DEIMOS Rotator Encoders

Background

The position of the DEIMOS rotator is measured using a pair of optical Renishaw encoders that read a tape as the instrument rotates. Two units are required because the tape has a discontinuity. The following photos taken by Grant Hill show the location of these units.

Photos

The location of the left Renishaw encoder at the back of the DEIMOS barrel.

The location of right left Renishaw encoder at the back of the DEIMOS barrel.

A close up of the read head. Note that one of the two bolts that hold it in place has been removed. Note also that these bolts go through slotted holes to allow back and forth motion and there are small adjustable stand-offs to define that postion. As such, these are the preferable bolts to remove rather than the ones whose heads partially obscure the word "Renishaw".

Picture of the read head showing the window. This should be cleaned occasionally with a soft wipe and laboratory grade alcohol.

Picture showing where the other end of the read head cable ends up. The connector hanging out of the instrument connects to read head. This photo shows the left rear lower bay on the DEIMOS cradle, back by the 170 liter dewar. Note that this connector is fairly large and threading it through might be a challenge.

	DEIMOS Rotator Encoders
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Last modified: 07/10/2020 05:20 Send questions or comments to:DEIMOS Support