IBEX Concept Study Site Visit

1
IBEX Project and Flight System Overview IBEX
Science Working Team Meeting June 15,
2005 Presented by Susan Pope Southwest
Research InstituteSan Antonio, Texas
2
Recent History

• GSFC Explorers office Kickoff and Debrief on Feb
  18, 2005
• Major and minor strengths in all areas
• 7 minor weaknesses (1 payload)
• 1 major weakness (rocketry)
• SwRI contract signed May 18, 2005.
• May 18 start date and June 15, 2008 launch date
  provides 5-months schedule margin.
• All subcontractors have been turned on with full
  funding.

3
Mission Schedule
4
Near Term Review Dates

• System Requirements Review Sept. 7-8, 2005
• Payload Preliminary Design Review Dec. 12-13,
  2005
• Mission PDR Jan. 17-18, 2005
• Confirmation Assessment Review Jan. 19, 2005
• Confirmation Readiness Review Jan. 30, 2006
• Confirmation Review Feb. 13, 2006
• Begin Phase C/D Feb. 16, 2006
• Payload CDR June 7-8, 2006
• Mission CDR July 26-27, 2006

5
IBEX Org Chart
6
Launch Configuration
7
Launch Movie
Movie courtesy of Orbital Sciences Corporation
8
Launch Operations

• S/C power positive after launch
• Spin axis within 60º of Sun line
• S/C coasts up to apogee
• Apogee burn by S/C hydrazine subsystem
• 66 minute burn raises perigee to 7000 km

9
Mission Design

• Nominal orbit 37 Re x 7000 km altitude, 5 days
  per orbit
• Sun-pointing spinning S/C (4 rpm)
• Science Observations gt 10 Re
• Engineering lt 10 Re
• Data download and command upload
• Adjust spin axis 5 (Earths orbital motion)
• Nearly full sky viewing each 6 months

10
Spacecraft Bus Configuration

• Central thrust-tube core structure
• Components on 6 side panels
• Top deck mounted solar array

• Major-axis spinner
• Two spherical outboard fuel tanks
• Two axial and 4 lateral thrusters

11
Solid Rocket Motor

• Toroidal igniter with dual flamesticks
• 3-D carbon-carbon throat
• Star 30 Carbon phenolic exit cone

• Welded 27-inch dia titanium alloy case
• Silica-filled EPDM rubber insulation
• Head-end-web (HEW) propellant grain

12
Rocketry Trade Tree
ACS Sensors
Lateral Thruster Size (Qty 4)
Active Nutation Control Use
Pre-SRM Burn
During SRM Burn
After SRM Burn
Accels Only
1 Newton thrust
NO YES
NO YES
NO YES
MEMs Gyros Only
5 Newton thrust
Accels MEMS Gyros
Propellant Tank PMD Selection
None (spin expulsion only) Elastomeric
diaphragm Metallic diaphragm Sponge (surface
tension) Start-up basket (surface
tension) Start-up trap (hydro-static) Gas bubble
suppressor Vortex suppressor TBD combination of
the above
Aft Deck Thruster
Propellant Tank Selection
Existing
No aft deck thruster
1 aft deck thruster (5N)
Modified
New
1 aft deck thruster (22 N)
Apogee Raise Method
By SRM alone
Most done by SRM, Rest done by HPS
13
Payload Block Diagram
14
IBEX-Lo Subsystems
TOF (Cluster/CODIF)
Collimator (Phase A Prototype)
ENA? Ion Conversion (IMAGE/LENA)
Ion ESA (Polar/TIMAS)
15
IBEX-Hi Subsystems
Collimator (Phase A Prototype)
ENA ? Ion Conversion (IMAGE/MENA)
Coincidence Subsystem
Standard ESA
16
Combined Electronics Unit
12.5
6.5
3.75

• Primary Functions
• Accept 5V, 14V, and 15 V from SCB
• Distribute LV power to both sensors
• Provide 8 HV outputs to IBEX-Hi
• Provide 7 HV outputs to IBEX-Lo
• Store all telemetry (Science, H/K and S/C)

17
Payload Cross-Calibration
IBEX S/C Mockup
IBEX-Hi
IBEX-Lo
CEU
SwRI Ion/Electron Calibration Facility
IBEX Payload Mounted in Cal Facility
18
Integration of IBEX Payload
IBEX-Lo
CEU
IBEX-Hi
19
IBEX Ground Segment
IBEX ScienceOperations Center(ISOC) (SwRI)
Antenna Sites (USN)
Mission Control Center (MCC) (Orbital)