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Controller area network (CAN), FlexRay and local interconnect network (LIN) digital protocols are commonly used for communication in modern vehicles. A modern vehicle contains up to 70 electronic control units. This paper is a literature review of these protocols. We have also implemented LIN protocol. The communication cycle, process, message structure, and hardware elements are discussed for all three protocols. Performance is measured in terms of reliability and latency. In addition, a comparison between the CAN, FlexRay and LIN protocols is made. Experimental results indicate that CAN protocol has advantages when it comes to real-time priority-based communication. However, if all the events have equal priority, then FlexRay works well. The LIN protocol is budget friendly and has lowest cost in all 3 protocols but at the same time it is unreliable.

Connectivity has become an essential need for daily device users. With the car projected to be the “ultimate mobile device”, connectivity modules will eventually be mainstream in every car. Network providers are expanding their infrastructure and technology to accommodate the connected cars. Besides making voice and emergency calls the connected car will be sharing data with telematics service providers, back end systems and other vehicles. This trend will increase vehicle modules, complexity, entry points and vulnerabilities. This paper will present the current connected car architectures. The paper will present current architectural issues of the connected car and its vulnerabilities. The paper will present a new proposed architecture for the future connected car that enhances efficiency and security.

Cameras and image processing hardware are rapidly evolving technologies, which enable real-time applications for passenger cars, ground robots, and aerial vehicles. Visual odometry (VO) algorithms estimate vehicle position and orientation changes from the moving camera images. For ground vehicles, such as cars, indoor robots, and planetary rovers, VO can augment movement estimation from rotary wheel encoders. Feature-based VO relies on detecting feature points, such as corners or edges, in image frames as the vehicle moves. These points are tracked over frames and, as a group, estimate motion. Not all detected points are tracked since not all are found in the next frame. Even tracked features may not be correct since a feature point may map to an incorrect nearby feature point. This can depend on the driving scenario, which can include driving at high speed or in the rain or snow.

Global surrogate modeling aims to build surrogate model with high accuracy in the whole design domain. A major challenge to achieve this objective is how to reduce the number of function evaluations to the original computer simulation model. To date, the most widely used approach for global surrogate modeling is the adaptive surrogate modeling method. It starts with an initial surrogate model, which is then refined adaptively using the mean square error (MSE) or maximizing the minimum distance criteria. It is observed that current methods may not be able to effectively construct a global surrogate model when the underlying black box function is highly nonlinear in only certain regions. A new surrogate modeling method which can allocate more training points in regions with high nonlinearity is needed to overcome this challenge. This article proposes an efficient global surrogate modeling method based on a multi-layer sampling scheme.

Recently developed gasoline engines utilize more aggressive EGR rate to meet the emissions and fuel economy regulations. The EGR temperature is often estimated by the ECU and its accuracy affects the estimations of EGR flow rate and intake air flow rate and temperature. Therefore, the accuracy of EGR temperature estimation becomes more important than ever for precise EGR rate control. Typical lookup map based EGR cooler model without the sensitivity to the coolant flow rate is acceptable and widely used if the heat capacity of the coolant side is high enough. However, the coolant flow rate under real vehicle driving conditions often visit low-speed high-load part of the engine map where the lookup map based model suffers from the accuracy issues. This paper presents an investigation of the accuracy of the lookup map based model under different heat capacity conditions. In this study, a simple EGR cooler model based on effectiveness-NTU method was also developed.

With increasingly stringent emissions regulations and concurrent requirements for enhanced engine thermal efficiency, a comprehensive characterization of the automotive gasoline fuel spray has become essential. The acquisition of accurate and repeatable spray data is even more critical when a combustion strategy such as gasoline direct injection is to be utilized. Without industry-wide standardization of testing procedures, large variablilities have been experienced in attempts to verify the claimed spray performance values for the Sauter mean diameter, Dv90, tip penetration and cone angle of many types of fuel sprays. A new SAE Recommended Practice document, J2715, has been developed by the SAE Gasoline Fuel Injection Standards Committee (GFISC) and is now available for the measurement and characterization of the fuel sprays from both gasoline direct injection and port fuel injection injectors.

