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Spot, or distributed, cooling and heating is an energy efficient way of delivering comfort to an occupant in the car. This paper describes an approach to distributed cooling in the vehicle. A two passenger CFD model of an SUV cabin was developed to obtain the solar and convective thermal loads on the vehicle, characterize the interior thermal environment and accurately evaluate the fluid-thermal environment around the occupants. The present paper focuses on the design and CFD analysis of the energy efficient HVAC system with spot cooling. The CFD model was validated with wind tunnel data for its overall accuracy. A baseline system with conventional HVAC air was first analyzed at mid and high ambient conditions. The airflow and cooling delivered to the driver and the passenger was calculated. Subsequently, spot cooling was analyzed in conjunction with a much lower conventional HVAC airflow.

Side impact accounts for a significant source of societal harm, injury and death. To address this issue, Europe and US have introduced legislation to be met for the new vehicle certification. In an effort to meet these regulations and the market demand for safety, Automotive manufacturers have significantly improved vehicle side structure integrity and introduced side impact airbags are for added protection. Today, passenger vans, light truck and sport-utility type vehicles are all popular consumer choices in the US. These vehicles differ significantly from passenger cars in many respects and as such need special design considerations for side airbags. Here, MADYMO-3D model of a generic passenger van / Sport-Utility type vehicle is created and correlated to FMVSS-214 side impact crash test. This model is used to evaluate both door and seat mounted side airbag designs in different orientations at standard test impact condition and at a higher speed.

One of the most evident trends in automotive sector is miniaturization. It is related to considerable benefits due to the potential of mass reduction, cost reduction and efficiency improvement. It involves many different automobile components and most of them are facing challenges to achieve the targets defined by car makers and final consumers. Specifically for wiring harness, it seems to be many manufacturing and process challenges to be surpassed in order to fully perceive the benefits expected with miniaturization, internally and externally. So this article aims to present an overview of literature as well as reporting of experts on this issue mentioning some of the challenges that global automotive wiring harness manufacturers are facing. Subjects as assembly automation, terminal connection and small gauge cables are discussed in the article and also a general overview of how those problems are being addressed in order to meet customer requirements.

Lithium-based battery technology offers performance advantages over traditional battery technologies at the cost of increased monitoring and controls overhead. Multiple-cell Lead-Acid battery packs can be equalized by a controlled overcharge, eliminating the need to periodically adjust individual cells to match the rest of the pack. Lithium-based based batteries cannot be equalized by an overcharge, so alternative methods are required. This paper discusses several cell-balancing methodologies. Active cell balancing methods remove charge from one or more high cells and deliver the charge to one or more low cells. Dissipative techniques find the high cells in the pack, and remove excess energy through a resistive element until their charges match the low cells. This paper presents the theory of charge balancing techniques and the advantages and disadvantages of the presented methods.

The increasing features and complexity of today's automotive architectures are becoming increasingly difficult to manage. Each new innovation typically requires additional mechanical actuators and associated electrical controllers. The sheer number of black boxes and wiring are being limited not by features or cost but by the inability to physically assemble them into a vehicle. A new architecture is required which will support the ability to add new features but also enable the Vehicle Assembly Plants to easily assemble and test each subsystem. One such architecture is a distributed multiplex arrangement that reduces the number of wires while enabling flexibility and expandability. Previous versions have had to deal with issues such as noise immunity at high switching currents. The LIN Bus with its low cost and rail-to-rail capability may be the key enabling technology to make the multiplexed architecture a reality.

Recent advances in dependable embedded system technology, as well as continuing demand for improved handling and passive and active safety improvements, have led vehicle manufacturers and suppliers to actively pursue development programs in computer-controlled, by-wire subsystems. These subsystems include steer-by-wire and brake-by-wire, and are composed of mechanically de-coupled sets of actuators and controllers connected through multiplexed, in-vehicle computer networks; there is no mechanical link to the driver. This paper addresses fundamental benefits and issues of steer-by-wire, especially those related to automated vehicle control and steering feel quality as perceived by the driver.

