IMACS progress report no. 40

B. Bigelow						3 August 2001

	Project Status

Currently scheduled tasks:				Status:

a)	DSS drafting (Cleary)				IP 
b)	DSS fabrication (Kowal, Castillo)		IP 
c)	Filter server assy. (2) (Asa)			IP
d)	Field lens mechanics fab (Martinez & Turek)	on schedule
e)	Calibration system mech. des. (Hare)		IP 
f)	Collimator mechanics fab (M&T)			done
g)	Coll. opto-mech assembly (Bigelow)		late start 
h)	Long camera fabrication (Martinez & Turek)	90% compl.
k)	Principal Guider Camera fab (Storts)		90% compl.
l)	Science Array controller fab (Burley)		95% compl.
m)	Short Camera mech. design (Bigelow)		done
n)	Short Camera drafting (Cleary)			on sched.
o)	Filter procurement (Sutin)			on sched.
p)	Grism procurement (Sutin)			on sched.
q)	Motion control (MC) electr. design (Carr)	95% compl.
r)	MC fab. (Asa)	    				50% compl.
s)	Control software design (Birk)			on sched.

Project events:

The field lens was successfully Sol-Gel coated at Cleveland Crystal in
July.

A contract for AR coating of the long camera lenses, and two
collimator lenses was let to Spectrum Thin Films.  The coated lenses
are due in August.

Latest construction images can be seen on the IMACS web site:

http://www.ociw.edu/instrumentation/imacs

Check out new images of:

     Long camera fabrication work at Martinez and Turek 
     Preparation for collimator lens mounting 
     Center field guider camera assembled
     Shutter exposure time testing

	Optics (Sutin)

1) Field Lens:

    Cleveland Crystal said (2001-07-23) that they intended to dip
    either 2001-07-23 or 2001-07-24. (The coating is complete, and 
    the field lens is currently being shipped to OCIW). 

2) Spectrum Coatings:

    Spectrum is hoping to do the last few iterations on the coating
    design and do the coatings for the long camera and smaller
    collimator elements by the end of July.  They certainly won't
    make this date, but perhaps they will come close.

3) TORC:

    Short camera at TORC: S02 is 99% done.  Since this is a CaF2
    element, the other 1% could take months.  S05, S07, and S09
    are in polishing.  S03 is in grinding.

4) SAGEM/REOSC Short Camera Aspheres:

    SAGEM/REOSC pulled a classic bait-and-switch, getting us to
    sign a contract and then informing us that they could not
    produce interferograms of the final surfaces.  We don't think
    that this was intentional or fraudulent, but we do not intend
    to accept this.  Currently I do not understand why they
    cannot make interferograms, but I have proposed four ways to
    make the process easier anyway: using a less sensitive test,
    making the optics better than the minimum required, upgrading
    their interferometer, and measuring smaller sub-regions.

5) Johnson Filters:

    The design engineer in charge of the job at Barr quit.  I
    have not yet been able to contact his replacement.

6)  Gunn Filters: No progress.  I plan to thrash out the details
    with Ian next month.

7)  Grisms: waiting for astronomers to choose central wavelengths


	Electronics (Asa/Carr)

Asa:

Accomplished in July:

Shutter: Final testing completed.

Filter Server 2: Assembly 90% complete.

Center Field Guide Camera: Assembly complete, testing started.

Electronics: Mounting Panels completed. Chassis #2 started. Chassis #2
contains electronics for the Shack Hartman guide camera, the Principle
guide camera, and a yet to be determined mechanism.

To Accomplish in August:

Filter Server 2: Complete, test, and crate.

Electronics: Complete Chassis #2.

Guide Cameras: Test Center Field Guide Camera. Assemble Principle
Guide Camera.

Dewar: Specify motor driver for focus motor, continue design of focus
limits.

	Software (Birk/Clardy)

Birk:

1) Physik-Instrumente DC-motor controller: I wrote a library with
   routines to initialize (find reference point) and move the
   motors. The motors work fine and are very reliable.  The
   repeatability is better than 1 micro-meter.  I also created a
   test-GUI that allows each motor to be moved at variable speed and
   acceleration.

