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Joris _

FASTSAT performing well; launch of small satellite coming next week | al.com - 0 views

blog.al.com/...at_performing_well_launch.html

MAD Space debris

shared by Joris _ on 29 Nov 10 - No Cached
  • Being able to launch a satellite from a satellite has numerous potential benefits to the military and scientists, but those benefits depend on the smaller satellite not hitting the mother ship when it launches and going where it needs to go.If the sail can deploy as planned to its 100-square-foot size - about as big as a six-person camping tent - and can guide the smaller satellite to its planned re-entry, it would also illustrate a new way to bring satellites back to Earth and reduce orbiting space junk.
Joris _

Japan probe overshoots Venus, heads toward sun - 0 views

www.washingtonpost.com/...AR2010120701077.html

MAD venus robust

shared by Joris _ on 08 Dec 10 - No Cached
sreejanag liked it
  • A Japanese probe to Venus failed to reach orbit Wednesday and was captured by the sun's gravitational pull
  • Akatsuki's engines did not fire long enough to attain the proper orbiting position
  • may be able to try again when it passes by Venus six years from now.
  • Joris _ on 08 Dec 10
     
    The usefulness of having a robust trajectory :) ... They have to wait 6 more years for another date with Venus ...
  • ...2 more comments...
  • Joris _ on 09 Dec 10
  • LeopoldS on 11 Dec 10
     
    I agree in general but just out of the stomach: is there really an optimised trajectory that would be able to avoid this kind of scenarios when main thrusters don't perform properly? Wouldn't you in any case end up in a sun-orbiting trajectory and have to come back after years??
  • Joris _ on 11 Dec 10
     
    "optimised trajectory" of course not, robust definitely! It was the subject of my paper presented at the AAS (the one in San Diego) "Designing robust interplanetary trajectories subject to one temporary engine failure". The problem here is that they do not have enough fuel for a correction maneuver that would allow to come back to Venus earlier, and break for a VOI. A robust scenario could have alloted the best amount of fuel and time to be able to recover from almost all possible unplanned events. In the paper, I introduce some confidence regions such that I get the robust control for p% chance of mission success in case m% chance of problem with the propulsion system.
  • Dario Izzo on 12 Dec 10
     
    You should run your method on this scenario and see if you could get a trajectory with a shorter come back time using the same spacecraft.... would be a big selling point for a new trajectory design approach
Joris _

The Pioneer Anomaly, a 30-Year-Old Cosmic Mystery, May Be Resolved At Last | Popular Sc... - 0 views

www.popsci.com/pioneeranomaly

MAD phy pioneer

shared by Joris _ on 16 Dec 10 - No Cached
LeopoldS liked it
  • Joris _ on 16 Dec 10
     
    "After decades spent thinking, arguing, hoping, and in the words of Turyshev, "making a career off of it," these scientists' interest in the Pioneer anomaly has, understandably, accumulated psychological baggage; in the case of many of them, a cloud of emotional investment has formed around the core of objective scientific inquiry. And clouds obscure things."
  • Joris _ on 16 Dec 10
     
    165 pages about it!! http://arxiv.org/abs/1001.3686
  • LeopoldS on 20 Dec 10
     
    good old Turyshev ...
Joris _

YouTube - Ascent - Commemorating Shuttle - 2 views

www.youtube.com/watch

MAD Space shuttle

shared by Joris _ on 13 Dec 10 - No Cached
LeopoldS and Joris _ liked it
  • Joris _ on 13 Dec 10
     
    An amazing compilation of slow motion videos of the space shuttle. Superb!
Dario Izzo

Probabilistic Logic Allows Computer Chip to Run Faster - 3 views

www.azonano.com/news.asp

INF MAD probabilistic computing AI

shared by Dario Izzo on 07 Dec 09 - Cached
  • Dario Izzo on 07 Dec 09
     
    Francesco pointed out this research one year ago, we dropped it as noone was really considering it ... but in space a low CPU power consumption is crucial!! Maybe we should look back into this?
  • ...6 more comments...
  • Ma Ru on 07 Dec 09
     
    Q1: For the time being, for what purposes computers are mainly used on-board?
  • Dario Izzo on 07 Dec 09
     
    for navigation, control, data handling and so on .... why?
  • Ma Ru on 07 Dec 09
     
