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Section III Presentations February 6, 2020
Eli SitchinFebruary 5, 2020
Discipline: CADVehicle and Systems Group: Cycler
2
The Problem: Determine the Configuration of the Cycler Vehicle
Requirements
• The cycler must accommodate three docked taxi vehicles without negatively affecting
stability.
• The cycler must rotate at a safe speed while providing > 0.38 g.
• All habitable portions of the cycler must be accessible from all other habitable portions.
Assumptions
• 65 m3 of habitable volume per person, with 70 total passengers
• 4 habitation modules
• 1 g at habitation module ceiling
Need to Determine
• Distance between the habitation module and axis of rotation
• Habitation module dimensions
• Taxi docking module placement
3
Preliminary Design
Considerations
• All structures currently modeled as
aluminum
• Mass to be estimated once
additional materials and
thicknesses are specified
Rotation Rate 0.1566 rad/s
Habitation Ceiling Radius 400 m
Floor Area1 2551 m2
Pressurized Volume1 17606 m3
Habitable Volume1 5451 m2
1 Habitation and Elevator-Habitation Interface only
Next Steps
• Determine solar panel requirements and
positioning
• Determine propulsion system positioning
• Create Habitation Module mockup
Habitation
Superstructure
SupportElevator
Elevator-
Habitation
Interface
4
Erick SmithFebruary 6th, 2020
CADLanding Pad(s)
Landing Pad Hub
Requirements:
• Must supply its own power
• Must be able to land three
taxis at a time
Solutions:
• Three landing pads
• Solar array ONLY for
landing pads and ATC
bunker
Landing Pad Itself
Requirements:
• Protects against the environment
• Move the rocket from vertical to
horizontal
• Load the taxi to the mass driver
system
• Refuel and resupply the taxi
Solutions:
• Underground gate
• Using a cradle help passengers
disembark and load taxi to mass
driver
Nicholas DeAngeloFebruary 6th, 2020
CommunicationsTaxi Vehicle (Phobos Tether and Mars Mass
Driver)
Problem
• Communication for Taxi Vehicle with Mars Mass Driver and Phobos
Tether - MPV• RF
• Ground satellites on Mars and Phobos
• Assumptions
• Allowed up to 1kW of power (allotted from Power and Thermal)• Laser Communication not effective through atmospheric barrier
• 9m satellites on Mars surface and Phobos surface• Same as Earth ground satellites
Taxi Vehicle Antenna
• Future Considerations:• Satellites in Mars orbit for continuous communication
• Account for further losses for more accurate/realistic data
• Minimize Mass, Power, Volume while staying within requrements
Parameter Value (unit)
Diameter 2 m
Mass [1] 20 kg
Power Needed 890.5 W
Frequency [3] 130 GHz
Adam WootenFebruary 6th, 2020
Communications Team LeadCycler – Laser/Optic
The Problem
Given Requirements
• Continuous Communication
• 1 Gbps HD Communication
Requirements Flowdown
• 4 dB Gain Margin
• Redundancy Cycler-Earth Comm
• Power < 25W
Goal
• Keep Same Antenna as SatellitesPhoto By: Adam Wooten
Max Cycler-Earth Distance: Jordan Mayer & Colin Miller
*Not To Scale*
Cycler Communication Optical Hardware
Mass (kg) 180
Power (W) 24
Volume (m3) 5.0
Antenna Diameter (m) 1.20
Gain Margin Min for
Relay (dB)
5.4903
Gain Margin Min for
Cycler-Earth (dB)
4.0860
Antenna Characteristics
Comm System Mass, Power, Volume
Photo By: Adam Wooten Photo By: Adam Wooten
*Not To Scale* *Not To Scale*
Cycler to Earth Max
DistanceCycler to Relay Max
Distance
Sidharth PrasadFebruary 6, 2020
Discipline: ControlsSystem: Taxi Vehicle
The Problem: Mars Entry
● Problem: Need to entry angle and necessary fuel to land
● Solution: Setup MATLAB file modelling dynamics
○ Too low angle exits atmosphere, too high can hurt
○ BC is an important parameter for determining good angles
● Going forward
○ Need more accurate taxi parameters, and can improve
atmospheric model and model accuracy
○ Need to calculate fuel needed to land and control for angle
○ Need to ensure that other metrics such as heat are not
surpassed
Graphs
BREAKResume at 2:10
Brady WalterFebruary 6, 2020
ControlsAnalysis of Communication Satellite Control
Problem
Requirements for Control
• Antenna pointing in correct direction
• Solar panels at optimal orientation
• Ion thruster oriented properly for course corrections
Considerations
• Continuous, accurate pointing required
• Gravitational and solar radiation apply torque
Solution
Reaction Wheels
• 3 wheels: pitch, yaw, roll
• Rockwell Collins RSI-12
Independent Solar Panel Control
• Panels rotate about one axis
• Maximize area in direct sunlight
Further Steps
• Develop feedback controller for solar panels to face sun
• Develop feedback controller for reaction wheels
Parameter (Per
Wheel)
Value
Mass 4.85 kg
Diameter .247 m
Height .085 m
Max Power
Consumption
191.25 W
Lifetime 15 yrs
Beverley K.W. YeoFebruary 6th, 2020
ControlsCycler – Stability Analysis
Problem: Spacecraft stability against perturbations
In space: no aerodynamic forces 🡪 stabilization via spin (gyroscopic effect)
What criterion to ensure cycler is stable?
Perturbations:
• Energy dissipation
• Radiation forces (solar radiation, reflected solar radiation, magnetic, thermal)
Assumptions:
• Small-spin approximations
• Spin stabilization only
• Cycler vehicle is rigid
Model & Analysis: Spin stabilization
Euler’s Equations [1]:
Small perturbations i.e. small 🡪 :
LHS 🡪 torques, calculated from perturbation forces
Take Laplace transform 🡪 roots of characteristic equations 🡪 stability
[1] Wertz, J. R. (1978). Spacecraft attitude determination and control. Dordrecht: Kluwer Academic Publishers.
Pertubation Force
(Near Earth, flyby)
Magnitude (N)
Solar Radiation 1.308E-2
Reflected Solar Radiation 2.701E-4
Planet Thermal Radiation 1.706E-4
Spacecraft Radiation P/c
Solar Wind 4.41E-6
Meteoroids Negligible
Emily SchottFebruary 6, 2020
Human Factors: TaxiEmergency Preparedness
The Problem(s):
Common issues in commercial travel:
• Medical Issues [1]• Fainting
• Respiratory Symptoms
• Nausea/Vomiting
• Heart Attacks and Seizures
• Misc• Delays
• Weather
Potential issues in space travel:
• Medical Issues• Space Sickness
• Heart Attacks
• Fainting
• Vehicle Malfunctions• Fires
• Leaks
• Launch/Landing Issues
Assume 4 day maximum travel time,
need supplies for trip to cycler and back
The Solutions
Item Mass (kg) Volume (m^3)
2 days of extra food 119.52 0.12
2 days of extra water 960 0.96
FAA FAK, EMK, UPK [2] 1.6 each 0.007 each
AED [3] 1.5 0.01
Fire Extinguisher [4] 3.5 0.01
Sickness bags [5] 2.4 0.01
Totals 1,090.12 1.131
Food and Water estimate: Human Factors, Kait Hauber
Taxi model: Structures, Nicki Liu
5m
15m
5m
Allow for
passenger
cabin to
separate and
perform
vertical landing
Alexey ZeninFebruary 5th, 2020
Discipline: Human FactorsVehicle/Systems: Cycler
Topic: Bioregenerative Life Support System (BLSS)
Problem: Continuous Food Cultivation on Board
Requirements:• The BLSS requires minimum to no inputs
• Sufficient production of O2
• Provision of all necessary nutrients
• Sufficient reduction of CO2
• Minimize Human and Cultivational waste
Objectives:
• Determine BLSS’s output/input requirements
• Estimate mass, power, and area requirements
• Technological and operational Overview
Assumptions:
O2
0.84 kg/day
CO2
1 kg/day
Crew
Member
Human
Waste
Estimations
Air
Bio-fermented
Waste(Fertilizer)BLSS
Oxygen
3.2308 Mg
Inedible
solid mass
Food
22.2 Mg
Michael PorterFebruary 06, 2020
Discipline: Mission DesignVehicle & System: Asteroid Tether Sling
The Problem: Selecting and Designing an Orbit
Problem 1:
Select feasible orbit
Problem 2
Find suitable asteroid
Problem 3
Determine attitude stability
GMAT analysis produced using some initial conditions by Turner [5]
The Solution
Solution 1: Orbital Parameters [3]
Type DRO
X-Amplitude 69,500 km
Resonance 1:1:2
Period 13.785 days (Luna)
Stability Over 100 years
Solution 3: DRO Natural Stability [4]
**Adapted from
figure by Guzzetti
& Howell [4]
BREAKResume at 2:44
Valentin RichardFebruary 6, 2020
Mission Design Asteroid Tether Sling
The problem: How much using an asteroid in the Earth/moon system could be beneficial ?
