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Electro-Mechanical Brake (EMB) is the brake system that is actuated by electrical energy and has a similar design with the Electric Parking Brake (EPB). It uses motor power and gears to provide the necessary torque and a screw & nut mechanism is used to convert the rotational movement into a translational one. The main difference of EMB compared with EPB is that the functional requirements of components are much higher to provide the necessary performance for service braking such as response time. Such highly responsive and independent brake actuators at each wheel lead to enhanced controllability which should result in not only better basic braking performance, but also improvements in various active braking functions such as integrated chassis control, driver assistance systems, or cooperative regenerative braking.

Electronic hydraulic control system adopted in the conventional vehicle continuously variable transmissions needs to consume energy incessantly for its oil pump driven by engine working continuously. As a result we can reduce the fuel consumption of the engine by removing the pump and replacing the control system with electro-mechanical one. The paper introduces two types of electro-mechanical controlled CVT (EM-CVT). One of them use gear train which is driven by a motor, and the other applies a planetary gear control device which uses spring to provide clamping force and electromagnetism clutches to control the planetary gears. The former is mainly applied to small torque CVT, for its clamping force brought from spring is limited. The latter can offer larger clamping force, and can be applied to prevalent CVT nowadays.

One of the key elements of response by many companies to the competitive environment is significant investments in new products. This increased competitive environment has been most influenced by international competition. Striving for “world class” products has to evolve if U.S. companies are to survive in the 1990s and beyond. While many large U.S. companies excel in basic research, with few exceptions they have had less than positive results in turning that advantage into a competitive edge as they introduce new products in the world marketplace. We cannot continue to believe that being first with a new technology is enough to enable us to thwart competition. Speed to market is extremely critical, as is the challenge of producing world class quality. Add to this the desire to recover our return on investment quickly.

This paper proposes an extension to curved surfaces of a design method of piezoelectric ice protection systems established for planar surfaces. The method is based on a finite element analysis which enables the fast computation of the resonant modes of interest to de-ice surfaces as leading edges. The performance of the modes of interest is assessed according to their deicing capacity estimated from the electro-mechanical coupling between the electric charge of the piezoelectric actuators and the strain energy in the structure. The method is illustrated on a NACA 0024 airfoil. Several experimental tests are conducted in an icing wind tunnel to verify the numerical predictions of the ice shedding and the operation of the system.

Hydraulic power requirements of military aircraft have increased significantly over the years. This has brought to the surface such issues as how best to manage the higher power requirements, which in many cases exist for only a small part of the duty cycle duration, and also how to minimize the system losses (heat rejection), which in turn can result in reduced cooling requirements. This paper summarizes some of the available data on the power requirements of military aircraft, discusses the inefficiencies of higher pressure systems being considered for high horsepower requirements, and describes the available approaches for better management of the high pressure/horsepower requirements, with respect to improving the operating efficiency of such systems.

The dual solenoid control valve was Initially designed as a low cost interface element between digital electronics and an automotive vacuum-spring motor such as the one found on Exhaust Gas Recirculation (EGR) valves. By using two coaxially located normally closed solenoids continuous air bleed is not required from the vacuum source. The direct acting solenoids have a large 0.5 SCFM flow capacity and a quick six millisecond opening and two millisecond closing time. The unit is well suited for pulse width modulation control. Ambient tests were conducted from -40°F to +250°F without any significant change in the performance characteristics of the unit. Possible applications for this electro-vacuum interface are in EGR valve control, Automatic Temperature Control (ATC), and as a remote throttle actuator on diesel engines.

This paper describes the design methodology and algorithm development towards the design of an automatic external gear-shifting and clutch-actuation system for a sequential gearbox with the aim of providing the drivers with easier and an efficient means of shifting gears. Automatically actuated manual transmission system bridges the gap between automatic and manual transmissions which provides the advantages of both type of transmissions. This would ideally leads to faster shifting time and provide significant benefits in the form of electronic-aids like launch control and traction control. Removal of mechanical clutching would reduce fatigue and lead to ergonomic benefit. Based on the benchmarking performed on an easily available ready-to-install aftermarket alternative, options will be considered for the actuating mechanism and the most feasible will be used to develop a shifting system.

