1. AGGIELOOP
Final Design Presentation
Presented by:
Tadeo Huerta, Craig Medlin, Morgan O’Neil, Tyler Paschal, and Nathan Stephens
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2. Introduction
Needs Statement
“Provide a design for a reusable capsule that will safely, reliably, and comfortably transport up to 30 passengers
through a low pressure tube up to – and down from – high speeds with minimal losses due to drag and friction. This
system will provide maximum passenger throughput with minimal downtime between departures.”
About Our Pod
• Aggieloop-001 “Basilisk”
• Semi-monocoque aluminum construction with a carbon fiber outer skin
• Air bearing levitation system
• Transports payloads at relatively high speeds efficiently and safely
What makes us unique?
• Proven Industry Components
• Battery Cooling System
• Flexible Design
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3. Aerodynamics & Structures
Shell
• CFRP
• Profile optimized using CFD
• Structural support, aerodynamic
efficiency, and light weight
Structure
• 6061-T6 Aluminum
• Semi-monocoque construction
• MATLAB optimization
• Structural support of a solid body,
light weight, conforms to shell
Ducting
• Sheet steel
• Housing for fan/compressor at full scale
• Reduces air pressure at nose
• Added diffuser for increase in fan/compressor performance
CFRP Shell
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4. Aerodynamics & Structures
6061-T6 Aluminum Semi-
monocoque (Preliminary)
Shell
• CFRP
• Profile optimized using CFD
• Structural support, aerodynamic
efficiency, and light weight
Structure
• 6061-T6 Aluminum
• Semi-monocoque construction
• MATLAB optimization
• Structural support of a solid body,
light weight, conforms to shell
Ducting
• Sheet steel
• Housing for fan/compressor at full scale
• Reduces air pressure at nose
• Added diffuser for increase in fan/compressor performance
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5. Aerodynamics & Structures
Air Bypass Ducting
Shell
• CFRP
• Profile optimized using CFD
• Structural support, aerodynamic
efficiency, and light weight
Structure
• 6061-T6 Aluminum
• Semi-monocoque construction
• MATLAB optimization
• Structural support of a solid body,
light weight, conforms to shell
Ducting
• Sheet steel
• Housing for fan/compressor at full scale
• Reduces air pressure at nose
• Added diffuser for increase in fan/compressor performance
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6. • Acceleration
– Pod pusher for acceleration to test
speeds
• Air Bearings
– Near Frictionless interface with
tube
– No need for thrust
– Allows for longest time at test
speed without providing thrust
Levitation
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Pusher Interface and Compressed Air Tanks

7. • Acceleration
– Pod pusher for acceleration to test
speeds
• Air Bearings
– Near Frictionless interface with
tube
– No need for thrust
– Allows for longest time at test
speed without providing thrust
Levitation
Isometric view of Sled
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8. Levitation
AIRFLOAT Air Skids:
• Optimized for smooth surfaces
• Varied and frequent use in industry
• Low air tank capacity and airflow
requirement
• Utilizes pressurized air
• Vertical self-regulation
12” Air skids (AIRFLOAT)
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9. Horizontal Stability wheels
• Guides the pod along the rail
• Keeps in constant contact with the rail
• Is dampened to avoid other parts of pod coming
into contact with the rail
• Springs only exert minimal pressure on the rail
Stability
Front view of wheels on rail
Isometric view of wheels on rail
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10. High capacity wheels
• Solid
• Deployable
• Powered by a 5 HP AC Motor
Disc Brakes
• Adjustable brakes for constant braking
• High friction on concrete on the outside of the
aluminum track
Taxiing and Braking
Notional Wheel and Brake design
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Axle Brakes
• Backup for Disk Brakes
Deployment
• Spring and diaphragm pneumatic actuators
that raise when filled with air
• Use of two solenoids to fill and dump
diaphragm provides redundancy

11. Controls
• Control Unit
– Single Board Computer
– Embedded Linux
• CAN Bus
– Reliable
– Industry Proven
• “End Node” Module provides
universal interface
• SpaceX Network
– Telemetry
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“End Node” Board Designed by Aggieloop

