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  1. #326
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    Interesting article about the processors Perseverance uses: https://www.theverge.com/tldr/2021/3...-cpu-imac-1998

    Basically, it uses a special radiation-hardened variant of the same 200MHz PowerPC processor from the original iMac. Fancy new chips can't handle the radiation on Mars. The article doesn't mention it, but I'm guessing the power consumption might also be an issue.

  2. #327
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    Here’s a summary of things that have happened on earth when redundant processors aren’t put in:

    https://www.independent.co.uk/news/s...84616.html?amp
    _______________________________________________
    "Strapping myself to a sitski built with 30lb of metal and fibreglass then trying to water ski in it sounds like a stupid idea to me.

    I'll be there."
    ... Andy Campbell

  3. #328
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    Quote Originally Posted by Dantheman View Post
    Interesting article about the processors Perseverance uses: https://www.theverge.com/tldr/2021/3...-cpu-imac-1998

    Basically, it uses a special radiation-hardened variant of the same 200MHz PowerPC processor from the original iMac. Fancy new chips can't handle the radiation on Mars. The article doesn't mention it, but I'm guessing the power consumption might also be an issue.
    Maybe also the fact that it's powered by an RTG with 4kg of Pu238 onboard might justify the need for some radiation hardening. But yes, the space flight and thinner atmosphere of Mars also leave it open to solar radiation.
    Fat fuck bubbas are not erosion.

  4. #329
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    Quote Originally Posted by BC. View Post
    Thanks...unfortunately no sky crane on these......but when I show the NASA actual/CGI footage, kids are definitely thinking about how they could do it...

    I’ll see if I can post a video of some drops this week. I’m always surprised at the ones that work/protect the egg even without a parachute.....

    We do build/launch model rockets in June to close out their 3 years of science with me.....nice way to end their time with me.
    You are an awesome individual to inspire your students the way you do. My hat is off and I take a deep bow, sir.

    Quote Originally Posted by DJSapp View Post
    Maybe also the fact that it's powered by an RTG with 4kg of Pu238 onboard might justify the need for some radiation hardening. But yes, the space flight and thinner atmosphere of Mars also leave it open to solar radiation.
    What is Pu238, DJ? I'm assuming it's running a small reactor, but how? I can't imagine steam turbines making electricity.

  5. #330
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    Quote Originally Posted by splat View Post
    You are an awesome individual to inspire your students the way you do. My hat is off and I take a deep bow, sir.



    What is Pu238, DJ? I'm assuming it's running a small reactor, but how? I can't imagine steam turbines making electricity.
    https://en.wikipedia.org/wiki/Multi-...tric_generator
    Aim for the chopping block. If you aim for the wood, you will have nothing. Aim past the wood, aim through the wood.
    http://tim-kirchoff.pixels.com/

  6. #331
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    Quote Originally Posted by splat View Post
    What is Pu238, DJ? I'm assuming it's running a small reactor, but how? I can't imagine steam turbines making electricity.
    It is a RTG where heat from Plutonium's radioactive decay generates power via a thermocouple. No turbines, no control rods, really no moving parts, and passive cooling. Super reliable, long lasting, doesn't care about distance from the sun/darkness/dust storms like solar/battery systems... most outer solar system probes use RTGs.
    Quote Originally Posted by blurred
    skiing is hiking all day so that you can ski on shitty gear for 5 minutes.

  7. #332
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    New Mars Cameras

    Quote Originally Posted by splat View Post
    You are an awesome individual to inspire your students the way you do. My hat is off and I take a deep bow, sir.
    Thanks splat...appreciate it. It’s a fun project...that had some real life relevance this year with the Perseverance landing. Tried to get some video up of the drops today...but upload not cooperating.

    I have 10 more years of this gig....out of PA...and it’s off to the mountains for my “real” job....100+ day dirtbag/mag/ski tech/bum....

    Hope some of you will still be around so you can “show me the way”...lol.

    Sorry...back to Mars stoke!

  8. #333
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    Quote Originally Posted by From_the_NEK View Post
    Thanks, Dood! Thought it was plutonium but it's been a while since I've looked at the periodic table. Being a downwinder born in a plutonium cloud from Hanford, I should have looked into adapting and internalizing some of that solid state shit and gotten upgraded with a 120 volt plug a long time ago. Explains my penchant for shorts and tank tops all winter...

  9. #334
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    Quote Originally Posted by splat View Post
    Thanks, Dood! Thought it was plutonium but it's been a while since I've looked at the periodic table. Being a downwinder born in a plutonium cloud from Hanford, I should have looked into adapting and internalizing some of that solid state shit and gotten upgraded with a 120 volt plug a long time ago. Explains my penchant for shorts and tank tops all winter...
    Run a little hot ehh?

