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Project Overview
Why a Lunar Flying Vehicle (LFV)?
Through the Constellation Program, NASA plans to establish a permanent
lunar base near the south pole. This base will require the development of a transportation infrastructure for the efficient travel, research, and
exploration of the Moon’s surface.
An LFV can:
• Provide access to sites inaccessible with a rover (e.g. ,crater floors, mountain tops, rilles)
• Travel tens of kilometers in minutes as opposed to hours
• Utilize propellants available on site• Residual propellants from Altair lander (Liquid Oxygen (LOX), Liquid
Hydrogen (LH2))• In situ propellant production (ice or regolith)
• Launch rescue missions to recover a stranded rover crew
Lunar craters are objects of great scientific interest. Since craters are formed by impacts from bodies, such as meteoroids and comets, these
craters often contain deposits of materials that would not be normally
found in the lunar regolith. Of particular interest are deposits of hydrogen, which may indicate the presence of ice.
The graphic above depicts the planned
Constellation lunar outpost and nearby craters.
*Surface Architecture Reference Document (SARD). Ver. 3.4. 2008. p 13.
Alshain utilizes planned Constellation architecture without
modification for its delivery to the lunar surface.
Delivery Procedure:
• Arrives on cargo Altair mission in stowed configuration
(landing gear unattached)
• Unloaded from Altair using Tri-ATHLETE
• Lunar Surface Manipulator System (LSMS) suspends Alshain by its roll cage
• An EVA attaches the landing gear via bolt connections
• Alshain is fueled via in situ production facilities or by Altair’s residual propellant
Far Right: Image of an Altair lander with
attached Tri-ATHLETE for unloading cargo.
Right: LSMS crane unloading payload from
an Altair lander
Deployment
550680
1310
(1540 pulse)With 30% Margin
4205201010
(1180 pulse)Total Power
240--Life Support
77130Vehicle Lighting
202020Status Monitoring
255075Interface Box
50125125S/Ka Band Equipment
2550100Flight Computers
-3045IMU
505050WLAN
Equipment In Flight (W) Landed (W) 24-hour (W)
LIDAR 66 - -
Radar 10 - -
Star Tracker - 20 (10 min) -
Video Cameras 30 - -
Mass Data Storage 65 65 -
FPGAs/DSP 75 75 -
Propulsion Valves 170 (pulse) - -
Control Panels 50 50 -
(www.nasa.gov/pdf/203096main_TEC%20Splinter-Thermal%20control.pdf)
Main sources of heat flux:
• Solar radiation• Planetary reflection/radiation
• Power consumption• Astronauts
Onboard Alshian there are two 2 m2
optical solar reflectors (OSR) to account for
heat buildup in the avionics equipment and thermal louvers for heat loss during the
worst-case cold scenario. To protect the
astronauts, the seats are covered with white Aeroglaze A276 paint. There is also a layer
of multi-layered insulation (MLI) on each of the propellant tanks to control boil-off rates.
OSRhttp://www.qioptiqspace.com/Data/Images/space1.jpg
Thermal Louvershttp://www.nec.co.jp/aad/space/s3/image/image32.gif
Thermal System
Mechanical PR
Powered PR
RCS Valves
Main Engine Valves
RCS X 20
Pressure Tanks
LOX LOX LH2LH2
Main Engine
* All valves and non-mechanical pressure regulators are triply redundant
Fill Drain Valve
Power, Propulsion, and Thermal
Propulsion System
LOXLH2 Fuel Cell 1
Fuel Cell 2
LiFePo4
CFx
PMAD Powered Components
Propulsion system consists of:
• 4 He Pressure Tanks
• 2 LOX Tanks
• 3 LH2 Tanks
• 1 40 kN Main Engine
• 20 RCS Thrusters80 cm
100 cm
The RCS consists of:
• Eight 450 N thrusters in the xy plane
• Eight 1150 N thrusters in ± z direction
• Four 1150 N thrusters in - z direction
The power system uses two proton exchange member (PEM) fuel cells, a set of Lithium Ion Phosphate batteries, and a
set of Lithium/Carbon Monoflouride non-rechargeable batteries.
