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Moto GP engines have since the year 2012 4 cylinders in V or inline layout for a total capacity of up to 1,000cc. With pneumatic valve spring but wet sump, and with the maximum bore limited to 81mm, the maximum speed these engines may have is about 18,000 rpm, with power outputs 250-260 HP. The paper presents the design of a 65 degree V4 Moto GP engine further optimizing the pneumatic poppet valve design, as well as a novel rotary valve design. The rotary valve permits up to extremely sharp opening or closing and very large gas exchange areas. The two engines are then modeled by using a 1D engine & gas dynamics simulation software package to assess the potentials of the solution. The improved design produces much larger power densities than the version of the engines with traditional poppet valves revving at higher speeds.

Statistical studies of collision and non-collision fires abound, founded upon information in publicly available collision and fire incident data bases. Recent efforts to improve the quality and reliability of the data within such databases have included the development of vehicle fire investigator training materials for motor vehicle crash investigators. These materials will be available to investigators both as a computer-based training system for remote learning and as a classroom seminar. When completed, the computer-based training course will be publicly available. The computer-based training course is based on published and unpublished research on vehicle fires, material properties and ignition characteristics. Topics include a discussion of combustible fluids and materials, ignition sources, burn patterns, arson, hybrid vehicles and vehicle design, as well as background information on fire science, automotive systems, and design and investigation standards.

This paper uses NASS/CDS 1997-2004 to determine the crash factors that are most frequently associated with rollover fires. Rollover fire cases were analyzed by the NASS variables including vehicle type, fire origin, number of quarter-turns, and final rest position. Results show that the engine compartment was the most frequent location for the fire origin. The fuel tank was second in this category. The rest position on the roof was most frequently associated with fires in rollovers. However, the fire rate was not strongly influenced by the final rest position. High severity rollovers that involve more than eight quarter-turns or end-over-end motion had fire rates much higher than the average. An examination of 24 cases with major fires in recent model year vehicles found that impacts prior to the rollover occurred in more than half of the cases. All of the cases with leakage from the fuel tank had impacts prior to the rollover.

This paper describes an investigation that seeks to understand how rollovers occur in real-world crashes, both by studying real world crashes and by analyzing vehicle handling tests to gain insights into potential mechanisms of pre-crash loss of control. In particular, this study focuses on one type of rollover, namely single-vehicle rollovers that follow a pattern of the vehicle first leaving the roadway and then returning to the roadway typically out-of-control. Aims of this study included the following: To describe the frequency and characteristics of single-vehicle rollovers involving an off-roadway excursion followed by a complete, if only temporary return to the roadway. To the extent possible, given available data, to assess the nature and consequences of driver inputs during the crash sequence. To define characteristics of crash scenarios which include a substantial proportion of this subset of single-vehicle rollovers.

The National Highway Traffic Safety Administration (NHTSA) conducted a total of 28 frontal crashes in the New Car Assessment Program (NCAP) involving the 10-year-old child Hybrid III dummy. The 10-year-old child dummy was in the rear seat. All types of vehicles (passenger cars, sport utility vehicles, vans and pick-up trucks) were tested to assess the effect of restraint systems such as booster and pretensioner on the rear seat occupant. In this study, the readings of the 10-year-old child dummy in rear-left and rear-right seat positions are examined. The authors apply a possible 5 star rating system, based on head and chest readings of the 10-year-old dummy. The paper also assesses the safety performance of rear seat occupants and the effect of the restraint systems on a child in the rear seat. This paper suggests that a star rating for rear seat occupants is independent of the present ratings for the driver and front adult passenger in NCAP.

In this paper, a high response, greater flow and higher pressure solenoid valve is developed. The valve's dynamic electromagnetic characteristics are analyzed by experiments. The fast response of the valve is obtained by material and structural modifications. The lifetime of solenoids may be extended. By analyzing and calculating with finite element method, the magnetic core's structural parameters and the magnetic coil parameters are optimized. The power control and drive method are discussed. The energy consumption is decreased. A method is provided for demagnetizing the magnetic core to release the valve core. So that the response time of solenoid are further shortened. The test results proved that the solenoid valve developed in this paper is of a maximum flow of about 35l/min, 100bar pressure dispersion and 0.89ms respond time. By using this valve, injection quality hopes to be improved and the exhaust emission hope to be decreased.

