James Heath
Aerospace Meng
Supervisor: Dr K Smith
Venutian Exploration Project
[email protected]
Transfer
Purpose of Project
Diagram of transfer
(IPT) Hohmann Transfer
Venus
Earth
r2
ΔV1
ΔV2
Sun
Planet or body
concerned
This project concentrates on the transfer of a spacecraft from
Earth orbit to Venus orbit. Limitations of distance between earth
and Venus and positioning of the probe so that it can transmit data
back to Earth whilst in Venus’ atmosphere, give very specific mission requirements for the transfer and deployment of the probe.
The distance between earth
and Venus must be less than
100,000km on arrival and during data transmission.
The probe must be on the side
of Venus visible from earth during data transmission. There are
two solutions available shown
in case 1 and case2.
r1
Hyperbola Conic Section
Limitations
Earth *
Initial spacecraft orbit
Vearth
ΔV1
y
r
o
t
c
e
j
a
r
T
nus
Hyperbolic conic sections are used to calculate the velocity eccentricity and trajectory of an entry or exit of
an S.O.I (Sphere of Influence)
e
V
—
h
t
r
Ea
Escape Velocity: V∞
Venus +
n
o
i
s
s
i
h
t
m
r
s
a
n
e
ra
o
T
t
a
e
t
b
a
o
D
r
p
Sun
m
o
fr
Balloon orbit
Satellite Orbit
Venus S.O.I
Earth S.O.I
Simulation and Coding
#
The calculations for patched
conics will be coded into
matlab, some key equations
and variables are shown on
the right. Vector values will be
input into the code which will
produce values and plot corresponding Pork Chop Plots.
Using the most favourable values the transfer will then be
modelled in STK to simulate a
successful mission.
ΔV2
Equations:
Given that:
Planet
And vice versa for a capture
Vvenus
Probe & Deployment
The balloon probe will travel
around Venus using the
strong winds to move it. It
will collect atmospheric data
and transmit it back to earth
whilst it is still on the visible
section of Venus from Earth.
Separation of probe
from spacecraft
Deployment of
The balloon floats at a
balloon from parachute
varying altitude in Venus’ atmosphere and moves with
the strong winds
Launch Dates
Pork Chop Plot
Using patch conics, launch dates can be
calculated and pork chop plots can be
designed, to find the best design for the
transfer. Pork Chop Plots can be used to
compare many key fields against each
other to find the most desirable transfer
design.
http://www.cdeagle.com/interplanetary/porkchop.pdf
This is Pork Chop Plot
compares C3L
(Spacecraft energy level) against TOF (Time
of flight). This allows
the user to find the
best launch dates for
maximum efficiency
and also shortest TOF.