The power produced by these systems is managed by a power management and distribution (PMAD) unit, which distributes the
power amongst the avionics and other control systems. Power is provided for all the components listed in the power budget
below.
Power System
Hardware Ingress/Egress
Payload Elevator
Testing with a suited subject:
• Board vehicle and occupy the aft crew station• Manipulate control panels
• Occupy the forward crew station• Turn around and egress from vehicle
Incapacitated AstronautA dummy was constructed to mimic the weight distribution of an EVA suited 95th percentile American male in 1/6th Earth gravity for the purpose
of testing incapacitated astronaut rescue operations. The suited subject
was able to statically support the weight of the astronaut dummy for a period of ten seconds.
Elevator testing:
• Load elevator with mock payload
• Raise elevator to platform height
• Lower elevator to
ground
• Unload elevator
x
y
Parabolic Dishes
Propellant Tanks
Landing Gear
Pressurant Tanks
Cargo Elevator
FlightComputers
(4)
Sensors
Comm terminal rangingLRS rangingIMUStar TrackerLIDAR
Actuators
main enginesRCS
Antennas
HGA Crew Interface
Controls
HUD
Radar
LGA
Status
Four flight computers operate in parallel to ensure robustness to computer failures. These computers take
commands from the crew interface or the communications
system, process data from the navigational sensors, and issue the appropriate commands to the actuators.
acc/decelerating and pitchingacc/decelerating
coastingpropulsive glide
The vehicle follows a modified ballistic trajectory, transitioning into a propulsive glide for the final approach
and landing. Total time of flight for a 57km hop is 6
minutes.
Navigation
Initial position and attitude fixes are acquired via ranging to Lunar Relay
Satellites (LRS) and star trackers respectively. Inertial navigation allows
40 meter landing accuracy for a 57 km
hop.
Guidance Modes
• Autonomous: The flight computers manage all aspects of flight to bring the
vehicle to a preprogrammed target
location. A LIDAR scan is conducted for hazard avoidance.
• Direct Control: Automatic control loops maintain pilot-specified rates in
translation and rotation.
• Teleoperation: The vehicle flies
autonomously until the final approach, at which point the LIDAR scan is
transmitted to a remote pilot for landing point designation.
LRS LFVS-band
WLAN
Ka-band
Ka-band
WLAN
TDRSS
TDRSS
DSN
DSN
S-band
Ka-band
Outpost
S-band
MCC
High gain and omnidirectional systems are used on Ka and S bands to provide communication. Wireless LAN (WLAN) is used for short-range local applications. Omnidirectional S-band is used for voice, sensor, tracking, telemetry, and command data during flight. The high-gain parabolic dishes are used for high data rate applications such as video.
Link Budgets
Ka-band LRS
(26 GHz)
S-band LRS
(2.2 GHz)
Ka-band DTE
(26 GHz)
S-band DTE
(2.2 GHz)
Tx Gain 42 dB 2.0 dB 42 dB 2.0 dB
Tx Power 1.2 W 26 W 3.7 W 7 W
Rx Gain 46 dB 25 dB 77 dB 55 dB
Eb/No
required 9.4 dB 9.4 dB 13.5 dB 3.5 dB
Link margin of 6 dB for all communications modes.
Avionics
Nominal Flight Plan Guidance, Navigation, and Control
Communications
Alshain (Arabic for “falcon”) is a two-person lunar flying vehicle named for a
star in the same constellation as Altair.
• Range: 57 km each way (round trip)
240 km (one way)
• Inert mass: 1130 kg
• Propellant mass: 940 kg
• Crew survival reliability: 99.6%
• Estimated Cost: 1 billion dollars for
development and production of two
vehicles
Note: All dimensions are in meters Note: All dimensions are in meters
1.333.24
1.10
1.10
Project AlshainA Lunar Flying Vehicle for Rapid Universal
Surface Access
3.10
2.04
7.91
6.90
Loads, Structures, and Mechanisms
Support Base
The support base is comprised of six I-Beams and two pairs
of tubular crossbeams. The I-Beams allow for a low mass method of supporting the structure against moments and
other forces created during flight and landing. The support base sits just under the feet of the crew and is directly
connected to all of the major components.
