APS Formation Sensor

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APS Formation Sensor

• MECHANICAL DESIGN
• Rodger Farley
• 15 March 2002

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Requirements

• Survive launch loads, of course.
• Once on orbit, to keep the 6 optics stable
  relative to each other to
• 10 microns. With an aluminum housing, this
  translates to keeping the temperature steady to
  0.25 deg C.
• Provide re-closable lid
• Provide 3 element filter wheel and unfiltered
  path, not particularly sensitive to positional
  placement or repeatability. Agility of the
  wheel is not yet specified.

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General Arrangement
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General Arrangement
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Design Elements, Modules

• 
  Total Mass
• Front Baffle Module
• Baffle
• Re-closable lid
• Light ring
• Telescope Tube Module
• Outer tube, with proportional heater system
• 2 optics sub modules
• Isolation adapter module
• Titanium thermal isolation housing
• Filter wheel mechanism
• Detector / camera module
• Flexured base plate

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Front Baffle Module

• Baffle
• Motorized lid with labyrinth edge, spectralon
  surface on lid back
• Ring of lights

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Telescope Tube Module

• Aluminum tube for good thermal conductivity,
  minimize gradients
• Temperature controlled to room temp /- 0.25 deg
  C with proportional thermal control system of
  heaters and sensors.
• Optics aluminum sub modules with bonded glass
  elements on triangular shaped flexure blades.
• Optical elements in sub modules are pre-metered
  for ease of integration, and have registration
  pads that can be lapped.
• Sub modules are muzzle loaded into the outer
  tube, and preloaded with compliance using a wave
  ring washer and threaded ring. The sub modules
  bear against their own registration pads and the
  outer tube registration surfaces.

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Telescope Tube Module
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Isolation Adaptor Module

• Titanium housing, flexured from the telescope
  tube module
• Filter wheel with 4 elements (one blank)
• D.C. brushless motor with encoder

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Camera Module

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Flexured Base Plate

• Titanium flexures
• Honeycomb plate