SMT Control SystemSMT Control System

Steward Observatory Faculty Meeting May 02, 2003

Arizona Radio

ObservatoryThomas W. Folkers

SMT: SpecificationsSMT: Specifications

• Elevation: 10,435 ft.• Dish: 10 Meter. F/D = 0.35• Mount: Azimuth – Elevation.• Focus: Nasmyth or Bent Cassegrain.• Surface: 60 Adjustable CFRP Panels.• Accuracy: 15 microns RMS.• Pointing: < 2 arc seconds, RMS on

Sky.• Tracking: < 0.2 arc seconds. RMS• Support: CFRP & Steel.• Total Weight:41,500 Kg, (46 Tons)• Building: 650 Tons.

Old SMT Control SystemOld SMT Control System

• VMS Based Vax System.• Telescope Commissioned in 1993 with

Outdated CAMAC Bus System.• Spare Parts Increasingly Impossible to Come by.• Monolithic Control System Design.• Limited Data Acquisition Speed.• Text Based Interface.• No Remote Observing and Limited Debugging.

New Control SystemNew Control System• Graphical User Interface. ( Xwindows )• Network Based Distributed Parallel Processing.• Remote Observing.• Remote Debugging.• Remote Operation Possible.• Higher Data Rates. ( Up to 20X for OTF)• Non-Propriety Hardware. ( PCI / ISA / PC104 )• Non-Propriety Operating Systems. ( Linux )• Compatible with 12 Meter.

Operator’s Control ComputersOperator’s Control Computers

• Main Control Computers:– (3) Dual Pentium Processor Systems.– Six LCD Displays.– Runs All Non Real Time Processes.– Displays all Status and Data Readouts.

SMT Control RoomSMT Control Room

Computer RoomComputer Room

Before After

Computer Room (before)Computer Room (before)

Computer Room (After)Computer Room (After)

Spectral Line BackendsSpectral Line Backends• Filters Banks:

– VxWorks Based.– 128 x 62.5 Khz Filters.– 256 x 250 Khz Filters.– 256 x 1 Mhz Filters.

• Acousto-Optical-Spectrometers:– RT-Linux Based.– (3) Units of 2048 Channels each.– (2) 1 Ghz Bandwidth. 1Mhz/Channel.– (1) 250 Mhz Bandwidth. 385 Khz/Channel.

• Chirp Transform Spectrometer:– RT-Linux Based.– (3) Identical Units of 4096 Channels.– 183 Mhz Bandwidth. 43Khz/Channel.– (1) Unit Installed.

Spectral Line OTF Map

Continuum BackendContinuum Backend

• Digital Back End:– RT-Linux.– Capable of Capturing Data From 1 of 2 banks

of 20 backends simultaneously.– Generates Station Timing Signals.

DBE ComputerDBE Computer

19 Channel Bolometer Continuum OTF Map

Auxiliary Telescope SystemsAuxiliary Telescope Systems

• Apex Control Computer:– Sub-Reflector Nutation.– Telescope Focus.

• FMS Control Computer:– GPIB Control of IF & LO Synthesizers.– Reads Inclinometers & Building Currents.– Receiver IF & LO Routing Switches.

Pointing SystemsPointing Systems

• Optical Pointing:– Linux Based Frame Capture System.– Apogee KX1E CCD Frame Transfer Camera.– 768 x 512 Pixel Resolution.– 0.766 Arc Second/Pixel.– 30ms to 173 Minute Integration Times.– Thermo-Electrically Cooled.– Used to Fit 4 of 9 Pointing Model Parameters.

Pointing Systems: (optical)Pointing Systems: (optical)

10 Minute Optical Exposure.10 Minute Optical Exposure.

Digitally Enhanced Histogram

Pointing Systems (cont)Pointing Systems (cont)

• Inclinometers:– (2) Sets of Orthogonal Mounted

Inclinometers.– Use to Monitor Telescope Mount Tilt.– Real Time Updates of Tilt Terms.

Pointing Systems Pointing Systems (inclinometers)(inclinometers)

Analysis SystemsAnalysis Systems

• Observer Workstation:– Dual Processor

Pentium.– Dual LCD Displays.– 150 Gbytes Storage

for Reduced Data.– Linux Based Analysis:

• Class• NIC• Aips• Unipops (Future)

File ServerFile Server

• File Server:– 360 Gbytes of Raw

Data Storage.– All Spectral Line Data

Handling Processes Run Here. Minimizes Data Transfer Time.

Future PlansFuture Plans• Additional Observer’s Linux Workstations At

Both Mt. Graham and in Tucson.

• Remote Observing Station in Tucson.

• Improved Continuum Pointing Routines.

• Kitchen and Lounge On-Line Displays.

NOTE: Power Savings: Old System vs New.UPS Load Reduced from 65% to 42%.A Difference of 5.52 KW. @ $0.32 per KWHWe Save ~$15,400 / Year.