    Well, because the point is to identify an application in which such computers would do the job... That could be either an existing application which can be done sufficiently well by such computers or a completely new application which is not already there for instance because of some power consumption constraints... Q2 would be then: for which of these purposes strict determinism of the results is not crucial? As the answer to this may not be obvious, a potential study could address this very issue. For instance one can consider on-board navigation systems with limited accuracy... I may be talking bullshit now, but perhaps in some applications it doesn't matter whether a satellite flies on the exact route but +/-10km to the left/right? ...and so on for the other systems. Another thing is understanding what exactly this probabilistic computing is, and what can be achieved using it (like the result is probabilistic but falls within a defined range of precision), etc. Did they build a complete chip or at least a sub-circiut, or still only logic gates...
  • Dario Izzo on 07 Dec 09
     
    Satellites use old CPUs also because with the trend of going for higher power modern CPUs are not very convenient from a system design point of view (TBC)... as a consequence the constraints put on on-board algorithms can be demanding. I agree with you that double precision might just not be necessary for a number of applications (navigation also), but I guess we are not talking about 10km as an absolute value, rather to a relative error that can be tolerated at level of (say) 10^-6. All in all you are right a first study should assess what application this would be useful at all.. and at what precision / power levels
  • Joris _ on 07 Dec 09
     
    The interest of this can be a high fault tolerance for some math operations, ... which would have for effect to simplify the job of coders! I don't think this is a good idea regarding power consumption for CPU (strictly speaking). The reason we use old chip is just a matter of qualification for space, not power. For instance a LEON Sparc (e.g. use on some platform for ESA) consumes something like 5mW/MHz so it is definitely not were an engineer will look for some power saving considering a usual 10-15kW spacecraft
  • Dario Izzo on 07 Dec 09
     
    What about speed then? Seven time faster could allow some real time navigation at higher speed (e.g. velocity of a terminal guidance for an asteroid impactor is limited to 10 km/s ... would a higher velocity be possible with faster processors?) Another issue is the radiation tolerance of the technology ... if the PCMOS are more tolerant to radiation they could get more easily space qualified.....
  • Joris _ on 08 Dec 09
     
    I don't remember what is the speed factor, but I guess this might do it! Although, I remember when using an IMU that you cannot have the data above a given rate (e.g. 20Hz even though the ADC samples the sensor at a little faster rate), so somehow it is not just the CPU that must be re-thought. When I say qualification I also imply the "hardened" phase.
  • Francesco Biscani on 08 Dec 09
     
    I don't know if the (promised) one-order-of-magnitude improvements in power efficiency and performance are enough to justify looking into this. For once, it is not clear to me what embracing this technology would mean from an engineering point of view: does this technology need an entirely new software/hardware stack? If that were the case, in my opinion any potential benefit would be nullified. Also, is it realistic to build an entire self-sufficient chip on this technology? While the precision of floating point computations may be degraded and still be useful, how does all this play with integer arithmetic? Keep in mind that, e.g., in the Linux kernel code floating-point calculations are not even allowed/available... It is probably possible to integrate an "accelerated" low-accuracy floating-point unit together with a traditional CPU, but then again you have more implementation overhead creeping in. Finally, recent processors by Intel (e.g., the Atom) and especially ARM boast really low power-consumption levels, at the same time offering performance-boosting features such as multi-core and vectorization capabilities. Don't such efforts have more potential, if anything because of economical/industrial inertia?
Joris _

Galileo space navigation system to be ready in 2014 | Business | Deutsche Welle | 07.01... - 1 views

www.dw-world.de/...0,,5096845,00.html

MAD GPS

shared by Joris _ on 07 Jan 10 - Cached
  • Joris _ on 07 Jan 10
     
    6 years later ...
  • Nicholas Lan on 08 Jan 10
     
    seems optimistic
Joris _

In Pictures: 10 Of Science's Biggest And Costliest Experiments - 2 views

www.forbes.com/...throughs-experiment_slide.html

space cost MAD

shared by Joris _ on 06 Dec 09 - No Cached
  • Joris _ on 06 Dec 09
     
    Half of them are space related!
Joris _

DoD Buzz | Back Away from GPS: AF Chief - 4 views

www.dodbuzz.com/...back-away-from-gps-af-chief

MAD GPS security

shared by Joris _ on 21 Jan 10 - Cached
  • develop alternatives to GPS
  • The fact that the U.S., which invented GPS and most of what depends on it (ATMs, gas pumps, trucking companies and lost spouses), would consider stepping away from the system marks a cultural and technological milestone
  • recommended that the U.S. scrap building five more GPS satellites and engage European allies on sharing their proposed Galileo global navigation satellite system
Joris _

planetarydefense.blogspot.com: Documents: Human NEO Mission Design Studies - 0 views

planetarydefense.blogspot.com/...cuments-human-neo-mission.html

MAD NEO Human_Exploration

shared by Joris _ on 11 Jan 10 - Cached
  • Joris _ on 11 Jan 10
     
    An interesting compilation of Human NEO mission concepts
Joris _

NASA Announces Designs for Personal Flying Suit - In Transit Blog - NYTimes.com - 1 views

intransit.blogs.nytimes.com/...signs-for-personal-flying-suit

MAD planes

shared by Joris _ on 22 Jan 10 - Cached
LeopoldS liked it
  • Joris _ on 22 Jan 10
     
