ATST Virtual Instrument Concept

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ATST Virtual Instrument Concept

• ATST Conceptual Design Review
• 27 Aug 2003

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Virtual Instrument

• Science requirements
• Flexible, laboratory-style environment
• Save the data and the associated component
  states.
• Software must not constrain the requirements
• (but it does constrain the solutions!)
• A model for instrument development
• Delivery of a standard instrument template to
  build upon
• Common control behavior
• Simplified instrument setup and take down
• Code reuse reduces overall development costs and
  improves maintainability
• The Virtual Instrument is discussed in ATST
  Document RPT-0011

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Component Model

• There are no instruments
• only experiments needing control over components
• (Ok, some canned sets of components comprise
  facility instruments ViSP, NIRSP, ViSTF, WBF,
  etc.)
• Synchronicity provided by software and
  communications bus
• Ownership, start/stop times, index
  synchronization.
• AO and Telescope are also components that may be
  shared among virtual instruments

Physical Device
Software Device
Component
Container
Virtual Instrument
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Accessible Services

• Command Channel
• sends synchronized messages
• Connection Service
• Register name and find others by name.
• Database Service
• Get defaults, save headers.
• Notification Service
• Subscribe and publish events.
• Archive Service
• Log and debug information.
• Synchronization Service
• Hardwired connections

Connection Service
Database Service
get defaults save headers
register find others
Component
commands
log debug
subscribe publish events
Notification Service
Archive Service
Synchro Service
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Types of Components

• High-level Components
• Sequencers send commands in order and synchronize
  the responses.
• Controllers execute downloaded scripts.
• Mid-level Components
• Multi-axis, data handling.
• Low-level Components
• Cameras Spectographs Mechanisms Others
• Near-IR Visible Slit Jaws AO
• Thermal IR Near-IR Dichroics Polarizer
• Visible Thermal IR Filter Wheels Rotator
• Lyot Stops WFS
• Tuneable Filters Telescope

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Virtual Instrument
OCS
TCS
ICS
DHS
TCS
Component
VI
ViSP
VisTF
VI
VI
NIrSP
VI
Component
Component
Available Components
Driver
Component
Component
Component
Component
Component
Component
Driver
Component
Driver
Component
Driver
Component
Component
Component
Component
Component
Component
Driver
Hardware
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An Instrument Configuration
AO
AO-Cam
Image
ATST Coude Focus
G-Band
Visible High Resol. Spectroscopy
Image
dichroic
Reflection slit-jaw
Visible Polarimetry
Near-IR Polarimetry
WL Camera
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An Instrument Configuration Redux
VI
TCS
AO
Sequencer
Camera
Visible Polarimeter
Visible Camera
Dichroic
Near IR Polarimeter
G Filter
Visible Camera
G Filter
G Filter
Slit Jaw
G Filter