The engine support is comprised of four tubular beams
connected to the support base. The engine must be
supported against its own weight during Earth launch and landing, as well as when it is fired on the Moon.
The tank support is comprised of thirty six tubular beams of
nine different sizes. The fuel tanks are empty during Earth launch, but on the Moon they must be supported with up to
400kg each. The pressurant tanks are full during Earth
launch, therefore their full weight must be supported at all times.
The landing gear are supported by copper beryllium torsional
springs at the support base and have copper beryllium linear springs along the footpads. Each leg is designed to support
the vehicle in a one leg landing scenario without tipping. The
landing gear is also equipped with two tubular side beams to support against twisting.
The roll cage consists of four curved tubular beams and six
straight tubular beams. The roll cage is designed to keep all critical components safe in the event of a roll over. A 30cm
buffer was included in order to provide protection from
surface hazards, while allowing for ingress/egress of the crew.
Engine Support Tank Support
Landing Gear Roll Cage
Outreach
Reference: http://www.aiaa-baltimore.org/photos/2009/PaperAirplaneChallenge
Volunteered as judges and assistants at the Baltimore Museum of Industry’s Maryland
Engineering Challenges.
• Paper Airplane Competition (Grades 1-5)
• Hovercraft Competition (Grades 6-8)• Cargo Airplane Competition (Grades 9-12)
Reference: http://www.aiaa-baltimore.org/photos/2009/PaperAirplaneChallenge
Crew Systems
Contingency Procedures•Accommodates two crew members in stadium seating
•Personal Life Support System
(PLSS) secures into latches on the PLSS Support Bars
• Astronauts’ boots are restrained at
the heel to prevent feet from kicking upward
• Restraint engagement confirmation
lights located on control panels
• Restraint release switches are located within easy reach of the crew
Lighting Control PanelsThe forward crew member is the nominal
pilot because of superior sight lines. The aft crew member is also provided a set of
controls for contingency operations
• 2 joysticks for manual control
• Physical warning lights
• Controller pad for mission critical controls
• Heads-Up Display (HUD)
• Voice commands in helmet
Four 20 watt halogen lamps illuminate:
• Crew flight control area
• Crew ingress/egress area• Cargo elevator
Four 50 watt halogen lamps illuminate the area surrounding the vehicle
24 Hour Life Support Requirements (per crew member)
•Breathing oxygen0.84 kg of O2 per day
•Carbon dioxide scrubbing1.00 kg of CO2 per day
•Cooling water re-supply5.22 kg of water for every 8 hours
15.7 kg replacement water needed for 24 hours
•Drinking water re-supply1.62 kg of drinking water per day
•120 W needed to power EVA suit
Project Alshain team members participated in University of Maryland
Engineering Open Houses:• Presented Alshain concept to prospective engineering students
• Answered questions about the engineering program and experiences at UMD
Roll Cage
Contingency Life Support Storage
Engine Accommodation
Control Panels
Seating and Restraints
The center of gravity envelope, pictured in green, displays the
worst case X and Z direction CG positions for the vehicle. The Y direction CG shift is negligible in comparison to the X and Z
shifts.
Center of Gravity Envelope
x
z
Amy Ross, Lunar Rover Vehicle Mockup Advanced Space Suit Ingress/Egress Test
Boot Platforms
PLSS Support BarsSeating Platforms
General Public
K-12Participated in the University of Maryland’s
annual Maryland Day:
• Presented Alshain concept and hardware• Lead tours of the Space System Lab’s
Minimal Functional Habitat Mock-up
• Assisted visitors with the use of the Space System Lab’s rover and shuttle computer
simulations
Campus198 hours, 100% participation
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