Mass Driver CDR - Purdue University
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Mass Driver CDR March 10, 2020
Transcript of Mass Driver CDR - Purdue University
Mass Driver CDRMarch 10, 2020
Mission Profile (Mars → Phobos)
● Launch windows are defined by phobos
position and tether sling spin up time
○ Phobos must be -29.033° from
Olympus Mons (right ascension)
○ Max turnover = 3 launches/sol
● Acceleration Profile
○ 4.77 km/s Launch Velocity
○ 4.47 km/s Velocity past
atmosphere
○ 2 G’s net
● Total Orbital Flight Time 14.69 hrs
Orbital Trajectory
ΔV (km/s) Time (hrs)
Launch 4.77 6.17
Burn 1 0.286 8.52
Burn 2 0.375 RNDVZ
Total 0.661 14.69
Considerations & Deviations
● Acceleration modification
○ Make time and distance shorter
○ Launch Velocity includes drag and rotation
● Orbital analysis
○ No perturbations
○ No eccentricity/inclinations
● Risk Assessment
○ If launch fails, more ΔV is required
○ If burn 1 fails, the taxi will return to Olympus Mons
○ If burn 2 fails, no return possibility without significant ΔV
Mass Driver Objectives• Handle loads of our magnitude (passenger trains)
• Allows us to more easily decelerate the cradle for reusability
• Located at the base of Olympus Mons
• Using Null-Flux Coils for Repulsive Levitation
Mass Driver Objectives
• Updated battery sizing, spacing and model
• Two 1x1x1 m battery banks every 409 meters down the track
Mass Driver Overview
Important Parameters
• Track Length: 635 km (for taxi + cradle acceleration)
106 km (for cradle deceleration)
• Launch Duration: 4 minutes 14 seconds
• 2g constant acceleration
• Force required: 6.49 MN (propulsion)
1.11 MN (levitation)
• Propellant saved: 477 Mg
Maglev System Diagram
z
x
Image by Arch Pleumpanya
Coils: 1.6 million coils
on each side for
741 km trackSuperconducting
magnet
1.07 m
0.5 m
0.55 m0.55 m
0.31 m
HTS Magnets:
80 magnets total for
Flevitation= 1.11 MN
Mass Driver Launch Transition
Linear Induction Controller
Max
perturbation
Assumed
Voltage
Mass of Cart
and Taxi
Time before
Liftoff
Max Drag
5.3 kN 100 V 121 tons 254 sec 53 kN
Null Flux Controller
Frequency of AC current 1 kHz
Max amplitude of Current 5.24 * 1015 A
Taxi-Grabbing System
Image by Erick Smith
Taxi Grabbing System
Taxi Grabbing Info
Tether Length 700 kms
Track Diameter 1,394 kms (+- 2
kms)
Max Taxis Can
Catch
(simultaneously)
3 Taxis
Olympus Mons
Diameter
624 kms
Image by Erick Smith
Electromagnetic Cradle (EMC)
Cradle
Information
Propulsion Repulsive w/
Wheel Assist
Mass 80 tons
Material Aluminum 6061
T6
Length 25 meters
Height 8 meters
Width 30 meters
Image by Erick Smith
Mass Driver Materials
Mass Driver
Parts
Materials
Rail Rhenium beams
Magnets HTS Rebco
Magnet Coolant
(Cradle)
Liquid Helium
Magnet Coolant
(Rail)
Freon
Image by Natasha Yarlagadda
Power Consumption (Single Launch)
Mars The Moon
Peak Power
Consumption (GW)
43.1 19.5
Total Energy
Consumption (GJ)
5,220 1,240
● Power consumption peaks at the Taxis top
speed when drag force is at a maximum
● Power during launch is provided by Solar
and Batteries
● Magnetic Drag is neglected at both locations
● Air Drag is neglected on The Moon
Power Production and Storage (3 Launches)
Mars The Moon
Solar Panel Power (MW) 6.04 1.44
Solar Panel Area (km2) 0.339 0.0035
Battery Volume (m3) 3.1 * 103 738
Battery Mass (Mg) 6,690 1,590
Total Mass (Mg) 6,750 1,600
● Solar Panel Power is based off a
recharge time of one month total for the
three launches
● Solar Panels provide limited energy and
charge the batteries over the long
duration between sets of launches
● Batteries are capable of holding enough
energy to launch 3 Taxis consecutively
● Solar Area on the Moon is much less due
to the lack of Air Drag and increased
intensity of the Sun
Human Considerations
Forward Acceleration
Backwards Acceleration
7G’s absolute max acceleration (at any given time), 2G’s max sustained
acceleration recommended for normal civilian
Mass Driver Thermal Management
Thermal
Systems
(Mars)
Mass Volume Power
Heat Sinks 6.49 Mg 34,285.7
m3
Passive
Cooling
Liquid
Cooling for
the Rail
172.8 Mg 5.1 * 108
m3
230 MW
Cradle
System
12.5 Mg 100 m3 769.23 kW
1. M. Johnson, P. Cote, F. Campo and P. Vottis, "Railgun Erosion Simulator," 2005 IEEE Pulsed Power Conference,
Monterey, CA, 2005, pp. 245-248.
Dylan Pranger
Thermal Systems
Dylan Pranger
Va
cu
um
Ou
tsid
e
Vacuum
Con
de
nser
Magnet
Liquid Helium