Assumptions:
➣ The asteroid will be located on a DRO orbit around the moon
➣ The travel times are not taken into account
➣ Cost & feasibility of getting the asteroid on the DRO is not taken into account
Comparative study between different possible paths:
1 ➣ LEO 🡪 DRO 🡪 Earth/Moon Escape
2 ➣ LEO 🡪 Moon 🡪 DRO 🡪 Earth/Moon Escape
3 ➣ LEO 🡪 Cycler
The solution: ∆V estimates Path 1: LEO 🡪 DRO 🡪 Earth/Moon Escape
Maneuver Required ΔV (km/s)
LEO to DRO[1]
1. Intermediate L1-Lyapunov
2. Lunar Far-Side Insertion
3. Close Lunar Flyby
(ED Tether)
[ 3.576 ; 4.334 ]
[ 3.456 ; 3.785 ]
[ 3.365 ; 3.393 ]
DRO to Earth/Moon Escape[2] 1.01 (Asteroid Tether)
Total: [ 4.375 ; 5.344 ]
Path 3: LEO 🡪 Cycler
Maneuver Required ΔV (km/s)
Total[2]: 4.3 (ED Tether)
Path 2: LEO 🡪 Moon 🡪 DRO 🡪 Earth/Moon Escape
LEO to LLO (Hohmann)[3] 3.959 (ED Tether)
LLO to DRO[2] 0.86 (Lunar Tether)
DRO to Earth/Moon Escape[2] 1.01 (Asteroid Tether)
Total: 5.829
To be determined: ∆V to get to the cycler from DRO/Moon
and the Tether Sling’s influence on the asteroid orbital stability
Pierre VEZIN02/01/2020
Mission Design – ElectrDyn. Tether(DeltaV calc, Dynamic Simulation, Orbit degradation)
How will the use of the ED Tether affect the orbit ?
The Problem: Momentum exchange
After SpaceCraft is released :
- S/C ends up with a Boost
- Tether gets slowed down
Requirements :
- Avoid ground at all cost
- Keep the Tether in a stable enough orbit
(high atmoshpere = drag)
Assumptions :
- separation triggered @ 1000 km
- S/C deltaV is prograde
- variables are Mass Ratio and S/C deltaV
Tether after
Release
Payload after
Release
EARTH
How will the use of the ED Tether affect the orbit ?
From a Circular LEO :
- Tethers w/ Mass ratio <= 15 will crash
- W/ tether length of up to 700km: not much margin !
From an elliptical LEO1 (energy stored through height):- Mass ratio can be reduced to 5 or 10 while remaining close to
LEO & w/ Perigee > 1000 km
[1] «Modeling and analyis of the Electrodynamic tether» J.Longuski, M.Mueterthies
M ratio : 10
15 20
M ratio : 10
15
2025
30
Melissa WhitcombFebruary 6, 2020
Mission Design
Orbital ∆v Calculations
∆v and Defining the OrbitsThe Main Objectives:
1. Define the orbits for all 4 cycler vehicles (and any other vehicles we create)
2. Find the ∆v for each path shift in the orbit
3. Find the total TOF for the human passengers on each orbit
The First Challenges:
1. Multiple versions of these calculations on the loose in 450
2. Asteroid characteristics?
3. How to use/open the cycler data?
4. Defining LEO, LLO, LMO, etc.
The Plan:
1. Get rough ∆v’s with Hohmann transfers, and refine via hyperbolic orbits and
Lambert arcs to get upper limits. (MATLAB → GMAT)
2. Condense (and verify) everyone’s ∆v calculations into one spreadsheet for all
teams’ use (Excel)
The Hohmann ∆v Values (minimum requirements)
Assumptions:
• Orbital velocities at LXO altitudes assumed to be
planar.
• LLO altitude taken from Apollo 11 and will need to be
updated with preferred stable orbit.
• Tether is assumed to be on the surface of the body
and not significantly affecting the length of body’s
radius.
• Asteroid is assumed to be of equal size and mass as
Phobos.
Coming Soon:
TOF’s (min & max) and ∆v (max)
Journey segment ∆v min
(km/s)
Earth surface to LEO 4.119
LEO to LLO/Asteroid 3.765
Moon surface to LLO 0.580
LLO to Cycler 1 3.640
Cycler to LMO 0.868
Mars surface to LMO 1.634
LMO to Phobos 1.911
Sources:
[1] NASA Planetary Fact Sheets
https://nssdc.gsfc.nasa.gov/planetary/planetfact.html
[2] ESA Mars Express https://sci.esa.int/web/mars-
express/-/31031-phobos
[3] Dr. Jekan Thanga, Purdue guest lecturer,
1/27/2020.
Peter Salek February 4, 2020
Discipline: Power and ThermalPowering the Mass Driver
1
Problem
Given Parameters
Moon:
Power required – 1.33 GW
Mars:
Power required – 2.66 GW
Mass Driver Efficiency – 90%
Requirements
• Investigate multiple methods of
power generation for the Mass
Driver
• Determine total mass of the system
Assumptions
• Multiple taxi vehicles will need to be
launched in succession
• Interval of 5 minutes between each
launch
2[1] AAE 450, Nicolas Martinez Cruces
[2] Davis, E., & Warp Drive Metrics LAS Vegas Nv. (2004). Advanced Propulsion Study.
[1]
[1]
[2]
Solution
Total Mass of
System
Moon Mars
Solar Panels 58,763 Mg 155,580 Mg
Nuclear Power 54,977 Mg 114,090 Mg
• Large Capacitor Banks to store energy for
each Launch
• Nuclear Reactors to Generate Power on
Both The Moon and Mars
• Power Generation of 10.2 MW on Mars
• Power Generation – 5 MW on The Moon
• Allows for launches regardless of sunlight
Future Power Generation Research
• Investigate using batteries to
store energy for launches
• Investigate Geothermal energy as
another power source on Mars
• Consider increasing time
between launches to decrease
mass
3
Josh SchmeidlerFebruary 6th, 2020
Power & ThermalThermal Analysis of Taxi Vehicle
Taxi Vehicle Heating on Mars Tether Sling
Problem
• Aerodynamic heating due to high speeds within atmosphere
Assumptions
• Tether situated on top of Olympus Mons
• Worst case scenario – 5 km/s flight speed
• Atmospheric entry model used
• Heating from convective and radiative heat transfer
Heating Rate
BREAKResume at 3:20
Joe TiberiFebruary 6th, 2020
Propulsion Team LeadED Tether
Escaping LEO with Electricity
• Investigating spinning tether in LEO
• Main Considerations investigated
• Astronaut accelerations
• Spin-Up/operating times
• Possible power consumptions
• Delta V required: 3.31 km/s
Physics Analysis• Current findings
• Large mass required to be in
LEO (3.4955e6 Kg)
• Very Long tether required
• Maximum Power Required
• ~170 MW
• Next steps
• Investigate traversing the
tether
• Adding in ED force
• Momentum bank size
requirements and lifespan
Shuting YangFebruary 06, 2020
PropulsionPhobos Tether SlingPropellant Analysis
Slide 1 of 3
Problem: Propellant Analysis
Requirement:
• No chemical propellants
Assumptions:
• A tapered tether system is used.
• The safety factor of the tether is 10.
• The maximum acceleration is 3g.
• The spin-up time at 3g is 24 hours.
Current Proposal:
• Use solar panels and batteries to convert and store solar energy from host star
to electric energy.
