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This report addresses the technical challenges engineers must face, including the issues of storage devices, generation of the 42 volts, and distribution of power. It contains information on all of the critical aspects related to the adoption of this technology.

Development of higher-voltage electrical systems in vehicles has been slowly progressing over the past few decades. However, tightening vehicle efficiency and emissions regulations and increasing demand for onboard electrical power means that higher voltages, in the form of supplemental 48 V subsystems, may soon be nearing production as the most cost-effective way to meet regulations. The displacement of high-wattage loads to more efficient 48 V networks is expected to be the next step in the development of a new generation of mild hybrid vehicles. In addition to improved fuel economy and reduced emissions, 48 V systems could potentially save costs on new electrical features and help better address the emerging needs of future drivers. Challenges to 48 V system implementation remain, leading to discussions by experts from leading car makers and suppliers on the need for an international 48 V standard. Initial steps toward a proposed standard have already been taken.

Linear displacement transducers may be used to measure deflection and, based on time histories, calculate rates of deflection and viscous criterion (VC). The current study documents that these transducers are subject to damage affecting the linearity of their responses, that this damage is not uncommon, and that the deviations from linearity can greatly affect calculations of deflection rate and VC. A calibration procedure to identify transducers with significantly non-linear responses is proposed.

A key topic of many technical discussions has been the development of alternative fuels to power the compression ignition engine. Reasons for this include the desire to reduce the dependency on petroleum-based fuel and, at the same time, to reduce the particulate matter (PM) and NOx emissions. Also, there has been interest generated in the diesel engine because of the reduction in greenhouse gases that has been proposed during the 2008-2012 time frame in Europe and the regulations that affect diesel engines in the United States.

This study, which is an extension of an earlier study, examined an additional 64 frontal crashes of airbag-equipped vehicles in the 1997-98 National Automotive Sampling System Crashworthiness Data System (NASS/CDS) in which the driver died. The principal cause of death in each case was determined based on an examination of the publicly available case materials, which primarily consisted of the crash narrative, the injury/source summary, and photographs of the crashed vehicle. Results were consistent with the earlier analyses of the 1990-96 NASS/CDS files. In the combined data set (1990-98), gross deformation of the occupant compartment was the leading cause (42 percent) of driver deaths in these 116 frontal crashes. The force of the deploying airbag (16 percent) and ejection from the vehicle (13 percent) also accounted for significant portions of the driver deaths in these frontal crashes. There continues to be little or no evidence that airbags deploy with too little energy.

Using pressure sensitive adhesive tapes to achieve economy and efficiency in automotive assembly

The Insurance Institute for Highway Safety (IIHS) evaluates autonomous emergency braking (AEB) systems as part of its front crash prevention (FCP) ratings. To prepare the test vehicles' brakes, each vehicle must have 200 miles on the odometer and be subjected to the abbreviated brake burnish procedure of Federal Motor Vehicle Safety Standard (FMVSS) 126. Other organizations conducting AEB testing follow the more extensive burnishing procedure described in FMVSS 135; Light Vehicle Brake Systems. This study compares the effects on AEB performance of the two burnishing procedures using seven 2014 model year vehicles. Six of the vehicles achieved maximum AEB speed reductions after 60 or fewer FMVSS 135 stops. After braking performance stabilized, the Mercedes ML350, BMW 328i, and Volvo S80 showed increased speed reductions compared with stops using brand new brake components.

Alyson Lyon, executive leadership coach, discusses the value of effective and efficient communication. SAE Members can view the full version by logging into the Member Connection. Not a Member? Join us today at sae.org/join.

Alyson Lyon, executive leadership coach, discusses the value of being a mentor and/or a mentee. SAE Members can view the full version by logging into the Member Connection. Not a Member? Join us today at sae.org/join.

Alyson Lyon, Executive Leadership Coach, explains what stress is, and how to handle personally and professionally. SAE Members can view the full version by logging into the Member Connection. Not a Member? Join us today at sae.org/join.

The Insurance Institute for Highway Safety (IIHS) has been conducting frontal offset crash tests of new passenger vehicles and providing comparative crashworthiness information to the public since 1995. This program has resulted in large improvements in frontal crashworthiness largely because vehicle structures have been redesigned to prevent significant collapse of the occupant compartment. In late 2002, IIHS began a side impact crash test program in which the side-impacting barrier has been designed to simulate the geometry of the front ends of SUVs and pickups, which pose a much larger threat in side impacts than the lower front ends of cars. It is anticipated that this program, too, will result in changes in vehicle structure, in this case the structure of the vehicle side pillars and door hardware. Good performance in the side impact test also is likely to require installation of side airbags (or comparable system) to protect the head and/or chest.

The pace of replacement of petroleum-based fuels as the primary fuel supply for transportation may still be a point of debate. However, the need to find a viable replacement fuel or group of fuels is no longer a major point of debate. The panel will outline what has changed on the journey during the past few years and what the future holds. Viewpoints from government, the military, fuel suppliers and academia will be presented.

