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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.

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.

This paper first reports on the benchmarking of a gasoline- fueled vehicle currently for sale in California that is certified to ULEV standards. Emissions data from this vehicle indicate the improvements necessary over current technology to meet SULEV tailpipe standards. Tests with this vehicle also show emissions levels with current technology under off-cycle conditions representative of real-world use. We then present Delphi's strategy of on-board partial oxidation (POx) reforming with gasoline-fueled, spark-ignition engines. On-board reforming provides a source of hydrogen fuel. Tests were run with bottled gas simulating the output of a POx reformer. Results show that an advanced Engine Management System with a small on-board reformer can provide very low tailpipe emissions both under cold start and warmed-up conditions using relatively small amounts of POx gas. The data cover both normal US Federal Test Procedure (FTP) conditions as well as more extreme, off-cycle operation.

TPO is getting wider acceptance for automotive applications. An exterior application like a fascia is a very good example. Interiors are still a challenge due to many reasons including overall system cost. For interior applications, “all-olefin” means it mainly consists of three materials: TPO skin, cross-linked olefinic-based foam and PP substrate. The driving force for TPO in Europe is mainly recyclability while in the USA, it is long-term durability. This paper describes the key limitations of the current TPO systems which are: poor grain retention of TPO skin, shrinkage in-consistency of the skin, high cost of priming (or other treatments) and painting of the skin, lower process window of the semi-crystalline TPO material during thermoforming or In-mold lamination / Low pressure molding, high cost of the foam, low tear strength of the foam for deep draw ratio etc.

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.

In the catalytic converter, the thermal conductivity of the insulation material (intumescent mat) placed between the ceramic catalyst and the metal shell is strongly dependent on the temperature, resulting in the solving of non-linear heat conduction equations. In this paper, the analytic solution for the steady heat flow in a cylinder with temperature dependent conductivity is given. Using this analytic solution for the mat and including convection and radiation at the converter skin, an analytical expression for calculating converter skin temperature is obtained. This expression can be easily incorporated in a Fortran code to calculate the temperatures.

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.

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.

A Barometric Pressure Estimator (BPE) algorithm was implemented in a production speed-density Engine Management System (EMS). The BPE is a model-based, easily calibrated algorithm for estimating barometric pressure using a standard set of production sensors, thereby avoiding the need for a barometric pressure sensor. An accurate barometric pressure value is necessary for a variety of engine control functions. By starting with the physics describing the flow through the induction system, an algorithm was developed which is simple to understand and implement. When used in conjunction with the Pneumatic and Thermal State Estimator (PSE and TSE) algorithms [2], the BPE requires only a single additional calibration table, generated with an automated processing routine, directly from measured engine data collected at an arbitrary elevation, in-vehicle or on a dynamometer. The algorithm has been implemented on several different engines.

Balancing the fill sequence of multiple cavities in a rubber injection mold is desirable for efficient cure rates, optimized cure times, and consistent quality of all molded parts. The reality is that most rubber injection molds do not provide a consistent uniform balanced fill sequence for all the cavities in the mold - even if the runner and cavity layout is geometrically balanced. A new runner design technique, named “The Vanturi Effect”, is disclosed to help address the inherent deficiencies of traditional runner and cavity layouts in order to achieve a more balanced fill sequence. Comparative analysis of molded runner samples reveals a significant and positive improvement in runner and cavity fill balancing when the Vanturi Effect is integrated into the runner design.

The objective of this paper is to impart the challenges presented and the solutions derived to transform an artist's rendering into a production driver's door switch to be used in the interior of a high profile sports car. The challenges took many forms throughout the process, from data translation and packaging, to the final decorative issues. The results are a finished product providing a new approach to automotive interior switch design. It incorporates a low profile, continuous plane keypad with “soft touch” feel, tactile feedback, and integrated back lighting.

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.

Adaptive Cruise Control (ACC) technology is presently on the horizon as a convenience function intended to reduce driver workload. This paper presents an implementation of a brake algorithm, which extends the production cruise control feature. A brief overview of the system architecture and subsystem interfaces to the forward-obstacle detection system, throttle and engine management controls are described. Considerations of moding ACC with ABS and Traction Control are presented at the vehicle level. This development activity is presented in two major phases. Both phases of this development project utilize CAN controllers and transceivers to implement requirements for limited access highway driving. The initial phase of development requires the brake control to follow a deceleration command and operate “open-loop” to the vehicle controller. Vehicle test data capturing smooth stops on high coefficient surfaces is presented as insight to the braking performance of the vehicle.

A double dielectric barrier discharge reactor driven by an alternating voltage is a relatively simple approach to promote oxidation of NO to NO2 for subsequent reduction in a catalyst bed. The chemical performance of such a non-thermal plasma reactor is determined by its current and electric field behavior in the gap, and by the fraction of the current carried by electrons, because the key reactants which initiate the NO oxidation and accompanying chemical changes are produced there, mostly by electron impact. We have tried to determine by models and experiments the bounds on performance of double dielectric barrier reactors and guidelines for optimization. Models reported here predict chemical results from time-resolved applied voltage and series sense capacitor data.

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.

Electric power steering (EPS) is an advanced steering system that uses an electric motor to provide steering assist. Being a new technology it lacks the extensive operational history of conventional steering systems. Also conventional systems cannot be used to command an output independent of the driver input. In contrast EPS, by means of an electric motor, could be used to do so. As a result EPS systems may have additional failure modes, which need to be studied. In this paper we will consider the requirements for successful EPS operation. The steps required to develop diagnostics based on the requirements are also discussed. The results of this paper have been implemented in various EPS-based programs.

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.

This paper documents the advantages of brake corner system modeling and simulation over traditional component analysis techniques. A better understanding of the mechanical dynamics of the disc-braking event has been gained through brake corner system modeling and simulation. Single component analyses do not consider the load transfer between components during the braking event. Brake corner system analysis clearly quantifies the internal load path and load transfer sequence between components due to clearances or tolerance variations in the brake assembly. By modeling the complete brake corner assembly, the interaction between components due to the contact friction loads and variational boundary conditions can be determined. The end result permits optimal design of brake corner systems having less deflection, lower stress, optimum material mass, and reduced lead-time for new designs.

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.

Thermoplastic polyolefin (TPO) instrument panel skins are in demand in Europe and Asia as a solution to final product disposition environmental concerns. In North America TPO is valued for its durability characteristics (particularly heat and UV aging) and capability for deployment of seamless airbags at cold temperatures. Desiring to have an environmentally “green” system to create the “green” product, Delphi designed a manufacturing process with in-plant closed loop recycling of 100% offal directly back into the skin and the use of waterbased coating system for combating concerns with solvents. Delphi's development of recyclable TPO skin for instrument panels was introduced on 1997 production of Mercedes-Benz M-class. The paper will describe how the systems approach was used in overcoming the challenges involved in closed loop recycling of engineered offal during sheet manufacturing and thermoforming processes and the implementation of waterbased primer and topcoat systems.