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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.

An attempt is made to describe the stability of vehicles on very rough terrain that may have large slopes. The basic premise of the paper is that the theory of ship stability is more applicable to problems of this kind than the traditional on-read vehicle stability theories. The linear theory is discussed as is driving on a rough slope, pitching, vertical oscillations and large angles. The methods of catastrophe theory as presented originally by Zeeman are used in an attempt to explain the behavior of the off-road vehicles.

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.

Since the early 1990’s, commercial vehicles have suffered from repeated vulnerability exploitations that resulted in a need for improved automotive cybersecurity. This paper outlines the strategies and challenges of implementing an automotive Zero Trust Architecture (ZTA) to secure intra-vehicle networks. Zero Trust (ZT) originated as an Information Technology (IT) principle of “never trust, always verify”; it is the concept that a network must never assume assets can be trusted regardless of their ownership or network location. This research focused on drastically improving security of the cyber-physical vehicle network, with minimal performance impact measured as timing, bandwidth, and processing power. The automotive ZTA was tested using a software-in-the-loop vehicle simulation paired with resource constrained hardware that closely emulated a production vehicle network.

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.

Aerospace Recommended Practice (ARP) 4754 Revision A (ARP4754A), “Guidelines for Development of Civil Aircraft and Systems,” [1] is recognized through Advisory Circular (AC) 20-174 (AC 20-174) [2] as a way (but not the only way) to provide development assurance for aircraft and systems to minimize the possibility of development errors. ARP4754A and its companion, Aerospace Information Report (AIR) 6110, “Contiguous Aircraft/System Development Process Example,” [3] primarily describe development processes for an all new, complex and highly integrated aircraft without strong consideration for reused systems or simple systems. While ARP4754A section 5 mentions reuse, similarity, and complexity, and section 6 is intended to cover modification programs, the descriptions in these sections can be unclear and inconsistent. The majority of aircraft projects are not completely new Products nor are they entirely comprised of complex and highly integrated systems.

In recent years, the burgeoning applications of hydrogen fuel cells have ignited a growing trend in their integration within the transportation sector, with a particular focus on their potential use in multi-rotor drones. The heightened mass-based energy density of fuel cells positions them as promising alternatives to current lithium battery-powered drones, especially as the demand for extended flight durations increases. This article undertakes a comprehensive exploration, comparing the performance of lithium batteries against air-cooled fuel cells, specifically within the context of multi-rotor drones with a 3.5kW power requirement. The study reveals that, for the specified power demand, air-cooled fuel cells outperform lithium batteries, establishing them as a more efficient solution.

Mechanical drawing plays an important role in managing, designing and implementing engineering projects, especially in the field of the automotive industry. The need for accuracy in element design and manufacturing is greater now than ever before in engineering industries. In order to increase accuracy, the part design and function must be clearly communicated between the design engineer and the manufacturing technicians, especially in automotive industry and feeder industries projects. Geometric Dimensions and Tolerances (GD&T) system of elements determines the quality, importance and price of the designed product. The standard used in the United States to define GD&T methodology is ASME Y14.5-2009 while the standard used in Europe is ISO 1101-2017. This article discussed the importance of using GD&T system including the types of geometrical features, limitations and accuracy, datum references frame and feature control frame to handle these symbols seamlessly.

This paper analyzes the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. Current control includes current vector control, MTPA control, flux weakening control, PI current control and SVPWM control. Motor mode includes initialization mode, normal mode, fault mode, active discharge mode, power off mode, battery heating mode and boost mode. The boost strategy of the hybrid system is based on boost mode management, boost target voltage determination and boost PI control. The specific content is as follows: Boost mode control. Boost mode includes initial mode, normal mode, off mode and fault mode. Boost target voltage is determined. Boost converter is controlled by variable voltage, which depends on the operation status of the motor and generator..