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Today's automotive and electronics technologies are evolving so rapidly that educators and industry are both challenged to re-educate the technological workforce in the new area before they are replaced with yet another generation. In early November 2009 Ford's Product Development senior management formally approved a proposal by the University of Detroit Mercy to transform 125 of Ford's “IC Engine Automotive Engineers” into “Advanced Electric Vehicle Automotive Engineers.” Two months later, the first course of the Advanced Electric Vehicle Program began in Dearborn. UDM's response to Ford's needs (and those of other OEM's and suppliers) was not only at the rate of “academic light speed,” but it involved direct collaboration of Ford's electric vehicle leaders and subject matter experts and the UDM AEV Program faculty.

Thermally sprayed engine bores require surface preparation prior to coating to ensure adequate adhesion. Mechanical roughening methods produce repeatable surfaces with high adhesion strength and are attractive for high volume production. The currently available mechanical roughening methods are finish boring based processes which require diameter-specific tooling and significant clearance at the bottom of the bore for tool overtravel and retraction. This paper describes a new mechanical roughening method based on circular interpolation. This method uses two tools: a peripheral milling tool, which cuts a series of concentric grooves in the bore wall through interpolation, and a second rotary tool which deforms the grooves to produce an undercut. This method produces equivalent or higher bond strength than current surface preparation methods, and does not require diameter-specific tooling or bottom clearance for tool retraction.

With the trending electrification of vehicle accessory drives brings new control concepts useful in many cases to optimize energy management within the powertrain system. Considering that direct engine drives do not have as much flexibility as independent electric drives, it is apparent that several advantages are to be expected from electric drives. New developed high efficient electric drives can be implemented when considering many vehicle sub-systems. Combinations of continuous varying and discrete flow control devices offer thermal management opportunities across several vehicle attributes including fuel economy, drivability, performance, and cabin comfort. Often new technologies are integrated with legacy systems to deliver maximum value. Leveraging both electrical and mechanical actuators in some cases presents control challenges in optimizing energy management while delivering robust system operation.

Selection of the DC-link capacitance value in an HEV/EV e-Drive power electronic system depends on numerous factors including required voltage/current ratings of the capacitor, power dissipation, thermal limitation, energy storage capacity and impact on system stability. A challenge arises from the capacitance value selection based on DC-link stability due to the influence of multiple hardware parameters, control parameters, operating conditions and cross-coupling effects among them. This paper discusses an impedance-based methodology to determine the minimum required DC-link capacitance value that can enable stable operation of the system in this multi-dimensional variable space. A broad landscape of the minimum capacitance values is also presented to provide insights on the sensitivity of system stability to operating conditions.

The hazard analysis for the Stop-Start control strategy of a Micro-Hybrid vehicle with manual gearbox is presented. The strategy allows for stops in gear and in neutral; this leads to specific hazards. Implications for the architecture of the electronic control unit, the software architecture, and the development process, especially software testing, are discussed.

The brake pedal is the brake system component that the driver fundamentally has contact and through its action wait the response of the whole system. Each OEM defines during vehicle conceptualization the behavior of brake pedal that characterizes the pedal feel that in general reflects not only the characteristic from that vehicle but also from the entire brand. Technically, the term known as Pedal Feel means the relation between the force applied on the pedal, the pedal travel and the deceleration achieved by the vehicle. Such relation curves are also analyzed in conjunction with objective analysis sheets where the vehicle brake behavior is analyzed in test track considering different deceleration conditions, force and pedal travel. On technical literature, it is possible to find some data and studies considering the hydraulic brakes behavior.

Deformation of the hub, rotor, and the wheel results in lateral run-out of the rotor. The effect of contact surface variations and bolt forces on the deformation is investigated. It is analytically shown that the run-out due to deformation is caused primarily due to the radial and circumferential moments generated in the hub and the rotor due to bolt tightening. Case studies illustrate the interaction between hub, rotor, and the wheel for various surface conditions. Design guidelines are provided to reduce rotor run-out.

