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The VISTA IR Camera has now completed its detailed design phase and is on schedule for delivery to ESO's Cerro Paranal Observatory in 2006. The camera consists of 16 Raytheon VIRGO 2048×2048 HgCdTe arrays in a sparse focal plane sampling a 1.65 degree field of view. A 1.4m diameter filter wheel provides slots for 7 distinct science filters, each comprising 16 individual filter panes. The camera also provides autoguiding and curvature sensing information for the VISTA telescope, and relies on tight tolerancing to meet the demanding requirements of the f/1 telescope design. The VISTA IR camera is unusual in that it contains no cold pupil-stop, but rather relies on a series of nested cold baffles to constrain the light reaching the focal plane to the science beam. In this paper we present a complete overview of the status of the final IR Camera design, its interaction with the VISTA telescope, and a summary of the predicted performance of the system.

As detailed instrument design progresses, judgements have to be made as to what changes to allow and when models such as thermal, stray-light and mechanical structure analysis have to be re-run. Starting from a well-founded preliminary design, and using good engineering design when incorporating changes, the design detailing and re-run of the models should bring no surprises. Nevertheless there are issues for maintaining the design and model configuration to a reasonably concurrent level. Using modern modeling software packages and foresight in setting up the models the process is made efficient, but at the same time the level of detail and number of cases now needed for instrument reviews is also large in order to minimise risks. We describe examples from the detailed instrument design of the VISTA IR Camera to illustrate these aspects and outline the design and analysis methods used.

The Production Location Analysis NETwork System (PLANETS) was developed to provide General Motors with the capability to evaluate complex quantifiable business decisions. Originally implemented in 1974, PLANETS has evolved into a flexible framework for scenario description and analysis. It is now supported by Electronic Data Systems Corporation. Individuals with no prior computer or mathematical programming background use PLANETS to decide what products to produce; when, where, and how to make these products; which markets to pursue; and which resources to use. PLANETS also provides detailed shipping allocations and capital spending schedules. PLANETS' worldwide use throughout General Motors has contributed to the understanding of business problems. Usage of PLANETS in-site selection and tooling allocation studies has resulted in substantial cost avoidance.