Analysis Procedures:
L: Tether Length
M: Tether Mass
A: Unit Solar Array Area
g: Gravitational
Acceleration on
Earth’s Surface
Slide 2 of 3
Solution:
23.7339
14.0531
13.3041
11.7481
10.2315
0 5 10 15 20 25
LOX/LH2
NTO/MMH
LOX/RP-1
NTO/Aerozine 50
HTPB
Pro
pella
nt
Type
Mass of Tether / Mass of Propellants
7.8468
4.6462
4.3986
3.8841
3.3827
0 2 4 6 8 10
LOX/LH2
NTO/MMH
LOX/RP-1
NTO/Aerozine 50
HTPB
A (m2)
Pro
pella
nt
Type
Solar Array Area
Slide 3 of 3
Natasha Yarlagadda February 6, 2020
Propulsion TeamTaxi - Mars Landing
56
Problem
Assumptions:- Constant gravity (overestimate)
- Cylindrical Aluminum Lithium alloy propellant tanks
- RP-1 (kerosene) is CH1.97 for chemical balances
- OMS/RCS system help taxi exit Mars orbit and align vertically
Mars Landing Site
vtank
mtank
moxidizer
mfuel
Types of propellant
Power generated
Requirements: Propulsion:
- Chemical propulsion system to decelerate taxi to safe landing speed
- Fthrust, required= 7686000 N[*]
Structures:
- Taxi needs to land vertically on Mars
- Propellant tanks fit within given volume, V = 211.17 m3
Human Factors:
- Reaction by-product provides reusable water
57*See backup slides for required thrust calculation
Solution: LH2 / LOX Propellant System
Propellants Selected LOX (liquid oxygen) LH2 (liquid hydrogen)
Propellant Masses[1] moxidizer= 64.80 Mg mfuel= 10.83 Mg
Tank Volumes[2] vox, tank= 59.63 m3 vfuel, tank= 160.6 m3
Power Generated[3] Fthrust, 1 engine = 2184076 N
Total Specs mtank+prop+engines= 181.9 Mg[4][5] vtank= 255.15 m3 Fthrust, 4 engines= 8736307 N
(Adapted from Space Shuttle RS-25)[6]
LOX LH2
References cited in backup slides58
Rachel RothFebruary 6, 2020
StructuresCommunication Satellites
Slide 1 of 3
Problem – Material Selection and Initial Sizing/Layout
System Requirements
Slide 2 of 3
Power and Thermal
• Solar energy collection and storage
• Thermal control system
Propulsion
• Ion propulsion system
Communications
• Earth relay satellites in GEO
• L4/L5 Lagrange points relay satellites
• Mars relay satellites
Tensile Strength
Thermal Performance
Corrosion Protection
Material Selection Criteria
Solution – Material Selection and Initial Sizing/Layout
Slide 3 of 3
[1] AAE 450 Communications Team
[2] AAE 450 Propulsion Team
[3] AAE 450 Power and Thermal Team
Communications Satellite Initial Sizing
solar panel
*GEO Satellite: 3 RF Antennas + OCS GEO to L4/L5
L4/L5 Satellite: OCS GEO to L4/L5 + OCS L4/L5 to Mars
Mars Satellite: 3 RF Antennas + OCS L4/L5 to Mars [1]
L4/L5
Top-down view Sun
solar panel
GEO/Mars
Top-down viewEarth/
Mars
RF antenna
gimbal
Al 7075-T7351
OCS
OCS
5.5 m
3 m
3 m
Eli Sitchin Backup SlidesFebruary 5, 2020
Discipline: CADVehicle and Systems Group: Cycler
62
Backup Slide: Superstructure Design
Considerations
• Taxis will dock parallel to the axis of rotation, to reduce their
effect on the moment of inertia.
• Taxi docking mechanism not yet designed
• Docking port radius preliminarily set to 2 m [1]
Next Steps
• Determine interior layout (controls, crew transport, etc.)
• Finalize docking port dimensions Docking Port
Radius 10 m
Height 45 m
Docking Port Location (from Bottom of Image) 32.5 m
63
Backup Slide: Habitation Module Design
Considerations
• Minimum safe ceiling radius of 100 m multiplied by SF = 4
• Interior height accommodates adult men of height +6σ [2]
• Interior width accommodates passenger quarters and one
hallway [3]
Next Steps
• Determine interior layout (quarters, galley, exercise area, etc.)
• Research life support requirements
Ceiling Radius 400 m
Interior Height 2.5 m
Interior Width 6 m
Interior-Exterior Distance 1.2 m Roof
Floor
Pressurized Volume 3220 m3
Habitable Volume 1138 m3
Floor Area 456.4 m2
Arc 11.14º
4 Modules Total
64
Backup Slide: Elevator-Habitation Interface Design
Considerations
• Arc designed to ensure sufficient room for elevator and
passage between adjacent habitation modules
• Volume requirements may change if life support/propulsion
equipment stored in the interface
Next Steps
• Determine interior layout
• Research life support/propulsion requirements
Pressurized Volume 2363 m3
Habitable Volume 900.9 m3
Floor Area 362.7 m2
Arc 1.776º
Ceiling Radius 400 m
Interior Height 2.5 m
Interior Length 38 m
Interior-Exterior Distance 1.2 m
2 Modules Total
65
Backup Slide: Elevator/Support Design
Considerations
• Elevator radii based on ISS truss [4] and ADA
elevator guidelines [5].
Next Steps
• Determine structural loads
Support Cross-Sectional Area 1 m2
Elevator Outer Radius 2.5 m
Elevator Inner Radius 2 m
Truss/Elevator Length 388.8 m
8 Supports Total
2 Elevators
Total
66
Backup Slide: MATLAB Code for Minimum Radius
67
Backup Slide: MATLAB Code for Minimum Radius
68
Backup Slide: MATLAB Code for Habitation Dimensions
69
Backup Slide: MATLAB Code for Habitation Dimensions
70
Backup Slide: MATLAB Code for Habitation Dimensions
71
References
[1] “Reference Guide to the International Space Station,” National Aeronautics
and Space Administration, Sep. 2015.
[2] Rosen, M., Appel, C., and Ritchie, H., “Human Height,” Our World in Data,
2019.
[3] “Shreve Room Layout,” Housing at Purdue University Available:
https://www.housing.purdue.edu/Housing/Residences/Shreve/layout.html.
[4] Petty, J. I., “STS-113 Payloads,” National Aeronautics and Space
Administration, Oct. 2002.
[5] “Part 36 - Nondiscrimination on the Basis of Disability by Public
Accommodations and in Commercial Facilities,” Americans With Disabilities
Act, Jul. 1991.
72
Erick Smith: Backup Slides February 6th, 2020
CADLanding Pad(s)
Landing Pad Hub
• Initial concept of the design
Landing Pad
• Initial Concept of the
Landing pad itself, including
unofficial materials used for
the design.
Nicholas DeAngeloFebruary 6th, 2020
Backup CommunicationsTaxi Vehicle (Phobos Tether and Mars Mass
Driver)
Backup – Link Budget MATLAB Script
• [2] [3] [4] Script for Link Budget to find Power required
Backup – Link Budget MATLAB Workspace
• Workspace for Link
Budget MATLAB Script
References
• [1] – AAE 450 Spring 2015 Project Aldrin-Purdue – Report pg. 50-51
• [2] – “Frequency Range Chart,” Amphenol RF Available:
https://www.amphenolrf.com/frequency-range-chart/.
• [3] – “Frequency Range Chart,” Amphenol RF Available:
https://www.amphenolrf.com/frequency-range-chart/.
• [4] – Free Space Path Loss Calculator Available:
https://www.pasternack.com/t-calculator-fspl.aspx.
