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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.

This paper investigates a method for improving vehicle stability by incorporating feedback from a yaw rate sensor into an electric power steering system. Presently, vehicle stability enhancement techniques are an extension of antilock braking systems in aiding the driver during vehicle maneuvers. One of the contributors to loss of vehicle control is the reduction in tactile feedback from the steering handwheel when driving on wet or icy pavement. This paper presents research indicating that the use yaw rate feedback improves vehicle stability by increasing the amount of tactile feedback when driving under adverse road conditions.

This paper is about the use of the Six Sigma Methodology, to solve variation problems in the manufacture area, at one of the Delphi Automotive Systems unit that manufacturer electrical harness. The DMAIC framework was followed, the improvements were done, eliminating the rots causes, and the use of Six Sigma methodology, was showed very efficient in solve problems. The methodology power, is in using a structured frame work, the DMAIC (Define-Measure-Analyze-Improve-Control), completing by quality quality tools (Pareto Chart, Five Why's, Cause and Effect Diagram) and statistical analyses, for example: variance analyses, hypotheses tests and Design of Experiments.

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.

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.

Several heater cores failed due to erosion by cavitation. After analysis, most of failures were explained by the presence of impurities in the heater core. It was then decided with the customer to use CFD simulation in order to prove that the cavitation was not caused by design concept of the tank. In this paper, we present the results of heater core simulations done in 2D and in 3D with Fluent. The objective is to simulate the pressure and velocity distribution within the heater core and to verify if the zones of low pressure are below the saturation vapour pressure of the fluid causing cavitation. In these areas, the deterioration of the tubes might occur due to erosion by cavitation.

In this study, US and UK accident data were analyzed to identify parameters that may influence rollover propensity to analyze driver injury rate. The US data was obtained from the weighted National Automotive Sampling System (NASS-CDS), calendar years 1992 to 1996. The UK pre-roll data was obtained from the national STATS 19 database for 1996, while the injury information was collected from the Co-operative Crash Injury Study (CCIS) database. In the US and UK databases, rollovers accounted for about 10% of all crashes with known crash directions. In the US and UK databases, most rollovers occurred when the vehicle was either going straight ahead or turning. The propensity for a rollover was more than 3 times higher when going around a bend than a non-rollover. In the UK, 74% of rollovers occurred on clear days with no high winds and 14% on rainy days with no high winds. In the US, 83% of rollovers took place in non-adverse weather conditions and 10% with rain.

This study compares the effect of US and European airbag deployments on injury outcomes for belted drivers in frontal crashes. Driver weight, height and seat track position was also examined in relation to those outcomes. This information may help to prioritize and guide the logic for “Smart” airbags. For the study, only airbag-equipped cars were considered. Two accident databases were used: 1) the weighted and unweighted National Accident Sampling System (NASS-CDS) from the US, calendar years 1995 to 1996, and 2) the unweighted Co-operative Crash Injury Study (CCIS) from the UK, calendar years 1992 to 1998. The parameters investigated were Injury Severity Score (ISS), Equivalent Test Speed (ETS), occupant weight, occupant height and seat location. For US drivers, the injury rate and occurrence were calculated using weighted data, while for UK drivers, the rate and occurrence were obtained using unweighted data.

The power steering valve plays a key role in the steering performance of a vehicle. It is desirable, therefore, to have a means of predicting valve performance for the development of the steering system. This paper describes a method of applying the orifice equation to a steering valve, along with the procedure for experimentally determining the flow coefficients for this equation. Data is provided which demonstrates the nature of change of the flow coefficients through the operating range of the valve. A method for accounting for these changes is provided, along with correlation results for measured and predicted valve performance.

Utilization of direct injection systems is one of the most promising technologies for fuel economy improvement for SI engine powered passenger cars. Engine performance is essentially influenced by the characteristics of the injection equipment. This paper will present CFD analyses of a swirl type GDI injector carried out with the Multiphase Module of AVL's FIRE/SWIFT CFD code. The simulations considered three phases (liquid fuel, fuel vapor, air) and mesh movement. Thus the transient behavior of the injector can be observed. The flow phenomena known from measurement and shown by previous simulation work [2, 7, 10, 11] were reproduced. In particular the simulations shown in this paper could explain the cause for the outstanding atomization characteristics of the swirl type injector, which are caused by cavitation in the nozzle hole.

The use of advanced electron microscopy techniques to characterize both the bulk and near-atomic level microstructural evolution of catalyst materials during different dynamometer/vehicle aging cycles is an integral part of understanding catalyst deactivation. The study described here was undertaken to evaluate thermally-induced microstructural changes which caused the progressive loss of catalyst performance in a three-way automotive catalyst. Several different catalyst processing variables, for example changing the washcoat ceria content, were also evaluated as a function of aging cycle and thermal history. A number of thermally-induced microstructural changes were identified using high resolution electron microscopy techniques that contributed to the deactivation of the catalyst, including sintering of all washcoat constituents, γ-alumina transforming to α-, β-, and δ-alumina, precious metal redistribution, and constituent encapsulation.

Bond wires are used in automotive electronic modules to carry current from external harness to components where flexibility under thermal cyclic loading is very essential between PCB (Printed Circuit Board) and connectors. They are very thin wires (few μm) made up of gold, aluminum or copper and have to undergo mechanical reliability to withstand extreme mechanical and thermal loads during different vehicle operation scenarios. Thermal reliability of bond wire is to make sure that it can withstand prescribed electric current under given boundary conditions without fusing thereby retaining electronic module's functionality. While carrying current, bond wire by virtue of its nature resists electric current flow and generates heat also called as joule heating. Joule heating is proportional to current flow and electrical resistance and if not handled properly can lead to thermal run away conditions.

