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A comment on James Webb telescope's coldest instrument reaches operating temperature. Parent comment

Re:James Webb telescope's coldest instrument reaches operati... by beambot on Monday April 18, 2022 @07:19PM (#31077955)
I'm having a hard time understanding the axial motion from the coarse adjustment. From [0]: The Ball Screw in Figure 9 has a 21 mm range. As the ball screw nut moves up, the housing moves up too -- but then the two halves of the tumbler coupling get displaced in such a way that doesn't seem to support a 21mm displacement. How does the tumbler coupling stay mated? (I feel like I'm missing something obvious?)
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Re:James Webb telescope's coldest instrument reaches operati... by phinnaeus on Monday April 18, 2022 @11:24PM (#31079481)
Why are you supposing that the two halves of the coupler are moving apart? They are both attached to the moving section
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Re:James Webb telescope's coldest instrument reaches operati... by beambot on Monday April 18, 2022 @11:30PM (#31079507)
Figure 9 implies that the coupler drives the blue gear (shaft of lead screw).

But let's assume you are right: Then how does the blue gear at top of the lead screw simultaneously turn the shaft and move upwards too?

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Re:James Webb telescope's coldest instrument reaches operati... by Linosaurus on Tuesday April 19, 2022 @04:37AM (#31080849)
I believe that everything in figure nine moves together vertically except the yellow/orange ball screw nut and pink horizontal thingie, these are fixed to the satellite.

The sensor and stabilizer on the right side are flexible.

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Re:James Webb telescope's coldest instrument reaches operati... by formerly_proven on Tuesday April 19, 2022 @04:39AM (#31080861)
https://www.youtube.com/watch?v=5MxH1sfJLBQ
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