Comparison of Reentry Breakup Measurements for Three Atmospheric Reentries€¦ · Comparison of...
18
1 © The Aerospace Corporation 2013 Comparison of Reentry Breakup Measurements for Three Atmospheric Reentries Andrew S. Feistel Michael A. Weaver William H. Ailor Vehicle Systems Division The Aerospace Corporation 6 th IAASS Conference: Safety is Not an Option May 2013
Transcript of Comparison of Reentry Breakup Measurements for Three Atmospheric Reentries€¦ · Comparison of...
1© The Aerospace Corporation 2013
Comparison of Reentry Breakup Measurements
for Three Atmospheric Reentries
Andrew S. Feistel
Michael A. Weaver
William H. Ailor
Vehicle Systems Division
The Aerospace Corporation
6th IAASS Conference: Safety is Not an Option
May 2013
2
The Aerospace Corporation
Overview
• Introduction
– Space Debris
– Motivation for Reentry Recordings
– Overview of Reentry Breakup Recorder (REBR)
• Host Vehicle Details
• REBR Data Transmissions
• REBR Flight Data Comparisons
– Flight Profiles
– Labeling of Events
– Sensor Suite Data
– Summary
• Future Development
– Next Generation of REBRs
– Technology Transition
3
The Aerospace Corporation
Thailand, 2005
• Space hardware reenters at very
shallow angle (<1 degree)
• ~50 objects weighing more than 1 ton
reenter randomly per year
• Major breakup at ~78 km or lower
• Debris spreads over long, narrow
footprint (~2,000 x 70 km)
• 10 to 40% of dry mass on orbit
survives to the Earth’s surface,
posing potential hazard to people and
property Illustration not to scale
South Africa, 2000
By Die Burger/Johann van Tonder
Saudi Arabia, 2001
NASA
Texas, 1997
NASA
Mongolia, 2010
By Nandia Bandorj,
Mongol News Media Group
Oklahoma, 1997
By Brandi Stafford, Tulsa World
Introductionto Reentry Debris
Brazil, 2008
Argentina, 2004 Uruguay, 2011
USAFLa Nacion Line Staff
NASAUOL News Staff
4
The Aerospace Corporation
IntroductionMotivation for Obtaining Data from Reentry Breakup
• Program end-of-life disposal decisions require accurate knowledge of hazards posed by surviving debris
– Disposal decision can lead to shorter mission life, increased cost, higher risk
• Different models giving different results
– Debate in the reentry community as to which results are correct
• Data lacking on how unprotected vehicle following shallow reentry trajectory responds to heating environment
– Observational data provides macroscopic view (basis for assumed breakup altitude in several models)
• Need to collect detailed, real-time data during reentry to predict incipient conditions that lead to demise
– Data can be used for
• Direct comparisons with predictions
• Improved physics modeling for reentry survivability
• “Design for demise” with well validated survivability models to minimize future reentry risks
5
The Aerospace Corporation
• Physical design
– Small: 8.6 kg, 36 cm diameter, 28 cm high (installed)
– Self-contained, autonomous, survivable, locatable
– Solid state sensor suite and data recorder
• 3-axis low-g accelerations (± 1.7 mg range)
• 3-axis high-g accelerations (± 120 g range)
• 3-axis rotation rates
• Internal pressure and temperatures
• Heat shield thermocouples
– Internal GPS to provide real-time location
– Light-weight, rugged heat shield to protect electronics and data from severe environments
– Satellite modem to send data to ground station
• Mission profile
– Attached to host vehicle, sleeps until reentry
– Wakes up and records data through breakup
– Transmits data during fall via Iridium satellite system
– Hardware retrieval not required
IntroductionReentry Breakup Recorder (REBR)
6
The Aerospace Corporation
Host Vehicle DetailsGeneral Information
• All host vehicles have been ISS resupply spacecraft of roughly the same physical shape
– Cylindrical with ~10 meter length and ~4.5 meter diameter
ATV-2, photo courtesy NASA
HTV2, photo courtesy NASA
• H-II Transfer Vehicle (HTV)
– Japan Aerospace Exploration Agency
– Launch mass of ~20,000 kg
– Solar panels conformal with main body
• Automated Transfer Vehicle (ATV)
– European Space Agency
– Launch mass of ~15,000 kg
– Solar panels span 22.3 m
7
The Aerospace Corporation
Host Vehicle DetailsFor Specific REBR Flights
Host Vehicle HTV2 ATV-2 HTV3 ATV-3
Reentry date 30 Mar 2011 21 Jun 2011 14 Sep 2012 3 Oct 2012
Vehicle attitude at reentry Controlled Tumbling Controlled Tumbling
Flight path angle at 120 km (deg) -1.229 -1.655 -1.426 -1.663
Velocity at 120 km (km/s) 7.591 7.580 7.605 7.593
REBR name REBR1 REBR2 REBR3 REBR4
REBR mass (kg) 4.44 3.95 4.17 4.09
REBR mounting system soft hard soft soft
REBR successful? yes no yes yes
8
The Aerospace Corporation
-51.772
-51.765
-51.758
-51.751
-51.744
-51.737
-51.73
-51.723
-118.08 -118.02 -117.96 -117.9 -117.84
La
titu
de (
de
cim
al d
eg
)
Longitude (decimal deg)
REBR Data Transmissionsand Water Impact Survival Notes
• REBR not designed for either survival or demise upon
water impact
– Concept is to transmit major-breakup data
before water impact
– Survivability is not a requirement
• Two of the three successful flights continued to
transmit after water impact
REBR1 REBR3 REBR4
Sensor suite data transmitted before splash (sec) 256 500 386
Real-time transmission duration before splash (sec) 372 362 263
Survived splash? yes yes no
Sensor suite data transmitted after splash (sec) 0 194 0
Real-time transmission duration after splash (hr) 16.9 10.0* 0
REBR1 lat/long
post-impact
*REBR3 transmitted for 139 seconds immediately after impact, then went
silent for 23.1 hours, then reconnected to Iridium and transmitted for 10 hours.
