1. Bigelow Aerospace Genesis
Testing Expandable Spacecraft
in LEO
Tom Londrigan
Mission Operations Manager
Bigelow Aerospace
Used with Permission
2. Bigelow Aerospace Company Overview
Bigelow Aerospace is a privately owned company dedicated to
developing low-cost, next-generation crewed space
complexes.
Facilities and personnel
– Currently 95 personnel
• Seeking qualified engineers
– Main facility in North Las Vegas
• 500,000 Square foot assembly facility
• Fabrication capabilities for all modules
• Mission Control facility
• Ground communication assets
• Radiation exposure facility (LDRS) onsite
– Office in Washington D.C.
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3. Genesis
The Genesis program utilizes space vehicles in Low Earth Orbit
with the objective of testing and validating the technologies
necessary for the deployment of expandable space habitats
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4. Genesis
The Genesis program consists of two small scale prototype
spacecraft, currently in orbit
Genesis 1 – Launched July 12, 2006
Genesis 2 – Launched June 28, 2007
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5. Mission Profile
Orbital Parameters 583x556 km, 64.5 deg inclination
– Nominal 10 year mission orbital decay
Nominal Aft earth facing orientation
– Gravity gradient fallacy – more on this later
Insertion on Dnepr Launch Vehicle
– Silo launched
– SS-18 ICBM Modified for small satellite insertion
– Final Spacecraft integration occurred at Dombarovsky facility
Genesis launched inert, Auto activation on separation
No re-boost capability
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6. Mission Objectives
Primary Objective
– Demonstrate Inflation and Deployment in LEO
Secondary Objectives
– Develop core competency to build, launch and operate satellites and
space complexes
– Proof of concept for folding, restraint, and core structure
– Evaluate the Durability of soft goods
– Long term Effectiveness of the MMOD shield
Tertiary (Mission Creep) Objectives
– Revenue and interest-generating payloads
– Evaluate the performance of various off-the-shelf (literally) electronic
components
– Obtain long term evaluation of power systems
– Evaluate radiation environment
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7. Genesis Spacecraft description
Internal core structure, surrounded by inflated volume
– Battery and payloads in interior of spacecraft
– Some avionics contained on exterior of the core structure
– Launch adapter on aft end
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8. Genesis Spacecraft description
MMOD shield description
– Multi-layer insulation with interstitial foam to provide loft
– Restraint layer – load bearing
– Air Barrier
– Folded in launch configuration, restrained with straps
Deployment systems
– Retention straps released using pyro cutters
• Contingency - Retention straps sized to fail/release due to expansion
forces
– Solar array deployment
– All deployment and inflation controlled by onboard flight computer
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9. Genesis Payloads
Genebox - Genesis 1
– Small payload from Ames
– Objective was to test
sensors and optical
systems for GeneSat
Radiation Monitors
– Dose Depth Monitors
• RadFETs to measure
cumulative energy
deposition
– Proton Monitors
• Single Event Upset
measurement
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10. Genesis Payloads
Logos
– some demonstration,
some paying customers
“Fly-Your-Stuff” program
– Small objects and cards
– Allow private individuals to
fly small objects in space
verified by downlinked
photos
– Approximately 80
customers
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11. Genesis Systems
Inflation
– Genesis 1 : Single tank, redundant solenoid valves
– Genesis 2 : 4 tanks, 1 solenoid valve each
Power
– 8 Solar array “wings”, single battery with redundant charge
regulators
– Solar array capacity was intentionally over-designed, with partial
capability available even in deployment failure.
– Solar arrays were designed to be tolerant of solar incident angle
Communications
– Redundant omni-directional antennae on each end of spacecraft
– UHF/VHF for duplex command and telemetry
– S-band for photo downlink
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12. Genesis Systems
Telemetry
– Genesis 1 – 1172 data parameters
– Genesis 2 – 1830 data parameters
– All data is recorded onboard the spacecraft and downloaded as
encrypted files during passes over ground sites
– Data sampling rate can be scaled up and down as necessary to
prevent build up of data
– Real time data points can be obtained by direct query while in
communication coverage
– Data is collected and archived at the Las Vegas site
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13. Genesis Systems
Cameras
– Genesis 1: 18 cameras for internal
and external evaluation of softgoods,
some oriented on payloads
– Genesis 2 : 22 cameras for internal
and external evaluation of softgoods
• Mounted on solar arrays (4) for
observing softgoods and capturing
projector images
• Interior Pan-Tilt-Zoom cameras
operable from ground
• Wireless deployable camera on
exterior of MMOD shielding
• Some oriented on internal payloads
• Fisheye and Narrow field of view
mounted on ends
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15. Genesis Systems
Projectors
– Off the shelf from the local electronics store, modified only enough to
allow remote commanding and mounting
– Placed on aft and forward solar array ends to project images onto
exterior
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16. Attitude Control Systems
Mission Design provided very forgiving pointing requirements
– Nadir aft orientation and rotation about long axis provided a benign
thermal environment – ‘rotisserie’ effect
– RF link margin and antenna radiating patterns allowed for comm.
