tether boostfacilitiesjun01
TRANSCRIPT
Tether Boost Facilities forIn-Space Transportation
Robert P. Hoyt, Robert L. ForwardTethers Unlimited, Inc.
1917 NE 143rd St., Seattle, WA 98125-3236+1-206-306-0400 fax -0537
[email protected] www.tethers.com
John Grant, Mike Bangham, Brian TillotsonThe Boeing Company
5301 Bolsa Ave., Huntington Beach, CA 92647-2099(714) 372-5391
TUI/MMOSTT 2
NIAC Funded Tether Research
¥ Moon & Mars Orbiting Spinning Tether Transport (MMOSTT)
¥ Hypersonic Airplane Space Tether Orbital Launch (HASTOL)
¥ Objectives:Ð Perform Technical & Economic Analysis of Tether Transport SystemsÐ Identify Technology NeedsÐ Develop Conceptual Design SolutionsÐ Prepare for Technology Development Efforts and Flight Experiments
to Demonstrate Tether Transport Technology
TUI/MMOSTT 3
Momentum-ExchangeTether Boost Facility
¥ High-strength tether rotates around orbiting control station
¥ Tether picks payload up from lower orbit and tosses payload into higher orbit
¥ Tether facility gives some of its orbital momentum & energy to payload
¥ Tether facility orbit must be restored to enable it to toss additional payloads
TUI/MMOSTT 4
Electrodynamic Reboost
Magnetic Field
CurrentThrust
Plasma Contactors(Hollow Cathode,FEA, Bare Wire)
¥ Power supply drives currentalong tether
¥ Plasma contactors exchangecurrent with ionosphere
¥ Plasma waves close currentÒloopÓ
¥ Current ÒpushesÓ againstgeomagnetic field via JxBForce
TUI/MMOSTT 5
Momentum-Exchange/Electrodynamic-Reboost Tethers:
Summary of Advantages
¥ Tether Boost Facilities Can Provide a Fully-Reusable In-SpacePropulsion ArchitectureÐ LEO ⇔⇔⇔⇔ MEO/GTO
Ð LEO ⇔⇔⇔⇔ Lunar Surface
Ð LEO ⇔⇔⇔⇔ Mars
Ð ETO Launch, in combination with Hypersonic Airplane/RLV
¥ Momentum Exchange + Electrodynamic Tether Can EnablePropellantless Propulsion Beyond LEO
¥ Rapid Transfer TimesÐ 5 days to Moon
Ð 90-130 days to Mars
¥ Operational Tether System Can Be Tested Before Use With High-Value Payloads
¥ Reusable Infrastructure + Low Consumables ⇒⇒⇒⇒ Lower Cost
TUI/MMOSTT 6
¥ Developed Orbital Architecture for Round Trip LEO⇔⇔⇔⇔LunarSurface Transport
¥ Whole System Launch Mass = 30x Payload MassÐ LEO Tether Boost Facility Mass = 13x Payload Mass, Lunar Tether Facility = 17x Payload
¥ 13 Payloads/Year
¥ Incremental Commercial Development Path
Cislunar Tether Transport System
TUI/MMOSTT 7
Rapid Earth-Mars Transport
Payload pick-up
Payload release OriginEscapetrajectory
Interplanetarytrajectory
DestinationInboundtrajectory
Payload release
Payload capture
Patch point
Tapered tether
Loaded TetherCenter of massorbit
Tapered tether
Loaded TetherCenter of massorbit
Patch point
Earth’s gravitationalsphere of influence
Mars’ gravitationalsphere of influence
Sol
INTERPLANETARY TRANSPORT USING ROTATING TETHERS
¥ Reusable Architecture for Round Trip Earth to Mars Transport
¥ Rapid Transfer Times (90-130 days)
TUI/MMOSTT 8
MXER Tethers Included in NASAÕsIISTP Process
¥ NIAC Funded MMOSTT and HASTOL efforts have resulted inMomentum-Exchange/Electrodynamic Reboost Tethers beingconsidered in NASAÕs In-Space Integrated Space TransportationPlanning Process
¥ TUI & NASA/MSFC developed concept designs for Tether BoostFacilities for 4 classes of missionsÐ Microsatellite
Ð 1 mt Payloads
Ð 5 mt Payloads
Ð 10 mt Payloads
¥ IISTP Process evaluated these designs in trade studies for severaldifferent scientific missions
¥ ÒHigh-Risk/High PayoffÓ
¥ MXER Tethers scored well for several classes of missionsÐ High Performance metric
TUI/MMOSTT 9
Tether Architecture forLEO-GTO-LTO-Mars Transport
¥ Tether facility serves as transport hub for multiple destinations
¥ Tether serves as a zero-propellant, reusable, high-Isp, high thrustÒThird StageÓ
TUI/MMOSTT 10
5mt Payload Tether Boost Facilityfor In-Space Transportation Architecture
¥ Reusable In-Space TransportationInfrastructure