This paper presents an assessment of competing algorithms for normalizing volume levels between tracks and/or sources in an automotive infotainment system. Portable media players such as smartphones and iPod® devices are extremely popular for listening to music collections or streaming content from the Internet. The lack of normalization is a source of dissatisfaction if the user experiences significant changes in audio level between tracks. Several commercially available algorithms exist to solve this problem. This research includes a double-blind listening test comparing an audio sample processed with the different leveling algorithms to an unprocessed reference. The listener preference rating is recorded and results indicate which algorithm is preferred.

In automotive infotainment systems, multiple types of digital audio signals are usually present. Some come from internal sources, such as a CD or USB stick, and some come from external sources, such as an internet stream or digital radio. These sources usually have different sample-rates, and may also be different from one or more system sample-rates. Managing and transporting these signals throughout the system over different sample-rate domains require detailed upfront architecture analysis and correct system design to ensure signal quality is maintained to the desired level. Incorrect design can add significant user-perceivable noise and distortion. This paper examines the key analysis factors, the effects of poor design and the approaches for achieving robust signal handling and ensuring desired signal quality.

Accurate evaluation of vehicles' transient total power requirement helps achieving further improvements in vehicle fuel efficiency. When operated, the air-conditioning (A/C) system is the largest auxiliary load on a vehicle, therefore accurate evaluation of the load it places on the vehicle's engine and/or energy storage system is especially important. Vehicle simulation models, such as "Autonomie," have been used by OEMs to evaluate vehicles' energy performance. However, the load from the A/C system on the engine or on the energy storage system has not always been modeled in sufficient detail. A transient A/C simulation tool incorporated into vehicle simulation models would also provide a tool for developing more efficient A/C systems through a thorough consideration of the transient A/C system performance. The dynamic system simulation software MATLAB/Simulink® is frequently used by vehicle controls engineers to develop new and more efficient vehicle energy system controls.

The need for entertainment is a constant desire since human beans started to use vehicles for short and long distance travel. The radio, a home entertainment revolution, was the first one to be incorporated. The information and entertainment that initially brought the radio to the vehicles also started a major change on the interior and electrical systems. This revolution will require changes in vehicle design to accommodate the new concepts and features.

In this paper is a description of a simple virtual reality (VR) - controlled atmosphere brazing (CAB) furnace created using the virtual reality technology based on the physics of a simple thermal model. Within this VR-CAB furnace, engineers ‘walk’ through the furnace, and ‘observe’ the heating process inside the furnace. This VR-CAB furnace provides the framework which will ultimately allow engineers to control and improve the heat exchange processes in a realistically simulated environment, and study the effects of various process parameters that control product yield.

This paper describes a heat transfer model currently being developed for a next generation controlled atmosphere brazing furnace for production of automotive aluminum heat exchangers. This furnace will be numerically controlled to improve product yield. Part of the control loop decision will be based on predicted heat exchanger temperatures for set operating conditions. The numerical program is a transient heat transfer model simulating the radiant heat transfer between the furnace and the heat exchanger and the conduction heat transfer within the heat exchanger. The program solves the three-dimensional conduction equation for a solid using an implicit finite difference method. The boundary conditions to the solid is the radiant heat exchange. The program determines the radiant heat exchange based on the assumption of gray diffuse surfaces.

Successful simultaneous engineering requires a team with a high degree of engineering skill and experience, knowledge of the latest materials, processes, and methodologies; and it also requires finely honed people skills. Designing the workplace for people (DFP) can facilitate collaboration, increase quality and other significant metrics, and lead to an enhanced product greatly appreciated by the customer. Design for People applies the principles of performance technology to select and retain outstanding engineers, systematically train and educate for future competency needs, and reward and motivate through traditional and non-traditional approaches. Examples of best practice enable other organizations to apply the concepts of DFP.