Sidharth PrasadFebruary 6, 2020
Backup ControlsTaxi Vehicle
Supplementary Slide: Matlab CodeVinf = 5*10^3; % m/s
mu_p = 4.282837*10^13; %m^3/s^2 grav param mars
re = 3389.5*10^3+135*10^3;
Vei = sqrt(Vinf^2+2*mu_p/re);
tspan = [0 1000];
y01 = [re,0,0,Vei,deg2rad(-25),0,0];
y02 = [re,0,0,Vei,deg2rad(-19),0,0];
y03 = [re,0,0,Vei,deg2rad(-14),0,0];
y04 = [re,0,0,Vei,deg2rad(-30),0,0];
[t1,y1] = ode45(@entrydynamics,tspan,y01);
[t2,y2] = ode45(@entrydynamics,tspan,y02);
[t3,y3] = ode45(@entrydynamics,tspan,y03);
[t4,y4] = ode45(@entrydynamics,tspan,y04);
Supplementary Slide: Matlab Code
figure()
plot(y4(:,4)/1000,(y4(:,1)- 3389.5*10^3)/1000)
hold on;
plot(y1(:,4)/1000,(y1(:,1)- 3389.5*10^3)/1000)
plot(y2(:,4)/1000,(y2(:,1)- 3389.5*10^3)/1000)
plot(y3(:,4)/1000,(y3(:,1)- 3389.5*10^3)/1000)
xlabel('Velocity (km/s)');
ylabel('Altitude (km)');
legend('Gamma = -30','Gamma = -25','Gamma = -19', 'Gamma = -14');
grid on;
title('Velocity vs. Altitude for Taxi (BC 150)');
% figure()
% plot(t,(y(:,1)- 3389.5*10^3)/1000);
% xlabel('Time (s)');
% ylabel('Altitude');
% grid on;
% title('Altitude vs. Time for Taxi (BC 300, Gamma -16)');
Supplementary Slide: Matlab Codefunction rho = density(r)
r_mars = 3389.5*10^3; % in m
alt = r-r_mars; %altitude
rho = 0.013*exp(-alt/11000); %(1/0.013)*e^alt; % density in kg/m^3
end
function dydt=entrydynamics(t,y)
%y(r,theta,phi,V,gamma,psi,s)
%dydt (rdot,thetadot,psidot,Vdot,gammadot,psidotsd0t)
sigma = 0;% bank angle
q = 1/2*density(y(1))*y(4)^2;%dynamic pressure
m = 22633.00; % vehicle mass
CD = 1.7;%coeff drag
A = 50;%Ref Area approx of space shuttle lander
LD = 0; % 0.8 % Lift/Drag approximated from space shuttle
Beta = 200; %m / (CD*A)%Ballistic Coefficient
mu_p = 4.282837*10^13; %m^3/s^2 grav param mars
gr = -mu_p/y(1)^2;%radial grav component
Supplementary Slide: Matlab Code
dydt(1)= y(4)*sin(y(5));
dydt(2)= y(4)*cos(y(5))*cos(y(6))/(y(1)*cos(y(3)));
dydt(3)= y(4)*cos(y(5))*cos(y(6))/(y(1));
dydt(4)= -q/Beta + gr*sin(y(5));
dydt(5)= (q*LD)/(y(4)*Beta)*cos(sigma) + 1/y(4)*(gr*cos(5)) +
(y(4)*cos(y(5))/y(1));
dydt(6)= (q*LD)/(y(4)*Beta)*sin(sigma)/cos(y(4)) -
y(4)/y(1)*cos(y(5))*cos(y(6))*tan(y(3));
dydt(7)= y(4)*cos(y(5));
dydt = dydt';
end
Brady WalterFebruary 6, 2020
ControlsAnalysis of Communication Satellite Control:
Backup Slides
Sources
Barret, C. “Spacecraft Flight Control System Design Selection Process for a
Geostationary Communication Satellite”, Marshall Space Flight Center, Alabama:
Sept. 1992. Accessed via
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930001814.pdf
“RSI 12 Momentum and Reaction Wheels”, Collins Aerospace, 2020. Accessed
5 Feb 2020. Accessed via https://www.rockwellcollins.com/Products-and-
Services/Defense/Platforms/Space/RSI-12-Momentum-and-Reaction-
Wheels.aspx
Beverley K.W. YeoFebruary 6th, 2020
Backup - ControlsCycler – Stability Analysis
Appendix: Perturbation Force Calculation
Perturbation Force Values based on Near-Earth flyby (N) [2] Magnitude (N)
Solar Radiation 9.2E-5 1.308E-2
Reflected Solar Radiation 1.9E-5 2.701E-4
Planet Thermal Radiation 1.2E-5 1.706E-4
Spacecraft Radiation 2.7E-7 P/c
Solar Wind 3.1E-8 4.41E-6
Meteoroids 4.9E-10 Negligible
• Scaled according to area ratio , cycler area based on L =
120m, W = 15.65m (from CAD)
[2] Longuski, J. M., Todd, R. E., & Konig, W. W. (1992). Survey of nongravitational forces and space environmental
torques - Applied to the Galileo. Journal of Guidance, Control, and Dynamics, 15(3), 545–553. doi: 10.2514/3.20874
Alexey ZeninFebruary 5th, 2020
Backup Slides
Backup Slides
Backup Slides
Backup Slides
Backup Slides
Backup Slides
Backup Slides
Backup Slides
References:
Alamaro M. 2007. Large-scale greenhouses attached to power plants for the productive use of
waste heat and CO2 emissions. Copyright#Moshe Alamaro 2007
alamaro.home.comcast.net/alamaro/Greenhouse Concept.pdf
Barlow P. 1996. An introduction to gravity perception in plants and fungia multiplicity of mechanisms.
Adv Space Res. 17:6972.
Bartsev SI, Gitelson JI, Lisovsky GM, Mezhevikin VV, Okhonin VA. 1996. Perspectives of
different type biological life support systems (BLSS) usage in space missions. Acta
Astronautica. 39(8):617622.
Tako Y, Masuda T, Tani T, Shinohara M, Abe K, Arai R, Suzuki M, Tsuga S, Komotsubara O, Nozoe S,
Aibe Y. 2008. On a Japanese bioregenerative life support programThe Mini-earth
projectoverview of the Closed Ecology Experiment Facilities (CEEF), some results from
experiments including closed human habitation and circulation of air and water, and future
plan of experiments using the CEEF. Presented at Workshop on Bioregenerative
Environmental Control State-of-the-art and Trends; 1820 December; Torino, Italy.
Michael Porter – BackupFebruary 06, 2020
Discipline: Mission DesignVehicle & System: Asteroid Tether Sling
DRO vs. Halo Analysis
***All analysis comes from notes taken speaking to Brian McCarthy, Masters Thesis on Halo orbits
DRO Detailed Analysis• DRO’s in the 60,000-70,000 km amplitude have
shown immense stability during 30 year sims. [1]
• A DRO of 61,500 km has shown stability for over 500
years (no station keeping required to maintain orbit)
while accounting for perturbing forces via solar,
Earth, Venus, Jupiter, solar radiation pressure and
asymmetric lunar gravity field [1]. Not chosen due to
unstable natural attitude. [4]
• Analysis run via GMAT has confirmed the current
DRO stability for a 100 year span accounting for
asymmetric lunar gravity field, solar, Saturn, Jupiter,
Earth gravity fields, and SRP.
• 1:1:2 period means the Moon passes the Earth once
every time the spacecraft passes the Earth once, but
the spacecraft will cross between the Moon and
Earth twice in this time .
