Rocket Flight Computer Readout

8 responses to “Rocket Flight Computer Readout”

1. 

   jitze

   Nov 10, 2009 at 9:36 pm

   What was going on at 19 seconds? Not only did barometric altitude blip positive for a moment, but G forces took a wild swing both pos and neg. Was this the drogue/parachute deployment? If so – it looks like the parachute was connected to the fuselage with the mother of all bungee cords…

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2. 

   jurvetson

   Nov 10, 2009 at 9:53 pm

   Yes! The red spike is the upward yank on the airframe of the parachute unfurling and finally filling with air… almost 6 seconds later. It was a brand new chute and I had not aired it out in advance, so it was still tightly packed.

   It can be a bit harsh up there. So I loop the kevlar shock cord and use painter’s tape to soften it’s unraveling. I also added a tennis ball in line for contact with the rim of the airframe (to prevent zippering if deployed at speed).

   I added some mouse-over notes on the graph.

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3. 

   photon~wave

   Nov 10, 2009 at 10:08 pm

   Velocity curve looks strange: speed goes to zero
   4 seconds before apogee and the curve disappears(!?).

   Motor data can be read at thrustcurve and here.

   What kind of nozzle was used in this flight?
   Could you write the total rocket mass at launch pad?

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4. 

   menlo

   Nov 11, 2009 at 2:20 am

   Reminds one of that chart Obama’s economists put out to sell the stimulus. Unemployment is the rocket shooting well past the predicted bending of the curve.

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5. 

   photon~wave

   Nov 11, 2009 at 1:35 pm

   How was the apogee (therefore chute ejection) determined?
   Usually it’s done from the zero-crossing in velocity, but looking
   at the figure, it seems like barometric sensing was used.
   By the way, your tidbits in the mouse-over notes are really interesting.

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6. 

   sbove

   Nov 11, 2009 at 8:30 pm

   Would 30Gs kill a mouse-astronaut? Could you rig an ekg on one? 😉

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7. 

   photon~wave

   Nov 11, 2009 at 9:56 pm

   @sbove: Before John Stapp experiments in 1947,
   the aerospace conventional wisdom was a man
   would suffer fatally around 18G.
   Stapp was subjected (voluntarily) to 46.2G !
   But the stress is not recommended 😉

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8. 

   Mentifex

   Nov 11, 2009 at 10:38 pm

   The "Notes" feature as used above is really neat. I wish I could learn to install such Notes inside an image of an AI MindGrid, so that Netizens could just wander around on the topology of the AI Mind and see explanations of central features pop up. But as an independent scholar in AI, I am much too busy learning 32/64-bit iForth for transferring my previous AI creations onto 64-bit Linux AI supercomputers As they said in ancient Greece, "he pumate men eos tas pollas ephthasen ascholias," which means, "The last dawn (of your life) comes before many of your desired accomplishments." Sigh.

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