Instrument panel case study

Texture on a nylon 6 moulding, due to spark erosion (top) or photo-etching (lower) mould sur ces (from Schauf D, ATI 584e, booklet, Bayer Material Science AG, 1988). 

Federal Motor Vehicle Standard FMVSS 201 requires that a 4.5 kg head-form is fired at 15 mph at any interior region that could be hit by the head of an unbelted vehicle occupant. There is a triaxial accelerometer inside the 

FEA of head-form impact on a) an instrument panel (Silk, G., SAE Technical Paper 2002-01 -1270 Haque et al SAE Paper 2000-01-0624 for an impact b) a ribbed moulding at the top of an p added A pillar SAE International. 

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The case study described here concerns a human factors audit of a computer controlled process system which was being introduced in a distillation imit of a chemical plant. The unit was in transition from replacing its pneumatic panel instrumentation with the new system. However, control had not yet been transferred and the staff were still using the panel instrumentation. The role of the project was to evaluate a preliminary design of the computer-based display system and provide recommendations for future development. 

In mathematical optimization for many applications, it is commonly expected that the response surface will have a bell shape for which the point located at the top of the surface can be picked as the optimum point without any debate. However, in the case study of this paper, such a response surface was not obtained. Other engineering criteria were applied as a compromise between pros and cons, according to implications revealed by the response surfaces. Cross-checking the optimization result based on instrumental measured quantities with that from panel studies is important for validation. Although it is a powerful optimization tool with versatile applications, without professional knowledge and experience, the contribution of RSM is limited. 

The barometric setting provided by the flight crew on the Display Control Panel is not relevant for pressure altitude, and it is therefore not considered further in this case study. Other elements of the upgraded system, such as the Standby Flight Instrument and Inertial Reference System (IRS), are also not considered in this case study. 

The methods discussed earlier are applied to the seat-occupant-restraint system of an aircraft. A description of a computer-aided analysis environment, including a multibody model of the occupant and a nonlinear finite element model of the seat, is provided, which can be used to re-construct variety of crash scenarios. These detailed models are useful in studies of the potential human injuries in a crash environment, injuries to the head, the upper spinal column, and the lumbar area, and also structural behavior of the seat. The problem of reducing head injuries to an occupant in case of a head contact with the surroundings (bulkhead, interior walls, or instrument panels), is then considered. The head impact scenario is re-constructed using a nonlinear visco-elastic type contact force model. A measure of the optimal values for the bulkhead compliance and displacement requirements is obtained in order to keep the possibility of a head injury as little as possible. This information could in turn be used in the selection of suitable materials for the bulkhead, instrument panels, or interior walls of an aircraft. The developed analysis tool also allows aircraft designers/engineers to simulate a variety of crash events in order to obtain information on mechanisms of crash protection, designs of seats and safety features, and biodynamic responses of the occupants as related to possible injuries. 

Continuous scans of modulus versus temperature utilizing the DuPont Dynamic Mechanical Analyzer (DMA) has provided a comparison of the high temperature service capabilities of radiation-cured experimental formulations of a vinyl-modified epoxy resin. Shell Epocryl-12. These scans were compared to data obtained when the same materials were applied as adhesives on aluminum test panels, radiation-cured with an electron beam, and lap shear strength tested at discrete temperatures. The DMA instrument utilizes a thin rectangular specimen for the analysis, so specimens can be cut from blocks or from flat sheets. In this case the specimens were cured as sheets of resin-saturated graphite-fibers. The same order of high temperature stability was obtained by each method. However, the DMA method provided a more complete characterization of temperature performance in a much shorter test time and thus, it can be very useful for quick analyses of formulation and processing variables in many types of materials optimization studies. The paper will present details of this study with illustrations of the comparisons. 

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