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Pictures and GAM-lite Testing
Date/Time
20230114-T14:30 - 20230114-T1900
People
Roy, Gabriel
Spaces Occupied
401, 433C, Dome
Goals
Document GAM on wiki
Investigate and repair GAM as possible
Clean-off mirror doors
Develop Software Webpage
Develop Motors Webpage
Test GAM-lite Focus/Design
Determine the name of the box the GAM is controlled/powered by(?)
Log
Take images of GAM internals and write-up GAM
EXPLORE GAM
Pulled off east port plate on GAM
Investigated translating stage drive & motor
Seems like hand crank (Item 113 in ENGR Drawings GAM; GAM 011) is meeting friction and is very noisy
Investigated On-Axis Filter Wheel drive & motor
Belt (BERG 31BFG), is missing some teeth, but seems OK. Might be good idea to get a new one.
For new BERG 31BFG, it looks like you buy a long length of it and cut it/fasten it to the size you need
Since it's clear that the translating stage motor isn't working as expected (GAM tests), we removed the entire east-plate for further inspection
The BERG belt connecting the potentiometer that acts as the encoder for the translating stage position is actively breaking. We think due to age, but it could also be due to some misalignment we aren't aware of
There are other BERG belts that may be in a similar state, namely for the On-Axis Filter wheel
We inspected the pin-outs between this motor (translating stage), and confirmed they agree with ENGR Pkg GAM 349-209.
Further, we removed the AMP 37-pin terminal port from the south plate in an attempt to better inspect the wiring.
This is difficult since there isn't a lot of slack in the wires and we are unwilling to disassemble the GAM further.
Possible appropriate next steps are to get the extender cables and completely disassemble the GAM while testing each component
(above) This is the AMP 37-pin terminal port. Ports 7-12 drive the translating stage motor. See ENGR Pkg: GAM 349-209
(above) this is the pin connector Erik installed to interface to the translating stage motor. These wires correspond to ports 7-12 on the 37-pin terminal port to the left. See ENGR Pkg: GAM 349-209
(above) This is a view of the GAM from the east plate, looking west. You can see the green pin connector (middle image) near the center.
You can also see the translating stage screw that the motor drives on the left. Directly beneath that is the BERG orange belt that interacts with the potentiometer to encode the translating stage position.
At the top-right of the view is the motor driving the guide-probe Y-position (Roy thinks). More information on this motor is available in the ENGR Pkg: GAM-026, "X-Y Stage Assembly"
ToDo
Get coat rack/place for things off the ground
Remove Sky & Telescope annals
Ask Belay about Cloud Monitor
Find FLIR Camera
Roy sent Dominik an email
Dominik write back, he took it. We will include in inventory and have a better way to sign things out.
Hand Crank for Translating Stage is noisy and meets friction, lubricate/repair with Erik's help
Invest in extension cables and disassemble the GAM while inspecting each part ... This is gunna take a while
Figure out why GAM switch needs to be flipped
Clean Mirror Doors
Wipe down telescope, in general
Test new finderscope mount
Calibrate finderscope to be better aligned with DFM Scope
Notes
Related content
Direct Questions/Concerns to Roy Prouty (roy.prouty@umbc.edu)