from almost all angles
Hardware
– Magnetometers
• 2 mounted in forward end
– Sun Sensors
• 4 on forward structure
– Magnetic torque rods
• 2 mounted in X (longitudinal) axis
• One each mounted in Y, Z axes
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17. Ground Station Network
Description of Ground communications architecture
– For Genesis 1 launch, VA and NV ground stations only
– UHF, VHF uplink capability
– 6-meter S-band dish
– Some leased sites, however all assets are the property of Bigelow
Aerospace
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18. Ground Stations
Setup and commissioning of new ground stations
– For Genesis 2 launch added AK, HI sites
– Shifted VA ground station to Maine and added S-band dish
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20. De-Orbit
De-orbit Analysis
– Current orbital lifetime is estimated to be 12 years
• We are examining the drag models and refining estimates on a monthly
basis
– Object Reentry Satellite Analysis Tool (ORSAT) de-orbit analysis from
April 2004
• Parent body and Fragmentation analysis
• All structural components predicted to demise upon re-entry
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21. Spacecraft Construction and Testing
Spacecraft assembly occurred at Nevada facility, followed by shipment to
Russia.
Final checkout at launch base, then turned over to Kosmotras for integration
onto the space head module
– ITAR at the time necessitated stringent restrictions for launch base ops and
plans for recovery of possible launch failure.
Applying design updates in an accelerated design cycle between Genesis 1
and 2
– Integration begun less than six months after launch of Genesis 1 - 6 months
before scheduled ship date
Limitations of Facilities and equipment on testing
– Most equipment bench tested but bare bones approach prevents a large
amount of testing systems for end to end testing
– Difficulties in fully testing ACS sensors, radio systems in flight configuration
Risk tradeoffs/ Risk acceptance
– Ultimately for Genesis 1 and 2, there was just one paying internal customer,
who was willing to evaluate and accept risks
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22. Overview of Genesis 1 and 2 operations
Creating Mission Operations from scratch – all prior efforts had
been on building the spacecraft
– Creating plans – as basic as establishing chain of command for
decision making
– Establishing procedures where there are none
• flight rules – discuss prior to eliminate real-time debate, Etc.
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23. Genesis Operations
First contact – planning for contingences on an experimental
spacecraft
– Minimal ground assets in place, spacecraft tumbling which
complicated contact
• Effectively, contact time was 2-3 minutes
– Needed to perform quick health and status evaluations
– Downlink photos to satisfy THE customer
– Verify all functions of automated sequence
– Nominal tipoff rate of insertion was <2 RPM – we got better than this
but ACS system was not fully operational – no stability for the first
week
Follow-on operations
– We are holding pressure – pictures are pretty, now what?
– Examining the inflation sequence and increasing pressure
– Downloading complete data sets, all photo documentation
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24. Results
Both Spacecraft have performed flawlessly on primary objective
– inflation and deployment
Power Consumption
– battery performance was within design tolerances
– No appreciable solar array degradation in capacity
Inflation results – stable pressure with no leakage
Thermal – Genesis provided data and analysis of the soft goods
performance in an orbital environment
Communications – this mission provided spaceflight heritage for
radios which are planned to fly on future missions
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25. Lessons Learned from Genesis 1
In God we trust, all others bring data – rapid build process had
not captured test data
– If it is not documented, it did not happen
ACS – not all disturbance torques were captured in first analysis
– Rapid integration of the algorithm resulted in constant on of torquers
• ACS system had to be reconfigured on orbit
– Initial ‘gravity gradient’ fallacy – other disturbance torques proved
dominant
Identified need for baseline testing and documentation –
compressed schedule did not allow for validation of as built
configuration
Thermal sensors were few, and sensor placement needed
better documentation
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26. Applications to Genesis 2
Implemented test plans
Established Pre-ship review process
Increased thermal sensors and thoroughly documented
placement on spacecraft
– Placed thermal sensors within the MMOD shielding
– Modeled the sensor placement with CAD programs
Documented all test data for comparison
on orbit
– Mission Operator input was used to create new formats and
cataloguing of data
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27. Genesis 2 Initial Ops
What we improved
Operations
– Established and validated procedures on Genesis 1
– Validated all Genesis 2 procedure delta’s during testing
– Better communication plans
– Baseline testing allowed better system performance evaluation
– ACS system algorithms debugged
• Checklist for activation rather than turning it on
• When we turned the ACS system on, communications stabilized within
48 hours
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28. Lesson Learned from Genesis 2
Mission Data Analysis – empirical data for LEO
– Thermal Data
– Radiation Data
– Drag Analysis – performing model comparisons, essential for future
vehicles
• Continuing ongoing analysis shows some unexpected data not fully
modeled
– Example: eccentricity of orbit fluctuating – counter-intuitive to the drag
model
• Long term effort using Two Line Element and tracking data to evaluate
orbital lifetime
Identified the need for a high fidelity ground analog vehicle for
testing
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29. Obstacles to Overcome
Limitations on ground station access – all operations become
time critical
ITAR restrictions
Minimizing expenditure on ground infrastructure while using
only proprietary assets
Genesis systems were simple but most lessons learned were
procedural – problems will be prevented
Maintain highly creative, innovative atmosphere while creating
more rigorous processes
No acceptance criteria (at first)
Overcome ‘Not invented here’ mentality
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30. Applications to future spacecraft
Future vehicles
– Sundancer
• Crewed module
• Engineering proof of concept
• Approximately 180 m3
– BA Standard
• Full size module ~300 m3
• Capable of 3 crew
– Propulsion Bus
• Attached node for complex assembly
• Reboost and resupply capability
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