Of the injuries sustained by belted rear occupants in a frontal collision event in Japan, the neck and the head are the regions of the body most likely to be injured, while children and female occupants are accounting for the highest rate of injuries. For the purpose of reducing rear seat occupant injuries, the occurrence mechanism of neck and head injuries is clarified by sled tests with the current rear seat belt system. When a high load is applied to the occupant via the seat belt, the occupant experiences sudden deceleration of the chest, resulting in a great relative velocity difference between the head and the chest. This causes injury to the occupant's neck and head. To reduce occupant injuries, therefore, it is important to minimize the relative velocity difference by control of belt load.

The objective of this paper is twofold: 1 To generate awareness in the automotive industry of the United States Government (USG) Global Positioning System (GPS) Modernization programs in order to stimulate thought and innovation for future GPS automotive applications that enhance the safety, efficiency and pleasure of driving an automobile. 2 To solicit active participation by the automotive industry in helping to determine the GPS position, velocity and timing requirements for the next 30 years. There is a unique opportunity to influence the designs of the next generation of GPS, called GPS III, to meet the needs of the predominant GPS user, the civil GPS community. The automotive industry represents a significant part of the civil GPS community and it is very important that your future GPS requirements, as well as those of the driving public, are being met in GPS III.

The design of a race engine intake system involves many design considerations. Two very important areas of design are the intake manifold's volume and geometry. In considering these variables there are several different possible intake configurations. Such configurations will include single and dual plenum designs, as well as volume transitions. Dynamometer testing objectives will test different intake designs for the best overall engine power by comparing the areas under the engine power curve. Of the four intakes tested, the 2003 intake was found to make the best overall power.

Positional accuracy of GPS measurement has been based on simulation and actual measurement due to the difficulty of conducting 24-hour actual running tests. However, the conventional measurement is only based on brief evaluation; hence variability of positional accuracy which varies depending on measurement time and location had been an issue. Thus, it is significant to show the validity by the estimation of positional accuracy, and actual measurement using of lengthy simulation. In this study, actual measurement data in an urban area was obtained for long hours, and a simulation using 3D maps was implemented. A high precision positional measurement system was equipped on a vehicle in order to collect actual measurements and positional data at each measurement time. The data obtained by the measurement system was used as the reference coordinate for both the simulation and the actual measurements.

The GPS (Global Positioning System) is a navigational tool available to the public, comprising in part a network of satellites in orbit broadcasting signals to GPS receivers on earth. Due in large part to the very accurate clocks in the system, a GPS receiver that receives a number of these signals simultaneously can then establish its location on earth. Some GPS receiver models have the capability to record a history of the latitude and longitude co-ordinates at known times, and these may later be downloaded and viewed on a computer using applicable software. Effectively, this provides the equivalent of a bread crumb trail of the path taken by the receiver, although the frequency of the data points can vary substantially from one model to another, and it may not be adjustable by the user. By plotting the information on a map, the trail can be viewed and the position-time history of the vehicle may become evident.

The majority of a refuse truck collection cycle consists of frequent Stop and Go events while moving from one household to another. The nature of this driving mission creates the opportunity to reduce fuel consumption by capturing and re-using the kinetic energy normally wasted during braking. This paper includes the evaluation of the brake energy available for regeneration from the conventional drivetrain; the description of the impact of the vehicle variable mass and auxiliary loads; a model validation over a real-world duty cycle; and the potential for an increase in fuel efficiency through hybridization of the drivetrain. The Hydraulic Hybrid (HH) technology is selected since it has a large power density.

Photogrammetric techniques of analyzing vehicles and scenes for accident reconstruction are well documented and have appeared in various forms and levels of complexity over the years. Plane-to-plane rectification algorithms, frequently used for accident reconstruction, are subsets of a growing field of computer vision algorithms, which are rigorously developed in [1,2,3,4]. While these algorithms are well formulated, they are not well illustrated. It is often not clear how to leverage advancements in computer vision algorithms for the purposes of rectification photogrammetry in the context of accident reconstruction. Perhaps as expected, a second strategy exists in the literature, which describes the use, as opposed to the development, of commercial computer programs for rectification photogrammetry [5,6,7,8]. Commercial software applications provide a robust and wide array of photogrammetric analysis.

Improvement in fuel economy and reduction in emissions are the two major driving forces in the advancement of automotive engine technologies, fuel quality, lubricants, and aftertreatment devices. Engine design, operating conditions such as speed and load, and engine oil behavior have a significant influence on engine friction and then the vehicle fuel economy. There is no standard short duration engine test available to evaluate engine oil’s friction. This study developed a test protocol to discriminate friction reduction efficacy of engine oils/additives to support in the development of engine oils. The engine test facility was modified to conduct the motoring test over the speed range of 1000 - 4500 rpm and at 50 - 100 °C coolant and oil temperatures. Different viscosity grades and additive chemistry i.e. combination of friction modifiers & viscosity modifiers was evaluated over the motored torque test.

