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Introduction of an array of new electrical and electronic features into future vehicles is generating vehicle electrical power requirements that exceed the capabilities of today's 14 volt electrical systems. In the near term (5 to 10 years), the existing 14V system will be marginally capable of supporting the expected additional loads with escalating costs for the associated charging system. However, significant increases in vehicle functional content are expected as future requirements to meet longer-term (beyond 10 years) needs in the areas of emission control, fuel economy, safety, and passenger comfort. A higher voltage electrical system will be required to meet these future requirements. This paper explores the functional needs that will mandate a higher voltage system and the benefits derivable from its implementation.

The need to substantially reduce the weight of automobiles to improve performance or meet CAFE requirements has led to an increased use of lightweight materials such as aluminum. To use aluminum efficiently in auto body structures, component and joint designs and joining methods are likely to differ from those traditionally used in steel bodies. With proper design, aluminum automotive frames can efficiently meet or exceed the performance requirements for stiffness, static strength, fatigue strength and crash performance. This paper presents some joint design concepts for aluminum frames and compares the performance of joining methods such as resistance spot welding (RSW), gas metal arc (GMA) welding, weld bonding, adhesive bonding, riveting and mechanical clinching for both unibody and spaceframe construction. Recommendations for preferred joining methods are also made based on the effect of design details on joint performance and assembly.

Societal demands for greater automotive fuel economy, lower environmental impact and improved performance have produced a trend towards lightweighting in automobiles. In this context, the effect of car mass and size on occupant safety is receiving considerable attention in the literature. Concerns have been raised about the safety of occupants of smaller, lighter cars involved in accidents with larger, heavier vehicles. The evidence supporting these concerns comes from crash data of existing steel-bodied cars. In this paper, the possibility of using an aluminum body structure to reduce automobile mass is explored. The use of lightweight aluminum provides the opportunity for a larger low mass structure than could be achieved by traditional steel body construction. This paper provides technical data related to the energy-absorbing characteristics of aluminum components.

For efficient, flexible, and high-quality checkout, the capabilities and limitations of checkout equipment must be considered in the spacecraft design. Ideally, spacecraft and GSE should be designed as a working entity, with ground rules established for their concurrent development. Emphasis must be placed on systems engineering to establish and maintain compatibility. Some insight into the importance of GSE in meeting space objectives is presented together with an analysis of the degree to which spacecraft design is influenced by GSE.

The requirements for on-board checkout for advanced space missions are identified and an on-board checkout system capable of meeting the requirements is defined. The development of a major hardware element of the defined system is discussed. Application of advanced design technology to the developed hardware has permitted substantial capability to be incorporated on board advanced mission vehicles with very little weight, volume and power consumption penalty. The on-board checkout system software development and application are described.

Multigrade motor oils formulated to meet both Ordnance Supplement 1 and API service “MS” requirements were subjected to over three million miles of heavy-duty field tests. Engine wear and oil consumption were equal to, or lower than, results obtained with single-grade oils in similar service. Trucks, buses, and tractors favor multigrade oils over single-grade oils in engine starting at low temperatures and in fuel economy. Well-formulated multigrade oils also extend the period between engine overhauls and decrease inventory requirements. The savings realized in fuel economy and ease of starting far outweigh the additional cost of multigrade oils. Properly blended multigrade oils give an additional bonus in engine life. These results are dispelling the reservations held by some engine builders and fleet operators concerning multigrade oils.