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While the potential emissions and efficiency benefits of HCCI combustion are well known, realizing the potentials on a production intent engine presents numerous challenges. In this study we focus on identifying challenges and opportunities associated with a production intent cam-based variable valve actuation (VVA) system on a multi-cylinder engine in comparison to a fully flexible, naturally aspirated, hydraulic valve actuation (HVA) system on a single-cylinder engine, with both platforms sharing the same GDI fueling system and engine geometry. The multi-cylinder production intent VVA system uses a 2-step cam technology with wide authority cam phasing, allowing adjustments to be made to the negative valve overlap (NVO) duration but not the valve opening durations. On the single-cylinder HVA engine, the valve opening duration and lift are variable in addition to the NVO duration. The content of this paper is limited to the low-medium operating load region at 2000 rpm.

A high pressure outwardly opening fuel injector has been developed to produce sprays that meet the stringent requirements of gasoline direct injection (DI) combustion systems. Predictions of spray characteristics have been made using KIVA-3 in conjunction with Star-CD injector flow modeling. After some modeling iterations, the nozzle design has been optimized for the required flow, injector performance, and spray characteristics. The hardware test results of flow and spray have confirmed the numerical modeling accuracy and the spray quality. The spray's average Sauter mean diameter (SMD) is less than 15 microns at 30 mm distance from the nozzle. The DV90, defined as the drop diameter such that 90% of the total liquid volume is in drops of smaller diameter, is less than 40 microns. The maximum penetration is about 70 mm into air at atmospheric pressure. An initial spray slug is not created due to the absence of a sac volume.

Engine tests were conducted to study the effect of fuel-air mixture preparation on the combustion and emission performance of a two-stroke direct-injection engine. The in-cylinder mixture distribution was altered by changing the injection system, injection timing, and by substituting the air in an air-assisted injector with nitrogen. Two injection systems which produce significantly different mixtures were investigated; an air-assisted injector with a highly atomized spray, and a single-fluid high pressure-swirl injector with a dense penetrating spray. The engine was operated at overall A/F ratios of 30:1, where stratification was necessary to ensure stable combustion; and at 20:1 and 15:1 where it was possible to operate in a nearly homogeneous mode. Moderate engine speeds and loads were investigated. The effects of the burning-zone A/F ratio were isolated by using nitrogen as the working fluid in the air-assist injector.

Brazilian automotive market has been growing faster than ever. In order to react properly to market increasing demand in terms of volume and diversity, production systems have to be carefully designed. Traditional manufacturing tends to react to demand increase by outsourcing or investing in new equipments or facilities. Lean thinking suggests that by reducing waste along the value stream it is possible to increase flexibility and freed resources to reduce the investment level required to cope customer’s needs. This paper presents two cases of a system redesign based on the lean manufacturing principles to support the demand.

Short timing and complexes strategies are mandatory in a competitive market as automotive industry. Therefore quality problems identification during and after the coding phase, may be the difference between the business success and undesired conflicts with customer, solving problems that were not previously identified. Consequently the usage of technique Mahalanobis Taguchi System (MTS) to analyze coding metrics, create an environment to improve the final product quality and mitigate potential problems later identified.

Many companies around the world have adopted the lean thinking as their strategy to operate, in a global market where changes happen all the time. One foundation for the success of lean manufacturing appliance is the continuous improvement approach which has been considered even on company statements, or it can be also considered as part of the genetic code of any enterprise. However, if in one side the continuous improvement thinking, set people mind to look for opportunities of improvement all the time, on other hand these improvements are incremental and they do not have significant impact on company performance on both short-term and medium-term and sometimes, the activities performed by the employees are not sustainable due to the lack of structure to manage and follow up these activities.

The utilization of Laser welding process has increased during last years in several areas of industry, due to many benefits that can be achieved with this technology, such as: flexibility, productivity and quality. Thus, the optimization of Laser welding processes has been considered as a “green field” to be explored by Laser manufacturers, automation companies and process/project engineers. Nowadays there are few researches that provide a roadmap for Laser welding processes improvement that approaches both the aspects and characteristics applied to evaluate the Laser weld application performance. Therefore, this paper has per its main purpose through an exploratory study to provide parameters toward continuous improvement of Laser welding process considering both types of Lasers: Laser spot weld and Laser seam weld of stainless steel joints, thus this work may be considered as theoretical and practical reference to be applied by people involved with Laser welding applications.