The electricity energy consumption for passenger cabin heating can drastically shorten the driving range for electric vehicles in cold climates. Mobile heat pump system is considered as an effective method to improve heating efficiency. This study investigates the system characteristics of mobile heat pump systems for electrical vehicle application. Based on KULI thermal management software, simulation models including HFC-R134a direct heat pump (DHP) and secondary loop heat pump (SLHP) were developed. The secondary loop employed in the SLHP includes a coolant pump, an indoor heater core and a plate heat exchanger, instead of an indoor condenser in the DHP. The use of a secondary loop has advantages to improve air outlet temperature uniformity. The simulation models were verified by measured data obtained from calorimeter experiments. By adopting simulation models, the effects of indoor and outdoor temperatures on system performance and cycle characteristics were discussed.

Over the past few years, China has made major legislative advancements on vehicle emissions, having set forth Stage 6 regulations for both LD and HD vehicles. To meet stricter standards, OEMs and associated suppliers of the exhaust aftertreatment value chain have gone through a period of unprecedented development. This paper selectively describes key challenges and highlights corresponding solutions of those development for both segments. In doing so, the authors wish to provide an overview of the catalyst systems used in upcoming China automobile market. A key challenge for LDG Stage 6 is the introduction of FWCTM (Four-Way Catalysts, aka cGPF - Coated Gasoline Particulate Filter). This paper discusses advantages and disadvantages of different system solutions. Experimental study showed oxygen and temperature are critical factors to achieve effective soot regeneration in a FWCTM.

Conventional cruise control systems in automotive applications are usually designed to maintain the constant speed of the vehicle based on the desired set-point. It has been shown that fuel economy while in cruise control can be improved using advanced control methods namely adopting the Model Predictive Control (MPC) technology utilizing the road grade preview information and allowance of the vehicle speed variation. This paper is focused on the extension of the Adaptive Nonlinear Model Predictive Controller (ANLMPC) reported earlier by application to the trailer tow use-case. As the connected trailer changes the aerodynamic drag and the overall vehicle mass, it may lead to the undesired downshifts for the conventional cruise controller introducing the fuel economy losses. In this work, the ANLMPC concept is extended to avoid downshifts by translating the downshift conditions to the constraints of the underlying optimization problem to be solved.

By 2030, about 95% of new vehicles sold globally will be connected, up from around 50% today. Around 45% of these vehicles will have intermediate and advanced connectivity features (source: McKinsey, 2021). Modernization, standardization, and automation are the key steps in the roadmap of data handling for connected vehicles. Vehicle software increasingly sits within a connected ecosystem of devices. Consumer expectations are shifting more towards digital compatibility, connectivity, and new functionalities offered in autonomous vehicles. Digitalization is turning the vehicles of the future into commodities that are as experimental as they are useful. Many OEMs are at the beginning of this transformation journey and have struggled on the software side of things. The entire automotive industry is putting its efforts into effectively monetizing the data captured during the development and management of autonomous vehicles.

Given that it improves engine efficiency and performance, the intake manifold is regarded as a critical component of the internal combustion engine (ICE). The right fuel-air mixture intake, which depends on the material geometry of the intake manifold, allows for the burning of the desired fuel-air combination. The current study concentrates on the geometric modelling, structural analysis, and modal analysis of the intake manifold. By using Finite Element Analysis (FEA) software, static structural linear analysis and heat analysis were conducted to evaluate the structural safety. Following investigation, modal analysis revealed a minimum deformation of 56.34 mm at a frequency of 977.45 Hz and a maximum deformation of 104.22 mm at a higher frequency of 2518.1 Hz. According to study, the intake manifold structure is more vibration-resistant than cast iron when compared to aluminum and other materials. Cast iron and aluminum were used as the material for the thermal analysis.

There is a demonstrated need for effective design verification testing to support certification strategies for nascent electric motors and electric propulsion systems. Design efforts pursue efficiency pushing electrified propulsion rotors to be lighter and incorporate greater power density; however, there is no clear path established for supporting structural integrity and durability test requirements as required by global certification agencies. Application of new materials, unique rotor design characteristics, and modified certification requirements drive unusual requirements for rotor modeling substantiated by component test data that addresses complex stress distribution characteristics. Our paper addresses testing electrified propulsion rotors using spin test protocols adapted to support integrity and durability test goals.