Vehicle sensitivity to brake induced vehicle vibration has been one of the key factors impacting overall vehicle quality. This directly affects long term customer satisfaction. The objective of this investigation is to understand the sensitivities of a given suspension, and steering system with respect to brake induced vehicle vibration, and develop possible solutions to this problem. Design of experiment methods have been used for this chassis system sensitivity study. The advantage of applying the design of experiment methodology is that it facilitates an understanding of the interactions between the hardware components and the sensitivity of the system due to the component change. The results of this investigation have indicated that the friction of suspension joints may affect vehicle system response significantly.

High mileage NVH performance is one of the major concerns in vehicle design for long term customer satisfaction. Elastomeric bushings and brake rotors are key chassis components which tend to degrade as vehicle mileage accumulates with time. The degradation of these components normally causes the overall degradation of vehicle NVH performance. In the current paper two categories of problems are addressed respectively: road-induced vibration due to bushing degradation, and brake roughness due to rotor wear. A system integration approach is used to derive the design strategies that can potentially make the vehicle more robust in these two NVH attributes. The approach links together bushing degradation characteristics, brake rotor wear characteristics, the design of experiment (DOE) method, and CAE modeling in a systematic fashion. The concept and method are demonstrated using a production vehicle.

As part of determining the circumstances of a crash, sometimes components or component assemblies are evaluated to identify if they were damaged as a result of the crash or if they lost function prior to the crash. What role the loss of function may have contributed to the crash is useful in determining if they lost function prior to the crash. The causes and conditions for a brake rotor hub separation from the spindle of a vehicle with tapered roller bearing designs are analyzed through both component level testing and full vehicle testing. Laboratory tests were performed on component assemblies where loads were applied to the wheel assembly and the residual damage to the components was documented. In addition, full vehicle testing was conducted to evaluate the effects of a hub and rotor separation on vehicle control and to document evidence on the components. Real world case studies of hub and rotor separations are presented.

In-vehicle electronics are becoming more and more important; the functionalities are being distributed across several electronic control units (ECUs). These can be divided into body systems as well as new powertrain and chassis control systems. It is foreseen that the value of software per vehicle will increase for a normal vehicle. This situation creates the demand to perform a study to understand the trends and impacts of a massive electrification of the vehicle. This study and survey aims to identify the current status of the Vehicles E/E Architectures and the In-Vehicle Networks of Brazilian B entry vehicles. It is important to have in mind that Brazilian market represents about 70% of the total South America automotive industry. The study was divided into two parts: The first part approaches the topics above in generality. Goal was to identify the current electrical architecture elements affecting the B entry vehicles versus the main attributes for this kind of segment.

One-dimensional single-zone and two-zone analyses have been exercised to calculate the mass fraction burned in an engine operating on ethanol/gasoline-blended fuels using the cylinder pressure and volume data. The analyses include heat transfer and crevice volume effects on the calculated mass fraction burned. A comparison between the two methods is performed starting from the derivation of conservation of energy and the method to solve the mass fraction burned rates through the results including detailed explanation of the observed differences and trends. The apparent heat release method is used as a point of reference in the comparison process. Both models are solved using the LU matrix factorization and first-order Euler integration.

While SAE double inverted flares have been in use for decades, leaking joints continue to be a problem for OEMs in production settings consuming time and energy to detect and correct them before releasing vehicles from the assembly plant. It should be noted that this issue is limited to first-time vehicle assembly; once a flared brake tube joint is sealed at the assembly plant it remains sealed during normal customer usage. From their inception through the late 1980s most brake tubes have been 3/16″ nominal diameter. With the advent of higher flow requirements of Traction Control and Yaw/Stability control systems, larger tubes of 1/4″ and 5/16″ size have also been introduced. While it was known that the first-time sealing capability of the 3/16″ joint was not 100%, leakers were generally containable in the production environment and the joint was regarded as robust.