    You can see the power supply unit mounted to Perseverance in the panoramic:
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    Aim for the chopping block. If you aim for the wood, you will have nothing. Aim past the wood, aim through the wood.
    http://tim-kirchoff.pixels.com/

  10. #335
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    We built the LCAM for JPL and they used it for the images that did the terrain relative navigation (picking the landing spot) on the rover during EDL. They did not run the camera at max frame rate or pixel frame size, just used it for what they needed, but I still like the images. Purposely underexposed, but can stretch for a better looking image. Field of view is pretty awesome. They are all on the public raw images page under Lander Vision System Camera. https://mars.nasa.gov/mars2020/multimedia/raw-images/

    All the time I put in on MSL MARDI, this image reminded me of being the first to see the heat shield fall away on MSL:


    Shadow of rover before wheels dropped and dust kicking up:


    Watson cover open image is also posted (but not debayered ), so that was exciting to get this morning.

  11. #336
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    took these last night (camera on arm)and they just arrived...looking at belly of rover with heli still attached but debris shield deployed:
    Click image for larger version. 

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  12. #337
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    heli update...Lots of WATSON!

    NASA is targeting no earlier than April 8 for the Ingenuity Mars Helicopter to make the first attempt at powered, controlled flight of an aircraft on another planet. Before the 4-pound (1.8-kilogram) rotorcraft can attempt its first flight, however, both it and its team must meet a series of daunting milestones.

    [...]
    The helicopter deployment process will take about six sols (six days, four hours on Earth). On the first sol, the team on Earth will activate a bolt-breaking device, releasing a locking mechanism that helped hold the helicopter firmly against the rover’s belly during launch and Mars landing. The following sol, they will fire a cable-cutting pyrotechnic device, enabling the mechanized arm that holds Ingenuity to begin rotating the helicopter out of its horizontal position. This is also when the rotorcraft will extend two of its four landing legs.

    During the third sol of the deployment sequence, a small electric motor will finish rotating Ingenuity until it latches, bringing the helicopter completely vertical. During the fourth sol, the final two landing legs will snap into position. On each of those four sols, the Wide Angle Topographic Sensor for Operations and eNgineering (WATSON) imager will take confirmation shots of Ingenuity as it incrementally unfolds into its flight configuration. In its final position, the helicopter will hang suspended at about 5 inches (13 centimeters) over the Martian surface. At that point, only a single bolt and a couple dozen tiny electrical contacts will connect the helicopter to Perseverance. On the fifth sol of deployment, the team will use the final opportunity to utilize Perseverance as a power source and charge Ingenuity’s six battery cells.

  13. #338
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    Thanks for bringing the stoke, dude!

  14. #339
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    launch lock released:


    video made during atlo showing all the steps, 40 sec is the launch lock release:
    https://www.youtube.com/watch?v=d5ehz7pHprk

  15. #340
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    Rad
    This is a prelude to helisking CO2 pow on Olympus Mons
    Quote Originally Posted by blurred
    skiing is hiking all day so that you can ski on shitty gear for 5 minutes.

  16. #341
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    Quote Originally Posted by Summit View Post
    Rad
    This is a prelude to helisking CO2 pow on Olympus Mons
    Get Hacksaw on it.

  17. #342
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    So cool. I wonder what kind of mods they had to make to that helicopter to get it to work in Mars' thin atmosphere. Looks like it has really wide blades relative to earth bound heli-drones.
    Also, it is also interesting to think about how the legs of the heli drop into place. There must be some sort of assistance (e.g. springs) to make sure they go all the way down and snap into place. If the drop-and-snap is strictly gravity based, they would have to ensure the mechanism accounts for the weaker gravity on mars.

    Now I'm also thinking that the weaker gravity+the thin atmosphere may actually cancel out having to do a whole lot to make up for the reduction in lift due to the thin atmosphere.
    Aim for the chopping block. If you aim for the wood, you will have nothing. Aim past the wood, aim through the wood.
    http://tim-kirchoff.pixels.com/

  18. #343
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    Quote Originally Posted by From_the_NEK View Post
    So cool. I wonder what kind of mods they had to make to that helicopter to get it to work in Mars' thin atmosphere. Looks like it has really wide blades relative to earth bound heli-drones.
    Also, it is also interesting to think about how the legs of the heli drop into place. There must be some sort of assistance (e.g. springs) to make sure they go all the way down and snap into place. If the drop-and-snap is strictly gravity based, they would have to ensure the mechanism accounts for the weaker gravity on mars.

    Now I'm also thinking that the weaker gravity+the thin atmosphere may actually cancel out having to do a whole lot to make up for the reduction in lift due to the thin atmosphere.


    It was purpose-built for the Martian atmosphere.


    posted on the last page...


    Quote Originally Posted by Norseman View Post

    life ain't guaranteed, love your people while you can

  19. #344
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    lets not forget MSL, from last week:

  20. #345
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    Mars dust sastrugi!

  21. #346
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