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FT T / NA S & FLC Software & Controls

Software Requirements and Next Steps
Technical Meeting #3, 14 May 2010 John Young


Outline


Requirements for FTT/NAS & FLC control software
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Includes top-level and derived requirements Grouped sensibly Anything missing? For discussion



Suggested next steps
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Fast Tip-Tilt/ Narrow-field Acquisition System


First Light Camera


The FLC will be operated in two distinct roles:
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Standalone role


Mainly for commissioning/acceptance testing of UTM:
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Manual target acquisition, development of pointing models Open-loop tracking tests



Controlled from FLC GUI, independent of the MRO ISS Used to integrate UT with ISS prior to FTT/NAS delivery NAS functions from FTT/NAS
­

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"Subsystem" role


e.g. automatic target acquisition and tracking


Operating Environment(s)


Conventional x86 PC?
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Need PCI bus (with bus-mastering) for Andor camera Need Ethernet port for Princeton camera Need 2GB storage for recorded data Total power consumption for FTT system < 250W Interface to ISS? Run user interface application?



Second PC??
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Need to be able to operate system from NMTsupplied laptop


Use Cases


Not defined yet


Use Case Example


Functional Requirements


Operating Modes


Idle Mode Acquisition Mode Acquisition Check Mode Fast Tip-Tilt Mode (not FLC) Dark Frame Mode Flatfield Mode


Control software implements single FTT/NA or FLC system


High-level commands for switching operating mode and use case tasks Low-level commands for basic component functions





Need to define commands


ISS Interface Framework


Code-generation frameworks available to implement TCP/IP messaging to/from ISS
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Java C & C-no-threads Receive commands and signal completion/return result Configure and transmit monitor data Transmit faults and alerts Save log messages to local file Save and retrieve configuration data




All of these frameworks provide capability to:
­ ­ ­ ­ ­

e.g. dark and flatfield frames


System Configuration


System retrieves configuration from ISS Database Manager during initialization:
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CCD readout parameters Servo parameters ...



Updated configuration data transmitted to DBM on completion of a calibration procedure


Data transmission to ISS


System transmits monitor data to ISS Data Collector [location TBC]:
­ ­ ­ ­ ­ ­ ­ ­

All calibration parameters; Raw centroid estimates; Flux estimates; Dispersion and off-axis offsets; UT mount acquisition/tracking corrections; FTTA demands; Spatial and temporal (goal) seeing estimates; Copies of all rotation matrices used by the system.



Individual monitor points can be deactivated or decimated, to save network bandwidth


Standalone Operation


Operation without ISS using supplied GUI FTT/NAS only:
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Testing without any or all of ISS, FTTA, UTM


Appropriate reductions in functionality permitted

­

Standalone archiving capability


End of Functional Requirements


Key Performance Requirements


Frame rate > TBD Hz (derived) Latency between CCD exposure and output of TT correction < TBD s (derived) Centroid accuracy




Computations and Algorithms


Centroiding
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Use of master dark & flatfield frames Objective point moves



Spatial and temporal (goal) seeing estimates FTT Servo
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User-selectable closed-loop 3dB bandwidth: 10­40Hz (goal 1­50Hz) Coordinate transformation between CCD & FTTA axes Sinusoidal dither facility

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Acquisition Servo


Hardware Interfaces


EMCCD Camera
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Andor: PCI Princeton: Gigabit Ethernet Both require custom driver for FTT? (but not for FLC?)



Analogue output to FTTA Timing board?
­

IRIG-B available for FTT



Actuators and tellbacks for FTT optics (TBD)


FLC & FTT/NAS GUIs: Common Requirements


Capability to display and operate from:
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NMT-supplied Linux computer in the MROI control room NMT-supplied laptop in UTE



Display-only mode, when controlled by ISS


FTT GUI (i)


Control of all FTT/NA system functions, including diagnostic functions; Live display of acquisition mode images, at the full frame rate; Live display of FTT mode images, at a reduced frame rate of 10 Hz; Live display of sequences (i.e. graphs) of monitor data;








FTT GUI (ii)


When using the stand-alone recording capability:
­

A posteriori display of individual image frames (captured in any of the FTT/NA modes); A posteriori display of sequences (i.e. graphs) of monitor data.

­



Able to run while sending to ISS data collector Allowed to use multiple GUI applications to satisfy these requirements


FLC GUI (i)


Remote display of full frame images (60" FOV) at exposure sampling rate Enlarged display of user-selected region of the full frame images Able to compute centroid of selectable star w.r.t. user-specified fiducial point
­





Display cross-hairs at the fiducial point


FLC GUI (ii)


Live numerical display of average and rms centroid on GUI, update interval equal to averaging time (user-specified 100­5000 ms)
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Display of 10 most recent average and rms values



Log time-series of raw centroids to ASCII CSVformat log-file on user command
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Accompanying UTC time-stamps accurate to 1 ms Logging stops after a user-specified duration or when interrupted by the user Log-file accessible via a network shared drive

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Communications Interfaces


Standard ISS TCP/IP protocols over Ethernet:
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Command/data interface Monitor data interface Configuration interface to MCDB Interface to Publish-Subscribe System



Communication with UTM is via ISS


Next Steps


Derived requirements Decide on operating environment(s) Define software components and functions Define high-level commands Start thinking about algorithms