IMACS progress report no. 15 B. Bigelow 30 June 1999 Mechanics Objectives for June: Status: I.P. A. Continue mask cutting development (BB) I.P. B. Continue mask server detail design (BB) Done C. Complete filter server prototype design (TB/MP) I.P. D. Start filter server final design (TB) I.P. E. Start searches for mech. eng. and machinist (BB) Done F. Finalize l-cam and coll. mech. design plans (BB/TB) Done G. Complete dewar mech. design (Luppino) I.P. H. Start dewar prototype fabrication (Luppino) Done I. Order Physik Instrument (PI) flexure control stage (BB) Mechanics Objectives for July: A. Continue mask cutting development (BB) B. Continue mask server detail design (BB) C. Continue filter server final design (TB) D. Start fabrication of filter server prototypes (TB) E. Continue engineer and machinist recruitments (AD/BB/TB) F. Continue dewar prototype fabrication (Luppino) I) Project scope, budget, and schedule After careful consideration of several consultants, we have decided to keep the mechanical design of the optics mounts (cameras and collimator) "in house", rather than contracting for them. In order to keep to the current schedule, we will be hiring an additional mechanical engineer to share the extra design work with Tim and Bruce. Interviews of two candidate mechanical design engineers were conducted in June. References are currently being checked, and an offer could be made in July. An IMACS project meeting was held on June 22nd. Action items from the meeting included: a) Brian to continue coatings comparisons, and to look into pushing the dielectric coating curves closer to the sol-gel curves (July). b) Alan to work with Christoph on layout of instrument status database (July). c) Bruce to check with Dave Carr about prototyping the instrument motion controls for the filter server mechanism (Done). d) Ken and Alan to firm up guide camera positioning specifications in July (July). e) Alan to work with Gus and Ian on electronics space for IMACS (Done). f) The next IMACS project meeting will be held on Thursday, July 29th, at 11:00 in the new conference room. The recruitment of a machinist/instrument builder for IMACS was delayed by Observatory planning regarding machinists and management of the machine shop. However, we have been authorized to hire a new machinist specifically for IMACS, and the recruitment for that position will start in July. Mary Poteete, our contract drafter, has started work on the prototype parts for the filter changing mechanisms. So far, exchanging files via the internet is working fine. II) Mechanics Bruce: Slit mask fabrication development continued in June. We received additional carbon fiber (CF) samples in June, and now have CF samples which have been cut to spec. with a laser at Laserod (LA). This effort is running late, but is not impacting the project schedule at this point. Laser cutting of the aluminum samples was not quite to spec, and we will be continuing the testing on 0.020" aluminum in July. Ultimately, we hope to be able to demonstrate acceptable laser slit cutting in aluminum as well. We are having two more masks in 0.032" and 0.020" spun by Ace Metal Spinning, and should be able to evaluate those by the end of July. As the carbon fiber material is still the most promising, I will be looking for an affordable source for fabrication of the full size masks in CF in July. Detailed design of the Slit Mask Server (SMS) continued in June and is on schedule for completion in October. Preliminary designs for the full-field slit mask assemblies, the mask cassette, cassette shuttle, and extraction mechanism are all complete. Design of the mask transfer mechanism and mask position sensing components should be completed in July. Tim: The solid models for the filter server slide mechanism were completed and sent to Mary Poteete for detailing. This turned out to be a very constructive exercise, as it helped to establish our drawing tree structure, and served as a good trial run for some of the larger drawing packages that we are planning to send to Mary. Very soon we should have several items that we can begin to push through the shop. Work on the rest of the filter server mechanism has continued. It is anticipated that the filter mechanism design effort will be done on schedule (mid August) with a very good possibility of being completed ahead of schedule. On Wed July 9/99, several members of OCIW (Bruce, Brian, Allen, and Tim) attended a meeting with OPTICS 1 (Westlake Village) in order to determine their ability to handle the work on the optomechanical portion of IMACS. It was decided that we will keep the optomechanical design effort here at OCIW, and that OPTICS 1 would be an excellent candidate to pick up some of the work after the engineering portion is completed (i.e. fabrication and assembly). It was decided that with the addition of another Mechanical Engineer, there are no ramifications with respect to the present schedule in keeping all of the optomechanical design effort here at OCIW. III) Electronics We are planning to operate the filter server mechanism under computer control by the end of 1999. Dave Carr plans to provide the electronic design for the filter server system in time for operation of the motion stages. IV) Software Christoph: 1) a 1st version of the IMACS (mechanical) GUI is ready as a baseline for discussion. 2) started with the networked (TCP/IP) database. V) Optics Brian: DONE, June: 1) All of the Ohara glass has arrived. Harland will start on the melt re-balance for both the long and short camera this month. The two cameras must be done together in case the curve on the dewar window changes. 2) After some iteration, the coating designs from Coherent are now relatively stationary. A preliminary theoretical model of Sol-Gel is comparable, except that the dielectric coatings are flat across the passband while the Sol-Gel is peaked at 0.55 microns. I have obtained actual Sol-Gel measurements from Harland, and will mock up a better model for comparison. 3) The sensitivity analysis for the individual optics was re-done with considerably more accuracy than previous versions. The collimator requires 0.001" tolerances, but the long camera is considerably tighter. 4) The direct imaging mirror has been coated. There is some green stuff on it that needs to be explored. ------------------------------------------------------------------- TODO, July: 1) Baffle analysis 2) Make some decisions about coatings 3) Order glass for a test cell 4) Order test gratings for protected coating tests 5) Prod Optovac about CaF2 VI) Detector Systems Greg/Ian: Detector systems progress (June 1999) ==================================== 1 - revised circuit board layouts have been sent for fabrication for the DSP timing board, signal processing board, power supply board, and the clock driver board. 2 - for the low temperature test of the guider camera, we have put together the CCD housing, installed the TE cooler and temperature sensor, and acquired a recirculating pump + bucket. 3 - GB started the layout of the DSP board for the mosaic camera. 4 - we are awaiting the arrival of the bare PCI interface boards for our summer student to start assembling next week.