Attendees: Dave
Cowley, Heather Mietz, Marc Davis, Carol Harper, Ken Dietsch, Barry Alcott,
Vern Wallace, Joe Miller, Jeff Lewis, Jack Osborne, Greg Wirth, Dave
Sprayberry, Chris Wright, Grant Tolleth, Drew Phillips, Will Deich, Chris
Lockwood
There are 120 slits per mask. This is part of the TV viewing
on the slitmask.
Sliders 3 and 4 have been mounted on DEIMOS. Slider 1 which was for the 8x11 gratings was
abandoned and a new slider (H5) for 6x8 grating was fabricated. Slider 5 is planned to be mounted after the
Pre-Ship Review but before shipping.
Gratings are in cells with handles and can be swapped
between the sliders. We are doing this
process now.
The instrument will weigh
approximately 19,000 pounds. It will
stand 163” tall not including the trolley, and 110” wide. CARA is extending the platform.
**The power on DEIMOS must
be kept on at all times. The UPS will
keep the power on for 20 minutes. The
system is set to power down after 3 minutes of no power. CCDs are sensitive to sudden power loss, so
the software is in place to shutdown gracefully.
X direction is the horizontal - the slitmask is horizontal.
Y direction is
perpendicular.
Slide 20 shows the ballpark figures.
Drew
PSFs vary as the instrument is rotated, and there is flexure
in the camera. Something could possibly
be loose. When Sandy gets back, we’ll
do zemax models to see what’s loose.
In the 20° to 0° model, the focus did not change. We will experiment with moving the
collimator before the pre-ship.
The roller chain is exposed now, but has a cover. The chain is the ultimate stop, and it does
work.
The little red buttons power the stage out of secondary
limits. There are a total of 5 big red panic buttons on the instrument: 4
around the instrument, and 1 underneath it.
Grant and Barry will talk about the fact that DEIMOS needs
to tie into Keck’s “dome e-stop” (not stop the telescope). This would stop
rotation/anything that might hurt someone.
Will – Rotation Test Results (Slide 30)
Tested the encoder positions per marks on drive disk for
repeatability (30° on drive disk).
97% of rotation was within 0-17 arcsecs.
98-99% ±17 arcsecs
Only a few times out of 400 tries were there misses of ±50
arcsecs (missed “badly”).
Next test – how well do we Servo when we move?
Two pneumatic cylinders control the hatch.
It is not under keyword control yet, but soon will be.
The cassette holds 12 slitmasks and the spec was for
10. Interlocks show if the mask is
partially in or out. The misalignment
switch will lock out if the slitmask is misaligned.
Scissorjack drives Cassette.
The hot dog drives slitmask into the frame in the focal
plane.
De is done with testing.
She has inserted it over 200 times, over a few weekends. This is over 3
months “regular” service time.
*There were 3 failures,
all using very old masks. They had been
inserted maybe 1000 times and can bend after this many uses. Also, the plunger to disengage hotdog from
mask creates extra pressure and wears down the mask.
*In two of the three failures, software recovered by
retracting and reinserting. Only one
failure required De to come up and manually fix the jam.
Vern
We are making a guide to assist with the slitmask that might
have a bend. Marc says to keep in mind
that some of these masks might only be used a few times or even a dozen. We are ordering stronger material for masks
we’ll use a lot more, like the engineering masks. Stainless is double the
strength of the aluminum ones being used currently.
Dave
Another issue is debris.
We ran a test with “fly paper”, and it did catch debris. Seems we’re wearing something out of
tolerance. We will put something in
there to catch debris; Keck wants to see this setup.
Collimator
The aluminum has been coated for 3½ years. We’ll decide whether or not to re-coat.
We have a procedure for handling the collimator.
Electronics ring supports the collimator in radial
direction.
The spreader bar to insert the collimator will come with
instrument.
There is some image motion.
Tent
Mirror
Silver overcoat will possibly go on it.
The mirror moves as part of flexure control.
It is driven at the backend by the piezo.
Bob is not here to discuss test results.
900 + 600 line grating (slide 47)
All 3 sliders (3-5) are electronically functional. These are
moved using low level Galil commands, and Dean is writing the code to do this
automatically. The transport mechanism was not as stable as we would like, so
this is why PRMs were put on them.
Marc wants gold-coated 1200 line grating. Sandy wants 831
line grating. We would need cells for
these, but we do have the covers.
Drew – All seems fine and the tilt is repeatable. It is not necessary to change the tilt in
order to change the grating.
Bob – The transport mechanism has not really been tested
except for some preliminaries. On
sliders 3 and 4, clamping is at 270° + 180°; rotated through, and curves were
in close agreement. Also, looked at 0°
+90° for slider 4. The rotation is the
same, but these are very early tests.
Harlan Epps did the overall design for the camera. There are
3 calcium fluorides. Element 5 has a fracture, but has been stable for 3-4
years. There is no leaking.
We hit all optics specifications.
