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Philae Science Team Meeting. CIVA Status. Venezia, Palazzo Cavalli Franchetti March 31, 2009. Civa overall status. Overall good health
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Philae Science Team Meeting CIVA Status Venezia, Palazzo Cavalli Franchetti March 31, 2009
Civa overall status • Overall good health • For what could be tested (all but the IR detectors), all systems work nominally: the 7 CIVA-P cameras, CIVA-M/V in three colours, CIVA-M/I Infrared spectral-imager.
Cratères with a pretty good image quality: resolution, focus
empty oven (# 7) empty oven (# 7) 10 µm spot
Civa status • Overall good health • For what could be tested (all but the IR detectors), all systems work nominally: the 7 CIVA-P cameras, CIVA-M/V in three colors. • Demonstrated by MSB CIVA-P images and by imaging ovens • ESB1 + MSB provided an accurate photometric calibration • SONC processing of data is perfect • But 2 concerns remained before PC8 • Data transfer quality and rate from and to CDMS (before CDMS SW upload) • Need to have access to lower integration times for CIVA/P in case of bright areas on the comet (and for ESB3) to avoid saturation.
CIVA Status: PC8 results • Extensive verification of the data transmission integrity between CIVA and CDMS in both ways, after upload of a new CDMS software. • Quality of the link has been greatly improved after the CDMS upload. • Tested with CIVA but valid for the whole payload. • Measurements of the data transmission speed is mainly unchanged with respect to previous version (up to 11 kbits/sec in direct, and 8 kbits/sec to EEPROM)
CIVA Status: PC8 results • New CIVA Software 7.8 gives access to integration times down to 4 msec. • After that upload, the instrument generated repeatedly simulated images instead of real images (both with panoramic cameras and with M/V microscope). • Simulated images are generated autonomously by the CIVA DPU instead of real images incase of detection of a transmission anomaly from the camera (interrupt counter) • The transition from nominal to degraded behavior seems related to the time of the upload. • Behavior never experienced on any ground reference model (IAS or DLR). • Need for a contingency activity slot • Request of specific activities for the PC8 contingency slot
CIVA Status: PC8 contingency activities • First activity was to repeat the PC8 panorama image acquisition : • All images were nominal !!! • the problem experienced during PC8 seems not directly related to software upgrade, but to change in the instrument environment. • Another repeat of CIVA/P and CIVA/MV acquisitions was performed, again with all data fully nominal. • The downgrade back to previous Software version has been canceled • Request of detailed analysis of the configuration of the system: • Philae configuration (use of redundant systems ?), • Temperatures, • Power supply voltage and currents, • Other ongoing activities in Philae (instruments and systems) and Rosetta Orbiter • No concluding evidences have been found yet.
CIVA : Plan / rationale for PC10 • Plan / rationale for PC10 • Standard instrument check-out. • Upload of a more robust Software in order to avoid generation of simulated images in case of partial failure of data transmission between the CIVA camera and DPU. • Software still under development and test at IAS. • Participation in integrated test sequences representative of the Comet phase: • SD2/COSAC/CIVA-M combined operations • CIVA-P participation in ROLIS SDL test with data transfer in CDMS Mass Memory • CIVA-P participation in CONSERT Interference test
CIVA : other future activities • Plan / rationale for PC 12 • Health check & Participation in integrated test sequences representative of the Comet phase, including CDMS and Lander system status. • Plan / rationale for ESB3 & Lutetia • No participation foreseen if Philae workload too heavy. • Plan / rationale for SDL • Imaging of the Lander soon after release (distance of less than 100 m) with later transfer of the data during descent if possible. • First priority remains panoramic imaging just after Landing, and quick transfer of those data to Earth (landing validation and characterization.