FORMOSAT-3/COSMIC Mission Satellite Performance: Five Years in Orbit

Transcription

1 5th FORMOSAT-3 / COSMIC Data Users Workshop and International Conference on GPS Radio Occultation, Taipei, Taiwan, 13~15 April 2011 FORMOSAT-3/COSMIC Mission Satellite Performance: Five Years in Orbit Chen-Joe Fong, Eddy Yang, and Nick Yen National Space Organization (NSPO)

2 Spacecraft Configuration Solar Array Drive Battery GOX POD1 Antenna Filter Solar Array S-band Transmitter & Receiver Battery Charge Regulator (BCR) Tri-Band Beacon (TBB) Electronics GOX Occultation Antenna (OCC1 ANT) TIP Electronics Tiny Ionospheric Photometer (TIP) POD1 RF1 ANT0 OCC1 RF4 ANT3 SADA Wheel Battery GOX POD2 RF2 ANT1 OCC2 RF3 ANT2 Solar Array Torque rod Reaction Wheel GOX POD2 Antenna Flight Computer (FC - upper) Attitude Control Elec. (ACE - middle) GPS Receiver (bottom) GPS Occultation Experiment (GOX) GOX OCC2 Antenna Mission Interface Unit (MIU - upper)/ Power Control Module (PCM - bottom) Earth Horizon Sensor (EHS) Fuel Tank TBB Antenna S-band Antenna 2

3 Spacecraft State of Health Summary SC Spacecraft State Operational Mode Subsystems ACS EPS C&DH GOX TIP & TBB FM1 Battery Degradation Fixed- Yaw High Rate Operating 95% Off 1 FM2 Power Shortage Fixed- Yaw High Rate Operating 73% Off 1 FM3 SAD Abnormal Phoenix Since 7/6/ Off 1 Off 1 FM4 Battery Degradation Fixed- Yaw High Rate Operating 64% Off 1 FM5 Battery Degradation Fixed- Yaw High Rate OCC1 Not Stable 75% Off 1 FM6 Battery Degradation Fixed- Yaw High Rate OCC1 Not Operating 95% Off 1 Note 1: Secondary Payloads are power-off due to power shortage 3

4 FORMSAT-3 Satellite Constellation FM5 FM2 FM6 FM4 FM1 750 FM3 A ltitu d e (k m ) /15/06 7/24/06 11/1/06 2/9/07 5/20/07 8/28/07 12/6/07 Date FM5 -> FM2 -> FM6 -> FM4 -> FM3 -> FM1 FM6 Orbit Raise Up due to Leak 4

5 FORMOSAT-3 / COSMIC Radio Occultation Profiles Atmospheric Total 2,560,930 since launch (as is of ) The highest Atmospheric RO numbers is 2514 on 2008/9/23 Ionospheric Total 2,643,249 since launch The highest ionospheric RO numbers is 3213 on 2007/3/4 FM1 FM2 FM3 FM4 FM5 FM6 Total Atmosphere 516, , , , , ,487 2,560,930 Ionosphere 457, , , , , ,952 2,643,249 Atmospheres: FM4 > FM1 > FM5 > FM6 > FM2 > FM3 Ionosphere: FM4 > FM1 > FM2 > FM6 > FM5 > FM3

6 Major Spacecraft Anomaly Summary System & MO Lost of Communication on FM2/3/6 Stay in Phoenix Mode on FM2 PCM DC Off on FM2 Bus GPSR Non-Fixed Anomaly Issues C&DH Computers Resets/Reboots on All FMs ACS CSS Sun Vector Estimate Incident EHS Sensor Offset Test Burn Failure SC Unstable After Calibration Burn FSW Hmlog Increasing on FM5/ TCS EHS#2 High Temperature RCS Orbit Raise Up on FM6 (2010/1/15 & 2010/3/21) Pressure transducers malfunction on FM2/3/5/6. EPS Solar Array Drive Lockout on FM3 Power Shortage Anomaly on FM2 BCR dmdc Charge Anomaly on FM2/3/5/6 Battery Over Pressure on FM2 -> FSW 6.2 PL Unexpected Off on FM1/3/4/5/6 Battery Degradation -> FM1/4//5/6 Phoenix Mode on FM3 since 7/6/2010, GOX GOX RF1 (POD1/ANT0) SNR Anomaly on FM1/3/4/5/6 GOX RF4 (OCC1/Ant03) SNR Anomaly on FM3/5/6 GOX SNR Decreasing at Higher Temperature on FM6 GOX Reboot Loop on FM1/2/3/5/6 Science Data Drop-out out Issue TBB TBB/GOX Interference Issue on FM2, 4, 5 TIP TIP Instrument Initialization Issues TIP Twilight On/Off Issue 6