This compendium presents the most complete design and engineering story available anywhere about this groundbreaking new vehicle. It also introduces you to the engineering team and how they made the world’s first production extended-range electric vehicle a reality. Combining articles from SAE International’s Vehicle Electrification and Automotive Engineering International magazines, new SAE technical papers, and all-new content, this full-color book is the only one of its kind that lifts the veil on how the GM team and key supplier partners met the difficult engineering challenges faced in developing the Volt. Topics include the Volt’s systems, components, and model-based design; a behind-the-wheel look at a Volt prototype; and how the Volt’s engineering team used OnStar to collect test drive data from preproduction Volt vehicles.

The Insurance Institute for Highway Safety installed a variety of infant, toddler, and booster restraints in vehicles subjected to high-speed frontal offset crash tests to assess the effects of severe crashes on the structural integrity of the restraints and their associated hardware (harnesses, buckles, clips, etc.). The child restraints were inspected before and after each test, and all damage was recorded. In some of the tests, forces and accelerations were recorded on the appropriate size child dummy properly secured in the child restraint. After a single severe crash, most restraints had sustained some damage, albeit minimal. Repeated tests indicated that these child restraints could withstand the forces of an additional crash with only minor additional damage. Dummy injury results suggest that current injury risk curves overstate the risk of neck injury to most properly restrained children.

The Insurance Institute for Highway Safety (IIHS) has recently developed and evaluated a new side impact barrier to represent the front profile of pickup trucks and sport utility vehicles for a new consumer information program. In the development of this program, two dummies were considered for assessing driver injury risk in side-struck vehicles: EuroSID-2 (50th percentile male dummy) and SID-IIs (5th percentile female dummy). The purpose of this study was to compare injury responses and kinematics for these two dummies in side impact crash tests. The findings suggest that SID-IIs will be more effective in driving relevant improvements in side impact crash protection.

The Insurance Institute for Highway Safety (IIHS) is investigating small overlap crash test procedures for a possible consumer information program. Analysis of real-world small overlap crashes found a strong relationship between serious head and chest injuries and occupant compartment intrusion. The main sources of serious head injuries were from the A-pillar, dash panel, or door structure, suggesting head trajectories forward and outboard possibly bypassing the airbag. Chest injuries mainly were from steering wheel intrusion and seat belt loading. In developing this program, two test dummies were evaluated for predicting occupant injury risk: midsize male Hybrid III and THOR. In the collinear small overlap crash tests conducted here, results from the two dummies were similar. Both predicted a low risk of injury to the head and chest and sometimes a high risk of injury to the lower extremities. Head and torso kinematics also were similar between dummies.

The concepts of “cost-benefit” and “cost-effectiveness” are increasingly cropping up in debate over present and future motor vehicle standards. Often they are introduced to attack, or justify, a particular standard. Just as often, they are misunderstood and misused. Since a motor vehicle safety performance standard has no costs per se, it cannot be evaluated either in cost-benefit or cost-effectiveness terms. It is the particular design alternatives available to manufacturers to achieve the objectives of a standard that have societal costs. The various design alternatives can be evaluated. Cost-effective designs should be chosen to minimize societal costs, and until there is evidence that cost-effective designs have been chosen, cost-benefit studies are premature.

Despite extensive media coverage to the contrary, mismatches among cars, utility vehicles, and pickups in crashes is not a big problem from a societal perspective. On the other hand, if you are riding in a small car that is about to be hit by a big utility vehicle, then the problem looms large. Crash compatibility has attracted a lot of attention lately because utility vehicles have become so popular. The concern is that their designs pose a threat to people riding in smaller cars. But the fact is, two-vehicle collisions between cars (including passenger vans) and utility vehicles or pickups account for only about 15 percent of all car occupant deaths. As a result, countermeasures that focus on making utility vehicles and pickups more crash compatible, however appropriate, can have only small effects on crash injuries and fatalities. On the other hand, improvements in crashworthiness not only reduce crash incompatibilities but also protect across a wider spectrum of crashes.

A BioRID (biofidelic rear impact dummy) representing a 50th percentile adult male was seated in the front passenger seat of six new vehicle models in a series of low-speed crash tests. The neck injury criterion (NIC) and other dummy responses that may indicate whiplash injury risk were recorded. Both front-into- rear and rear-into-barrier tests with an average velocity change of 11 km/h were conducted. Head restraints were tested in both adjusted (up) and unadjusted (down) positions. Damage to all models was minor, and longitudinal vehicle accelerations were low (less than 7 g). Neck extension angles and bending moments were much less than injury assessment reference values (IARV) (80 degrees and 57 Nm, respectively), indicating low risk of hyperextension injuries. Neck tension and transverse forces also were less than IARVs used to indicate the risk of more serious neck injuries.