¥ Payload Launched to 325 km LEO
¥ Tether Boosts Payload to Elliptical Orbit
¥ Tether Uses Electrodynamic Thrust to Reboost
Tether System Point Design:
¥ Boost 10,000 kg to GTO
¥ Boost 5,000 kg Vehicle to :Ð Highly Elliptical Orbit (C3=-1.9)
Ð Lunar Transfer Trajectory
Ð Escape Via Lunar Swingby
¥ Tether Facility Launch Mass: 63 mtÐ Deploy using 3 Delta-IV-H LVÕs
Ð Retain Delta Upper Stages for Ballast
Ð 200 kW EOL Power Supply for 1 Month Reboost
Analysis of Other Propulsion Technologies withMX Tether Assist:
¥ Delta-II-Class LV Launches 5,000 kg Spacecraft
¥ Tether Boosts Spacecraft to C3Ê=Ê-1.9 km2/s2
¥ High-Thrust Propulsion Systems:Ð Do Injection Burn at Perigee (570 km, 10.62 km/s)
¥ Low-Thrust Propulsion Systems:Ð Use Lunar Swingby to Escape EarthÕs Gravity Well
TUI/MMOSTT 11
Net Payoff: Reduced Launch Costs
To launch 5,000 kg to GTO:
¥ Using Rockets: Delta IVM+(4,2) or SeaLaunch
~ $90M
¥ Using Rocket to LEO, Tether Boost to GTO:
Ð Delta II 7920 (~$45M) or Dnepr 1 (~$13M)
Ø1/2 to 1/7 the launch cost
TUI/MMOSTT 12
LEOððððGTO Boost Facility
¥ Initial Facility Sized to Boost 2500 kg Payloads to GTO
¥ First Operational Capability Can Be Launched on 1 Delta IV-H
¥ Modular Design Enables Capability to be Increased
¥ Top Level Mission Requirements:
99%Payload pickup reliability
15 daysOperational orbit lifetime
100% of tracked spacecraftCollision avoidance
10 years +Mission life
30 daysTurnaround time
< Delta IV/Ariane 5Payload environment
< Delta IV/Ariane 5Release insertion error
GTORelease orbit
300 km equatorialPickup orbit
2500 kg at IOC, can grow to followmarket
Payload Mass
ValueRequirement
TUI/MMOSTT 13
Mass Properties Breakdown
1330.01000.01000.033%11Tether reeling assembly
330.001330.01000.0Tether Deploy & Control
0.540.50.58%11Beacon
0.040.540.5Docking & I/C Subsys
489.9326.6163.350%21PMAD/PCUt
113.590.845.425%21Plasma Contactor (FEAC)
186.0603.4417.4ED Tether Power Subsys
12.9213.8200.9ADCS
7.86.93.513%21transponder
0.97.86.9TT&C
29.426.013.013%21Computer
3.429.426.0C&DH
1.61.40.713%21Transceiver
0.510.50.213%12Comm. antennae
0.22.11.8TFS Net Comm Subsys
0.510.50.213%12Downlink antennae
1.561.40.713%21Downlink Transceiver
0.22.11.8Downlink Comm Subsys
51.345.422.713%21PMAD
54.248.03.013%28PV array drive motors
3289.52860.52860.515%11Power Storage
2014.61782.91782.913%11PV array panels
673.05409.64736.7Electr.Pwr.
680.33401.32721.125%Structure
247.4997.0749.633%Cabling/Harnesses
165.71270.11104.515%1Thermal Control Subsys
23001326710967LEO Control Station
MassMargin
(kg)
Mass withContingency
(kg)
Mass withno margin
(kg)
Unitmass(kg)
MassContingency
Redundancy
QtyControl StationMass: 10,967 kg
Tether Mass:
8,274 kg
Grapple Mass:
650 kg
GLOW: 19,891 kgÐ 15% margin w/in Delta
IV-H payload capacity
Expended Upper Stage
3,467 kg
On-Orbit Mass:
23,358 kg
TUI/MMOSTT 14
Tether Boost Facility
Control Station¥ Solar Arrays, 137 kW @ BOL¥ Battery/Flywheel Power Storage¥ Command & Control¥ Tether Deployer¥ Thermal Management
Tether (not shown to scale)
¥ Hoytether for Survivability¥ Spectra 2000¥ 75-100 km Long¥ Conducting Portion for
Electrodynamic Thrusting
Grapple Assembly¥ Power, Guidance¥ Grapple Mechanism¥ Small Tether Deployer
Payload AccommodationAssembly (PAA)¥ Maneuvering & Rendezvous Capability¥ Payload Apogee Kick Capability
Payload
Total Mass:ÊÊÊÊ 23,358 kgPayload Mass: 2,500 kg
TUI/MMOSTT 15
NIAC Efforts Have DevelopedImproved Tether Analysis Tools
Tether System Design:Ð Tapered tether design
¥ Spectra 2000
Ð Orbital mechanics considerations todetermine facility mass required
Tether operation: TetherSimª
¥ Numerical Models for:Ð Orbital mechanics
Ð Tether dynamics
Ð Electrodynamics
Ð Hollow Cathode & FEACs
Ð Geomagnetic Field (IGRF)
Ð Plasma Density (IRI)
Ð Neutral Density (MSIS Ô90)
Ð Thermal and aero drag models
