IMACS progress report no. 5 B. Bigelow 3 September 1998 Objectives for August: Status: Postp. A. Continue preparations for design review to occur in late Sept. Done B. Complete recruitment for a mechanical engineer Done C. Complete instrument structure concept development I.P. D. Continue slit mask fabrication development I.P. E. Begin fabrication of a full scale mechanical instrument model Done F. Distribute first version of the current project schedule Objectives for September: A. Continue slit mask fabrication development B. Start fabrication of a full scale mechanical instrument model C. Start dewar and CCD array design/fab devel. (contract) D. Start TV guider design/fab devel. (contract) E. Start disperser server design/fab devel. (contract) F. Prepare for new engineer start (10/5/98) G. Order Cryotiger closed cycle cooler for testing (for CCD mosaic) 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 CCD array. The CCD spec. is part of the process for contracting parts of the CCD mosaic support and cryostat, possibly to the UH detector lab. The current project schedule was distributed to project members at the end of August. Let me know if you would like a copy. 2) Design Reviews The preliminary design review has been rescheduled for Jan. 1999. An internal conceptual design review (CoDR) was held at OCIW in July. Rather than hold a second, external review of the current concepts, we will complete the preliminary design phase, and then hold an PDR (preliminary design review). Dan Fabricant (SAO) and Matt Radovan (UCO/Lick) have agreed to serve as external reviewers. 3) Mechanical Engineer recruitment Tim Bond, previously a mechanical design engineer at DAO, formally accepted our offer on 8/26/98. He will be starting at OCIW on 10/5/98. Tim has been working on structures, opto-mechanics and lens mounts for Gemini Multi-Object Spectrograph (GMOS) and the Gemini AO system. He brings an ideal combination of training and experience to our project and we look forward to his arrival! 4) Conceptual designs Preliminary finite element analysis (FEA) of a space-frame structure for IMACS was completed in August, and a short report was prepared. The initial concept uses a steel weldment optical support structure (OSS) to join the cameras, collimator, and disperser server, and trusses to attach optics to the OSS and the OSS to the telescope. The FEA showed that although the first-cut design does not meet our 0.1 pixel spec. for flexure, the worst-case flexures of 0.4 pixel (0.044 arcsec. long cam.) may be improved in the final design, and are easily corrected with small translations of the CCD array (flexure control). 5) Slit masks and fabrication Leads were obtained from the GMOS project for a composite fabricator, Kinetic Composites (KE), and a laser-cutter manufacturer, Advanced Recording Technologies (ART). ART has quoted $177K for a laser-based slit mask cutting system for IMACS. A quote from KE for $115 per mask in quantities of 1000 was higher than expected, and additional requests for quotation (RFQ) will be sent out. 6) Instrument model Tools and materials have been ordered for model building, but actual construction of the model has not started. 7) Electronics No electronics progress scheduled or completed this month. 8) Software No software progress scheduled or completed this month. 9) Optics Via Brian Sutin: Optical Report for August, 1998 1) Ohara glass for the short camera has been ordered. 2) RFQ's have been submitted for all of the fused silica. The quotes were returned, with Dynasil coming in as low bidder by a factor of 4 in price. The fused silica order has been placed with Dynasil. 3) RFP's have been submitted to four possible fabricators for the field lens. One other possible fabricator (Raytheon) has not been reachable. 4) Some preliminary design has been done on the TV systems. All three TV guiders will most likely have a field lens cemented onto a right- angle prism or mirror/lens combination. The light will then be imaged by either an achromat or a 35mm macro lens. TODO List for September: 1) RFP for collimator & long camera fabrication 2) Thermal analysis 3) More TV guider design 4) Order gratings 10) Guiders and CCDs Via Greg Burley: Here's the latest progress on the guider camera (for August): 1 - we've started to populate the circuit boards. Parts continue to trickle in. Two copies of the Power Circuit Board have been populated, run through the surface-mount oven (thanks Alan B) and (almost) finished off with through-hole components. The whole surface mounting/reflow_oven process is quite interesting to watch and I hope you all get a chance to see it as we make the next boards. 2 - the housing is currently in the shop and is starting to take recognizable form. The parts are set to be dip-brazed into one unit soon. 3 - updated schematics and Guider Camera Design Description v0.2 are now available. 4 - first pass on the design of the PCI interface. Mostly it consists of a FIFO, a programmable logic chip and some line drivers/receivers. Parts are on order. The prototype will be a breadboard that plugs into a development kit card that we have in hand. 6 - we received an update of Altera's MAX-PLUS II design software (gratis) to allow us to design and program the programmable logic. The actual programming cable is on order. And, the latest progress on the mosaic camera (for August): 1 - Bruce, Ian and Greg met with Gerry Luppino in his lab at UH to look at the GL technique for building mosaics. There are quite a few aspects of the design that we think we should do in a similar way, including: (a) mount each CCD on a "boat" or shim which has a machinable/grindable three point mount to take out tip/tilt of each individual device. One innovation we may make here is to add alignment pins to the boat and alignment holes to the chip carrier plate (ie attempt to align the CCD columns over the whole composite mosiac device). (b) attach heaters and cooling straps from the cold surface to the individual CCD boats (c) use flex circuits to simplify the task of wiring the inside the dewar. The GL design was very clean, and had no active components. We would consider putting the preamps and clock buffers inside the dewar. 2 - Bruce, Ian, Greg and Charlie met with the rep from CryoTiger. We propose to investigate whether we could use a dual CryoTiger to replace the traditional LN2. 3 - continued work on the schematics and draft documentation for the mosaic.