Solution 1: Orbit Parameters [3]
Type DRO
X-Amplitude 69,500 km
Resonance 1:1:2
Period 13.785 days (Luna)
Stability Over 100 years
433 Eros (A898 PA) Orbital Elements
***All Orbital Elements are taken from JPL [2]
and recreated in GMAT
References[1] Bezrouk, C. J., Parker, J., “Long Duration Stability of Distant Retrograde Orbits,” AIAA, published
online 01 Aug. 2014
https://doi.org/10.2514/6.2014-4424
[2] Chodas, P., “NEO Earth Close Approaches,” JPL Close Approach Database, retrieved 03 Feb. 2020
https://cneos.jpl.nasa.gov/ca/
[3] Conte, D., Di Carlo, M., Ho, K., Spencer, D., Vasile, M., “Earth-Mars transfers through Moon Distant
Retrograde Orbits,” Acta Astronautica, Vol. 143, Feb. 2018, pp. 372-379
https://doi.org/10.1016/j.actaastro.2017.12.007
[4] Guzzetti, D., Howell, K., “Natural periodic orbit-attitude behaviors for rigid bodies in three-body
periodic orbits,” Acta Astronautica, Vol. 130, Jan.-Feb. 2017, pp. 97-130
https://doi.org/10.1016/j.actaastro.2016.06.025
[5] Turner, G., “Results of Long-Duration Simulation of Distant Retrograde Orbits,” Journal of
Aerospace, published online 08 Nov. 2016
https://pdfs.semanticscholar.org/e6ae/ca6ab0ddccb718c3d6ba24b57fcf5f4a9a57.pdf
GMAT Code DRO modeling
%General Mission Analysis Tool(GMAT) Script
%Created: 2020-01-29 21:48:50
%----------------------------------------
%---------- Spacecraft
%----------------------------------------
Create Spacecraft DefaultSC;
GMAT DefaultSC.DateFormat = UTCGregorian;
GMAT DefaultSC.Epoch = '07 Jan 2016 11:59:28.000';
GMAT DefaultSC.CoordinateSystem = moon;
GMAT DefaultSC.DisplayStateType = Cartesian;
GMAT DefaultSC.X = -61499.99999999993;
GMAT DefaultSC.Y = -4.092726157978177e-012;
GMAT DefaultSC.Z = 7.275957614183426e-012;
GMAT DefaultSC.VX = -1.908195823574488e-016;
GMAT DefaultSC.VY = 0.4999999999999994;
GMAT DefaultSC.VZ = -1.734723475976807e-017;
GMAT DefaultSC.DryMass = 687000000000000;
GMAT DefaultSC.Cd = 2.2;
GMAT DefaultSC.Cr = 1.8;
GMAT DefaultSC.DragArea = 15;
GMAT DefaultSC.SRPArea = 1;
GMAT DefaultSC.NAIFId = -10001001;
GMAT DefaultSC.NAIFIdReferenceFrame = -9001001;
GMAT DefaultSC.OrbitColor = Red;
GMAT DefaultSC.TargetColor = Teal;
GMAT DefaultSC.OrbitErrorCovariance = [ 1e+070 0 0 0 0 0 ; 0
1e+070 0 0 0 0 ; 0 0 1e+070 0 0 0 ; 0 0 0 1e+070 0 0 ; 0 0 0 0
1e+070 0 ; 0 0 0 0 0 1e+070 ];
GMAT DefaultSC.CdSigma = 1e+070;
GMAT DefaultSC.CrSigma = 1e+070;
GMAT DefaultSC.Id = 'SatId';
GMAT DefaultSC.Attitude = CoordinateSystemFixed;
GMAT DefaultSC.SPADSRPScaleFactor = 1;
GMAT DefaultSC.ModelFile = 'aura.3ds';
GMAT DefaultSC.ModelOffsetX = 0;
GMAT Code DRO modeling
GMAT DefaultSC.ModelOffsetY = 0;
GMAT DefaultSC.ModelOffsetZ = 0;
GMAT DefaultSC.ModelRotationX = 0;
GMAT DefaultSC.ModelRotationY = 0;
GMAT DefaultSC.ModelRotationZ = 0;
GMAT DefaultSC.ModelScale = 1;
GMAT DefaultSC.AttitudeDisplayStateType = 'Quaternion';
GMAT DefaultSC.AttitudeRateDisplayStateType =
'AngularVelocity';
GMAT DefaultSC.AttitudeCoordinateSystem =
EarthMJ2000Eq;
GMAT DefaultSC.EulerAngleSequence = '321’;
%----------------------------------------
%---------- ForceModels
%----------------------------------------
Create ForceModel Propagator1_ForceModel;
GMAT Propagator1_ForceModel.CentralBody = Earth;
GMAT Propagator1_ForceModel.PrimaryBodies = {Earth};
GMAT Propagator1_ForceModel.PointMasses = {Luna, Sun};
GMAT Propagator1_ForceModel.Drag = None;
GMAT Propagator1_ForceModel.SRP = Off;
GMAT Propagator1_ForceModel.RelativisticCorrection = Off;
GMAT Propagator1_ForceModel.ErrorControl = RSSStep;
GMAT Propagator1_ForceModel.GravityField.Earth.Degree =
4;
GMAT Propagator1_ForceModel.GravityField.Earth.Order = 4;
GMAT Propagator1_ForceModel.GravityField.Earth.StmLimit =
100;
GMAT
Propagator1_ForceModel.GravityField.Earth.PotentialFile =
'JGM2.cof';
GMAT Propagator1_ForceModel.GravityField.Earth.TideModel
= 'None';
%----------------------------------------
%---------- ForceModels
%----------------------------------------
Create ForceModel DefaultProp_ForceModel;
GMAT Code DRO modeling
GMAT DefaultProp_ForceModel.CentralBody = Luna;
GMAT DefaultProp_ForceModel.PrimaryBodies = {Luna};
GMAT DefaultProp_ForceModel.PointMasses = {Earth, Sun};
GMAT DefaultProp_ForceModel.Drag = None;
GMAT DefaultProp_ForceModel.SRP = Off;
GMAT DefaultProp_ForceModel.RelativisticCorrection = Off;
GMAT DefaultProp_ForceModel.ErrorControl = RSSStep;
GMAT DefaultProp_ForceModel.GravityField.Luna.Degree = 4;
GMAT DefaultProp_ForceModel.GravityField.Luna.Order = 4;
GMAT DefaultProp_ForceModel.GravityField.Luna.StmLimit =
100;
GMAT
DefaultProp_ForceModel.GravityField.Luna.PotentialFile =
'LP165P.cof';
GMAT DefaultProp_ForceModel.GravityField.Luna.TideModel
= 'None';
%----------------------------------------
%---------- Propagators
%----------------------------------------
Create Propagator DefaultProp;
GMAT DefaultProp.FM = DefaultProp_ForceModel;
GMAT DefaultProp.Type = RungeKutta89;
GMAT DefaultProp.InitialStepSize = 60;
GMAT DefaultProp.Accuracy = 9.999999999999999e-012;
GMAT DefaultProp.MinStep = 0.001;
GMAT DefaultProp.MaxStep = 2700;
GMAT DefaultProp.MaxStepAttempts = 50;
GMAT DefaultProp.StopIfAccuracyIsViolated = true;
%----------------------------------------
%---------- Coordinate Systems
%----------------------------------------
Create CoordinateSystem moon;
GMAT moon.Origin = Luna;
GMAT Code DRO modeling
GMAT moon.Axes = ObjectReferenced;
GMAT moon.XAxis = R;
GMAT moon.ZAxis = N;
GMAT moon.Primary = Earth;
GMAT moon.Secondary = Luna;
Create CoordinateSystem moon_fixed;
GMAT moon_fixed.Origin = Luna;
GMAT moon_fixed.Axes = BodyFixed;
Create CoordinateSystem sun_fix;
GMAT sun_fix.Origin = Sun;
GMAT sun_fix.Axes = BodyFixed;
Create CoordinateSystem asteroid_frame;
GMAT asteroid_frame.Origin = DefaultSC;
GMAT asteroid_frame.Axes = BodyFixed;
%----------------------------------------