Postal delivery vehicles provide an excellent opportunity for using electric propulsion, since the number of miles driven daily on the delivery route is established and consistent. The vehicles also return nightly to a central depot so charging infrastructure is not an issue as long as the vehicles have sufficient charge to complete the routes. The United States Postal Service has evaluated electric vehicles for postal carrier route vehicles several times. The latest trial concluded in 2001. During the test of electric postal carrier route vehicles, the range was usually adequate for the delivery route; however there were a few instances of vehicles having to be retrieved because they had exhausted their batteries. This paper describes a series hybrid electric vehicle that addresses range issues with an on-board internal combustion engine powered generator to extend vehicle range.

In this paper, an analytical procedure for prediction of shell radiated noise of air induction systems (AIS) due to engine acoustic excitation, without a prototype and physical measurement, is presented. A set of modeling and simulation techniques are introduced to address the challenges to the analytical radiated noise prediction of AIS products. A filter seal model is developed to simulate the unique nonlinear stiffness and damping properties of air cleaner boxes. A finite element model (FEM) of the AIS assembly is established by incorporating the AIS structure, the proposed filter seal model and its acoustic cavity model. The coupled acoustic-structural FEM of the AIS assembly is then employed to compute the velocity frequency response of the AIS structure with respect to the air-borne acoustic excitations.

Touch screens provide substantial benefits as a control and display system but still have some disadvantages. The availability of haptic (tactile) technology allows touch screens to function similarly to traditional mechanical controls. Two studies were undertaken to investigate the addition of haptic feedback as well as auditory feedback on user perceptions of the touch screen experience. The first study was conducted in a desktop setting and the second study was conducted with the touch screen integrated in a vehicle. In both studies, participants assessed four different types of feedback conditions: visual feedback only (V), auditory and visual feedback (AV), haptic and visual feedback (HV), and auditory, haptic, and visual feedback combined (AHV). The results of these studies support the claim that individuals strongly prefer touch screen implementations that incorporate haptic elements and also provide insights on regional differences in their perception.

First LED headlamps will be released into the market in 2007. Special permissions allow this introduction although the official regulation is still under discussion in ECE. The LED technology for front lighting has entered into a new phase from theoretical, prototype status to real and practical applications. Additionally in Europe the legislation, which is under preparation, defines LED modules with one or more LED chips in a row which should be replaceable. With this boundary conditions headlamp suppliers needs to balance between an attractive and innovative styling, demanded by car manufacturers and the light performance to gurantee good visibility at night. The paper describes the methods how to design an LED headlamp with high efficiency by keeping in mind the parameters: packaging, weight, styling and light perfromance. Results with specific design proposals are shown.

A conceptual study of a control strategy that improves vehicle handling during cornering maneuvers while improving vehicle roll stability is presented. From the vehicle rollover propensity estimated by vehicle states, the proposed control strategy generates different actuation forces between the front and the rear suspensions to meet its handling and roll stability objectives. Simulation results for different vehicle maneuvers show that the proposed algorithm can effectively balance between enhanced handling and rollover stability.

Light Emitting Diodes (LEDs) are fast becoming the preferred light sources for automotive lighting applications. They emit light at cone angles equal (hemispherical) or less (conical) than 2Π radians. One way for efficiently collecting and collimating light from LED light sources is to use Near Field Lenses (NFLs). NFLs are collimators using refraction and total internal reflection (TIR) to efficiently collect and direct light. They tend to have thick sections and therefore require challenging molding techniques, and they may have the LED source optically coupled directly into them. Beside these functional aspects, NFLs offer unique styling for different lighting functions such as those in rear combination lamps (RCLs), front turn signal lamps, daytime running lamps (DRLs) and headlamps.

Even though the use of LED's in automotive industry is continuously increasing, the test standards used for the thermal design of the lamps do not address the unique needs of LED based lamps. The challenge becomes more significant because LED's are semiconductor devices with lower maximum operating temperatures and photometric properties that depend on temperature. This paper presents sunload test results and lamp thermal data measured on vehicles undergoing simulated driving conditions in a lab environment. The data clearly indicates substantial differences in the measured data versus the test conditions to which the lamps are designed today. It is recommended to modify test standards that the lamps must meet to more closely emulate the field conditions.