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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.

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.

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..

The world is currently facing environmental issues such as global warming, air pollution, and high energy demand. To mitigate these challenges, the electrification of vehicles is essential as it is effective for efficient fuel utilization and promotion of alternative fuels. The optimal approach for electrification varies across different markets, depending on local energy conditions and current circumstances. Consequently, Toyota has taken the initiative to offer a comprehensive lineup of battery electric vehicles (BEV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and fuel cell electric vehicles (FCEV), aiming to provide sustainable solutions tailored to the unique situations and needs of each region. As part of this effort, Toyota has developed the 5th generation of hybrid electric vehicles. This paper describes the electric motor used in the new Toyota Camry which achieves high torque, high power, low losses, and compact design.

Stochastic Preignition (SPI) is an abnormal combustion phenomenon for internal combustion engines (ICE), which has been a significant impact to automotive companies developing high efficiency, turbocharged, direct fuel injection, spark ignited engines. It is becoming clearer what fuel properties are related to the cause of SPI, whether directly with fuel preparation in the cylinder, or mechanisms related to the deposit build-up which contributes to initial and follow-on SPI events. The purpose of this paper is to provide a summary of global market gasoline fuel properties with special attention given to properties and specific compounds from the fuel and fuel additives that can contribute to SPI and the deposit build-up in engines. Based on a review of the global fuel quality, it appears that the fuel quality has not caught up to meet the technology requirements for fuel economy from modern technology engines.

About 200,000 miles (~8 times around the earth) comprise the National Highway System, which carries most of the highway freight and traffic in the U.S. The core of the nation’s highway system is the 48,254 miles of Interstate Highways, which comprise just over 1 percent of highway mileage but carry over 25% of all highway traffic. Americans traveled a total of 5.3 trillion miles by all transportation modes in 2016, an average of 16,400 miles per person. About 80 percent was by automobile, truck, or motorcycle. Due to a high contribution to mobility and energy consumption, freeways and highway have been attracting researchers to move more vehicles faster and in energy-efficient manner. The research interest in motorways and highways has been driven by their significant impact on transportation efficiency and energy consumption, as they facilitate the movement of vehicles at higher speeds while optimizing energy usage.

With the increasing regulatory stringency on emission reduction and efficiency improvement, the automotive industry has experienced a significant shift in the hardware platform. Among technology candidates, hybrid technology is still considered one of the most viable approaches to meet the regulation requirement (both emission and efficiency) at an affordable cost to both the customer and the manufacturer. New engine operating characteristics are expected in hybrid applications which would potentially result in different performance requirements for the engine oil. Therefore, it is crucial to understand those characteristics of a hybrid powertrain, from which the insights of fluid requirements can be derived. A hybrid vehicle test study was conducted to evaluate the engine operation of different kinds of hybrid platforms. The hybrid operation has been well characterized by thoroughly analyzing parameters on each engine.

The paramount importance of titanium alloy in implant materials stems from its exceptional qualities, yet the optimization of bone integration and mitigation of wear and corrosion necessitate advanced technologies. Consequently, there has been a surge in research efforts focusing on surface modification of biomaterials to meet these challenges. This project is dedicated to enhancing the surface of titanium alloys by employing shot peening and powder coatings of titanium oxide and zinc oxide. Comparative analyses were meticulously conducted on the mechanical and wear properties of both treated and untreated specimens, ensuring uniformity in pressure, distance, and time parameters across all experiments. The outcomes underscore the efficacy of both methods in modifying the surface of the titanium alloy, leading to substantial alterations in surface properties.

INVOLUTE SPLINES enjoy three major advantages over their straight-sided counterparts: 1. New design concepts have given a more rational approach to clearances and errors. 2. Manufacturing is cheaper and more accurate. 3. Gaging is simpler. Thus, the involute spline standard of SAE and ASA continue to take precedence over the older straight-sided standards.

Testing of ducted fuel injection (DFI) in a single-cylinder engine with production-like hardware previously showed that adding a duct structure increased soot emissions at the full load, rated speed operating point [1]. The authors hypothesized that the DFI flame, which travels faster than a conventional diesel combustion (CDC) flame, and has a shorter distance to travel, was being re-entrained into the on-going fuel injection around the lift-off length (LOL), thus reducing air entrainment into the on-going injection. The engine operating condition and the engine combustion chamber geometry were duplicated in a constant pressure vessel. The experimental setup used a 3D piston section combined with a glass fire deck allowing for a comparison between a CDC flame and a DFI flame via high-speed imaging. CH* imaging of the 3D piston profile view clearly confirmed the re-entrainment hypothesis presented in the previous engine work.

This document presents a study on the design and simulation of a high-lift airfoil intended for usage in multielement setups such as the wings present on open-wheel race cars. With the advancement of open-wheel race car aerodynamics, the design of existing high-lift airfoils has been altered to create a more useful and practical general profile. Adjoint optimization tools in CFD (ANSYS Fluent) were employed to increase the airfoil’s performance beyond existing high-lift profiles (Selig S1223). Improvements of up to 20% with a CL of 2.4 were recorded. To further evaluate performance, the airfoil was made the basis of a full three-dimensional aerodynamics package design for an open-wheel Formula Student car. CFD simulations were carried out on the same and revealed performance characteristics of the airfoil in a more practical application. These CFD simulations were calibrated with experimental values from coast-down testing data with an accuracy of 8%.

A pedestrian involved traffic collision is generally less fully understood than the “typical” car-to-car broadside intersection collision. For this reason, the analysis of the pedestrian involved collision is, in many respects, more complicated and demanding. This paper addresses the typical sequence of events in a pedestrian involved collision and the movement of the vehicle and pedestrian body from pre-impact through the collision to their final points of rest. Methods for the analysis of the pedestrian involved collision, including a review of several different techniques for calculating vehicle impact velocity are also presented. A comparison of crash test data to different forms of analysis is provided as a frame of reference for the reader in evaluating these methods.