The sensor suite data buffer was corrupted after the transmission hiatus.
9
The Aerospace Corporation
REBR Data TransmissionsExample Interpretation of Early Events – REBR4
• Line 1 (0 sec, 94.9 km)—REBR begins recording: Rotation rate present at beginning of REBR data due to intentional ATV-3 spin
• Line 2 (79 sec, 78.7 km)—REBR internal pressure begins to decrease. Breach of pressure containment in ATV-3
• Line 3 (98 sec, 74.9 km)—Bump in accelerometer data, beginning of more pronounced motion. Possible ATV-3 debris shedding?
• Line 4 (103.9 sec, 73.7 km)—Large bump in low-g, high-g accelerometer and gyro data. Initiation of main structural breakup of ATV-3? REBR Housing released, bouncing around inside ATV-3?
• Line 5 (125 sec, 69.4 km)—Large bump in accelerometer data. REBR Housing strikes another object?
• Line 6 (133 sec, 67.8 km)—Pronounced movement in both gyro and accelerometer data. REBR Housing exposed to airstream?
• Line 7 (139.25 sec, 66.5 km)—Both gyro and accelerometer data go erratic. First rise in REBR heat shield temp. REBR released from housing.
10
The Aerospace Corporation
REBR Flight Data ComparisonFlight Profiles (Best-Estimate)
0
10
20
30
40
50
60
70
80
90
100
0400800120016002000
Alt
itu
de
(k
m)
Range (km)
REBR1
REBR3
REBR4
0
10
20
30
40
50
60
70
80
90
100
0612182430
Alt
itu
de
(k
m)
Mach Number
REBR1
REBR3
REBR4
0
10
20
30
40
50
60
70
80
90
100
-90-72-54-36-180
Alt
itu
de
(k
m)
Flight Path Angle (deg)
REBR1
REBR3
REBR4
11
The Aerospace Corporation
REBR Flight Data ComparisonAltitude and Best Estimate Trajectory (BET) Acceleration as Seconds Past 120 km Entry Interface (EI)
0
1
2
3
4
5
6
7
8
9
10
0
10
20
30
40
50
60
70
80
90
100
110
120
0 100 200 300 400 500 600 700 800 900
Ac
ce
lera
tio
n (
g, fr
om
BE
T)
Alt
itu
de
(k
m)
Time (seconds past EI)
REBR1REBR3REBR4
12
The Aerospace Corporation
0
10
20
30
40
50
60
70
80
90
100
01503004506007509001050120013501500165018001950
Alt
itu
de
(k
m)
Range (km)
REBR1REBR3REBR4
REBR Flight Data ComparisonEvent Labeling
Initial REBR
Pressure Drops
Start Main
Structural BreakupREBR Clear of
Breakup Events
Data Transfer
Initiated
REBR First
Data Point
13
The Aerospace Corporation
0
10
20
30
40
50
60
70
80
90
100
0 2 4 6 8 10 12A
ltit
ud
e (
km
)
Acceleration (g)
REBR4
0
10
20
30
40
50
60
70
80
90
100
0 2 4 6 8 10 12
Alt
itu
de
(k
m)
Acceleration (g)
REBR3
0
10
20
30
40
50
60
70
80
90
100
0 2 4 6 8 10 12
Alt
itu
de
(k
m)
Acceleration (g)
REBR1
REBR Flight Data Comparison
REBR1 (HTV2) REBR3 (HTV3) REBR4 (ATV-3)
Data Transfer Initiated
Data Transfer Initiated
Data Transfer Initiated
Modem On
Modem On
Modem On
Pressure Drop
Pressure Drop
Pressure Drop
Main Breakup/REBR Release
33 sec durationMain Breakup/REBR Release
33 sec duration
Main Breakup/REBR Release
35 sec duration
14
The Aerospace Corporation
REBR Flight Data Comparison
Other REBR data available but not shown here: internal temperatures and voltages
Internal Pressure Heat Shield Temp. RSS of Gyro Rates
0
10
20
30
40
50
60
70
80
90
100
0 20 40 60 80 100
Alt
itu
de
(k
m)
Pressure (kPa)
REBR1REBR3REBR4
0
10
20
30
40
50
60
70
80
90
100
0 0.2 0.4 0.6 0.8 1
Alt
itu
de
(k
m)
Temperature (normalized)
REBR1REBR3REBR4
0
10
20
30
40
50
60
70
80
90
100
0 120 240 360 480 600
Alt
itu
de
(k
m)
Gyro RSS (deg/s)
REBR1REBR3REBR4
15
The Aerospace Corporation
Event
REBR1
(HTV2)
REBR3
(HTV3)
REBR4
(ATV-3)
REBR start of data recording 90.1 91.7 94.9
REBR pressure drop 79.2 83.6 78.7
Initial debris shedding 75.4 77.9 74.9
