Payload Design Criteria for the Space Test Program Standard Interface Vehicle (STP-SIV)

1. Payload Design Criteria for the Space Test Program Standard Interface Vehicle (STP-SIV) Mr. Mike Marlow STP-SIV Program Manager National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

2. Purpose • Mission Capabilities Of The STP-SIV Spacecraft • Standard Spacecraft To Payload Interfaces • Top-level Detail To Determine If STP-SIV Is A Candidate For Your Mission National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

3. 2005 2007 2009 2011 2013 SERB Payload Analysis Concept Definition Requirements Definition Industry Briefings Source Selection Documentation Source Selection SIV Delivery Order #1 (STPSat-2) Payload, LV Determination S/C and S/V Development & Test 1 Apr 06 DO#2 (STPSat-3) DO#3 (STPSat-4) DO#4 (STPSat-5) 1 Apr 12 DO# 2 buy long leads at ATP DO# 3 long leads on shelf DO#4 S/C Pre-assembled Last Order Date STP-SIV Road Map National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

4. +Z +X +Y Spacecraft Capability Orbit Altitude 400 – 850 km Orbit Inclination 0° – 98.8° Launch Mass ≤ 180 kg (ESPA driven) SV Stored Volume (cm) 60.9 x 71.1 x 96.5 (ESPA driven) Reliability (at 7 months) 0.90 Stabilization Method 3-axis Pointing Modes Nadir, Sun Pointing, Safe Attitude Knowledge 0.03° 3σ (goal 0.02° 3σ) Attitude Control 0.1° 3σ (goal 0.03° 3σ) Bus Voltage 28 V ±6 Comm Frequency SGLS Command Rate 2 kbps uplink Telemetry Rate 2 Mbps downlink Data Storage 8 Gbits Payload Volume 0.14m3 Payload Mass 60 kg National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

5. Launch Vehicle Compatibility Pegasus/Raptor Falcon 1 EELV Secondary Payload Adaptor (ESPA) [Atlas and Delta] Minotaur I Minotaur IV National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

6. Sample Payload Configurations Payload Volume Payload Interface Panel Star tracker Silver Teflon Coated Radiator Rigid LV Interface Panel Y X Z Spacecraft Design 2 fixed/deployed arrays 1 gimbaled array GaAs UTJ solar cells 30 A-hr Li Ion battery 1 Star Tracker, 1 magnetometer 6 sun sensors, 1 GPS receiver, 3 reaction wheels, 3 torque rods National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

7. Topside Sounder Concept on STP-SIV • Configuration above shows four deployed 4-m antennas on all four corners of the STP-SIV spacecraft • This effectively yields two, crossed 8-m dipole antennas National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

8. Spacecraft to Payload Interfaces Mechanical • 1” grid aluminum panel • #10 fasteners • Stringent environment Thermal • Coupled Heat Transfer • Plate temperatures: -20o to +50o C • 100 Watts Heat Rejection Power Data • 100 Watts Orbit Average • 28 V ±6 • Up to 2 Mbps data rate • RS-422 Command and Telemetry • Synchronous data transmission • 8 Bi-Level Discreet I/O channels • 8 analog channels/payload EMI • Case by Case • System Test • on each mission National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

9. Feasibility Study • Payload to spacecraft compatibility • Payload to payload compatibility • Identifies potential risks • ROM estimate to integrate, test and operate National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

10. Opportunities • Enables space weather communities to leverage S&T spaceflight opportunities • Share SIV payload space • Rideshare S&T launch opportunities • ESPA on every EELV, payload adaptors on Minotaurs I & IV • Provides cost-effective platform to demo payloads and systems to support space weather programs • Basis for follow-on programs • Larger spacecraft class • Use of spacecraft to payload “standard” interfaces National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

11. Summary • SIV is a change from past STP business practices • Moving away from “one-of-a-kind” spacecraft to gain benefits of successive spacecraft builds • More responsive IDIQ contract, fits with other Space Development & Test Wing IDIQs • Planned to provide improved access to space for SERB S&T payloads • Potential benefits for broader space community National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

12. Payload Design Criteria for the Space Test Program Standard Interface Vehicle (STP-SIV) Mr. Mike Marlow STP-SIV Program Manager National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

13. Spacecraft Payload 1 M T P D Payload 2 Standard Payload to Spacecraft Interfaces • Power • Supply primary main electrical power to payload • Supply redundant main payload power • Supply power for payload heaters • Data • Supply bilevel discrete signal from spacecraft to payload for reset or other switching functions • Provide command data from spacecraft to payload • Provide data transfer from spacecraft to payload (code upload, time synch, attitude, GPS) • Provide digital telemetry data from payload to spacecraft • Provide analog data from payload to spacecraft (state of health monitoring) • Mechanical • Fasten payload hardware to spacecraft structure • Align payload hardware to spacecraftreference • Thermal • Sense temperature at payload to spacecraft interface • Control temperature at payload to spacecraft interface by affecting spacecraft side National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research

14. Jan 06 Oct 05 Apr 06 Oct 08 Apr 08 Oct 10 STP Rideshare Opportunities FY06 FY07 FY08 FY09 FY10 FY11 FY12 FY13 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q 1Q 2Q 3Q 4Q FY09 Minotaur IV There are potentially 30 ESPA-class spacecraft rideshare opportunities between FY09 – FY13 PL Selection Development Mission Integr Launch DMSP F-19 SPL Selection Special Studies* Mission Unique Mission Integr Launch STP-2 SPL Selection Special Studies* Mission Unique Mission Integr Launch FY11 Minotaur PL Selection Mission Integr Launch DMSP F-20 SPL Selection Special Studies* Mission Unique Mission Integr Launch FY13 Minotaur PL Selection Mission Integr Launch National Science Foundation Workshop on Small Satellite Missions for Space Weather and Atmospheric Research