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FTT/NAS vs FLC Comparison of Technical Requirements

INT-403-ENG-0115 rev 1.1 May 20th, 2010

Magdalena Ridge Observatory New Mexico Tech 101 East Road Socorro, NM 87801 http://www.mro.nmt.edu/


CONTENTS

CONTENTS

Contents
1 2 Introduction FTT/NAS vs FLC 2.1 2.2 2.3 2.4 2.5 Functional requirements comparison . . . . . . . . . . . . . . . . . . . . . . . Performance requirements comparison . . . . . . . . . . . . . . . . . . . . . Software requirements comparison . . . . . . . . . . . . . . . . . . . . . . . . Thermal, power, maintenance comparison . . . . . . . . . . . . . . . . . . . . Interface requirements comparison . . . . . . . . . . . . . . . . . . . . . . . . 3 4 4 5 6 7 7

Change Record
Revision 0.1 0.2 1.0 1.1 Date 2010-04-12 2010-04-23 2010-05-19 2010-05-20 Authors JSY JSY JSY JSY Changes First draft Second draft Added document identifier, no other changes Updated version numbers of referenced documents, no other changes needed

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CONTENTS

CONTENTS

Objective
To compare the technical requirements for the Fast Tip-Tilt/Narrow-field Acquisition System with those for the MROI First Light Camera that will be used initially.

Referenced Documents
The following documents are incorporated by reference: INT-403-ENG-0003 rev 2.2 "Technical Requirements: Fast Tip-Tilt/Narrow-field Acquisition System" INT-403-TSP-0107 rev 1.0 "Technical Requirements: First Light Camera"

Acronyms used in this document
API Application Programming Interface FLC First Light Camera FOV Field Of View FTT Fast Tip-Tilt FTTA Fast Tip-Tilt Actuator FWHM Full Width at Half Maximum GUI Graphical User Interface ICD Interface Control Document ISS Interferometer Supervisory System MROI Magdalena Ridge Observatory Interferometer NA Narrow-field Acquisition UT Unit Telescope UTM Unit Telescope Mount WFE WaveFront Error

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1 INTRODUCTION

1

Introduction

The First Light Camera (FLC) system will be used for commissioning and integration of the first AMOS-delivered Unit Telescope (UT) at the Magdalena Ridge Observatory Interferometer (MROI). The FLC will be a precursor for the more capable Fast Tip-Tilt/Narrowfield Acquisition System (FTT/NAS) described in INT-403-ENG-0003: owing to delays in procuring the FTT/NAS, the FLC is being procured to coincide with the arrival of the first UT. The FTT/NAS will be delivered later and will replace the FLC for regular MROI scientific operations. This document is intended to clarify the relationship between the FTT/NAS and FLC technical requirements. The following sections contain tables enumerating the FTT/NAS requirements. For each requirement, there is an indication of whether an identical requirement applies to the FLC, and if not, whether an alternative (typically less stringent) requirement applies. Additional requirements specified by the UTM vendor apply to the FLC -- please consult INT-403-TSP-0107 for details. The content of this document is for information only and is not intended to specify any requirements for either the FTT/NAS or the FLC.

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2 FTT/NAS VS FLC

2

Comparison of FTT/NAS and FLC Requirements

2.1 Operating mode & functional requirements comparison
FTT/NAS Req. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Same for FLC? Yes Yes Yes No N/A Yes Yes Yes Yes Yes Yes Yes Yes Yes N/A No No No No No N/A N/A FLC-UR 1-03 1-01 1-02 Description Mode switching time < 5 s Provision of idle mode Command response (idle mode) Provision of fast tip-tilt mode Estimate image FWHM in fast tip-tilt mode at 0.1 Hz Provision of acquisition mode Estimate of image FWHM in acquisition mode Provision of acquisition check mode (Exp. time 10 s) Provision of dark frame mode Master dark frame transmission and retrieval Use of dark frame Provision of flatfield mode (Exp. time 100 s) Master flatfield frame transmission and retrieval Use of flatfield Coordinate transformations Sensor spectral bandwidth: 350­ 1000 nm Space for future dichroic slide Application of dispersion offset Off-axis tip-tilt sensing distance 10 arcseconds Facility for accepting & using off-axis offsets Continuous tracking through offset changes Linearity of centroiding Comments Goal 1 s

