>The easiest roll stability using gyroscopes may well be to use
>"rollerons". These are flaps outboard on the fins of the rocket, each
>with a spinning disk that hangs out into the airstream to drive its
>rotation. If the rocket rolls, the precession on the spinning disk
>drives the flap out into the airstream with a force proportional to
>the rotation rate. As the rocket corrects, the flaps move back into
>This scheme was used in early air-to-air ordnance, most notably the
>AIM 9: the electronics weren't fast enough to guide in pitch, roll and
>yaw, so the design engineers replaced electronic roll control with a
>purely mechanical system.
>On Mon, 15 May 2000 02:48:58 GMT, "Chris Taylor Jr."
>>I need help on making a gyro stabilized rocket
>>Not interested in totally stable, Just Roll Stability
>>I will assume I can design it to be Fin stable to counter the Precession
>>that will result from just one gyro.
>>I assume I just mount it so the gyro's spin plan is parallel with the length
>>of the rocket ?? (side ways ??)
>>Any Ideas ??
>>This post was spell checked please forward all spelling complaints to
>>Trust me you can Mail me without Mods
To further describe them (I used to load these things in the Air Force), the
rollerons are notched, like a thick (.25" or so) table saw blade.
Keep in mind that the rollerons need to be spun up prior to launch (on
Sidewinders, the airflow over them while in flight spun them up) and need to be
on really good bearings. There is an article in an old HPR magazine where
someone used this method to provide roll stability. They had air nozzles that
went up into the trailing edge of the "flap" containing the rolleron. This had
the dual purpose of getting them spinning and holding the flap at a neutral
position at launch. The flap also needed to be damped so that it wouldn't move
too far one way or the other.
Hope this helps a bit more.
John O'Donnell NAR 60742 L2 CSAR Sec #113