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Successful development of a product requires the consideration and balancing of many design parameters. Proposals to modify designs that have been fully implemented and put into production are often made by people who were not involved in the original design process. Such proposals, commonly focusing on a specific aspect of the product, must be evaluated in the context of the overall product and its intended use by consumers; a design change may improve performance in one area but compromise performance in another, or even introduce new problem areas. As a case in point, several proposals have been made for operator protection systems with the claim that they would reduce the frequency and severity of injuries associated with All Terrain Vehicle (ATV) operation. For example, Johnson, Carpenter, Wright & Nelson (1991) considered selected accident modes and proposed a set of design changes involving a rollover protection system (ROPS) and significant vehicle modifications.

As reported by Wright and Carpenter (1) and others, the number of accidents resulting in serious injuries and deaths associated with All Terrain Vehicle (ATV) use increased dramatically during the 1980s. It was decided that a safer, more stable ATV should be and could be built. Three-wheel and four-wheel ATVs were considered. Two three-wheel ATVs and a four-wheel ATV were modified and fabricated as prototypes. While improvements of the three-wheel ATVs were realized, there were still considerable stability problems that could not be sufficiently corrected. The four-wheel prototype, denoted as RCX 250 (roll cage experimental vehicle with a 250 cc engine), demonstrated feasibility with clear improvements in safety. Analysis of the dynamics of the RCX 250 along with the description of the features and the test results are discussed.

Injury reconstruction is a process of injury analysis which combines both medical and engineering technology to produce a composite picture of injury causation. The process is outlined and the potential applications of this analysis are detailed.

A method is proposed for simulating the effects of dimensional variation from geometric dimensioning and tolerancing (GD&T) specifications. The method converts GD&T specifications into equivalent covariance matrices which are needed in the statistical simulation of random processes. Examples are given to show how the method can be implemented.

The last few years have witnessed a steadily increasing growth in the sales and use of three and four wheel all-terrain recreational vehicles (ATVs). These vehicles are promoted for off-road use and are operated in widely varied environments ranging from dry desert surfaces to wet hilly wooded areas of the country. The design of the ATV and its intended purpose make it an attractive vehicle for a large cross-section of the general public. The general appearance of the vehicle suggests a relatively simple and safe means of transportation, even in environments which have heretofore had limited accessibility. However, it appears that the design and operational characteristics of these vehicles require more of a driver than he may initially assume as evidenced by the number of injuries and deaths that have occurred. How can the number of deaths be reduced and the severity of injuries be lessened?

In vitro biomechanical studies were conducted on fresh human cadaveric thoracolumbar spines to establish the limits of tolerance, explain the mechanism of failure, and investigate the effects of improvement in strength and stability of the injured column using Harrington distraction rods, Luque rods and modified Weiss springs. Quasistatic axial tensile loading on ligaments, compressive loads on vertebra) bodies and intervertebral discs, and flexure and compression-flexion force vectors on ligamentous columns, intact torsos and injured spines were applied to delineate the biomechanical and functional patho-anatomic characteristics. Vertical drop tests were conducted with the Hybrid II manikin to predict the forces and accelerations on the vertebral column.

The continuing development of the F-15 has included improvements to its baseline Environment Control System (ECS), an open air cycle system built around a bootstrap air cycle machine. A simple air controller schedule change and the conversion to a High Pressure Water Separator (HPMS) ECS were steps in the evolution of the F-15 ECS which yielded gains in avionics cooling capacity of about 63%. Although there was no associated capacity increase, optimization of the cooling air distribution system was done to improve avionic reliability. Recent modifications of the F-15E aircraft to accommodate the Increased Performance Engines (IPE) have included ECS changes to maintain the capacity gains achieved previously. The higher bleed pressures and temperatures characteristic of the IPE have necessitated new pressure regulators, ducts, and heat exchangers. External scoops have been added to improve ram cooling airflow.

Serious injuries are caused to the chest and thoracic organs both in front and side automobile collisions, and statistical surveys indicate that overall chest injuries are the third most frequent after head and the lower limbs. For safer design of restraint systems and vehicle interiors experimental data has to be obtained to establish chest injury criteria. Unembalmed human cadavers were used to conduct nine frontal and fourteen lateral impacts including four with a simulated arm rest. All impacts used a six inch (15.2 cm) diameter impactor with impact velocities ranging from 12 mph (19.3 kph) to 20 mph (32.2 kph). Chest impacts were also conducted on rhesus monkeys and baboons to establish primate-human injury scaling criteria. Four human volunteers were used to obtain static load deflection curves in the lateral and frontal directions. The results of the above experiments and those conducted by other investigators are presented and analyzed.

All-Terrain Vehicles, usually called ATVs, are small motorized vehicles operating on three, four, or five low-pressure, high flotation tires that are “designed” for off-road use on a variety of terrains. As the use of these ATVs increased through the 1980's, the number of accidents resulting in serious injuries and deaths associated with A N use increased dramatically. The U.S. Consumer Product Safety Commission (CPSC) along with other surveys have estimated that one out of every 25 ATVs being used will be involved in an accident requiring professional medical attention. These problems led to the federal government working out an agreement with the major manufacturers of these vehicles. One aspect of the agreement was that there would be safety and stability standards that all ATVs would have to meet to be sold in this country.

The effect of frame flexibility on the stability of constant speed, straight line motions of a motorcycle is studied by reference to linearized differential equations governing the behavior of a system of five rigid bodies, two of which are connected to each other with a hinge, a spring, and a damper, and are intended to represent a flexible frame, while the rest represent the front fork and the wheels of the vehicle. Although the configuration of the system is characterized by seven generalized coordinates, it is shown that the stability information of interest can be deduced from four first-order differential equations.