Start of main structural breakup 70.5 72.1 73.7
REBR gyros/accels go erratic 67.1 67 67.8
Rise in REBR heat shield temp. 65.5 65.3 66.5
REBR clears breakup event 64.7 64 64.8
Peak REBR heat shield temp. 55.9 46.9 53.6
REBR modem on 53.2 48.1 36.2
REBR reaches subsonic speed 31.0 29.2 31.6
Start of data transfer 29.3 25 12.7
SummaryTable of Events by Altitude (km)
16
The Aerospace Corporation
SummaryREBR Preliminary Findings and Lessons Learned
Qualifiers
• Data for deorbited vehicles of similar design; two aft-end forward during reentry
(HTV2, HTV3), one tumbling (ATV-3)
• Breakup assessments based on data from REBR’s internal sensors only (no data on
what’s happening at other points in reentering body)
Assessments
• REBR core vehicle will survive reentry breakup
• All three reentries to date had
– Significant reentry breakup events between 74-64 km altitude
– REBR devices departed from the host vehicles between 68-66 km altitude
– REBR completely clear and in stable flight between 65-64 km altitude
• Data enables top-level assessment of reentry breakup predictions
• Data from REBR internal sensors alone insufficient for comparison with detailed
breakup models
17
The Aerospace Corporation
Future DevelopmentMotivation and Concept for REBR-Wireless (REBR-W)
Wireless Sensors:
Host Vehicle
REBR-W
• Current REBR design records data from internal sensors
• Ultimate goal: Collect data from distributed sites around the host vehicle
– Temperature, heat flux data would enable direct comparison with
predictions from existing reentry survivability models used for
reentry risk assessment
– Pressure, strain, other data would provide indications of breakup
sequence and have additional use for future applications and
modeling needs
• Wired connections to distributed sensors around the host vehicle pose
significant operational and integration issues
• REBR-W combines REBR system with remotely located wireless sensors
– Remote sensors placed strategically around host vehicle on
components of interest
– Remote sensors wirelessly communicate with a transceiver unit
attached to REBR housing
– Transceiver communicates with REBR through wired connection
utilizing current heat shield penetration paths
• REBR-W architecture and temperature data collection have been
successfully demonstrated in lab testing
• Funding is currently being sought for the fabrication of flight systems to
meet already available upcoming flight opportunities
18
The Aerospace Corporation
• Aerospace entered into exclusive licensing agreement for REBR technology and underlying
patent with Terminal Velocity Aerospace (TVA), LLC
• TVA offers a variety of REDs (ReEntry Devices), directed at markets in reentry debris safety
and utilization of space
– Currently available:
• RED-Data, based on REBR, to collect and return reentry breakup data
– Future products:
• RED-Test, for space and reentry flight testing of materials and technologies
• RED-Treasure, for space flight and return of small personal items
• RED-SafeReturn , for black-box and structural-health monitoring data for reusable
vehicles
• RED-Sensor, based on REBR-W, wireless collection of reentry breakup data
• Aerospace maintains cooperative relationship with TVA for ongoing research and
development related to REBR technology and applications
• TVA will make a good-faith effort to share collected data with Aerospace, subject to approval
from the host-vehicle owner, for use in serving the national interest
Future DevelopmentTechnology Transfer