Compressibility is a common quality metric for friction materials. In addition, it is typically used as an engineering parameter for brake system design and performance. Compressibility (or elastic properties) of the friction material can effect brake roughness, pedal feel, and noise performance. A characterization technique is presented to determine the cyclic compressibility (over ± 1 kN) as a function of preload, temperature, frequency and time. The initial motivation was related to modeling of brake roughness, but applications to pedal feel and brake noise are also explored. For a given semi-metallic material, changing the temperature from 20 to 300°C or the preload from 8 to 4 kN both halve the cyclic compressibility. Less significantly, a change in frequency from 20 to 1 Hz reduces the cyclic compressibility by 10%. Differences between linings are also considered.

Since the technology applied to vehicles is constant increasing, new systems are being developed to improve performance, comfort and safety. The main way to improve safety is to keep the driver informed about unsafe traffic. In this paper we propose the development of an algorithm that works with an Antilock Brake System, in order to keep the driver informed about the distance between the vehicle equipped with this system and another one in front of it, by this way there is more time to make a safe breaking. The interaction between the driver and this method is given by a visual alert system.

Brake system development and testing is spread over vehicle manufacturers, system and component suppliers. Test equipment from different sources, even resulting from different technology generations, different data analysis and report tools - comprising different and sometimes undocumented algorithms - lead to a difficult exchange and analysis of test results and, at the same time, contributes to unwanted test variability. Other studies regarding the test variability brought up that only a unified and unambiguous data format will allow a meaningful and comparative evaluation of these data and only standardization will reveal the actual reasons of test variability. The text at hand illustrates that a substantial part of test variability is caused by a misinterpretation of data and/or by the application of different algorithms.

Noise source identification has been a subject well studied in the past few years. Automobile manufactures along with specialized supplies have been developed some methods in this matter. The importance of such subject is quite obvious, especially in the auto industry: identify potential problems and point out solutions for NVH. There are several methods of noise source identification widely used. Among them, one can mention "Hotspot Search," which consists of noise intensity measurement, mapping and ranking the relative contribution of each substructure of one body. Another method used, one can point out is the STSF (Spatial Transformation of Sound Fields). It consists of a measurement over a scan plane using a set of microphone array. In this way, a 2D sound field can be transformed in a 3D description and source direction can be identified.

Gliders can climb to substantial altitudes without employing any on-board energy resources but using proper piloting skills to utilize rising air currents called thermals. Recent experiments on small Unmanned Aerial Vehicles (UAVs) indicate a significant potential to increase both the flight velocity and the range of gliders by means of such maneuvers. In these experiments the velocity to approach a thermal has been recognized as a critical performance factor, and is chosen as the controlled variable. Accurate longitudinal controllers are required to track the optimal flight trajectories generated using path planning algorithms. These controllers are challenged by the presence of uncertain and time-varying aircraft dynamics, gust disturbances, and control actuator limitations.

From the brake system point of view the world can be split into comfort and performance markets. This market split evolved historically and reflects local legal requirements, driving style and the customer expectations. Noise, cold judder and brake dust play the dominant role in the perception of the customer on the comfort market. The performance markets call for high friction level and good fade performance. Currently these customer needs can only be satisfied by usage of different pad materials: NAO and Semi Met materials for comfort markets and generally Low Met materials for performance markets. Due to the differences mentioned above, additional brake system development and testing is done (different testing locations for the same brake attribute). Harmonizing testing, usage of the same test location and same test method could save not only the human resources but also decrease the number of prototypes used in the development phases.

Ford's H2RV is a Hydrogen engine propelled Hybrid Electric concept Vehicle that was unveiled and driven at Ford's Centennial Show in June 2003. This vehicle is an industry first by an OEM that demonstrates the concept and the marriage of a HEV powertrain with a supercharged Hydrogen ICE that propels the vehicle. Just as Model T was the car of the 20th century, Model U is the vehicle for the 21st century. The powertrain utilizes compressed gaseous hydrogen as fuel, a supercharged 2.3L internal combustion engine, a 25 kW traction motor drive, the electric converterless transmission, regenerative braking, an advanced lithium ion battery, electric power assist steering, electronic throttle and Vehicle System Controller (VSC). The vehicle could deliver a projected fuel economy of 45 mpg and near zero emissions without compromise to performance.