2) Physik Instrumente Piezo Controller: I wrote a library to move the
   piezo stage. A test-GUI allows to either set a voltage or an
   absolute position. The stage works well without any load. Adding
   the detector-mounting puts the stage into a wild vibrational
   motion. I contacted PI but have not received an answer yet.

3) Shutter-#1: Joe built a test setup for the shutter. The shutter was
   mounted to allow horizontal and vertical blade movements. A pulse
   generator created the open/close signal and we measured the open
   time depending on shutter orientation and input-pulse length.  We
   found a small (2ms) difference between up- and down-ward motion of
   the blades. The typical error in open-time versus pulse-length was
   2-3 ms. Since the error-budget (1% at 1sec) allows for a 10ms error
   we find that the shutter is working very well.

4) TCP/IP-serial hub: I started investigating the 'Comtrol' serial
   hub. There seem to be some small problems in the way the driver
   handles sporadic traffic but there may be ways to program around
   that. I am also looking at a similar product from another company
   (Equinox).

For August I plan to work on the center field guider, continue
the experiments with serial hub and write a library for the 
HP-data-acquisition unit (temperature, pressure, etc).

	Detector Systems (Thomson/Burley)

In July we worked mostly on understanding the system noise
characteristics of the new science electronics.  In August, Greg will be
on vacation, and I will be working on the mechanical part of the dewar,
including the CCD alignment for the 4Kx4K and IMACS arrays.

Greg also submitted second versions of a couple of boards for
manufacture (probably PCI, extender card and one other).

Jorge worked mostly on Magellan stuff, he'll be assembling PCI cards
in August, as well as helping with Magellan guider parts.

	Mechanics (Bigelow/Hare)

Bigelow:

In July:

1) Received most of collimator mechanics from M&T.
2) Received some LCAM mechanics from M&T
3) Received baffle materials for evaluation 
4) Completed thermal analysis for IMACS enclosure design
5) Completed design of guider/field-lens/SMS interface to structure
6) Received acceptable laser-cut slit masks from Laserdyne/Prima.
7) Completed test mounting of dummy C02 in reject C02 cell.
8) Completed design of CFG and long camera slit-mask baffles.

For August:

1) Out of the office 8/6 - 8/27
2) Mount C02 lens in cell
3) Receive revised mask cutter quotation from Laserdyne
4) Receive remaining collimator and long camera mechanics from M&T
5) Start design of modifications of SMS for CFG and long camera masks

Hare:

Current Work

* Final testing of shutter complete.  Test results show performance of
  shutter to better the goal of 1% linearity for a one second exposure.
* Updating the shutter drawing package and solid models in preparation
  for fabrication of second shutter
* The drawing packages for all guide cameras are now complete.
* Fabrication and assembly of the Center Field Guider is now complete.
  Testing of this subassembly is now in progress
* Fabrication of the both the Principal and Shack-Hartmann Guiders is
  near completion.
* Fabrication of Field Lens Ring Assembly is now complete, however
  minor rework is required due to the discovery of a small interference.
* Review of the design and drawing package for all sub-assemblies of
  the Disperser Server continues.
* Continue to provide assistance with structure design issues as
  necessary.
* Test lamps for Calibration Unit arrived and proved acceptable for
  use in final design.

Future Work

* Fabrication of the second shutter.
* Assembly and testing of all guide cameras.
* Continue revisions to solid models and part drawings of any subassembly 
  as needed.
* Examine coating tooling setup for Field Lens (from Cleveland Crystal)
* Have Field Lens Ring Assembly coated.  Expected delivery by August 10th.
* Review design of Disperser Server and continue work on the solid models.
* Order outstanding parts for disperser server sub-assemblies that are 
  currently in fabrication.
* Resume design work of the Calibration Unit.


	Fabrication (Kowal/Storts/Castillo/Ramirez)

Kowal:

1) Principle guider, minus barrels, is complete.
2) Shack Hartmann guider is near completion, minus a barrel and some assorted parts.
3) Disperser Sever fabrication was on hold this month.


Expectation's for August:

1) Finish all guider parts and modifications.
2) Produce a second shutter.
3) Finish uprights and base plate for grating tilt mechanism.
4) Programming and ordering for remainder of disperser server system.
5) If time permits, make additional grating cells and covers.

8)     Other Business

Next meeting:  10:15, 8/29/2001