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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.

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.

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.

Recent advances in the state of the art of space-borne data processors and signal processors have occurred that present some unprecedented constraints relating to their power needs. Such processors include the class of multiprocessors providing computational capabilities in the billions of floating point operations per second. Processors of this type tend to require use of modern radiation tolerant or radiation hardened integrated circuits requiring very low voltage power supplies that place considerable challenge on power distribution and conversion within those processing payloads. The primary challenges are efficient conversion of power from the spacecraft power bus to these low voltages and distribution of the very high accompanying currents within the payload while maintaining proper voltage regulation (typically +/− 5%). Some integrated circuits require 10 Amps or more at 1Volt, as an example [3], [6].

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.

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.

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.

This paper describes a front road wheel steer-by-wire system with two actuator motors on the rack and pinion assembly to move the road wheels. Dual actuators are used to provide actuator redundancy and to enhance the fault tolerance capability. When one actuator faults or fails, the other actuator is designed to work independently and maintain full system performance. The paper emphasizes control method to implement the motion control for the front road wheel steer-by-wire system with two actuators on the common load. The proposed dual servo synchronization motion control implements the angle tracking for the road wheel reference input by controlling two actuators synchronously and cooperatively. It includes two servo feedback control loops to track the common reference input. The angular position error between two feedback loops is compensated using a synchronized compensator.

During last 10-15 years we could have seen quite big changes in automotive lighting. The most important changes are: a) plastic materials mostly removed metal and glass material from lighting products raised heat issue of plastics materials b) escalation of competition between lighting suppliers (globalization, merging, …) decrease of time and cost for development of the new product as much as possible

Electro-pneumatic valve actuators are used to eliminate the cam shaft of a traditional internal combustion engine. They are used to control the opening timing, duration, and lift of both intake and exhaust valves. A physics based nonlinear mathematical model called the level one model was built using Newton's law, mass conservation and thermodynamic principles. A control oriented model, the level two model, was created by partially linearizing the level one model for model reference parameter identification. This model reduces computational throughput and enables real-time implementation. A model reference adaptive control system was used to identify the nonlinear parameters that were needed for generating a feedforward control signal. The closed-loop valve lift tracking, valve opening and closing timing control strategies were proposed.

The traditional method of engine knock detection is to compare the knock intensity with a predetermined threshold. The calibration of this threshold is complex and difficult. A statistical knock detection method is proposed in this paper to reduce the effort of calibration. This method dynamically calculates the knock threshold to determine the knock event. Theoretically, this method will not only adapt to different fuels but also cope with engine aging and engine-to-engine variation without re-calibration. This method is demonstrated by modeling and evaluation using real-time engine dynamometer test data.

A practical and low cost Blind Spot Monitoring system is proposed. By using a single camera, the range and azimuth position of a vehicle in a blind spot are measured. The algorithm is based on the proposed RWA (Range Window Algorithm). The camera is installed on the door mirror and monitoring the side and rear of the host vehicle. The algorithm processes the image and identifies range and azimuth angle of the vehicle in the adjacent lane. This algorithm is applied to real situations. The 388 images including several kinds of vehicles are analyzed. The detection rate is 86% and the range accuracy is 1.6[m]. The maximum detection range is about 30[m].

As global automobile manufacturers prepare for the phase-out of R134a in Europe, they must address the issue of using the new refrigerant for European sales only or launching the product worldwide. Several factors play into this decision, including cost, service, risk, customer satisfaction, capacity, efficiency, etc. This research effort addresses the minimal vehicle-level hardware differences necessary to provide a European solution of R1234yf while continuing to install R134a into vehicles for the rest of the world. It is anticipated that the same compressor, lubricant and condenser; most fluid transport lines; and in most cases the evaporator can be common between the two systems.

This paper focuses on the numerical investigation of the mixing and combustion of ethanol and gasoline in a single-cylinder 3-valve direct-injection spark-ignition engine. The numerical simulations are conducted with the KIVA code with global reaction models. However, an ignition delay model mitigates some of the deficiencies of the global one-step reaction model and is implemented via a two-dimensional look-up table, which was created using available detailed kinetics models. Simulations demonstrate the problems faced by ethanol operated engines and indicate that some of the strategies used for emission control and downsizing of gasoline engines can be employed for enhancing the combustion efficiency of ethanol operated engines.

This paper gives an overview of a scalable engine management system architecture for motorcycle and other small engine based vehicle applications. The system can accommodate any engine sizes and up to four cylinders. The architecture incorporates advanced functionalities such as oxygen sensing, closed loop fueling, wall-wetting compensation, purge control, start & idle control and deceleration fuel cut-off. Additionally, a number of vehicle-related controls are integrated in the system. Diagnostic and safety related features have also been incorporated with limp-home capability. The software architecture is compatible with different hardware solutions. The system has been implemented in several OEM vehicles around the globe and meets EURO-3 emission requirements.