    Awesome!! Basically a personal V-22 Osprey.
Joris _

NASA Budget Request for FY11 - 2 views

www.nasa.gov/...Budget_Overview_1_Feb_2010.pdf

MAD Earth Science propulsion

shared by Joris _ on 04 Feb 10 - No Cached
  • Joris _ on 04 Feb 10
     
    Very interesting ... particularly slides 13 to 15 if you read between lines.
Joris _

Panel Picks 3 Finalists for ESAs Cosmic Vision M class Missions | SpaceNews.com - 3 views

spacenews.com/...ic-vision-mclass-missions.html

MAD Class_M Science Marco Polo

shared by Joris _ on 20 Jan 10 - Cached
pacome delva liked it
  • “superb from a science standpoint,” but beyond Europe’s current budget
  • There was some questioning of the cost estimate for Euclid, but at some point you have to decide: Either you don’t believe the estimates that [ESA science program managers] produced, or you assume their estimates are credible. Euclid was the one mission where costs were debated, but the consensus was to use the cost estimates presented to us.
  • pacome delva on 20 Jan 10
     
    finally cross-scale is not selected, it was the only cosmic vision mission with multi-satellites formation flying, since the concept for Xeus has changed. There is still Swarm but it's not really formation flying... So ESA is missing something here...
Joris _

SPACE.com -- NASA to Boost Speed of Deep Space Communications - 1 views

www.space.com/...tion-network-speed-100122.html

MAD technology communications DSN

shared by Joris _ on 25 Jan 10 - Cached
  • a few megabits per second might someday get as much as 600 megabits per second, if not more. That could enable far more scientific payoff per mission in the long run.
  • new communication innovations such as disruption tolerant networking
  • one of the biggest communication revolutions will come from laser-driven optical communication
    • Joris _
      Joris _ on 25 Jan 10
       
      they kind-of stole my idea ;)
Joris _

NASA will miss Congressional deadline for asteroid tracking - Science Fair - USATODAY.com - 0 views

blogs.usatoday.com/...ine-for-asteroid-tracking.html

MAD NEO

shared by Joris _ on 25 Jan 10 - Cached
  • he panel finds the 2005 order to find 90% of Earth-threatening asteroids 460 feet or larger infeasible,
  • No method for diverting asteroids has been experimentally demonstrated
  • Options include a "gravity tractor" orbiting slow-moving objects and tugging them off course with tidal tugs, a "kinetic" impact of a heavy spacecraft into an asteroid, or a nuclear explosion
  • ...1 more annotation...
  • Unlike the dinosaurs, we are smart enough to do the math and figure out the answer that modest resources should be dedicated to the problem
    • Joris _
      Joris _ on 25 Jan 10
       
      "we are smart enough" is a completely subjective comment. Reading the article it does not give the same impression :|
Joris _

Robot mini space shuttle is go for April, says US air force * The Register - 2 views

www.theregister.co.uk/...x_37_go_for_april

MAD launcher space

shared by Joris _ on 15 Mar 10 - Cached
LeopoldS liked it
  • concept of operations development for reusable space vehicle technologies.
  • a robotic spaceplane able to remain in orbit for substantial periods before re-entering the atmosphere and coming in for a runway landing automatically
  • Joris _ on 15 Mar 10
     
    make you wonder when the FLPP will actually lead to something flying !
  • LeopoldS on 16 Mar 10
     
    I did not even know that the airforce continued the X37 project when it was cancelled at NASA ... interesting stuff indeed ...
Joris _

NASA could buy plasma engine for station reboost services - 1 views

www.flightglobal.com/...-station-reboost-services.html

nasa MAD low thrust

shared by Joris _ on 10 Mar 10 - Cached
  • enough to generate 1lb of thrust (0.00445kN) and fulfil the critical role of giving the Space Station a periodic altitude boost.
  • the most powerful electric engine in operation toda
  • , NASA is contracting Ad Astra Rocket for a lunar tug concept study, to take cargo from the Earth to the Moon and back, and deliver equipment in preparation for a human landing
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