‘Z’ motion is driven by delrin/invar device to stabilize a
distortion.
The dewar is bolted to the camera. The Element 9 field flattener is attached directly to the dewar.
Vern and Dave Hilyard assembled this. It is likely that there is a loose
element. Disassembly will be difficult.
The barrel of DEIMOS,
which holds the filter wheel and shutter, holds it. There always needs to be a
filter in place. Filters will have anti-reflection coating. Unsure if we need
to do a lot to change out, but it would be easy, because there are handles.
The shutter has had a failure with the screws coming
loose. This has been fixed twice.
There are 2 stages of motion; it holds 8 science chips and 2
FC chips. It was run for 4 months in the CCD lab before it came back to the
shops.
There is trouble with the cables. All 10 connectors from the CCD electronics box to controller had
issues but have been rebuilt. The new ones are not installed yet. These will be tested when we build up the
red mosaic.
The FC stage has a 4 bar mechanism with ±13 pixels. It goes forward 1mm, then hits the
window. Bob says the limited travel
range is finicky operationally.
A new can has been fabricated for the LN2 System. The plate is always in contact with the
liquid, unless it is very low. -100° is what we have maintained.
In other cooler buildings, it has gotten down to -108°. We
have operated all Lot 14 CCDs in cooler temperatures, such as -135° in other
dewars.
There is a dark current now running 1-2 electrons per pixel
per hour.
Dave Sprayberry says that for the Lot 10 blue array, we need
to provide CTE, dark current, cosmetic information, and results on temperatures
necessary to be operated on.
We are planning on building a red mosaic. It is currently being worked on through
September. It will be changed out in
October when the dewar comes out of the instrument.
Included in the red mosaic:
·
Backplane
·
8 detectors
·
2 new FC devices
Bob is pleased with the electronics in the science
controller. We’re getting a low noise
when all 16 are going. Our biggest
problem has been the AC power cord not staying plugged in. It is now clamped in place.
We have 2 VME crates. The boards will be identical and
swappable when delivered. They will be
in the control room.
There is a 40-second readout/display in the 16-amp mode.
There are 9 lamps total.
They are the pen ray-type, which are easy to change.
Quartz – Continuous fiber is fed from the electronics ring
Neon – These run warm, and we have replaced 2 so far.
These lamps are on delrin, so they are isolated.
Zinc/cad lamps – These have bare wires. Per Barry, we need to put connectors on the
lamps before we change the fan. What’s
the wattage? We might need this
information for the neon (Joe).
There are 2 copper/argon bulbs, which use 4 out of 8 fibers
in the tube (so there are spares). These are too bright for imaging mode, so
white LEDs will be used. To know when copper/argon lamp is out, Software will
have to report that it can’t find spots, etc.
This should happen.
This will be similarly implemented as with HIRES & ESI.
It uses a PXL camera. We have run this system and seen images. There is some flexure, but we hope to
stiffen this. Reference marks will be
put on the pickoff mirror.
Electronics
Enclosures
These are open now and are being worked on
continuously. There are some heating
issues with the Santa Cruz summer temperatures. However, we do have panels.
Cladding is currently being worked on. We need nose area cladding. The rotating barrel will be a shiny material
when it ships.
We need to replace the fiber in the wrap-up. This will take at least a day. This is why we have 3 running and 3 spares.
Every 10 minutes all temperatures are logged and available
via keywords. It can also be forced to
sample outside of the 10-minute cycle.
Matt Radovan is designing this now.
There is a 4 to 1 slope.
This is being tested currently. Our requirement is to run it up and off
kinematics 100 times.
Bob has updated the punchlist.
There has been lots of progress, but lots of areas in the
“pending” stage. Bob feels that it is
ambitious to do all that is expected for pre-ship.
All mechanism systems, except for grating select, are under
keyword control and have been extensively tested. There are codes for each
stage and we have run scripts.
500-600 keywords are done, so there are under 100 left to
go.
#1 area of concern is the grating select software. Key person was Dean Tucker, but a bike
accident impacted his productivity. We
will decide if we can have it done for the pre-ship review at the end of
September.
Image display – DS9 is also behind. Figure Display currently works, but it is
not an accurate display of mosaic geometry.
Images are not geometrically correct.
We are waiting for the release on DS9, which may address this problem.
FMS image read and displayed from disk, but no live
display. We are hoping the new release
will fix this problem also.
GUI – Software has not received all the observers’
comments yet. We do intend to deliver
the science GUI much like ESI, and have pop-ups and warnings.
For pre-ship all won’t need to be done (like DS9, etc.), but
grating select needs to be done before the instrument is torn down. Bob is focusing on software issues that
require the full instrument.
There are no electronics issues that worry Bob.
Work needs to be done on why the slit mask is jamming.
Rotation (Will)
·
This was also discussed earlier.
·
Mount fixes easily on Renishaw one, but there are issues
with it and Renishaw 2.
Galil
·
Dean is the main person working on it.
·
The slitmask is in good shape, but it still needs push
button integration.
