Which cubesat project ?
On Sun, Sep 22, 2013 at 5:49 PM, Daniel Schultz <[email protected]> wrote: > >I just want to ask a question: If you have a motor of a few hundred > >Newtons, how to you keep the attitude stable during the burn? For that > >matter, how do you get the attitude correct for the start of the burn? > > Simple question, simple answer: You use the magnetotorquers to point the > spin > axis in the right direction, check and check again to make sure you got > that > right, then use the magnetotorquers again to spin up the satellite at a > high > angular rate (maybe 20 RPM). The angular momentum of the spinning satellite > keeps it stable while the motor is firing. The motor thrust must of course > be > well aligned with the spin axis, but if the thrust vector is not perfect, > the > spinning satellite tends to even out the small deviation. > > One of the recent Cubesats carried high power model rocket engines to try > an > experimental orbit adjustment. They forgot to spin the satellite and the > Cubesat tumbled wildly as a result of the motor burn. Some of these groups > are > really lacking in basic physics knowledge (and we are not talking about wet > behind the ears students in that case.) > > Dan Schultz N8FGV > > > _______________________________________________ > Sent via [email protected]. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