Hybrid electric vehicles have the potential to reduce air pollution and improve fuel economy without sacrificing the present conveniences of long range and available infrastructure that conventional vehicles offer. Hybrid vehicles are generally classified as series or parallel hybrids. A series hybrid vehicle is essentially an electric vehicle with an on-board source of power for charging the batteries. In a parallel hybrid vehicle, the engine and the electric motor can be used to drive the vehicle simultaneously. There are various possible configurations of parallel hybrid vehicles depending on the role of the electric motor/generator and the engine. In this paper, a comparative study of the drivetrains of five different hybrid vehicles is presented. The underlying design architectures are examined, with analysis as to the tradeoffs and advantages represented in these architectures.

The lateral runout of disc brake corner components can lead to the generation of brake system pulsation. Emphasis on reducing component flatness and lateral runout tolerances are a typical response to address this phenomenon. This paper presents the results of an analytical study that examined the effect that the attachment of the wheel to the brake corner assembly could have on the lateral distortion of the rotor. An analysis procedure was developed to utilize the finite element method and simulate the mechanics of the assembly process. Calculated rotor distortions were compared to laboratory measurements. A statistical approach was utilized, in conjunction with the finite element method, to study a number of wheel and brake corner parameters and identify the characteristics of a robust design.

This paper is an extension to the work presented in part I [1]. The control objective is still the same - use a logic based control design technique to assign a wheel slip, λ, to each corner of a vehicle, to track overall desired vehicle dynamics. As in part I, a fuzzy logic based controller is the primary control, with additional logic to select the inside/outside classifiers for the wheels. In part I, only the reduction of yaw rate error, e, was considered. It was shown that, although the overall system had satisfactory performance, there was slight deteriorization in the tracking performance when trying to compensate through a significant vehicle sideslip angle, β. In this paper, additional logic is introduced into the control to limit the vehicle sideslip angle, β; thus, allowing for a more robust desired yaw rate, Ωd, tracking control performance. The emergency lane change maneuver is simulated to show the effectiveness of the redesigned control.

Desiring to push thermoplastic poly-olefin (TPO) technology to its fullest limits and to confirm our position as the leader in the manufacturing of environmentally friendly TPO instrument panels, we have designed a process to manufacture 100% recycled instrument panel skins. This closed-loop process begins with extruding 100% recycled TPO flake into sheet stock to be painted and vacuum formed. The painted sheet is vacuum formed and the offal is ground into regrind flake, ready to be extruded again, thus completing the closed-loop process. This paper will describe a 100% closed loop recycling process for TPO instrument panels, discuss the intense validation process for recycled material and prove the robustness and durability of this interior solution.

Delphi Automotive Systems and BMW are jointly developing Solid Oxide Fuel Cell (SOFC) technology for application in the transportation industry primarily as an on-board Auxiliary Power Unit (APU). In the first application of this joint program, the APU will be used to power an electric air conditioning system without the need for operating the vehicle engine. The SOFC based APU technology has the potential to provide a paradigm shift in the supply of electric power for passenger cars. Furthermore, by supplementing the conventional fuel with reformate in the internal combustion engine, extremely low emissions and high system efficiencies are possible. This is consistent with the increasing power demands in automobiles in the new era of more comfort and safety along with environmental friendliness. Delphi Automotive Systems and BMW were successful in demonstrating an Auxiliary Power Unit (APU) based on Solid Oxide Fuel Cell (SOFC) technology in February, 2001.

Legal requirements and responsibility for the environment require improved recyclability of car components. This can be achieved by a reduction in the variety of materials used, which can be separated after use. This is being demonstrated for wiring harnesses using a new hook and loop based fastening system. Easier assembly and disassembly, elimination of fixation holes in the car body, and improved serviceability can lead to considerable cost reductions. Field experience on test cars will be available at a later date.

In recent years, a number of key influences are contributing to accelerate technological innovation in the automotive industrial sector. Concerns about renewable energy resource, fossil-fuels crises and higher gasoline prices, global warming awareness and environmental impacts, scarcity of minerals/metals and electronics demands rising are some of the major challenges for vehicle automakers and their suppliers. The interest in alternative fuel vehicles, especially hybrid-electrical vehicles (HEV) or renewable energy power concepts for road vehicles has become intensified and represents a significant area of research and development in order to meet nowadays global demands. However because of Hybrid Vehicles unique Power Supply System the electrical/electronic architecture (E/E) is sophisticated, requesting more robust sealing and a particular wiring harness components, such as connector, terminals and cables.