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.

This paper presents a theoretical and experimental study of a cylinder deactivation valvetrain system for the integration into an Engine Management System (EMS). A control-oriented lumped parameter model of the deactivation valvetrain system is developed and implemented using Matlab/Simulink, and validated by experimental data. Through simulation and experimental data analysis, the effect of operating conditions on the dynamic response is captured and characterized, over a wide range of operating conditions. The algorithm provides a basis for the calibration of the deactivation hardware. The generic characterization of the dynamic response can simplify the calibration parameters for the implementation in engine management systems.

This paper describes an environment for the development of production Engine Management Systems (EMS). This includes a formal framework and modeling methodology. The environment is based on using Simulink/Stateflow for developing a control system executable specification and a plant model. This allows for simulations of the system to be performed at the engineer's desk, which is identical performance with production software. We provide the details for incorporating production legacy code into the Simulink/Stateflow control system. The system includes a multi-rate, and event driven operating system. This system is developed to facilitate new algorithm development and automated software testing. Based on Simulink/Stateflow this specification will be suitable for use with commercial automatic code generation tools.

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.

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.

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.

A parametric study on the effects of critical injector design parameters of inwardly-opening pressure-swirl injectors was carried out using 3-D internal flow simulations. The pressure variation and the integrated momentum flux across the injector, as well as the flow distributions and turbulence structure at the nozzle exit were analyzed. The critical flow effects on the injector design identified are the swirler efficiency, discharge coefficient, and turbulence breakup effects on the spray structure. The study shows that as a unique class of injectors, pressure-swirl injectors is complicated in fluid mechanics and not sufficiently characterized or optimized. The swirler efficiency is characterized in terms of the trade-off relationship between the swirl-to-axial momentum-flux ratio and pressure drop across the swirler. The results show that swirl number is inversely proportional to discharge coefficient, and that hole diameter and swirler height is the most dominant parameters.

Although the Six Sigma [1] concept has become very popular in industrial sectors, very little is said about how to start a successful implementation in a Corporation, or when it should be initiated, and the most important, who should be addressed to lead this task. Its methodologies are widely observed by different sectors of the automotive market, typically focusing in projects with a potential financial impact, following the DMAIC sequence. More than just financial return, this sophisticated tool, has a direct impact on Quality in different levels for both non-productive process and manufacturing process, that eventually would also affect some organizational structures that ultimately can be understood as reengineering.

In recent years, the desire for improved vehicle performance, reliability and safety have increased the electrical content and its complexity in vehicles. Advanced automotive systems integrate sensors, controllers, actuators and communication networks. To maintain safety and reliability, a comprehensive system of diagnostics and physical and analytic redundancy are used. In some cases, diagnostic strategies based on analytical redundancy can provide detection, as well as fault-tolerance, and may provide benefits in cost, packaging, flexibility and reusability. This paper discusses a range of diagnostic methods and their applicability to advanced automotive systems such as X-by-Wire. It will also show the reduction to practice of an advanced analytical technique for an automotive application.

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.

Delphi is developing a new combustion technology called Gasoline Direct-injection Compression Ignition (GDCI), which has shown promise for substantially improving fuel economy. This new technology is able to reuse some of the controls common to traditional spark ignition (SI) engines; however, it also requires several new sensors and actuators, some of which are not common to traditional SI engines. Since this is new technology development, the required hardware set has continued to evolve over the course of the project. In order to support this development work, a highly capable and flexible electronic control system is necessary. Integrating all of the necessary functions into a single controller, or two, would require significant up-front controller hardware development, and would limit the adaptability of the electronic controls to the evolving requirements for GDCI.

The development of an analytical model for multilayer stack subjected to temperature change is demonstrated here. Thin continuous layers of materials bonded together deform as a plate due to their differing coefficients of thermal expansion upon subjecting the bonded materials to the change in temperature. Applications of such structures can be found in the electronics industry (the study of warpage issues in printed circuit boards) or in the aerospace industry as (the study of laminated thin sheets used as skin structures for load bearing members such as wings and fuselage). In automotive electronics, critical high-power packages (IGBT, Power FETs) include several layers of widely differing materials (aluminum, solder, copper, ceramics) subjected to wide temperature cyclic ranges. Modeling of such structures by using three-dimensional finite element methods is usually time consuming and may not exactly predict the inter-laminar strains.

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.