12. Controls
• Safe-Stop
– In case of any of the following:
• Tube anomaly
• Excessive vibration
• Excessive acceleration
• Loss of air bearing
pressure
• Operator input
– Stop command will be issued
• Deploy wheels, apply
brakes at full power
• If brakes fail, engage
emergency brake
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Conceptual GUI
Mockup

13. Sensor Locations
13Potential Exterior Sensor Locations

14. Sensor Locations
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Notional Battery Temperature Sensor Location

15. Sensor Locations
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Prototypical Internal Sensor Locations

16. Energy
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Li-Po Battery Selection
• High energy density
• Ease of overall maintenance
• Fewer cells than Lithium-Ion
• Hard-case pack filled with
fire-safe material

17. Energy
High Voltage Module
• Main source of power
• 4 modules on board
Module Specifications
● 60 VDC
● 285 Ah
● 2.5 kWh
● 55 cells
Pack Integration
● Four modules wired in series
● Provides enough power to run all
components through testing
procedures, and during the actual run
● Refrigeration system to operate in
vacuum pressure to cool batteries
Module of 55 batteries
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18. Energy
12 V Battery
12V Module
Specifications
● 12 VDC
● 15 Ah
● 180 kWh
Pack Integration
• Redundant power supply for the control systems
• Location isolated from the main battery bank
• Enough power to activate the pod stop command
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19. Cooling
Purpose
• Provides cooling for high energy batteries
• Operates in vacuum pressures
• Utilizes air from air bearings for cooling medium
Plate Heat Exchanger
• Efficient cooling in low volume device
• Thin plates optimize surface area
• Multiple plates maximizes volume flow
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Plate Heat Exchanger

20. Cabin
Payload
• Simulated weight of 8 people and life support systems for small scale
• Can simulate this weight with experimental equipment
– Have the capability of running pod with pressurized, or low pressure
equipment on board
Life Support
• Air conditioning, CO2 scrubber, backup air supply
• Backup lights
– Battery powered, and glow strips for redundancy
• Added door for access to cabin to place sensors, ballast, and experimental
equipment
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21. Cabin
Cabin External RenderingCabin Cross Section
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22. Conclusion
Aggieloop-001 "Basilisk"
– Cost: $40,000
– Length: 16’
– Weight: 2500 pounds
– Structurally sound
– Flexible design
– Aerodynamically efficient
– Sufficient power supply
– On-board experimentation
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Why We Are Here
• To pursue our passion
• Make a contribution
• Change the world

23. 23
Special Thanks

24. Flow Optimization
Solidworks CFD simulations
– Simulated pod in tube, with air flowing around
– Low drag at 0.02 psi in tube (~1.5 lb)
– Internal (ducting) and external simulations
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External Flow Simulation Internal Flow Simulation

25. MATLAB Optimization
Method
• Dependent variables: Stresses on
structure
• Independent Variables: Member
cross sectional area; Components in
pod
• Control Variables: Quantity of
structural members
• Grid based optimization of all
combinations of members
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Approach
• Utilizes solid mechanics principles
for structural analysis
• Purpose: Optimize quantity of
structural members used in semi-
monocoque

26. Levitation
Air Bearing Cross Sectional View Diagram
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27. Levitation Comparison
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Air Bearings (Air
Float)
Magnetic Levitation
(Arx-Pax)
Lift Capacity (per pair) 6,000 lb 243 lb
Cost (per pair) $2,250 $10,000
Power Consumption
(W)
Minimal (Power draw
from regulators)
4400
Number of Pairs 2 11
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28. Secondary Movement
• Suspension
– Inspired by motorsport
• Pushrod actuated suspension mounted on linear
actuators
• Motor for taxiing
– 5hp AC motor
• Cheaper than equivalent DC motor
• Lighter than equivalent DC motor
– Connected to wheels via CV axles
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29. Wheels
• Pistons use air pressure to raise the wheels
–In case of pressure loss wheels will automatically deploy with
assistance from springs
• Wheels will be retracted once the air bearings take the load of the pod
• There will be a pair of solenoids on each line to the pistons
–Controls the airflow to the pistons, allows for fault tolerance
• Once the wheels are deployed the brakes will engage
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30. Controls
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Controller System Network Flow Chart