%---------- Subscribers
%----------------------------------------
Create OrbitView DefaultOrbitView;
GMAT DefaultOrbitView.SolverIterations = Current;
GMAT DefaultOrbitView.UpperLeft = [ 0.004705882352941176
0.002534854245880862 ];
GMAT DefaultOrbitView.Size = [ 0.4994117647058823
0.4486692015209126 ];
GMAT DefaultOrbitView.RelativeZOrder = 898;
GMAT DefaultOrbitView.Maximized = false;
GMAT DefaultOrbitView.Add = {DefaultSC, Earth, Luna};
GMAT DefaultOrbitView.CoordinateSystem = moon;
GMAT DefaultOrbitView.DrawObject = [ true true true ];
GMAT DefaultOrbitView.DataCollectFrequency = 1;
GMAT DefaultOrbitView.UpdatePlotFrequency = 50;
GMAT DefaultOrbitView.NumPointsToRedraw = 0;
GMAT DefaultOrbitView.ShowPlot = true;
GMAT DefaultOrbitView.MaxPlotPoints = 20000;
GMAT Code DRO modeling
GMAT DefaultOrbitView.ShowLabels = true;
GMAT DefaultOrbitView.ViewPointReference = Luna;
GMAT DefaultOrbitView.ViewPointVector = [ 0 0 950000 ];
GMAT DefaultOrbitView.ViewDirection = Luna;
GMAT DefaultOrbitView.ViewScaleFactor = 1;
GMAT DefaultOrbitView.ViewUpCoordinateSystem =
EarthMJ2000Eq;
GMAT DefaultOrbitView.ViewUpAxis = Z;
GMAT DefaultOrbitView.EclipticPlane = Off;
GMAT DefaultOrbitView.XYPlane = Off;
GMAT DefaultOrbitView.WireFrame = Off;
GMAT DefaultOrbitView.Axes = On;
GMAT DefaultOrbitView.Grid = Off;
GMAT DefaultOrbitView.SunLine = Off;
GMAT DefaultOrbitView.UseInitialView = On;
GMAT DefaultOrbitView.StarCount = 7000;
GMAT DefaultOrbitView.EnableStars = Off;
GMAT DefaultOrbitView.EnableConstellations = On;
%----------------------------------------
%---------- Subscribers
%----------------------------------------
Create OrbitView DefaultOrbitView2;
GMAT DefaultOrbitView2.SolverIterations = Current;
GMAT DefaultOrbitView2.UpperLeft = [ 0.01588235294117647
0.6514575411913816 ];
GMAT DefaultOrbitView2.Size = [ 0.4947058823529412
0.4385297845373891 ];
GMAT DefaultOrbitView2.RelativeZOrder = 903;
GMAT DefaultOrbitView2.Maximized = false;
GMAT DefaultOrbitView2.Add = {DefaultSC, Earth, Luna};
GMAT DefaultOrbitView2.CoordinateSystem = EarthFixed;
GMAT DefaultOrbitView2.DrawObject = [ true true true ];
GMAT DefaultOrbitView2.DataCollectFrequency = 1;
GMAT DefaultOrbitView2.UpdatePlotFrequency = 50;
GMAT DefaultOrbitView2.NumPointsToRedraw = 0;
GMAT DefaultOrbitView2.ShowPlot = true;
GMAT Code DRO modeling
GMAT DefaultOrbitView2.MaxPlotPoints = 20000;
GMAT DefaultOrbitView2.ShowLabels = true;
GMAT DefaultOrbitView2.ViewPointReference = Earth;
GMAT DefaultOrbitView2.ViewPointVector = [ 0 0 550000 ];
GMAT DefaultOrbitView2.ViewDirection = Earth;
GMAT DefaultOrbitView2.ViewScaleFactor = 1;
GMAT DefaultOrbitView2.ViewUpCoordinateSystem =
EarthMJ2000Eq;
GMAT DefaultOrbitView2.ViewUpAxis = Z;
GMAT DefaultOrbitView2.EclipticPlane = Off;
GMAT DefaultOrbitView2.XYPlane = Off;
GMAT DefaultOrbitView2.WireFrame = Off;
GMAT DefaultOrbitView2.Axes = On;
GMAT DefaultOrbitView2.Grid = Off;
GMAT DefaultOrbitView2.SunLine = Off;
GMAT DefaultOrbitView2.UseInitialView = On;
GMAT DefaultOrbitView2.StarCount = 7000;
GMAT DefaultOrbitView2.EnableStars = Off;
GMAT DefaultOrbitView2.EnableConstellations = On;
%----------------------------------------
%---------- Subscribers
%----------------------------------------
Create OrbitView DefaultOrbitView3;
GMAT DefaultOrbitView3.SolverIterations = Current;
GMAT DefaultOrbitView3.UpperLeft = [ 0.5023529411764706
0.2002534854245881 ];
GMAT DefaultOrbitView3.Size = [ 0.4941176470588236
0.4372623574144487 ];
GMAT DefaultOrbitView3.RelativeZOrder = 1031;
GMAT DefaultOrbitView3.Maximized = false;
GMAT DefaultOrbitView3.Add = {DefaultSC, Earth, Luna};
GMAT DefaultOrbitView3.CoordinateSystem =
EarthMJ2000Eq;
GMAT DefaultOrbitView3.DrawObject = [ true true true ];
GMAT DefaultOrbitView3.DataCollectFrequency = 1;
GMAT Code DRO modeling
GMAT DefaultOrbitView3.UpdatePlotFrequency = 50;
GMAT DefaultOrbitView3.NumPointsToRedraw = 0;
GMAT DefaultOrbitView3.ShowPlot = true;
GMAT DefaultOrbitView3.MaxPlotPoints = 20000;
GMAT DefaultOrbitView3.ShowLabels = true;
GMAT DefaultOrbitView3.ViewPointReference = Earth;
GMAT DefaultOrbitView3.ViewPointVector = [ 0 0 950000 ];
GMAT DefaultOrbitView3.ViewDirection = Earth;
GMAT DefaultOrbitView3.ViewScaleFactor = 1;
GMAT DefaultOrbitView3.ViewUpCoordinateSystem =
EarthMJ2000Eq;
GMAT DefaultOrbitView3.ViewUpAxis = Z;
GMAT DefaultOrbitView3.EclipticPlane = Off;
GMAT DefaultOrbitView3.XYPlane = Off;
GMAT DefaultOrbitView3.WireFrame = Off;
GMAT DefaultOrbitView3.Axes = On;
GMAT DefaultOrbitView3.Grid = Off;
GMAT DefaultOrbitView3.SunLine = Off;
GMAT DefaultOrbitView3.UseInitialView = On;
GMAT DefaultOrbitView3.StarCount = 7000;
GMAT DefaultOrbitView3.EnableStars = Off;
GMAT DefaultOrbitView3.EnableConstellations = On;
%----------------------------------------
%---------- Subscribers
%----------------------------------------
Create OrbitView DefaultOrbitView4;
GMAT DefaultOrbitView4.SolverIterations = Current;
GMAT DefaultOrbitView4.UpperLeft = [ 0.5029411764705882
0.006337135614702154 ];
GMAT DefaultOrbitView4.Size = [ 0.4941176470588236
0.5247148288973385 ];
GMAT DefaultOrbitView4.RelativeZOrder = 908;
GMAT DefaultOrbitView4.Maximized = false;
GMAT DefaultOrbitView4.Add = {DefaultSC, Earth, Luna};
GMAT DefaultOrbitView4.CoordinateSystem = sun_fix;
GMAT Code DRO modeling
GMAT DefaultOrbitView4.DrawObject = [ false true false ];
GMAT DefaultOrbitView4.DataCollectFrequency = 1;
GMAT DefaultOrbitView4.UpdatePlotFrequency = 50;
GMAT DefaultOrbitView4.NumPointsToRedraw = 0;
GMAT DefaultOrbitView4.ShowPlot = true;
GMAT DefaultOrbitView4.MaxPlotPoints = 20000;
GMAT DefaultOrbitView4.ShowLabels = true;
GMAT DefaultOrbitView4.ViewPointReference = Sun;
GMAT DefaultOrbitView4.ViewPointVector = [ 0 0 398000000 ];
GMAT DefaultOrbitView4.ViewDirection = Sun;
GMAT DefaultOrbitView4.ViewScaleFactor = 1;
GMAT DefaultOrbitView4.ViewUpCoordinateSystem = sun_fix;