This paper provides a survey about the consequences of a 42V Power Supply System for new vehicle projects, specially, its impact on directed project for Emerging Markets. At a first moment, it will be described new systems and its demand for additional power availability for future projects, such as electrical steering and brake systems; electrical air conditioning compressor; and electrical water and oil pumps. Following this subject, it will be presented possible alternatives for 14/42V Power Supply Systems, and also its impact over Power and Signal Distribution System components, such as connector, terminals, cables, relays, electrical centers, etc. Finally, the previous presented scenarios will be analyzed under a point of view for the Emerging Market demand for such new proposed systems, looking for best alternative driven.

Delphi's Zero Resistance Technology (ZRT) is a revolutionary new product/process that enables the reduction of mass and volume from a traditional wiring assembly. ZRT is defined as a minimal (zero) resistance change over time. The ZRT product is an electrical/electronic connection system which provides a viable solution for high density and limited space wiring applications. The ZRT process is a semi-automated wiring harness manufacturing system with flexibility to produce harnesses to the customer demand.

In vehicular mobility context, it is extremely important for the environmental sustainability that the available energy will be used as efficiently as possible, both in the use of internal combustion engines (ICE) as powertrain, as well in the application of Hybrid and Electric Vehicle Motors (HEV/EV). In this comparison, ICE has a lower efficiency when compared to electric motors, wasting much of the potential energy of the fuel in form of heat and noise. On the other hand, the electric vehicles face limitation in autonomy and recharge time, demanding for a more efficient use of energy stored in batteries. This study aims to present emerging technologies for reuse of energy within the automotive context, originally known as “Energy Harvesting” and “Renewable Energies”.

Miniaturization is an important trend in many technology segments, once it can enable innovative applications generating new markets. This trend was begun in electronics industry after World War II and has spawned changes into automotive sector also. For Automotive Wiring Harness, miniaturization is clearly presented in most of the components, mainly because of its benefits like the potential of mass reduction, cost reduction and efficiency improvement. Furthermore the main voice of customer points to cable gauge reduction that represents a considerable challenge for connection manufacturing process due to quality control limitations presented by conventional crimp process for 0,35 [mm₂] cables and smaller. According to that, the scope of this article is to present, in details, a manufacturing process optimization for an alternative and more robust technology of joining copper stranded cables to tin brass terminals used on automotive wiring harness, Resistance Welding.

For A/C and cooling systems development is usual send vehicles to US or Europe for wind tunnel tests, witch is expensive and has a long lead-time. Here in Brazil Delphi has at the Piracicaba Technical Center a chamber equipped with temperature control and chassis dynamometer. There is a up-grade project for it that consist in add ducts with fans inside the chamber that will get air from the chamber, already in the right temperature, accelerate and homogenate the air flow and blow it out direct to the front end of the vehicle. For development purposes may be possible eliminate totally the necessity of sending vehicle abroad. It was then decided to use CFD simulation to predict firstly the required fan power necessary to supply winds until 120 km/h at the front end of the vehicle and secondly predict the airflow pattern inside the chamber, considering chamber inlet air, chamber outlet air, exhaust outlet, duct outlet and flow pattern around the vehicle.

An algorithm for estimation of vehicle yaw rate and side slip angle using steering wheel angle, wheel speed, and lateral acceleration sensors is proposed. It is intended for application in vehicle stability enhancement systems, which use controlled brakes or steering. The algorithm first generates two initial estimates of yaw rate from wheel speeds and from lateral acceleration. A new estimate is subsequently calculated as a weighted average of the two initial ones, with the weights proportional to confidence levels in each estimate. This preliminary estimate is fed into a closed loop nonlinear observer, which generates the final estimate of yaw rate along with estimates of lateral velocity and side slip angle. Parameters of the observer depend on the estimated surface coefficient of adhesion, thus providing adaptation to changes in road surface coefficient of adhesion.

Legal requirements, especially in the European Union, rising concern about our environment and economic reasons force us to look at End of Life Vehicles (ELV's) more critically. This paper describes some projects where recycling technologies have been developed showing clearly that recycling can be profitable. The projects demonstrate the recycling of Polyvinyl Chloride (PVC) insulation in automotive wiring, a separation technology for different plastic materials by melting point, the treatment of laminated materials like flexible printed circuits, some ideas of fastening systems, suited for disassembly and several basic rules for making recycling easier and profitable.