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The paper presents a model-based approach to testing embedded automotive software systems in a real-time. Model-based testing approach relates to a process of creating test artifacts using various kinds of models. Real-time testing involves the use of a real-time environment to implement test application. Engineers shall use real-time testing techniques to achieve greater reliability and/or determinism in a test system. The paper contains an instruction how to achieve these objectives by proper definition, implementation, execution, and evaluation of test cases. The test cases are defined and implemented in a modeling environment. The execution and evaluation of test results is made in a real-time machine. The paper is concluded with results obtained from the initial deployment of the approach on a large scale in production stream projects.

Shielding of the high voltage cabling is a cost effective method for reducing unwanted EMI in hybrid and electric vehicles. Ensuring the shielding effectiveness (SE) of the high voltage (HV) cabling and connectors is critical at the component and subsystem level. The effectiveness of the shielding must also be proven for the useful life of the vehicle. This paper will examine some of the critical aspects of ensuring good SE of HV cabling and connectors in hybrid and electric vehicles. This paper will also review some of the test methods utilized to make these measurements.

The presentation describes a technical solution for 100 Mbit/s Ethernet Data transmission cabling. This solution considers the specific requirements of automotive wiring harness and manufacturing. It bases on standard automotive connectors and headers. Currently the development of automotive electronic architecture considers central ECU or data backbone structure for the upcoming EE architecture (e. g. single ECU for network; SEN). For these structures solid and cost effective data backbone solutions are essential. Ethernet, a wide distributed and well-known bus system for office and industry data distribution provide a wide range of software tools and many physical layer solutions. Several cabling systems are available. Based on this we propose a solution for automotive application.

In hybrid and electric vehicles, the control of the electric motor is a critical component of vehicle functions such as motoring, generating, engine-starting and braking. The efficient and accurate control of motor torque is performed by the motor controller. It is a complex system incorporating sensor sampling, data processing, controls, diagnostics, and 3-phase Pulse Width Modulation (PWM) generation which are executed in sub-100 uSec periods. Due to the fast execution rates, care must be taken in the software coding phase to ensure the algorithms will not exceed the target processor's throughput capability. Production motor control development often still follows the path of customer requirements, component requirements, simulation, hand-code, and verification test due to the concern for processor throughput. In the case of vehicle system controls, typically executed no faster than 5-10 mSec periods, auto-coding tools are used for algorithm development as well as testing.

The propulsion system in most Electric Drive Vehicles (EDVs) requires an internal combustion engine in combination with an alternating current (AC) electric motor. An electronic device called a power inverter converts battery DC voltage into AC power for the motor. The inverter must be decoupled from the DC source, so a large DC-link capacitor is placed between the battery and the inverter. The DC-link capacitors in these inverters negatively affect the inverters size, weight and assembly cost. To reduce the design/cost impact of the DC-link capacitors, low loss, high dielectric constant (κ) ferroelectric materials are being developed. Ceramic ferroelectrics, such as (Pb,La)(Zr,Ti)O3 [PLZT], offer high dielectric constants and high breakdown strength. Argonne National Laboratory and Delphi Electronics & Safety have been developing thin-film capacitors utilizing PLZT.

As automotive and commercial vehicle OEM's continue their quest to reduce cost, product selection, quality, and reliability must be maintained. On-engine and wheel located connection systems create the greatest challenges due to the extreme levels of vibration. In the past, devices were fewer, and there where less direct connects in high vibration locations (Engine/ wheel sensors, electronic controllers, fuel injectors). Instead, small wire harnesses (“pigtails”) were commonly used. These pigtails can dampen the effect of the environment which includes mild to severe vibration by keeping the environmental effect away from the electrical connection contact point. Electrically connecting directly to the device creates new challenges in the connection system with the increased threat of fretting corrosion. Suppliers supporting OEM's are attempting to meet these direct connect requirements with lubrication, precious metal plating, and high contact force contacts.

The ultrasonic (US) welding of wires in automotive harnesses is increasingly used as an alternative to mechanical splices. However, this welding process may harm the electrical terminals crimped on the wires ends as a result on the energy propagation along the wire up the terminal with a frequency that is close to the terminals' natural frequencies. The modeling of the ultrasonic welding had been investigated by several authors from the process and weld strength perspective but the modeling of its effect on electrical terminals in automotive harnesses has not been given much attention in the literature. This paper describes and illustrates approaches used for modeling of the impact of the US welding on the electrical terminals in terms of stress and deformation from qualitative and quantitative perspectives and the related benefits/limitations from predictive standpoint. Illustrations are given on an actual terminal with respect to a typical ultrasonic welding process.

This study is concerned with quantitative analysis of the primary atomization, regarding the droplet size-velocity distribution function, of a multi-hole GDi plume through application of the Volume-of-Fluid Large Eddy Simulation (VOF-LES) method. The distinguishing feature of this study is the inclusion of an accurate seat /nozzle flow domain into the simulation. A VOF-LES study of the seat-nozzle flow and the near-field primary atomization of a single plume of a GDi multi-hole seat is performed. The geometry pertains to a purpose-built 3-hole GDi seat with three identical flow hole and counter-bore nozzles, arranged with 120° circumferential spacing. The VOF-LES prediction of the jet primary breakup structure and near-field macroscale is compared with spray imaging data. The droplet size and velocity distributions within a 4mm vicinity of the nozzle are analyzed. The results show production of a wide droplet size distribution through the jet primary atomization.