31. Sensors
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•High tech laser-retroreflective
sensor
•Contains laser of class 2
•30 micro-second response time
•Sensing range is 10 meters
•Retro-reflectivity will keep track of
the pod’s position
•Remaining pod length can be
calculated
•Location is top front of the pod
DK_LAS-54/76/110/124 Contrast Sensor GP2Y0E02A Orientation Sensor
•Measures distance using a
CMOS image sensor and IR-LED
•Depending on detected distance
it will output a corresponding
voltage
•Location will be along side each
exterior corner of the pod
•All four sensor’s data must be
equal to ensure correct orientation
else breaks will be deployed
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32. Sensors
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BMA280 Accelerators
•2mm X 2mm
•Triaxial
•Low-g acceleration sensor
•Contains digital interfaces
•Ability to sense tilt, motion, and
shock
•Location on bottom of
passenger compartment
BME280 Pressure/Temperature/Humidity
•High linearity
•High accuracy
•Long term stability
•Absolute barometric
pressure sensor-
exceptionally high accuracy
•Measures ambient
temperature at very low
noise and high resolution
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33. Sensors
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ADXRS453 Attitude Sensor
•Complete rate gyroscope
•300 degree per second angular rate
sensing
•Ultrahigh vibration rejection
•Internal temperature compensation
•SPI Digital output with 16-bit data word
•Consistently checks for angular rotation
of the pod
•If out of range motion detected the
wheels will be deployed
LDT0-028K Vibration Sensor
•Contains Polymer film
•Screen-printed electrodes
•Two crimped contracts
•High voltage generated if film is
displaced from neutral axis
•Vital component of pod’s stability
detection
•Reports stable/unstable state
•Location includes forward and
backward interior of the pod
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34. Energy
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Power Consumption vs Battery Capacity

35. Energy
Wiring Schematic
High Voltage Pack
Specifications
● 240 VDC
● 285 Ah
● 10 kWh
● 220 cells
Battery Control Module
● Balances charging/discharging of cells
Electrical Distribution System
● Transmits energy to Pod components
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36. Cabin Figures
• Seat Pitch
– 48 in
• Seat Width
– 22 in
• Ceiling Height
– 66 in
• Estimated Full Scale Mass
– Carry on per person – 18 lbs
– Seats – 15 lbs each
– People 120 lbs (5th percentile) – 220 lbs (95th percentile)
– Estimated mass of life support systems – 750 lbs
– Small scale estimated total mass – 870 lbs
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• Cabin Pressure - 11.34 pisa
• Cabin Temp - 72 F
• Cabin Humidity Level - 0.12%
• Partial pressure CO2 after journey - 0.11 psia
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37. Full Scale Cabin Safety
• Fire
– 3m Novec 1230 fire protection fluid
• Nontoxic to the environment
• Faster than CO2
• Air
– Emergency Air Required
• 10.57 lbs (21 % O2, 79% N2/H)
• Stored in composite pressure vessels
– Loss of Cabin pressure
• 10.17 psi (Stable Cabin pressure: 11.4 psi)
• Drop down masks
– High CO2 content
• Flood Style air replacement
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• Emergency Door Opening Procedure
– Analog Gauge Displays pressure difference
between the cabin and the tube
• In case of total power loss
• Easily readable
– Mechanical system only allows door to open when
there is a safe pressure differential
• Emergency Lighting
– Battery powered in case of total power loss
– Afterglow phosphor based material
• 30 hours of luminescence
• Incase battery lights are out
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38. Full Scale Safety
• Total power loss
– Backup battery ensures the on board computer can still bring the pod to a controlled stop.
• Atmosphere introduction in tube
– Pod will naturally begin to slow down due to higher air pressure. T
– he on board computer will then bring the pod to a controlled stop
• Pod becomes stuck in tube
– Reintroduce atmosphere to the tube, enter the tube
– Determine if pod can be moved out of tube under its own power
– Remove pod from tube
• Redundant systems
– Redundant power supply
– Redundant systems for deploying the wheels
– Redundant life support systems
– Redundant systems for slowing down the pod
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