GMAT DefaultOrbitView4.ViewUpAxis = Z;
GMAT DefaultOrbitView4.EclipticPlane = Off;
GMAT DefaultOrbitView4.XYPlane = Off;
GMAT DefaultOrbitView4.WireFrame = Off;
GMAT DefaultOrbitView4.Axes = Off;
GMAT DefaultOrbitView4.Grid = Off;
GMAT DefaultOrbitView4.SunLine = Off;
GMAT DefaultOrbitView4.UseInitialView = On;
GMAT DefaultOrbitView4.StarCount = 7000;
GMAT DefaultOrbitView4.EnableStars = Off;
GMAT DefaultOrbitView4.EnableConstellations = On;
%----------------------------------------
%---------- Subscribers
%----------------------------------------
Create OrbitView DefaultOrbitView5;
GMAT DefaultOrbitView5.SolverIterations = Current;
GMAT DefaultOrbitView5.UpperLeft = [ 0.5011764705882353
0.5627376425855514 ];
GMAT DefaultOrbitView5.Size = [ 0.4935294117647059
0.4359949302915083 ];
GMAT DefaultOrbitView5.RelativeZOrder = 1035;
GMAT DefaultOrbitView5.Maximized = true;
GMAT Code DRO modeling
GMAT DefaultOrbitView5.Add = {DefaultSC, Earth, Luna};
GMAT DefaultOrbitView5.CoordinateSystem = asteroid_frame;
GMAT DefaultOrbitView5.DrawObject = [ true true true ];
GMAT DefaultOrbitView5.DataCollectFrequency = 1;
GMAT DefaultOrbitView5.UpdatePlotFrequency = 50;
GMAT DefaultOrbitView5.NumPointsToRedraw = 0;
GMAT DefaultOrbitView5.ShowPlot = true;
GMAT DefaultOrbitView5.MaxPlotPoints = 20000;
GMAT DefaultOrbitView5.ShowLabels = true;
GMAT DefaultOrbitView5.ViewPointReference = Luna;
GMAT DefaultOrbitView5.ViewPointVector = DefaultSC;
GMAT DefaultOrbitView5.ViewDirection = Luna;
GMAT DefaultOrbitView5.ViewScaleFactor = 1;
GMAT DefaultOrbitView5.ViewUpCoordinateSystem =
EarthMJ2000Eq;
GMAT DefaultOrbitView5.ViewUpAxis = Z;
GMAT DefaultOrbitView5.EclipticPlane = Off;
GMAT DefaultOrbitView5.XYPlane = Off;
GMAT DefaultOrbitView5.WireFrame = Off;
GMAT DefaultOrbitView5.Axes = On;
GMAT DefaultOrbitView5.Grid = Off;
GMAT DefaultOrbitView5.SunLine = Off;
GMAT DefaultOrbitView5.UseInitialView = On;
GMAT DefaultOrbitView5.StarCount = 7000;
GMAT DefaultOrbitView5.EnableStars = Off;
GMAT DefaultOrbitView5.EnableConstellations = On;
%----------------------------------------
%---------- Mission Sequence
%----------------------------------------
BeginMissionSequence;
Propagate DefaultProp(DefaultSC) {DefaultSC.ElapsedDays =
100};
Valentin RichardFebruary 6, 2020
Mission Design Asteroid Tether Sling
Backup slide: References
[1] Lucia Capdevilla, David Guzzetti and Kathleen C. Howell, “Various transfer options from Earth to
Distant Retrograde Orbits in the vicinity of the Moon”, AAS 14-167
[2] David Conte, Marilena Di Carlo, Koki Ho, David B. Spencer and Massimiliano Vasile, “Earth-Mars
transfers through Moon Distant Retrograde Orbits”, Acta Astronautica, Volume 143, February 2018,
Pages 372-379
[3] Henry J. Pernicka, Steven M. Marsh, Theodore H. Sweetser and Deborah I. Scarberry, “A Search for
Low AV Earth-to-Moon Trajectories”, AIAA/AASA Astrodynamics Conference, Scottsdale (Arizona),
August 1994
Backup slide: Paths Additional info
LEO To DRO Time Of Flight (TOF) ESTIMATES[2]:
Path TOF (in days)
Lunar Near-Side Insertion (L1
Lyapunov)
LEO Departure maneuver: [ 4.15 ; 5.67 ]
Time spent in L1 Lyapunov: [ 5.84 ; 9.40 ]
DRO Insertion maneuver : Impulsive
Total: [ 9.99 ; 15.07 ]
Lunar Far-Side Insertion LEO Departure maneuver: [ 5.19 ; 10.90 ]
DRO Insertion maneuver : Impulsive
Total : [ 5.19 ; 10.90 ]
Close Lunar Flyby Insertion Only data found: Lunar DRO at C (Jacobi Constant) = 2.91
Total : 21.394
Backup slide: Asteroid Tether Dimensions estimateThe datas have been computed via my
own MATLAB Code, which can be found
on the next page.
A factor of safety = 10 is used for the
calculations, which explains why the
values are that high.
The ∆V used is 2.8 km/s and is a rough
first estimate of the ∆V needed for going
from DRO to Cycler. This value will be
updated as soon as we find a more
precise value.
However, computing these estimate
values can still be interesting to estimate
the order of magnitude of the different
parameters.
Asteroid Tether Sling dimensions
Maximum radial acceleration 3g
Material info (given by
structures team)
Dyneema
UTS = 3.325 Gpa
Density = 970 kg/m3
Tether length 319.8 km
Tether area: - Hub
- Tip
616.4 m2
6.7 * 10-3 m2
Tether mass 5.011 * 1010 kg
Maximum centripetal force 2214 kN
Backup slide: MATLAB Code
Melissa WhitcombFebruary 6, 2020
Mission Design
Orbital ∆v Calculations BACKUP SLIDES
Mass (kg)
Volumetric Mean
Radius (m)
Avg Distance
from surface of
parent body (m)
Altitude from
surface (m) at
LXO
Orbital Velocity
at LO altitude
(m/s)
Semimajor axis
a of orbit
between
Earth 5.97E+24 6371000 N/A 1000000 7,352.2
Luna 7.35E+22 1737400 382000000 110000 1,629.0
Mars 6.42E+23 3389500 N/A 400000 3,361.0
Phobos 1.06E+16 11033 5989000 0 8.0
Asteroid 1.06E+16 11033 LLO? 0 8.0
*assume m_A ~
m_P
Grav Constant, G
= 6.67E-11
LEO to LLO (the
asteroid)
Earth surface
to LEO
LLO to/from
lunar surface
LLO (asteroid)
to cycler Cycler to LMO
LMO to/from
Mars surface LMO to Phobos
m Rp = 7371000 Over the life of Over the life of 3789500
m Ra = 388481000 cycler 1, the cycler 1, the 9389533
m/s vt1 = 10300
DeltaV
expended
DeltaV
expended 4755
m/s Delta_V1 = 2948 goes from goes from 1394
m/s vt2 = 195 2.591 to 4.371, 0.09 to 1.639, 1620
m/s Vaph = 1013 with an average with an average 2136
m/s Delta_V2 = 817 of of 516
m/s Total DeltaV= 3765 4119 580 1634 1911
depends greatly
on the rocket's
acceleration
depends greatly
on the rocket's
acceleration
depends greatly
on the rocket's
acceleration
km/s Total DeltaV= 3.765 4.119 0.580 3.64041 0.868 1.634 1.911
Further calculations for ∆v
∆v and Defining the OrbitsThe Main Objectives:
1. Define the orbits for all 4 cycler vehicles (and any other vehicles we create)
2. Find the ∆v for each path shift in the orbit
3. Find the total TOF for the human passengers on each orbit
The First Challenges:
