Space Propulsion - IAP/TU Wien
Space Propulsion - IAP/TU Wien
Space Propulsion - IAP/TU Wien
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
<strong>Space</strong> <strong>Propulsion</strong><br />
Example 6: One-Axis Maneuver<br />
Find the minimum time required for a spacecraft to perform a 90-deg turn about the z axis<br />
with two thrusters if the spacecraft has the following characteristics:<br />
Mass of S/C = 500 kg,<br />
Radius of S/C = 0.75 m<br />
Moment of inertia about the z axis ≅(2/5)M S/C.<br />
L 2 = 112.5 kg.m 2<br />
Moment arm = 0.75 m<br />
Thrust of each engine = 10 N<br />
and<br />
Θ m<br />
= π/2 = 1.5708 rad<br />
t<br />
2. Θ<br />
I<br />
m v<br />
min<br />
= =<br />
=<br />
nFL<br />
2*1.5708*112.5<br />
2*10*0.75<br />
4.854<br />
s<br />
How much propellant was consumed by the maneuver if I sp<br />
= 1900 m/s ?<br />
nFt<br />
m 2 * 2 *10 * 4.854<br />
m<br />
p<br />
= 2 =<br />
= 0. 102<br />
I 1900<br />
sp<br />
kg