·
The grating select is our biggest area of concern.
·
If it is not under keyword control, it has to be manual.
Bob has a few worries about this.
Lickserve2 – version is designed to drive figdisp and
DS9. Waiting for DS9 currently.
There will be a “gas gauge” to determine how much disk space
you have left.
All are done except the grating select. After this is done it can be dropped in.
FCS GUI – There is no prototype for this yet, but it can be
worked on when the instrument is torn down.
FCS – Most of this work will be done in Hawaii.
Documentation – Documentation will come later
on.
K testing – This occurs almost every night.
-----------------------------------After Instrument
Demonstration-------------------------------
Is there software or hardware to stop rotation if the brake
is applied? Yes.
Keck would like to discuss a buzzer if rotation is done by
hand (only if rotation by software).
Physical instrument interfaces (slide 93)
We have already been through this mostly. We will go through the interface document
tomorrow.
There will be a clear “lexan” cover on drive rollers
Is there software in place should the chain break or become
slack? If it is supposed to make a
transition, alert via software.
·
Extend the N platform (September 30, complete)
·
Reinforce N platform (September 23 or so, complete)
·
Reinforce N Deck (No firm schedule – late September
start? Hire a contractor, finish before
the end of October)
·
Design, fabricate and install the cable boom (Talk about
this tomorrow)
·
Install the N tracks on the DEIMOS side, and increase rack
on deck (by September 30; October with other deck work)
·
Increase the elevation axis telescope cable wrap (complete)
·
Run air, glycol, co-ax fiber and power lines to the cable
boom (beginning of October up to N platform)
·
Mount and install DEIMOS computers and disk drives (after
they get them from us – end of December)
·
Interface control document (discussing this tomorrow)
·
Differential guiding (before DEIMOS is up – takes 2 months –
have started)
·
Configuring of accounts
·
Data archive to tape (users will bring own drives? Observers
plugging laptops in? Remote ops have ports to do this.)
·
Telescope interlocks (has to do with boom. Will something
hang off of DEIMOS to reach? Grant –
have to work this out.)
·
Cryogen Handling (they’ve seen how it works now. Have more on Nas deck. Can go on platform?)
·
Commissioning and characterization, image reduction (Greg,
Sandy, Drew)
·
Documentation of instrument procedures (Greg will work with
us on this)
·
SW for instrument control and initialization (similar to
guider software)
·
Focus procedures (worked out during integration and testing)
Attendees: Heather
Mietz, Dave Cowley, Jeff Lewis, Ken Dietsch, Barry Alcott, Jack Osborne, Dave
Sprayberry, Greg Wirth, Vern Wallace, Chris Wright, Grant Tolleth, Chris
Lockwood
No comments
We do not have the 831line/mm grating yet, and Sandy says
she needs it. DEEP is buying this. We need to make a cell for this.
The 1200 line/mm grating has been silver-coated, but needs
to be gold-coated. We also need to make
a cell for this.
One of our clear glass filters is scratched, but well out of
focus range.
High/rho CCDs will be in when the instrument is shipped to
Hawaii. The blue mosaic will not be taken
apart.
Can we have spare LN2 cans?
Cabling – Currently the cables are in DEIMOS but are not
durable enough. But maybe spares can be had.
TV – There is no clear filter, so we have to use an open
one. One can be supplied, but Dave Cowley
needs to be notified.
There are no zinc or cad spare calibration lamps. LRIS uses these, so CARA can get some
easily.
The complete spare Dell (diskless) will be supplied.
Instrument control DEI Trader computer and RAID are one of a
kind. Celeste is unique. CARA can get spares for DEI Trader.
Bob is not here, but he agreed to this. Early on there were
failures on RAID disks, but not recently.
We have a number of spreader bars.
We’ll be getting a container at the end of DEIMOS to bring
back all our stuff. This will have to
be left at headquarters, as it is too crowded at the summit. Keck flatbeds bring stuff off the summit.
Grating file storage cabinets have not been designed yet.
We need to talk to Bill Mason about filter files storage.
No comments.
Barry will e-mail the link for the spare list on the
Electronics web page.
Shutter spares (Bimba cylinders) are not hard to
replace. They should be added to the spare
list.
Heather and Carisa need to get Electronics spares from
Barry.
The spare UPS battery has a life of 3-5 years. Lick will provide documentation on the
UPS. These will not have spares due to
their shelf life.
We have one complete spare rotation drive gearbox (spare
motor, housing).
The terminal server on KD is identical, so we have 1 spare.
Maintenance and
Electronics
We will have a manual several months after DEIMOS
commissions (like ESI).
Grant has the interface documentation, which he’ll discuss
later.
Heather and Carisa need to add, “table of contents/outline for the users manual” to the list.
We have a drawing index now.
Mechanical and electric
Mechanical Drawings (Heather and Carisa add)
Preventative maintenance manual (Heather and Carisa add)
December 3 = dewar, controllers, etc. (Carisa and Heather
add)