Designing trucks for good ride characteristics is a challenge to the engineer, given the many design constraints imposed by requirements for transport productivity and efficiency. The objective of this lecture is to explain why trucks ride as they do, and the basic mechanisms involved. The response of primary interest is the vibration to which the driver is exposed in the cab. Whole-body vibration tolerance curves give an indication of how those vibrations are perceived at the seat; however, ride studies have shown that visual and hand/foot vibrations are also important to the perception of ride in trucks. The ride environment of the truck driver is the product of the applied excitation and the response properties of the truck. The major excitation sources are road roughness, the rotating tire/wheel assemblies, the driveline, and the engine.

The importance of fuel costs provide a strong incentive to operate the SST on existing jet fuels. Potential fuel system problems peculiar to the supersonic transport such as fuel boiling, spontaneous ignition, deposit formation, lubricity, and combustion characteristics are reviewed. The significance of these problems is established. Their severity depends on the particular environment provided by the designer. The difficulties of defining fuel properties to eliminate these problems are covered. The paper shows that major steps have been taken to operate the SST on current quality jet fuels but all necessary fuel quality control tests are not yet available.

To shape future mobility MAHLE has committed itself to foster wireless charging for electrical vehicles. The standardized wireless power transfer of 11 kW at a voltage level of 800 V significantly improves the end user experience for charging an electric vehicle without the need to handle a connector and cable anymore. Combined with automated parking and autonomous driving systems, the challenge to charge fleets without user interaction is solved. Wireless charging is based on inductive power transfer. In the ground assembly’s (GA) power transfer coil, a magnetic field is generated which induces a voltage in the vehicle assembly (VA) power transfer coil. To transfer the power from grid to battery with a high efficiency up to 92% the power transfer coils are compensated with resonant circuits. In this paper the Differential-Inductive-Positioning-System (DIPS) to align a vehicle on the GA for parking will be presented.

Forced inversion or eversion of the foot is considered a common mechanism of ankle injury in vehicle crashes. The objective of this study was to model empirically the injury tolerance of the human ankle/subtalar joint to dynamic inversion and eversion under three different loading conditions: neutral flexion with no axial preload, neutral flexion with 2 kN axial preload, and 30° of dorsiflexion with 2 kN axial preload. 44 tests were conducted on cadaveric lower limbs, with injury occurring in 30 specimens. Common injuries included malleolar fractures, osteochondral fractures of the talus, fractures of the lateral process of the talus, and collateral ligament tears, depending on the loading configuration. The time of injury was determined either by the peak ankle moment or by a sudden drop in ankle moment that was accompanied by a burst of acoustic emission. Characteristic moment-angle curves to injury were generated for each loading configuration.

Kia and Hyundai released publicly available tools in the spring of 2013 to read model year (MY) 2013 vehicle event data recorders (EDRs). By empirical testing, this study determined the tools also read data from some 2010-2012 models as EDRs were phased in by the manufacturer. Fifty-four (54) MY 2010-2012 airbag control module EDRs from the National Highway Traffic Safety Administration's (NHTSA) New Car Assessment Program (NCAP) crash tests were downloaded direct-to-module. The vehicles analyzed were exposed to frontal, side moving deformable barrier (MDB), and side pole tests. The EDR data was compared to the reference instrumentation for speed and Delta V data. Other data elements were also tabulated but are not evaluated for accuracy because they were not fully exercised during the crash tests, the reference instrumentation was not available, or they were outside the scope of this paper.

The accuracy of the Powertrain Control Module Event Data Recorder was tested during vehicle yaw and rotation on a flooded skid pad at the Michigan State Police training facility in Lansing, MI. The low friction of the skid pad allowed longer, slower rotations that allowed more detailed study of the behavior. The vehicle was deliberately put into rotation and allowed to rotate to rest under three different conditions: heavy throttle applied initially, heavy braking applied and held, and light to no throttle applied. Six runs were made under each condition. Data was collected from the PCM EDR and compared to a VBOX III (with IMU) 100 Hz differential GPS speed and yaw rate measurement system from which slip angle could be calculated. Graphs of PCM speed/brake/accel pedal data versus time showing VBOX speed and the cosine of the slip angle (where 1 = moving straight ahead and 0 = moving sideways) are presented.

It has been observed that locked-wheel skidding friction values are essentially vehicle- and tire-independent. It has been tacitly assumed by most crash reconstructionists that any ABS-equipped vehicle would also decelerate at nearly the same rate as any other ABS-equipped vehicle. This paper will review literature with relevant straight-line test results on paved roadways and gravel, and present additional results from recent tests generated with four modern vehicles built by three manufacturers. Results from the recent testing showed that locked-wheel skidding values on a concrete roadway were similar for all four vehicles, but the ABS-improvement on the same roadway varied. On gravel, ABS was always less effective than locked-wheel skidding. ABS and locked-wheel results on gravel had less car-to-car variation than tests conducted on concrete.

Mechanical shock tests for lithium metal and lithium-ion batteries often require that each cell or battery pack be subjected to multiple shocks in the positive and negative directions, of three mutually perpendicular orientations. This paper focuses on the no-disassembly requirement of those testing conditions and on the CAE methodology specifically developed to perform this assessment. Ford Motor Company developed a CAE analysis method to simulate this type of test and assess the possibility of cell dislodging. This CAE method helps identify and diagnose potential failure modes, thus guiding the Design Team in developing a strategy to meet the required performance under shock test loads. The final CAE-driven design focuses on the structural requirement and optimization, and leads to cost savings without compromising cell or pack mechanical performance.