7 FORMOSAT-3 / COSMIC Radio Occultation Profiles (as is of ) Atmospheric Ionospheric FM6 FM5 FM4 FM3 FM2 FM1 7

8 Satellite Performance - GOX Payload TIP & TBB payloads are power off due to power shortage POD1 Antenna Signal-to-Noise Ratio Issue on FM1, FM5, & FM6 POD2 Antenna Signal-to-Noise Ratio Issue on FM5. OCC1 Antenna Signal-to-Noise Ratio Issue on FM5 and FM6 FM5 POD1 Ant SNR FM6 OCC2 Ant SNR R 500 N S R 500 N S /04/ /04/ /04/ /04/ /04/ /04/ /04/ /04/ /04/ /04/ /04/ /04/15

9 Satellite Performance - Electrical Power Subsystem (EPS) - FM3 Battery has lost regularity, capacity, charge functions FM5 s charge and regularity functions still work according to Battery voltage and SOC data Except FM3 and FM5, Battery have no extraordinary errors FM3 SOC with trending 25 Batt SOC Batt SOC HHT Residual 16 FM5 Battery Voltage Min Batt Volt Batt Volt HHT Residual C a p a c ity (Ah ) Voltage[V] Date Day 10.3

10 Five Years Payload Off Events Statistics (2006/4/15~2011/3/1) FM4 -> FM5 -> FM6 -> FM1 -> FM2 -> FM FM1 SOC FM2 SOC FM3 SOC FM4 SOC FM5 SOC FM6 SOC /4/ /4/ /4/ /4/ /4/ /4/19

11 Satellite Performance - Attitude Control Subsystem (ACS) - Attitude performance has been performing as expected, no degradation has been observed. Attitude sensors and actuators are OK Wheel friction index indicates no wheel degradation. GPS receiver status: FM1/FM3/FM4/FM6: are out of function FM2: still working FM5: degrading

12 Satellite Performance - Reaction Control Subsystem - Pressure transducers malfunction on FM2/3/5/6. Propellant or pressurant leakage is observed on FM1/4/5. It might result from the fluids leakage from the propulsion subsystem, or pressure and temperature sensors performance degradation. FM Pressure (psi) Tank Properties Temperature ( C) Remaining Mass kg (23%) 2 Failed kg (28%) * 3 Failed No Telemetry 3.00 kg (45%) * kg (23%) 5 Failed kg (12%)* 6 Failed kg (31.8%)* [Note]:Remaining propellant mass for each satellite was summarized on 2011/3/1. * The data was calculated prior to the pressure transducer fail.

13 Satellite Performance - Computers Reboot/Reset out of 399 recorded events are computer resets/reboots as-of Most Single Event Effects (SEEs) occurred in the SAA and polar regions SC recover from system level Failure Detection & Correction (FDC) strategies ACE > BCR> Master > FC FM6 >FM5 > FM1 > FM2 > FM4 > FM3 SAA > Others > Poles 13

14 Lessons Learned -What we would do differently if we could do it again! - Items SSR/MIU GOX Data Dropouts Spacecraft Design Philosophy Spacecraft Downtime Computers Resets / Reboots ADCS Performance Reference: C.-J. Fong, D. Whiteley, E. Yang, K. Cook, V. Chu, B. Schreiner, D. Ector, P. Wilczynski, T.- Y. Liu, & N. L. Yen, Space & Ground Segment Performance of the FORMOSAT-3 / COSMIC Mission: Four Years in Orbit, Atmospheric Measurement Techniques Discussions (AMTD), Vol. 4, 2011, pp doi: / amtd

15 Conclusion FM3 stayed intermittently in Phoenix mode since 7/6/2010. Other than FM2 & FM3 power shortage issues, all the other spacecraft are continuously maintained by NSPO in a healthy state. All FMs battery have shown degradation. FM3 Battery has lost its regularity, capacity, charge functions The orders of degradation are FM4 -> FM5 -> FM6 -> FM1 -> FM2 Happy 5th Year Birthday to FORMOSAT-3 Satellites! 15

16 Acknowledgments The authors wish to thank the contributions of: FORMOSAT-3/COSMIC Program Team, including Dr. Paul Chen Mission Operation Team Flight Operation Team Spacecraft Anomaly Resolution Team (ART) Ground Operation Team Taiwan Science Teams Thank You!