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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 infrared camera for the Visible and Infrared Survey Telescope for Astronomy (VISTA) sets many technical challenges for mechanical and thermal design. The flexion between optical subsystems must be minimised to maintain alignment in various camera orientations and meet performance requirements. Thermally induced stresses, atmospheric pressure and earthquake loads place high demands on structural components, some of which must also thermally isolate the cold (~70 K) detectors and optics. The success of the design hinges on the optimisation of heat flow to minimise thermal loads on the detectors whilst holding external temperatures very close to ambient to reduce misting and convective disturbances in the field of view. This paper describes the mechanical and thermal components of the design and discusses the analyses in detail.

A LIPS monitor for real-time analysis of aqueous and other liquids has been developed. This system enables the laser to sample a fresh surface while preventing problems associated with the laser liquid interaction. We outline its successful laboratory and on-line industrial operation.

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.

Differential domain‐wall propagation in the surface layers and interior of single‐crystal c‐axis‐oriented 75‐μ‐thick Sm0.55 Tb0.45 FeO3 platelets has resulted from high surface coercivity induced by mechanical polishing. Cylindrical magnetic domains with measured wall coer‐civities of 0.5 Oe were formed inside the platelets following saturation of the surface magnetizations. The magnetized surfaces imposed a self‐biasing effect on the bubbles. These bubbles were propagated at 100 Hz with a Permalloy T‐bar shift register.

Unusual cylindrical magnetic bubble domains completely bounded by domain walls have been stabilized inside YbFe03 platelets with high surface coercivities. The energy density of the walls forming the cylinder ends manifests itself as an effective bias field, which, for platelet thicknesses between 55–75μ, stabilizes bubbles in zero applied field. Annealing at 700°C for one hour reduced the coercivity associated with bubble propagation to 0.25 Oe. A theoretical analysis of the stability and coercivity of these self‐biased bubbles is given.