between a military satelite and a white ego inflating piece of plastic that was built by the lowest bidder in some third world country.

      I propose a new godwin-esque law. First person to mention an apple product in a story that has absolutely NOTHING to do with apple gets 30 lashings.

      --
      NewslilySocial News. No lolcats allowed.
  3. Re:Confusion by eln · · Score: 5, Funny

    I'm not confused, I'm pissed! The Air Force apparently had solar powered iPod shuffles way back in the 1970s while the rest of us had to wait until 2005, and ours aren't even solar powered!

  4. what your post is like by thegnu · · Score: 4, Funny

    It's like an iPhone with words on the screen, that's what. Stupid words. Shut up.
    --Steve

    --
    Please stop stalking me, bro.
  5. Re:Big Iron by Detritus · · Score: 4, Insightful
    If the legacy crap works, it isn't crap. I never had a PDP-11 "blue screen" on me.

    Real programmers use FORTRAN, not the quiche-eating boutique language-of-the-month.

    --
    Mea navis aericumbens anguillis abundat
  6. i was edited and my points were lost.... by gsfprez · · Score: 5, Informative

    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.

    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 .... "click to read more"... but i wish for lots of shit... it doesn't make me sad.

    --
    guns kill people like spoons make Rosie O'Donnell fat.
    1. Re:i was edited and my points were lost.... by Santheman · · Score: 4, Interesting

      I was at "Schriever" (Falcon back then) from 1992 to 1994 and the GPS DASDs were being replaced. I know, as I was in the GPS module on a daily basis and the new drive enclosures were microscopic compared to the DASDs. Not sure where the GPS DASD references are coming from. The GPS module was the first to replace the DASDs as they had all the money. San

  7. Re:Maybe My Imagination by gsfprez · · Score: 5, Informative

    That accuracy seemed to have improved a number of individual times during the winter and summer is completely consistent with the way the transition practice runs and actual transition event took place.

    Increased bandwidth: No, absoultely not in any way. Nothing is different parameter-wise with this transition from the user perspective. In fact, that was one of the hardest parts of the transition - to make the new system interact with the user segment (thru the Space segment.. aka: the satellites) in the exact same way as the old system.

    I apologize for not being more specific than that... i also stated in my submission that i am extremely hesitant to say anything unless i'm 100% sure that its public knowledge.

    So, if you think i'm beating around the bush, you're right. I'm not doing it for effect.. i'm doing it to keep my job and because security is paramount.. not just for US folks, but for everyone that uses GPS.. and i hear a few people are getting into it these days... kinda like CB radios and that Internet thing.

    --
    guns kill people like spoons make Rosie O'Donnell fat.
  8. Re:Big Iron by timeOday · · Score: 4, Insightful

    Is it still called a budget when you get however much money you ask for?

  9. Re:Confusion by megaditto · · Score: 5, Funny

    It's the Air Force that should be pissed. They have paid a billion for the first 27 iPods, while those that waited bought theirs for $300... AF should demand a store credit!

    --
    Obama likes poor people so much, he wants to make more of them.
  10. Hope the reliability is just as good! by ErichTheRed · · Score: 4, Interesting

    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??

  11. Re:It takes $800 million to replace a mainframe? by PhxBlue · · Score: 4, Insightful

    It's more than just the mainframe ... in fact, that was probably the cheap part. The expensive part was developing software that:

    • Can communicate with each of the satellites currently on-orbit. We have GPS Block II, II-A, II-R, II-R(M), and (soon) II-F satellites in orbit, and each block speaks a slightly different language.
    • Transmits the same timing and navigation data that the satellites are used to getting from the old system. I don't know much about the technical aspects of that, but I know it's not easy.
    • Is easier to maintain. I don't know what language the new system was written in, but I imagine it's easier to support than code that was written 22 years ago.
    • Works without people noticing. This is the toughest part, and it's why the Space and Missile Systems Center commander said that this is like swapping out an engine while the car's driving down the highway at 65 mph. Think about how often in the past 15 years or so you've had to worry about whether or not you would have GPS.

    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.
  12. Re:Confusion by langelgjm · · Score: 5, Funny

    Q: What are they going to do with a billion dollar credit at the iTunes store? They song catalog isn't nearly that big!

    A: Ringtones.

    --
    "Anyone who [rips a CD] is probably engaging in copyright infringement." - David O. Carson
  13. You should have seen the old system by Animats · · Score: 5, Informative

    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.)

  14. Re:Confusion by Amouth · · Score: 4, Funny

    so they will buy A sweet desktop - and maybe have enough left over for a monitor, or a two button mouse

    --
    '...if only "Jumping to a Conclusion" was an event in the Olympics.'
  15. Re:Confusion by WhatAmIDoingHere · · Score: 4, Funny

    You could almost afford a sweet Mac Pro with that rebate, I guess.

    --
    Not a Twitter sockpuppet... but I wish I was.
  16. Re:Big Iron by ChrisA90278 · · Score: 4, Insightful

    "If the legacy crap works, it isn't crap"

    I said that once too. But then we worked out the cost of maintainance and electrical power, in other words the montly cost to run and found a new system would pay it's own cost in under a year.

    Even at home I've unplugged systems simply due to the $0.24 per kilowatt hour cost to power them. (Using an old Pentium III running UNIX as a wifi router and firewall works well but sucks electrical power big time.) I actually saved money by replacing a working system. GPS did the same thing but on t much larger scale.