With the increasing attention towards electric vehicles (EV), power electronics technology has become more prominent on vehicular systems. EV requires compact energy conversion and control technology to improve system efficiency and optimize the sizing of power components. Therefore, it is important to reduce thermal losses, while supplying an adequate amount of power to different EV devices. Silicon carbide (SiC)-based power semiconductors provide performance improvements such as lower power losses, higher junction temperature and higher switching frequency compared to the conventional silicon (Si)-based switching devices. High-frequency switching is preferred for power converters to minimize the necessity of passive filters; however, high-frequency switching causes additional thermal stress on semiconductor switches due to the increase in switching losses. The degradation of switching devices in power converters are primarily related to the junction temperature.

Lithium-ion (Li-ion) batteries are becoming widely used high-energy sources and a replacement of the Nickel Metal Hydride batteries in electric vehicles (EV), hybrid electric vehicles (HEV) and plug-in hybrid electric vehicles (PHEV). Because of their light weight and high energy density, Li-ion cells can significantly reduce the weight and volume of the battery packs for EVs, HEVs and PHEVs. Some materials in the Li-ion cells have low thermal stabilities and they may become thermally unstable when their working temperature becomes higher than the upper limit of allowed operating temperature range. Thus, the cell working temperature has a significant impact on the life of Li-ion batteries. A proper control of the cell working temperature is crucial to the safety of the battery system and improving the battery life. This paper outlines an approach for the thermal analysis of Li-ion battery cells and modules.

In the recent years, Hybrid and Electric Vehicles (EVs) have gained attention globally due to conventional non-renewable fuels becoming expensive and increasing pollution levels in the environment. Li-ion battery EV’s are most popular because of their better power density, spe. energy density and thermal stability. With the advent of battery EV’s, concerns regarding thermal safety of vehicle and its occupants has grown among the prospective customers. Temperature plays an important role in the performance of the Li-ion battery which includes cell capacity, charge output, vehicle range, mechanical life of the battery etc. For Li-ion cells, optimum operating range should be between 15-35 °C [1], and all cells must also be maintained within a ±5 °C variation band. Computational Fluid Dynamics (CFD) simulation can be used to get better insight of cell temperature inside battery. But CFD simulation process is complex, time consuming involving multi-physics and exhaustive computations.

A prototype fluidic fuel injection system for Spark-ignition(SI) engines has been established and tested. The fluidic injector unit combines a non-moving part wall reattachment type fluidic device powered by a solenoid pulser interface and an air-fuel mixing nozzle for good fuel atomization. It is demonstrated that the fluidic injector unit is capable of operating in a pulse modulated control mode and that the fluidic injector stage performs on-off switching in 1-1.5 msec.. The use of a fast response fluidic device coupled to a low power electric-fluidic interface potentially offers considerable cost and performance benefits for SI engine fuel injection systems.

The electromagnetic compatibility has been evaluated in vehicle components and systems, both individually and in the vehicle as a whole, already assembled with its numerous electrical and electronic equipment. The reason for this growing concern is the ever-increasing use of on-board electronics in cars. With the increasing speed of the processor in the modules and the demand for increasingly complex interfaces, it is necessary to develop more sophisticated control units, so the modules become ever more susceptible to electromagnetic fields. Therefore, the internal hardware of the control unit is designed to provide higher robustness of these components to comply in regards to EMC. The objective of this paper is to support the basic concepts that should be considered in building a printed circuit board (PCB) module for automotive application, and the correct component design distribution and ground strategy to avoid EMC issues.

The transportation industry, and in particular the automotive industry is undergoing the effects of two major events: in 2008 the soaring price of oil and in 2009 the global economic crisis. In addition to these events, new regulations are being signed into law in many countries around the world to reduce, or at least control, CO2 emissions. In parallel, to respond to these challenges, automotive manufacturers and suppliers are developing the internal combustion engine along 3 major trends: Downsizing with integration of turbocharger or supercharger Hybridization : from micro hybrid to full hybrid Low-cost engine for the just required performance These new powertrain systems call for a growing number of combustion modes and separate controls, dependent of the operating point, to satisfy all functional and legislative requirements. Likewise, they require new components which are more and more complex and controllable with greater accuracy.

A simple, battery-operated, long life, low maintenance, city transit electric bus has been developed with low pollution and low noise emission features. The Electrobus, built to accommodate 21-31 seated passengers, has been test driven in demonstration service more than 9000 miles in several large cities in the United States and Canada. Performance and power measurements have been taken from demonstrations at several typical urban center city bus service operations. From test results detailed in this paper, it is shown that the electric bus obtains 11.5 miles/gal of fuel compared to 3.5 and 6.0 miles/gal for equivalent sized gasoline and diesel engine buses in similar urban transit service.

