IMACS progress report no. 6 B. Bigelow 1 October 1998 Objectives for September: Status: I.P. A. Continue slit mask fabrication development Delayed B. Start fabrication of a full scale mechanical instrument model I.P. C. Start dewar and CCD array design/fab devel. (contract) I.P. D. Start TV guider design/fab devel. (contract) I.P. E. Start disperser server design/fab devel. (contract) Done F. Prepare for new engineer start (10/5/98) Done G. Order Cryotiger closed cycle cooler for testing (for CCD mosaic) Objectives for October: A. Continue slit mask fabrication development (Bruce) B. Let dewar/flexure control design contract (Bruce) C. Continue TV guider design and layout (Brian/Bruce/Tim) D. Start prelim. design of slit masks and frames (Bruce) E. Start prelim. design of disperser server (Tim) F. Start prelim. design of shutter (Cons.) G. See GMOS laser cutter system acceptance testing Optics and CCD reports from Brian Sutin and Greg Burley attached. 1) Project scope, budget, and schedule A detailed performance specification was completed this month for the disperser server system. Two consulting groups were interviewed in Victoria for possible design of the server. However, our new project mechanical engineer, Tim Bond, wants to do the design instead. Bruce and Tim divided the IMACS design tasks during the DAO visit, which will require a minor reorganization of the project schedule. Gerry Luppino, of GL Scientific, has bid on the mechanical design and fabrication of the dewar and flexure control system for IMACS. His bid of $140,000 was somewhat higher than the original budget estimate of $110,000. Bruce, Ian, and Greg will be reviewing the bid next week, and hopefully letting a first design contract this month. Bruce and Alan visited the instrument group at DAO in Sept. We saw the slit mask handling system for GMOS, parts of the on-instrument wavefront sensor, and parts of the collimator and camera cells (Tim's work). We also saw a very simple and robust system for applying sol-gel coatings on optics up to 30" in diameter. Using sol-gel on some of the IMACS optics has the potential to save large amounts of our $265K coating budget. Finally, we also saw another dewar cooled with a APD Cryotiger closed-cycle cooler, of the same type we ordered for testing for IMACS. 2) Mechanical Engineer recruitment Tim Bond will be starting officially on 10/5/98, but making his first appearance on 10/2/98. He will be in the office between Eric Persson and Ken Clardy. A NT PC and AutoCAD/Mech. Desktop have been ordered for Tim, and both are due 10/9/98. 3) Conceptual designs Steve Gunnels will be modifying his preliminary structure design and FEA this month, in order to enable a closer comparison of the monocoque and space frame structures for IMACS. Bruce attended a training course for Mechanical Desktop, the 3D design and drafting tool we will be using for IMACS. Tim is already an experience user of the software. 4) Slit masks and fabrication The GMOS laser mask cutter is nearing completion at ART in San Diego, and should be done by the middle of this month. A visit to see the machine in action will be scheduled once it is fully operational. Another quote for slit mask blanks came in this month at $283/ea for 1000 masks; this is more than twice the cost of the first quote. Two more quotes are expected this month. 5) Instrument model Construction of the model was planned a bit prematurely, and will be delayed until we have a better picture of the instrument structure in hand. Smaller models of optics, etc. may be made sooner. 6) Electronics No electronics progress scheduled or completed this month. 7) Software No software progress scheduled or completed this month. 8) Optics Via Brian Sutin: I did a preliminary layout of the TV system. The long-slit viewer no longer hangs out in front of the instrument, which I consider a major improvement. Instead, the long-slit is tilted 45 degrees, directing the light off to the side. No one has come up with any major objections to this plan thus far. The Magellan Telescope designs for the viewers at the edge of the field are more advanced that those for IMACS, and as the telescope and IMACS guiders should be made as similar as possible, IMACS will probably steal many of the details. RFQ's for fabricating the field lens were sent out to five manufacturers. So far we have received one no-bid and two bids considerably higher than the estimated cost ($50K). The remaining two manufacturers are not returning phone calls. RFQ's for the fabrication of the remaining lenses in the collimator and field lens have been sent out to seven manufacturers. One grating (the 600 lines/mm blazed for 5000A) has been ordered. The direct-imaging flat has been sized (200mm diameter x 35mm). The thermal analysis is about halfway done. The only partial result is the fact that if the dndt's are applied for a 0-20C range of temperatures, the focus moves by about 1 mm. CTE changes could double or reverse the focus motion. TODO, October: 1) Try to wind up the Field Lens RFP in some affordable way. 2) Order material for the direct imaging flat. 3) Finish thermal analysis. 4) Get scale from Lick (I hope), and begin checking Ohara blanks for correct size and density as they arrive. 5) Fill in more of the TV guider details. Late breaking news: UPS smashed the $10,000 fused silica blank when it was being shipped from the edging company to Dynasil. Sad, although it isn't our problem, and will cause no delays for us. 9) Guiders and CCDs Via Greg Burley: Here's the latest progress on the guider camera (for Sept): 1 - the prototype housing is out of the shop, ready to be populated with circuit boards. At the moment, the backplane board and power board are installed. Other boards are waiting for a small number of parts to arrive. 2 - first pass of the linux device driver for the PC interface. It loads. It unloads. It reads and writes configuration registers. Next up -- read() and write() routines. And, the latest progress on the mosaic camera (for Sept): 1 - Ian and Greg have come up with a design concept for the basic array system electronics that will work for the 8k x 8k mosaic, and scale gracefully to other sizes (such as a single chip 2k x 4k, or a two-chip 4k x 4k mosaic). (a) six circuit boards for the 8K x 8K mosaic outside the dewar [dsp+timing(1), signal_processing(2), clock_driver(2), power+utility(1)]. (b) two flex-circuit boards inside the dewar for preamps, and clock buffers (c) standard VME/Eurocard 6U card size (6.2 x 9.2 inch) (d) four signal processing channels per card, using the Analogic ADC4320 A/D converter 2 - drawing of the schematics is well under way. Version 0.1 will be available soon. 3 - Bruce has put a Crytotiger on order -- delivery in October. 4 - Request for quote to Luppino sent out.