1. Multiple versions of these calculations on the loose in 450
2. Asteroid characteristics?
3. How to use/open the cycler data?
4. Defining LEO, LLO, LMO, etc.
The Plan:
1. Get rough ∆v’s with Hohmann transfers, and refine via hyperbolic orbits and
Lambert arcs to get upper limits. (MATLAB → GMAT)
2. Condense (and verify) everyone’s ∆v calculations into one spreadsheet for all
teams’ use (Excel)
Cycler 1 additions for ∆v calculation
# Date (m/d/y) Vinf Mag (km/s) Vinf x Vinf y Vinf z Altitude (km) TOF (days)DV per Segment (m/s)
DV per Cycle (m/s)
LLO to cyc delta v
LMO to
Cycl delta v
E-1 6/30/2020 4.22 3.46477 2.400842 0.20985 0 -2.591
M-2 12/15/2020 4.2 3.622656 1.933584 -0.878819 10642 168 0 -0.839
E-3 5/24/2023 5.91 4.902702 2.980457 1.397518 24853 890 0 -4.281
E-4 11/11/2024 5.92 3.567176 4.728563 0.001682 28290 537 0 0 -4.291
M-5 6/10/2025 3.37 -2.396001 2.366752 0.110712 16336 210 0 -0.009
E-6 8/15/2027 6 -2.331498 5.374726 -1.294772 26683 797 0 -4.371
E-7 1/31/2029 6 -4.122487 4.359484 -0.001202 52902 534 125 120 -4.371
M-8 9/18/2029 3.79 -3.585596 0.153237 1.231092 2706 230 0 -0.429
E-9 11/8/2032 4.44 -4.110094 -1.380301 0.979075 5027 1147 0 -2.811
E-10 5/6/2033 4.36 -0.239992 0.214641 -4.351776 5810 179 0 0 -2.731
M-11 9/15/2033 5 1.130976 -4.869649 -0.086068 1799 132 0 -1.639
E-12 3/2/2037 4.57 0.924994 -2.636173 -3.617045 28961 1264 98 -2.941
E-13 9/4/2037 4.5 -0.119045 -0.326172 4.481967 8887 186 0 100 -2.871
M-14 4/15/2038 2.53 0.854312 2.128033 -1.080243 1861 223 0 0.831
E-15 6/15/2040 6 3.516642 4.632249 -1.469633 22929 792 324 -4.371
E-16 12/3/2041 6 1.627477 5.77506 0.001464 30716 536 70 390 -4.371
M-17 6/10/2042 4.55 -4.243753 1.593782 0.416359 14512 189 0 -1.189
E-18 9/4/2044 6 -4.05995 4.228187 -1.28033 26408 817 0 -4.371
E-19 2/24/2046 6 -5.530367 2.327023 -0.001879 67547 538 8 10 -4.371
M-20 8/6/2046 5 -3.894554 -3.049263 0.731057 17025 163 0 -1.639
E-21 11/9/2049 5.2 -4.667327 -2.075194 0.979076 1556 1191 22 -3.571
E-22 5/8/2050 5.11 -0.311251 0.295232 -5.087072 24056 179 0 20 -3.481
M-23 12/31/2050 3.73 1.465533 -2.720309 2.082792 1107 237 0 -0.369
E-24 3/28/2054 4.68 4.341338 -1.754439 -0.112275 1000 1183 131 -3.051
E-25 9/30/2054 4.67 0.044935 -0.376601 4.654238 5810 186 0 130 -3.041
M-26 4/26/2055 3.3 -1.05132 3.08039 -0.563101 0 208 0
min -2.591 0.831
max -4.371 -1.639
average -3.640412 -0.868
• The last two columns on the
right detail the ∆v between the
Cycler 1 vehicle and the
planetary orbit.
• Since the Cycler vehicle goes
at different speeds at different
encounters, our ∆v changes
as well.
• Averages were used in the
presentation to the class
Peter Salek February 4, 2020
Discipline: Power and ThermalPowering the Mass Driver
1
Code
[3] Rani, J., Thangavel, R., Oh, S.-I., Lee, Y., and Jang, J.-H., “An Ultra-High-
Energy Density Supercapacitor; Fabrication Based on Thiol-functionalized
Graphene Oxide Scrolls,” Nanomaterials, vol. 9, 2019, p. 148.
[3]
Josh SchmeidlerFebruary 6th, 2020
Power & ThermalThermal Analysis of Taxi Vehicle
Backup Slides
MATLAB Code References
[1] Benson, Tom. “Mars Atmosphere Model - Metric Units.” NASA, NASA,
12 Nov. 2014, www.grc.nasa.gov/WWW/K-12/rocket/atmosmrm.html.
[2] Girija, Athul Pradeepkumar, et al. “Feasibility and Mass-Benefit Analysis of
Aerocapture for Missions to Venus.” Journal of Spacecraft and Rockets, vol. 57,
no. 1, 24 Jan. 2020, pp. 58–73., doi:10.2514/1.a34529.
Joe TiberiFebruary 6th, 2020
Backup - Propulsion Team LeadED Tether
Calculation MethodsTether Velocity During Spinup
Power required during spinup
Matlab Scripts
Shuting YangFebruary 06, 2020
PropulsionPhobos Tether Sling
Backup Slides
Slide 1 of 6
Appendix A: References
1. Koppel, R.C., “Optimal Specific Impulse of Electric Propulsion”, Second European
Spacecraft Propulsion Conference, Edited by Michael Perry. ESA SP-398. Paris:
European Space Agency, 1997., p.137. Retrieved February 1, 2020 from
http://articles.adsabs.harvard.edu//full/1997ESASP.398..131K/0000137.000.html
2. Puig-Suari, J., Longuski, J.M., and Tragresser, S.G., “A Tether Sling for Lunar and
Interplanetary Exploration,” Acta Astronautica, Vol. 36, No. 6, 1995, pp. 291-296.
3. Redd, N. T. (2017, December 8). Phobos: Facts About the Doomed Martian Moon.
Retrieved February 3, 2020, from https://www.space.com/20346-phobos-moon.html
4. Robert, A. (2008). Rocket Propellants. Retrieved February 3, 2020, from
http://www.braeunig.us/space/propel.htm
5. “Ultra High molecular Weight Polyethylene fiber from DSM Dyneema,” eurofibers,
CIS YA100, January 2010.
Slide 2 of 6
Appendix B: MATLAB Code
Slide 3 of 6
Appendix B: MATLAB Code
Slide 4 of 6
Appendix B: MATLAB Code
Slide 5 of 6
Appendix B: MATLAB Code
Slide 6 of 6
Natasha Yarlagadda - Backup Slides February 6, 2020
Propulsion TeamTaxi - Mars Landing
133
Backup: Initial System Studies
Mission System System Weight (Mg) Engine Propellant
Thrust
(N) Isp (s)
Engine
Weight (Mg)
Mars Insight
Thrusters during atm entry,
parachute descent, 12 descent
engines 0.61
Aerojet Rocketdyne
MR-107K Hydrazine 222.4 226 0.00091
Mars PathfinderAeroshell entry capsule, supersonic
parachute, 3 solid rockets 0.89 Solid tractor rockets N/A N/A N/A N/A
Mars CuriosityGuided entry, parachute descent, 8
rocket engine descent, sky crane 0.9
Aerojet Rocketdyne
MR-80B Hydrazine 3113 213 0.00851
SpaceX Falcon 9Grid fins to guide into atm, cold gas
thrusters to flip, 3 back boost engines 30.39 Merlin 1D
LOX/Kerose
ne 854000 311 0.47
Blue Origin New
Shepard
8 large drag brakes, hydraulically
actuated fins to steer, engines to
slow 34 BE-3 LOX/LH2 90000 N/A N/A
Space Shuttle 77 RS-25 LOX/LH2 1860000 366 3.17
134
Backup: Hand Calculations
135
Backup: Hand Calculations
136
Backup: Code
137
Backup: Code
138
Backup: Code
139
Backup: Code
140
Backup: References
[1] “EXTERNAL TANK,” NASA Available: https://science.ksc.nasa.gov/shuttle/technology/sts-newsref/et.html.
[2] “Shuttle technical facts,” ESA Available:
https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Space_Shuttle/Shuttle_technical_facts.
[3] “RS-25 Engine,” RS-25 Engine | Aerojet Rocketdyne Available: https://www.rocket.com/space/liquid-engines/rs-25-engine.
[4] “Propellant Tanks,” Purdue Engineering Available: engineering.purdue.edu › reportfinaluploads › appendix › structures
[5] Pietrobon, S. S.,“Analysis of Propellant Tank Masses,” NASA Available: https://www.nasa.gov/pdf/382034main_018%20-
%2020090706.05.Analysis_of_Propellant_Tank_Masses.pdf
[6] Greene W. D., “Space Shuttle Main Engine – Liquid Rocket Engines (J-2X, RS-25, general),” NASA Available:
https://blogs.nasa.gov/J2X/tag/space-shuttle-main-engine/.
141
Rachel RothFebruary 6, 2020
Backup Slides
Rachel Roth Backup Slides – Material PropertiesAl 7075-T7351 [5]
Rachel Roth Backup Slides – Calculations [4]
Rachel Roth Backup Slides – References[5] Aluminum Association, Inc. (2001). Aluminum 7075-T73; 7075-T735x. Retrieved from
http://asm.matweb.com/search/GetReference.asp?bassnum=MA7075T73.
[6] Federal Aviation Administration. (2003). Metallic Materials Properties Development and
Standardization (DOT/FAA/AR-MMPDS-01). Retrieved from http://everyspec.com/FAA/FAA-
General/DOT-FAA-AR-MMPDS-01-JAN2003_24102/.
[7] National Aeronautics and Space Administration. (2014). Structural Design Requirements and Factors
of Safety for Spaceflight Hardware (JSC 65828). Retrieved from
https://standards.nasa.gov/standard/jsc/jsc-65828.
[8] National Aeronautics and Space Administration. (2011). Standard Materials and Processes
Requirements for Spacecraft (NASA-STD-6016). Retrieved from
https://standards.nasa.gov/standard/nasa/nasa-std-6016.