Instrument Control Systems 2014 ESPRESSO TCCDs

Field and Pupil Stabilization Field stabilization: maintain the object centered on the fiber during the whole duration of the scientific exposure Pupil stabilization: maintain the pupil stable during the observation Devices involved in FPS: 8 TCCDs (2 for each F/E arm, one for FS and one for PS) 8 F/E piezo tip-tilts (2 for each F/E arm, one for FS and one for PS) 4 ND filters (1 TCCD for EXPM)

Acquisition & Field and Pupil Stabilization GUI (1 UT and 4 UT cases)

FS sequence diagram

FPS TCCD Standard VME-based ESO TCCD not adopted: Cost (~30 k€ for each TCCD) ESPRESSO electronics based on PLCs Trade-off among different TCCD brands: Apogee Aspen CG285: Overlap mode produces corrupted images Jitter in frames arrival time Power supply connector problem AVT Manta G145B NIR AVT Bigeye G-132 B cool (adopted, better performances than AVT Manta)

TCCD Device Driver will be provided by ESO (images from ESO document: Technical Detector Control Software for COTS Cameras - Design Description)

TCCD device driver Temporary TCCD Device Driver implemented by OATs New boss interface created (bossINTERFACE_3GTCCD)

TCCD performance tests Minimum requested correction frequency needed to reach the required stability and precision: 3 Hz The TCCD acquires the images in continuous loop with ExpTime = 0.1 sec The acquired image is transferred to the shared memory A client process takes the image from the shared memory (when ready) and writes the Δx and Δy corrections in the On Line Database The elapsed time between 2 consecutive OLDB writings is computed

TCCD performances

AVT Bigeye performances

AVT Bigeye performances