After the second worldwide oil crisis, Brazil put in place by 1975 a strategic plan to stimulate the usage of ethanol (from sugar cane), to be mixed to the gasoline or to be sold as 100% ethanol fuel (known as E100). To enable an engine to operate with both gasoline and ethanol (and their mixtures), by 2003 the “Flex Fuel” technology was implemented. By 2012 calendar year, from a total of about 3.8 million vehicles sold in the Brazilian market, 91% offered the “Flex Fuel” technology, and great majority used a gasoline sub-tank to assist on cold starts (typically below 15°C, where more than 85% of ethanol is present in fuel tank). The gasoline sub-tank system suffers from issues such as gasoline deterioration, crash-worthiness and user inconvenience such as bad drivability during engine warm up phase. This paper presents fuel injector technologies capable of rapidly electrically heating the ethanol fuel for the Brazilian transportation market.

During the evolution of Hybrid vehicles as well as electrical vehicles the need for an additional Voltage level was defined for the utilization of high power loads like electrical compressors, electrical heaters as well as power steering and electrical pumps. The main systems benefit is the generation of approximately 12 kW electrical power by a traditional belt driven Generator. This allows boost function for acceleration and recuperation for mild hybrid vehicles with the target to reduce up to 15% CO2 by keeping the traditional thermal based engines. Delphi has developed systems and components that meet the special 48 Volt related electrical requirements on arcing, hot plugging and corrosion. Our benefit is the long term expertise within the total system know how and the derived technical specification and needs.

In hybrid electric vehicles (HEVs) and full electric vehicles (EVs), efficient electrical power management with proper supply of power at the required voltage levels is essential. A DC (Direct Current)-DC converter is one of the key electrical units in a HEV/EV. The DC-DC converter dealt in the present work is intended to create the DC voltages necessary to power the accessories. The electronic circuit in this DC-DC converter consists of high power devices like Metal-Oxide Semiconductor Field-Effect Transistors (MOSFETs), inductors, transformers, etc. mounted on a printed circuit board (PCB). The DC-DC converter interacts with a high voltage battery pack and supplies a low voltage power to the accessory battery. Due to this power handling operation, the devices in the convertor experience high temperatures. The temperature rise of the devices beyond the permissible limits could be detrimental to an efficient and safe operation of the converter.

Advanced development engines are one-of-a-kind and expensive and generally have few, if any, spare parts available. These engines are particularly vulnerable to damage during control and calibration development due to unintended control actions from newly-generated algorithms, errant operator control commands, or lack of understanding of control limits for safe operation. Engine damage can result in significant program delays and expenses. Delphi is developing control systems and calibrations for the vehicle implementation of an experimental engine concept which incorporates a new high efficiency combustion process. Many of the algorithms within the control structure are new and untested, and therefore represent significant risk to these engines. The large amount of data displayed on computer test control screens makes human monitoring of all parameters nearly impossible, especially when display windows are layered on top of one another.

Most current flex-fuel vehicles are capable of operating on gasoline/ethanol blends from E0 to E85. The presence of gasoline in the fuel enables cold startability because some of its more volatile components can still vaporize at cold temperatures and produce an ignitable mixture. However when E100 is used, other means are required for cold starting because of ethanol's relatively low vapor pressure at low temperatures. A common technique is to employ an auxiliary gasoline fuel system for use only when temperatures are too low for the vehicle to start on E100 alone. But the added cost, complexity and maintenance of such systems have driven the search for a simpler approach. One such technique is to heat the fuel prior to injection. Fuel systems currently exist where heating occurs within the main conduit of the fuel rail. Another method is to heat the fuel within each fuel injector.

Over the past 20 years automobile quality, and consumer perceptions thereof, have been an increasing part of the vehicle engineering process. In automotive systems, torque-induced handwheel vibration is a significant source of consumer annoyance. When dealing with torque recordings containing a single or very small number of sinusoids, a time-referenced signal can easily be manipulated to yield instantaneous torque estimates. As the number of sinusoids (orders) grows, however, this becomes more difficult. In this paper, the authors demonstrate a simple technique to effectively estimate instantaneous torque level of high-order torque components when there are many higher-order sinusoids. The point is made that basic signal processing techniques applicable to time-referenced signals are also applicable to those referenced to angle or other variables.

High cell density (HCD) (≥ 600 cpsi) and /or ultra thin wall (UTW) (≤ 4 mil) extruded ceramic monolith substrates are being used in many new automotive catalyst applications because they offer (1) increased geometric surface area, (2) lower thermal mass, (3) increased open frontal area and (4) higher heat and mass transfer rates. Delphi has shown in previous papers how to use the effectiveness, NTU theory, to optimize the various benefits of these HCD / UTW catalysts. A primary disadvantage of these low solid fraction substrates is their reduced structural strength, as measured by a 3-D hydrostatic (isostatic) test. The weakest of these new substrates is only 10 to 20% as strong as standard 400 × 6.5 substrates. Improved converter assembly methods with lower, more uniform forces will likely be required to successfully assemble converters with such weak substrates in production.

Close coupled catalysts and new ceramic catalyst substrates have significantly improved the light-off performance of automotive converters required to meet stringent emission requirements. The hotter environment of these catalytic converters and the lower structural strength of the ceramic substrates require the rethinking of converter designs. The development of new package requirements to accommodate the change in environment and new substrates are discussed. A historical perspective on converter durability is presented as reference. Development of durability test protocols is essential to verifying product durability performance to these new environments. Data collection and documentation of testing templates are shown to demonstrate the effectiveness of tests that represent real world environments. Design improvements to address failure modes are discussed along with durability improvement results.