The  Mechanical Design of the Second The  Mechanical Design of the Second and third Antarctic Survey Telescopeand third Antarctic Survey Telescope

Wen Haikun

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Outline• 1. The Tube Design • 2. The Drive System Design• 3. The Low temperature test• 4.The AST3-3 Mechanical Design

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Sealing Structure

Temperature compensation Structure

Titanium alloy

The Tube Structure Design

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Bending angle

• Corrector mirror:2.84″

• Primary Mirror:2.12″

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Primary Mirror Supporting Structure

• 9 point whiffle tree structure

• Fixed position in the middle hole.

• Flexure supporting structure

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The stress and the deformation of the Mirror shape

• The max stress value :0.425Mpa

• The defromation of the mirror surface shape:

PV Value :43.7nm ， RMS Value:7.2nm 。

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The focal plane System

• Switch the filter• Auto-focus system• Thermal dissipation

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Deformation of the drive system

Deformation in the east-west directionMax displacement:0.935e-04mm

Deformation in the north-south directionMax displacement:0.884-04mm

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Buffer and limit position structure

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Reducer improvement

• Increase the rigidity of the reducer

• The lowest frequency :14.8Hz

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The Low temperature Test

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Mo He winter test

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Picture in the Anatarctic

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The tube of the third telescope

• Move the CCD to the outside of the tube

• Solve the heat problem

•  easy to install and maintain

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The drive system of the third telescope

• Adjust the gaps of the gear

• Increase the rigidity of the reducer

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Thankyou