ATST Virtual Instrument Concept

ATST Conceptual Design Review

27 Aug 2003

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

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

PhysicalDevice

SoftwareDevice

Component ContainerVirtual

Instrument

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

Component

ConnectionService

DatabaseService

NotificationService

ArchiveService

commands

register &find others

get defaults &save headers

log & debugsubscribe &

publish events

SynchroService

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 ComponentsCameras 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

Available Components

Virtual Instrument

OCS

ICS DHSTCS

ViSP VisTF VI VINIrSP VI

Component

Component

Component

Component

Component

Component

Component

Component

Component

Component Component

VI

Component

TCS

Component

DriverComponent

DriverComponent

DriverComponent

DriverComponent

Driver

Hardware

ATST Coude Focus

AO AO-Cam

G-Band

Visible Polarimetry

dichroicImage

Image

Reflection slit-jaw

Near-IR Polarimetry

Visible

High R

esol.

Spectroscopy

WL Camera

An Instrument Configuration

An Instrument Configuration Redux

VITCS

AO

Camera

G Filter

G FilterG Filter

G FilterSlit Jaw

VisiblePolarimeter

G FilterG Filter

G FilterSlit Jaw

VisibleCamera

DichroicNear IR

Polarimeter

VisibleCamera

Sequencer