Instrument Control System

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Instrument Control System
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Duplicate NIRI Control System
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Input Output Controller
Motor Control
Digital I/O
Gemini LAN
A/D Converter
Wavefront Sensor
VME CPU
Serial I/O
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The Input Output Controller A series of
externally manufactured PCBs used in control of
and communication with the NIFS instrument.

• 1x Oregon VME8-8 Stepper Motor Controller.

• 1x XYCOM XVME-240 Digital I/O Board.

• 1x Gemini Network Interface Board.

• 2x XYCOM XVME566 Analogue to Digital Converters .

• 1x VME CPU/Epics IOC.

• 1x XYCOM XVME-400 Serial I/O Board.

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Optical Component Controller
Motor Control
A/D Converter
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The Optical Components Controller is responsible
for moving and positioning all optical elements

• OIWFS X-Axis Gimbal Screw.

• OIWFS Y-Axis Gimbal Screw.

• OIWFS Filter Wheel.

• Spectrograph Focal Plane Mask Wheel.

• Spectrograph Order Blocking Filter Wheel.

• Spectrograph Grating Wheel.

• Environmental Cover.

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Optical Component Controller
Motor Control
A/D Converter
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The Optical Components Controller All optical
elements may be categorised as either

• Rotary Controlled Elements.
• Linear Controlled Elements.
• Open/Closed Elements.

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Rotary Elements

• Moved by dead reckoning from a datum position by
  counting stepper motor steps.
• Positioned absolutely by a detent system.

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Rotary Elements

• Datum position determined by magnet and Hall
  effect sensor pair.
• Additional magnets and sensors may be added to
  improve reliability.

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Linear Elements

• Positioned by dead reckoning by counting stepper
  motor steps.
• Datum position is determined by magnet and Hall
  effect sensor pair on the main spur gear.

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Linear Elements
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Open/Closed Elements

• Environmental Cover position, either Open or
  Closed, is determined by limit switches.

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Temperature Controller
A/D Converter
Serial I/O
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Temperature Controller
The Temperature Controller is responsible for

• Cool-down.

• Temperature regulation of science detector.

• Temperature regulation of OIWFS detector.

• Temperature regulation of CWS plate.

• Warm-up.

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Temperature Controller
A/D Converter
Serial I/O
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Cool-Down

• Cooling is accomplished by twin Coolpower 130
  Cryocoolers.
• Primary stage is coldstrapped to the cold work
  surface.
• Secondary stage is coldstrapped to either the
  OIWFS detector or to the science detector.
• Cooling rate is varied by changing the pump speed.

Two stage cryocooler 15W_at_20K 115W_at_77K
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Temperature Regulation

• NIRI - Three Omega CY321 Temperature
  Controllers.
• Science detector requires ?1 mK.
• Use Lakeshore Model 340 Temperature Controller.
• Dual 100W/1W PID controller.
• Cernox? temperature sensor.
• RS232 link via XYCOM XVME-400 Serial I/O.
• Additional thermistors for temperature
  monitoring.
• Preamps on Hall effect sensor board.
• Linked to XYCOM XVME566 Analog I/O.

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Warm-Up

• Warm-Up is accomplished by raising the set-point
  of the temperature regulators in a controlled
  fashion.
• With additional power being diverted from the
  stepper motor power supply.
• Detectors maintained at a higher temperature in
  order to limit any possibility of sublimation.

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NIRI Duplication Issues

• Encoding Performance.
• Temperature Regulation.
• Cool-Down Time.
• Warm-Up Time.

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