Ð Endmass Dynamics
Ð Payload Capture/Release
¥ Interface to MatLab/Satellite Tool Kit
TUI/MMOSTT 16
LEOððððGTO Boost Facility
¥ TetherSimª Numerical Simulation (10x real speed)Ð Tether Dynamics, Orbital Mechanics
TUI/MMOSTT 17
Technology Readiness Level
¥ Boeing & TUI Performed TRL Analysis of MXER TetherTechnologies
¥ Many necessary components are already at high TRL
¥ TRL Analysis Indicates Areas for Future Work to Address:Ð Power management subsystem
Ð Thermal control subsystem
¥ Higher power than previously flown systems
Ð Electrodynamic Propulsion Subsystem
¥ Plasma contactors
¥ Dynamics control
Ð Automated Rendezvous & Capture technologies
¥ Prediction & Guidance
¥ Grapple Assembly & Payload Adapter
Ð Some work ongoing in HASTOL Ph II effort
Ð Flight Control Software
Ð Traffic Control/Collision Avoidance
TUI/MMOSTT 18
0
4
8
12
ÆZ
(m
)
16
20
-10 0 10ÆX (m)
Rendezvous
¥ Rapid AR&C Capability Needed¥ Relative Motion is Mostly in Local Vertical¥ Tether Deployment Can Extend Rendezvous
Window
¥ Additional Tether Deployment Under Braking Can Reduce ShockLoads
Payload Capture Vehicledescends towards Payload
PCV DeploysMore Tether PCV pays out tether
and Payload maneuversto dock with grapple
PCV engagestether brake and begins to lift payload
0
0.2
0.4
0.6
0.8
1
0 10 20
Lo
ad
Le
vel
30 40 50
0.1 s braking
5 s braking
10 s braking20 s braking
Time (s)
30 s braking
TUI/MMOSTT 19
Space Debris-Survivable Tether
¥ Micrometeoroids & Space Debris WillDamage Tethers
¥ Solution approach: spread tether materialout in an open net structure with multipleredundant load/current paths
PrimaryLines
SecondaryLines(initiallyunstressed)
0.2 to10's of meters
0.1- 1 meter
SeveredPrimary
Line
Effects ofDamageLocalized
SecondaryLinesTransfer Load Around Damaged Section
TUI/MMOSTT 20
Proposed RETRIEVE TetherExperiment
¥ Candidate SecondaryExperiment for XSS-11
¥ $800K in Initial Developmentfunds from AFRL
¥ Small ED tether system deorbitsµSat at end of missionÐ Activated only after primary
mission completed
¥ Mass: (CBE+Uncertainty): 6.5 kg
¥ DemonstrateÐ Controlled orbital maneuvering
with ED tether
Ð Long life tether
Ð Stabilization of tether dynamics
TUI/MMOSTT 21
µTORQUE: MX Tether to Boost µSat toLunar Transfer or Escape
Launch vehicleplaces primarypayload into GTO
¥ Microsatellite Tethered Orbit Raising QUalification Experiment
¥ Build Upon RETRIEVE to Create Low-Cost Demo of MXER tether technology
¥ Secondary payload on GEO Sat launch
¥ µTORQUE boost microsat payload to lunar transfer or escape
¥ 0.4 km/s boost to payload
¥ Mass-competitive with chemical rocket
µTORQUE deploys tether µsat above stage
µTORQUE uses EDdrag to spin up tether
µTORQUE releasespayload into lunartransfer/swingby
TUI/MMOSTT 22
µTORQUE on Delta IV
¥ Delta-IV Secondary Payload
¥ ~100 kg weight allocation
¥ Boost ~80kg microsat fromLEO to low-MEO
TUI/MMOSTT 23
Momentum Exchange/Electrodynamic ReboostTether Technology Roadmap
GRASPExperiment
µTORQUEExperiment
2001 2003 2005 201620132010 20352025
ProSEDS
µPET
ED-LEO Tug
LEO ⇔⇔⇔⇔ GTOTether Boost Facility
ISS-Reboost
TerminatorTetherª
Cislunar TetherTransport System
ETO-LaunchAssist Tether
RETRIEVE
NIAC Study
TUI/MMOSTT 24
Opportunities for NASATechnology Development
¥ Expand AR&C Capabilities for Rapid Capture
¥ High Power & High Voltage Space Systems
¥ Electrodynamic Tether Physics
¥ Debris & Traffic Control Issues
¥ Conduct Low-Cost Flight Demo of Momentum-Exchange Tether Boost
Modest NASA Investment in TechnologyDevelopment Will Enable Near-Term SpaceFlight Demonstration
TUI/MMOSTT 25
Contributors
¥ Boeing/RSS - John Grant, Jim Martin, Harv Willenberg
¥ Boeing/Seattle - Brian Tillotson
¥ Boeing/Huntsville - Mike Bangham, Beth Fleming, John Blumer,Ben Donohue, Ronnie Lajoie, Lee Huffman
¥ NASA/MSFC - Kirk Sorenson
¥ Gerald Nordley
¥ Chauncey Uphoff