starship-design: Sail wrinkle

[TLG.van.der.Linden@tip.nl (Timothy van der Linden)]

Kevin,

>> This would work, but with the sail diameters I've seen, the centripetal
>> acceleration required to keep the sail relatively flat (thought it would
>> still present a convex face to the transmitter) will tear the sail apart.
>
>Huh?  in zero gravity, even the slightest rotation will open up the sail.
>and since the acceleration imposed by the beam will be evenly distributed,
>the sail should not have to spin very fast.

If it was a sail without a ship attached, then yes, it would stay flat
(assuming the beam density was the same everywhere).

But the tethers that go from the ship to the sail are not perpendicular to
the sail (unless you make it parabolic) and thus will excert a force on the
sail that is pointed to its center.


My last suggestion to get rid of uneven force distribution in the sail:
We could localy change the sail angle (by changing the length of a few
tethers) to compensate force that wants to wrinkle the sail.

Timothy