1. Lunar Exploration Transportation System (LETS)
Baseline Design Presentation
1/31/08

2. Agenda Current CDD Summary Team Disciplines
Technical Description of Baseline Design
Assessment of Baseline Design using CDD
Recommended Changes to the CDD
Statement of Work (SOW) Summary

3. Team Disciplines CDD Team Technical Assessment Team
Eddie Kiessling
Technical Assessment Team
Nick Case and Matthew Isbell
Partnering Universities Team (SOW)
Seth Farrington

4. CDD Summary Level 1 Requirements Figures of Merit Surface Objectives
Concept Design Constraints

5. Level 1 Requirements Landed Mass TBD
1st mission landing site is polar region
Design must be capable of landing at other lunar locations
Minimize cost across design
Launch Date NLT September 30th 2012
Mobility is required to meet objectives
Survivability ≥ 1 year
Lander/Rover must survive conops.
The mission shall be capable of meeting both SMD and ESMD objectives.
The lander must land to a precision of ± 100m 3 sigma of the predicted location.
The lander must be capable of landing at a slope of 12 degrees (slope between highest elevated leg of landing gear and lowest elevated leg)
The lander shall be designed for g-loads during lunar landing not to exceed the worst case design loads for any other phase of the mission (launch to terminal descent). 5

6. Proposed FOMs Surface exploration
Maximized Payload Mass (% of total mass)
Objectives Validation: Ratio of SMD to ESMD: 2 to 1.
Conops: Efficiency of getting data in stakeholders hands vs. capability of mission.
Mass of Power System: % of total mass.
Ratio of off-the-shelf to new Development
Minimize cost 6

7. Surface Objectives Single site goals: Mobility goals:
Geologic context
Determine lighting conditions every 2 hours over the course of one year
Determine micrometeorite flux
Assess electrostatic dust levitation and its correlation with lighting conditions
Mobility goals:
Independent measurement of 15 samples in permanent dark and 5 samples in lighted terrain
Each sampling site must be separated by at least 500 m from every other site
Minimum: determine the composition, geotechnical properties and volatile content of the regolith
Value added: collect geologic context information for all or selected sites
Value added: determine the vertical variation in volatile content at one or more sites
Assume each sample site takes 1 earth day to acquire minimal data and generates 300 MB of data
Instrument package baselines:
Minimal volatile composition and geotechnical properties package, suitable for a penetrometer, surface-only, or down-bore package: 3 kg
Enhanced volatile species and elemental composition (e.g. GC-MS): add 5 kg
Enhanced geologic characterization (multispectral imager + remote sensing instrument such as Mini-TES or Raman): add 5 kg

8. Concept Design Constraints
Surviving Launch
EELV Interface (Atlas 401)
Mass
Volume
Power
Communications
Environments
Guaranteed launch window
Survive Cruise
Survive Environment
Radiation
Thermal
Micrometeoroids 8

9. Concept Design Constraints
Lunar Environment poles and equator)
Radiation
Micrometeoroid
Temperature
Dust
Lighting
Maximize use of OTS Technology (TRL 9)
Mission duration of 1 year
Surface Objectives
Reference: Dr. Cohen 9

10. Mars Viking Lander
First robotic lander to conduct scientific research on another planet
Dry Mass 576 kg
Science 91kg
Dimensions 3x2x2m
Power:
2 RTG
4 NiCd
Survivability:
-V1:6yrs 3mo
-V2:3yrs 7mo

11. Baseline Assessment Structures Thermal Systems
Payload and Communications
Power Systems
GN&C
Concept of Operations

12. Structures EELV Interface
Titan III which delivered the Viking lander is comparable to the Atlas V-401
The lander shall be designed for g-loads during lunar landing not to exceed the worst case design loads for any other phase of the mission (launch to terminal descent).
Comparable G-load launch spikes
The lander must be capable of landing at a slope of 12 degrees (slope between highest elevated leg of landing gear and lowest elevated leg)
Landing platform designs for Viking could also apply to LETS design

13. Structures
Lunar Environment (Radiation, Micrometeoroid, Temperature, Dust)
Thermal cycles vary greatly
Viking thermal cycles were approx. max 17°F, min -170°F
LETS can expect a thermal cycle approx. max 373 K, min 126 K,
Resistance to dust abrasion
Viking used a silicon paint to protect the surfaces from Martian dust
LETS could use a similar product
Landed Mass (TBD)
Viking required a bio-shield and a aero-decelerator
LETS will not require these items
Viking structural frame used lightweight aluminum
LETS could benefit from major advances made in materials

14. Thermal Systems Viking Thermal System Passive Geometry
Internal thermally controlled compartment
Structurally integrated thermal sinks
Increased or Decreased Surface Area where applicable
Thermal Coatings
Proper infrared emittance
Proper solar absorbance
Thermal Compartment
Critical equipment will be housed in compartment
Temperature will be dependent upon operating temperatures of critical equipment
Insulation
Thermal control between equipment and environment
Radiation shield
Active
Heaters
Continuous operation
Thermostatically controlled
Redundant systems