Heart rate, blood pressure and e.c.g. tracings were investigated on 84 subjects (20 average drivers, 12 seniors, 32 test drivers and 20 women) driving their own cars over six different test routes (fast and slow town driving; fast and slow motorway driving; up- and down-hill driving). While blood pressure and e.c.g. tracings show no significant variations, heart rate increases from 71 ± 8 beats/min (at rest)to 90 ± 11 beats/min (max 145 beats/min) and shows irregular but continuous variations from ±8-10% to ±50% of the immediately preceding value within 6-8 to 30-50 seconds. The intervening nervous, humoral and metabolic factors (O2 consumption during driving) are also discussed.

Solid-state electrochemical cells can be used to sense and reduce NOx from combustion exhaust gases. In the reduction process the products are N2 and O2. For these cells to be effective in fuel-lean combustion exhaust, cathode materials with high selectivity for NO vs. O2 are necessary. Numerous materials were investigated for NO adsorption and reduction selectivity using temperature programmed desorption and reaction (TPD and TPR), respectively, and a summary of that investigation is given. Ceramic cells using these materials were fabricated and used to electrocatalytically reduce NO. An enhanced electrocatalytic three-way activity for NOx reduction was demonstrated that increases the window of operation into fuel-lean conditions. A process that combines selective absorption of NOx with three-way catalytic or electrocatalytic reduction to further increase the window of operation to higher oxygen concentrations was also demonstrated.

High energy and power density Lithium-ion batteries are used as energy storage devices for indispensable applications ranging from cell phones to hybrid electric vehicles, unmanned aerial vehicles and commercial passenger aircrafts. To monitor the health of the battery and its various performances, it is crucial to understand the electrochemical behavior of the battery. The Doyle-Fuller-Newman (DFN) model is a popular electro-chemistry-based model, which characterizes the solid and electrolyte diffusion dynamics in the battery and predicts current/voltage response. However, the DFN model requires many parameters that need to be estimated to obtain an accurate battery model. In this article, an electro-chemistry based cell model is developed using GT-AutoLion to simulate and validate the performance for two different commercially available Lithium Iron Phosphate (LiFePO4) and Nickel Cobalt Aluminum (NCA) cells.

Electrochemical amperometric sensors are widely used in environmental monitoring and in biomedical applications. These sensors have selectivity, fast response time, are small in size, use very low power, are easy to use and are potentially low cost. However, the conventional aqueous electrolyte based amperometric sensors have many drawbacks: they have limited operating life because of the high vapor pressure of aqueous based electrolytes, have poor baseline stability due to the build up of reaction products, and are expensive. To overcome these limitations, Honeywell has developed a new class of electrochemical gas and vapor sensors based on nonaqueous electrolytes. These sensors have a wide operating voltage, a wide operating temperature and have the potential for a long operating life. These sensors also have multigas sensing capability.

Major original equipment manufacturers (OEMs) have already marketed electric vehicles in large scale but apart from business strategies and policies, the real engineering problems must be addressed. Lithium-ion batteries are a promising technology for energy storage; however, their low energy density and complex electro-chemical nature, compared to fossil fuels, presents additional challenges. Their complex nature and strong temperature dependence during operation must be studied with additional accuracy, capable to predict their behavior. In this research, a pseudo two dimensional (P2D) electro-chemical model, for a recent high capacity NMC pouch cell for automotive applications is developed. The electrochemical model with its temperature dependent parameters is validated at high, low, and reference temperature within 10°C to 50°C temperature range. For each temperature various discharge C-rates to accurately replicate the battery cell operational conditions.

The aim of the present paper was to discuss, on the basis of electrochemical results and microscope observations, the representativeness of the Nissan OY water test (acidic solution containing chloride) used to evaluate the internal corrosion resistance of heat exchangers from the cooling loop. The corrosion behavior of brazed aluminum alloys (AA4343/AA3003*/ AA4343) was investigated in neutral and acidic solutions with and without chloride by electrochemical measurements. For the three layers present in the brazed material, i.e. the residual cladding, the band of dense precipitates (BDP) and the core material unspoiled by silicon diffusion, the polarization curves were obtained in the different media. It was observed that the core material presented good corrosion resistance in neutral solutions.