The focus of this study is to validate the predictive capability of a recently developed physiology based thermal comfort modeling tool in a realistic thermal environment of a vehicle passenger compartment. Human subject test data for thermal sensation and comfort was obtained in a climatic wind tunnel for a cross-over vehicle in a relatively warm thermal environment including solar load. A CFD/thermal model that simulates the vehicle operating conditions in the tunnel, is used to provide the necessary inputs required by the stand-alone thermal comfort tool. Comparison of the local and the overall thermal sensation and comfort levels between the human subject test and the tool's predictions shows a reasonably good agreement. The next step is to use this modeling technique in designing and developing energy-efficient HVAC systems without compromising thermal comfort of the vehicle occupants.

This paper presents a simplified thermal model for round catalytic converters in steady state operation. Using this model, the analytic solution for the temperature distribution in the monolithic substrate is obtained. This analytic solution in the substrate is, then, combined with those in the intumescent mat [1] and the metal shell to obtain the temperature profile in the radial direction of the converter except for three unknown temperatures at the three material interfaces, which can be solved using an Excel application program. This analytical temperature solution facilitates the studies of the effects of various design parameters such as the exhaust gas temperature, exhaust gas flow rate, substrate cell geometry, converter dimensions, and ambient temperature and flow, etc.

Our customers expect in their vehicles the same constant connectivity that they experience in their homes through high speed internet portals. New services based on these advances will be transparent and ubiquitous - completely integrated into our lives, just as electricity comes to the wall socket or water from the faucet. The Wi-Fi Radio implements this vision using Wireless Fidelity (Wi-Fi) based on the suite of IEEE 802.11 standards. Drivers have constant wireless connectivity and personalized digital content made available to them through the Wi-Fi Radio. Ford and our partner Delphi developed the Wi-Fi Radio to overcome the inherent functional and packaging limitations of our vehicles, to quickly introduce new technology at affordable prices and to seamlessly integrate new services into the vehicle. We chose the radio as the integration site because the radio is accessible to every customer and affordable on every vehicle.

This study evaluates the comfort benefits of adjustable pedals by determining their effect on the distance between the occupant and steering wheel, occupant posture and foot kinematics. For the study, 20 volunteers were tested in a small and large vehicle equipped with adjustable pedals. Twenty volunteers were tested in a small and large vehicle at 3 pedal positions: normal, comfortable and maximum tolerable. In the small car, the decrease in ankle-to-steering wheel distance between the normal and comfortable position was higher in the short-statured group than the medium group. The mean change in chest-to-steering wheel distance was about 50 mm in the medium and in the order of 40 mm in the short group. The seatback angle increased by 2° in the medium group and decreased by 3° in the short group. In the large car, the decrease in ankle-to-steering wheel distance between comfortable and the normal position was about 70 mm in the short-statured and medium group.

In this paper, a theoretical model for the calculation of Specific Dissipation (SD) was developed. Based on the model, the effect of ambient and coolant radiator inlet temperatures on SD has been predicted. Results indicate that the effect of ambient and coolant inlet temperature variation on SD is small (less than 2%) when ambient temperature varies between 10 and 50°C and coolant radiator inlet temperature between 60 and 120°C. The effect of coolant flowrate on SD is larger if there is a larger flowrate variation. Experimental results indicate that a 1 % variation at 1.0 L/s will cause about ±0.6% SD variation. Therefore the flowrate should be carefully controlled.

This paper presents the objectives and preliminary results of the BRAKE project - a joint effort of Delphi Automotive Systems, Infineon Technologies, Volvo Car Corporation and WindRiver. The objective of this project is to use microelectronics technologies to design a distributed Brake-by-Wire system including: A distributed fault tolerant system for enhanced safety An extension of the OSEK based operating system for a distributed time triggered architecture An open interface between vehicle control, and brake system control The results comprise the requirements, interface specification (see [1]), a full simulation model, a hardware-in-the-loop bench, and a demonstration vehicle. The application has been developed using advanced automatic code generation for Infineon's TriCore based automotive microcontrollers.

Accurately predicting converter assembly deformation and mat pressure is essential in converter packaging design and manufacturing. In stuffing packaging, the annulus between the deformed shell and the catalyst is larger than that between the stuffing cone and the catalyst. As a result, the mat expands and undergoes unloading process. Tests show that the mat exhibits different loading and unloading characteristics. Using such a hysteresis mat pressure vs density curve in finite element analysis, the computed converter deformations closely agree with test data. Conversly, neglecting the mat hysteresis behavior may overestimate the deformation and pressure by a factor of three to four.

A recent trend within the automotive industry has been an emphasis on the development of modular assemblies for future vehicle applications. This trend has created a need for the development of methods to predict the performance of modules within the vehicle environment. In particular, the development of system models that account for the interactions between components within a modular assembly is necessary to insure that a module is properly designed. This paper describes a finite element system model of a damper module as installed in a McPherson strut front suspension. The modeling techniques used to construct the components within the modular assembly are discussed. The results of a study of the structural behavior of a damper module model subjected to quasi-static loading conditions are presented. Additionally, the effects of changes in individual component specifications on the overall system response are considered and the results are displayed.