1-01 1-02 1-01 1-01 1-02 1-02 1-01 1-02 1-02

Offsets delivered at 1 Hz

Multiple exposures permissible

Multiple exposures permissible

Alternative FLCUR2-03

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2.2

Performance requirements comparison

2 FTT/NAS VS FLC

Operating mode & functional requirements comparison continued
FTT/NAS Req. No. 46 47 48 49 50 51 52 53 54 55 56 Same for FLC? N/A N/A No N/A Yes Yes Yes No N/A N/A N/A FLC-UR Description Fast tip-tilt mode FOV 3 в 3 Closed-loop 3dB bandwidth: 10­40 Hz Sinusoidal dither facility: 2 at up to 10 Hz Latency of dither function 1 ms Acquisition mode FOV 60 в 60 Selection of (tip-tilt) reference object Facility to override reference object selection Relocation procedure Provision of relocation hardware Withstanding shock-loads of X g Relocation time 2 hrs Comments

2-01 1-02 1-02

Goal 100 в 100 (FTT/NAS only)

2.2 Performance requirements comparison
FTT/NAS Same for Req. No. FLC? 57 No FLC-UR Description Environmental conditions for operation: Electronics housing temp in range +10 to +40 C, ambient temperature in range -5 to +20 C, ambient relative humidity in range 10% to 70% Environmental conditions for survivability: ambient temperature in range -25 to +40 C, ambient relative humidity in range 5% to 95% Dichroic clear aperture 110 mm Dichroic throughput 97% Dichroic diattenuation 1% Dichroic surface quality: 60:40 or better Dichroic transmitted WFE 16.4 nm Limiting magnitude for acquisition V = 16 Residual tip-tilt in fast tip-tilt mode 0.015 at V = 16 or brighter Stability of tip-tilt zero-point: 0.015 for T 5 Comments Alternative FLCUR2-16

58

No

Alternative FLCUR2-16

59 60 61 62 63 64 65 66

N/A N/A N/A N/A N/A No N/A No

Alternative FLCUR2-07

Alternative FLCUR2-15

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2.3

Software requirements comparison

2 FTT/NAS VS FLC

2.3 Software requirements comparison
FTT/NAS Req. No. 23 24 25 26 27 28 29 30 31 32 33 34 Same for FLC? Yes Yes No Yes Yes Yes Yes Yes No N/A N/A No FLC-UR 3-04 3-05 Description Provision and documentation of API Control of system functions using API Demonstration of GUI(s) Operation of GUI(s) from control room Disabling of GUI controls Operation from laptop Run GUI while streaming to ISS data collector Operation without ISS, (FTTA), UTM Stand-alone archiving capability Recording/display of multiple datasets Local storage for detector image data and telemetry 2 GB Stand-alone image recording at userselectable rate rate of original acquisition Stand-alone telemetry data items Stand-alone recording: time-stamps accurate to 1 ms Data transmission to ISS Time-stamps on data transmitted to ISS accurate to 1 ms Reduced-data-rate low-latency (0.2 s) transmission to ISS Sub-sampling for reduced data rate (at 10 Hz) Reduced-data-rate telemetry items to ISS Full-data-rate high-latency (300 s) transmission to ISS Reliable protocol for full-data-rate transmission to ISS Full-data-rate telemetry items to ISS Alternative: Full-data-rate low-latency (0.2 s) transmission to ISS Comments

Alternative FLCUR2-09 & 2-10

2-09 3-03 3-09 3-03 1-04

Alternative FLCUR2-14

35 36 37 38 39 40 41 42 43 44 45

N/A N/A Yes Yes N/A N/A N/A N/A N/A Yes Yes 3-06 3-08 3-06 3-07

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2.4

Thermal, power, maintenance comparison

2 FTT/NAS VS FLC

2.4 Thermal, power & maintenance requirements comparison
FTT/NAS Req. No. 67 68 69 70 71 72 Same for FLC? No No No No No No FLC-UR Description Use of electronics housing Surface temp close to beam path within 2 C of ambient Total power consumption 250 W Routine maintenance interval 3 months Design lifetime of 10 years Provision of maintenance plan for control system software & hardware Comments

2.5 Interface requirements comparison
FTT/NAS Same for Req. No. FLC? 73 Yes 74 No FLC-UR FLC-UR3-01 Description Provision of list of ICDs and enumeration of authors Compatibility with agreed space envelope Comments

FLC may use all of Nasmyth table

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