15. Thermal Systems LETS Thermal System Different Thermal Cycles
Heaters and Insulation changes to accommodate different thermal cycles
Statically charged lunar dust increases the absorptance of radiator surfaces
Use of polarized surfaces/coatings to reduce lunar dust accumulation

16. Payload and Mobility Scientific Options
Measure 15 samples in the dark and 5 samples in light.
The Viking Lander did not move, but it used an SSRA with a boom, collector head, and shroud unit, capable of collecting a variety of material elements.
Each sampling site separated by 500 m.
The Viking Lander did not have this capability.
Determine composition, geotechnical properties, and volatile content of regolith.
The Viking Lander used an X-ray Fluorescent Spectrometer (XRFS) to perform a chemical analysis.
Enhanced geological characterization (multi-spectral imager & remote sensing instrument).
The XRFS plus a remote sensing instrument may be used for this function.

17. Observation Camera Options Viking Lander camera system
Looked at surface and was able to measure optical density of the atmosphere
Geologically characterize the surface
Look for macroscopic evidence of life
LETS camera system
Observe electrostatic dust on the horizon
Study change in lighting conditions and the effects of surrounding environment
Aid in Earth observation and control of data collection

18. Communication Transmission options Direct transmission used by Viking
Relay from Viking Orbiter to Earth
UHF linked used to transmit data at speeds of 4000 and 16000bps
Transmission Criteria for LETS
=> 1 Earth day to transmit data
Limit of no slower than 4000bps
Transmission Path Options
Direct transmission from the Moon to Earth
Storage of data until DLS is obtained
Lunar orbiter to relay data to earth

19. GN&C
The lander must land to a precision of ± 100m 3 sigma of the predicted location.
Viking: Orbiter/Lander separation until the Lander was on the Martian surface
The propulsion system along with a navigation system consisting of radars, gyros, accelerometers, etc to guide the Lander through Mars atmosphere and a soft accurate landing on the Martian surface.
GN&C was not responsible for any operations after landing
LETS: Operations will commence upon landing, and will continue for the duration of the mission.
The lander must be capable of landing at a slope of 12 degrees
GN&C in conjunction with structure will ensure that the Lander can function on a 12 degree slope.
Mobility is required to meet objectives
GN&C will be responsible for rover and SSR deployment.

20. Power Systems Operational Period Power Required Systems
Viking Mars Lander was 90 days
LETS will be 365 days
Power Required Systems
Viking Lander
Telemetry
Communication
Thermal systems
Instrumentation
Ascent and descent operations
Caution and warning systems
Power conditioning
Regulate power
Power storage
LETS will be required to supply power to similar systems

21. Power Systems
Power Supply Options
Solar Cell
Battery
RTG

22. Power Systems Radioisotope Thermoelectric Generator (RTG)
Nuclear Yield:
Fuel: Plutonium – 238
Nominal Heat Generation Rate:
682 Watts
Weight & Dimensions:
15.4 Kg (34 lbm)
53 cm x 41 cm (23 in x 16 in)
Power Output:
35 to 780 Watts

23. Power Systems Advantages Disadvantages ASRG/SRG (Nuclear)
Constant Power Supply
Thermal Output can be utilized for thermal systems
Requires Fewer Batteries
Solar Panels
Minimize Cost
High Power to Weight Ratio
Clean Energy
Politically Safe
Disadvantages
ASRG/SRG (Nuclear)
Political Affairs
Nuclear Waste
Hazardous / Contamination
Expensive
Solar Panels
Degrade Over Time
Non-constant Power Supply
No Thermal Output
Susceptible to Lunar Environmental Conditions
Requires Many Batteries

24. Concept of Operations

25. Concept of Operations

26. SOW Committee
Statement of Work for Partners
Software
Communications

27. Statement of Work ESTACA Southern University (SU)
Sample Return Vehicle
Southern University (SU)
Mobility Concepts

28. SOW Committee Software Protocols Professional Documents
Computer Aided Design (CAD)
Unigraphics NX as standard for UAH and Southern University
CATIA as standard for ESTACA
CAD Translation Options
TransMagic
MathdataHQ.com
Professional Documents
MS Office
Text Documents – MS Word
Spread Sheets – MS Excel
Slide Presentation – MS Power Point

29. SOW Committee Communication Protocols File Sharing Protocols Meetings
One meeting per week required
Minutes will be required
UAH and ESTACA
Teleconference, or a web-based video chat
UAH and Southern University
Video conference, teleconference, or web-based video chat
Note: Minute template will be provided
File Sharing Protocols
WebCT – Primary
Basic - Secondary

30. IPT Schedule Spring 2008 Schedules Activity UAH Southern University
Classes Start
January 7
January 8
MLK Holiday
January 21
Mardi Gras Holiday
January 4-5
Founders Day
March 10
Spring Break
March 17-23
March 17-24
Last Day of Classes
April 22
April 25

31. CDD Recommendations
No Recommended Changes

32. Questions?