N S 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 550 680 1310 (1540 pulse) With 30% Margin 420 520 1010 (1180 pulse) Total Power 240 - - Life Support 7 7 130 Vehicle Lighting 20 20 20 Status Monitoring 25 50 75 Interface Box 50 125 125 S/Ka Band Equipment 25 50 100 Flight Computers - 30 45 IMU 50 50 50 WLAN 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 m 2 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. OSR http://www.qioptiqspace.com/Data/Images/space1.jpg Thermal Louvers http://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 LH2 LH2 Main Engine * All valves and non- mechanical pressure regulators are triply redundant Fill Drain Valve Power, Propulsion, and Thermal Propulsion System LOX LH2 Fuel Cell 1 Fuel Cell 2 LiFePo 4 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 Thrusters 80 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 Astronaut A dummy was constructed to mimic the weight distribution of an EVA suited 95 th percentile American male in 1/6 th 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
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Power, Propulsion, and ThermalPower, Propulsion, and Thermal Propulsion System LH2 LOX Fuel Cell 1 Fuel Cell 2 LiFePo 4 CFx PMAD Powered Components Propulsion system consists of: •
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N
S
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
* 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.