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During the production controller and software development process, one critical step is the controller and software verification. There are various ways to perform this verification. One of the commonly used methods is to utilize an HIL (hardware-in-the-loop) test bench to emulate powertrain hardware for development and validation of powertrain controllers and software. A key piece of an HIL bench is the plant dynamics model used to emulate the external environment of a modern controller, such as engine (ECM), transmission (TCM) or powertrain controller (PCM), so that the algorithms and their software implementation can be exercised to confirm the desired results. This paper presents a 6-speed automatic transmission plant dynamics model development for hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software. The modeling method, model validation, and application in an HIL test environment are described in details.

This paper presents a hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software, with a focus on a closed-loop vehicle drive-train model incorporating a detailed automatic transmission plant dynamics model developed for certain applications. Specifically, this paper presents the closed-loop integration of a 6-speed automatic transmission model developed for our HIL transmission controller and algorithm test bench (Opal-RT TestDrive based). The model validation, integration and its application in an HIL test environment are described in details.

In this paper, a comparative study of the production applications of hybrid electric powertrains is presented. Vehicles studied include the Toyota Prius, Honda Insight, Toyota Estima, Toyota Crown, Honda Civic Hybrid, and Nissan Tino. The upcoming Ford Escape Hybrid and General Motors Parallel Hybrid Truck (PHT) will also be included, although advance information is limited. The goal of this paper is to look at what hybrid drivetrain architectures have actually been selected for production and what are the underlying details of these drivetrains. Since hybridizing a powertrain involves significant changes, the powertrain architectures are presented in diagram form, with analysis as to the similarities and advantages represented in these architectures. The specific hybrid functions used to save fuel are discussed. Peak power-to-weight ratio and degree of hybridization are plotted for the vehicles. System voltage versus electric power level are also plotted and analyzed.

Production software validation is critical during software development, allowing potential quality issues that could occur in the field to be minimized. By developing automated and repeatable software test methods, test cases can be created to validate targeted areas of the control software for confirmation of the expected results from software release to release. This is especially important when algorithm/software development timing is aggressive and the management of development activities in a global work environment requires high quality, and timely test results. This paper presents a hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software. The powertrain model used within the HIL consists of an engine model and a detailed automatic transmission dynamics model. The model runs in an OPAL-RT TestDrive based HIL system.

A key quantity for use in engine control is the exhaust manifold pressure. For production applications it is an important component in the calculation of the engine volumetric efficiency, as well as EGR flow and residual fraction. For cost reasons, however, it is preferable to not have to measure the exhaust manifold pressure for production applications. For that reason, it is advantageous to develop a model for estimating the exhaust manifold pressure in production application software that is small, accurate, and simple to calibrate. In this paper, a mean-value model for calculating the exhaust manifold pressure is derived from the compressible flow equation, treating the exhaust system as a fixed-geometry restriction between the exhaust manifold and the outlet of the tailpipe. Validation data from production applications is presented.

This paper presents an alternative brake that uses two floating discs, with four rubbing surfaces, to provide a step change improvement in performance over existing products. The paper details the development of this product highlighting the test data, which demonstrates the significant improvements in specific torque, fluid consumption and cooling rates. The design retains conventional materials, existing processes and fits within current package constraints. The sliding discs, which compensate for wear, allow opportunities to simplify the caliper to a fixed design and allow integration with the steering knuckle. Performance, refinement and durability test results indicate the current status of the design as implemented on a small passenger car and an SUV, and show its compatibility with existing vehicle brake control systems. Design options to implement this technology within current and future vehicle systems are also described.

The need for improved emissions control in lean exhaust to meet tightening, world-wide NOx emissions standards has led to the development of selective catalytic reduction of NOx with ammonia as a major technology for emissions control. Current systems are being designed to use a solution of urea (32.5 wt %) dissolved in water or Diesel Exhaust Fluid (DEF) as the ammonia source. While DEF or AdBlue® is widely used as a source of ammonia, it has a number of issues at low temperatures, including freezing below −12 °C, solid deposit formation in the exhaust, and difficulties in dosing at exhaust temperatures below 200 °C. Additionally creating a uniform ammonia concentration can be problematic, complicating exhaust packaging and usually requiring a discrete mixer.

Traffic engineers use time-of-day travel time databases to characterize normal travel times on roads. This information is used by traffic management centers together with information from sensors in the highway to identify problems and to make alternate route recommendations. In this paper, the travel time database concept is extended to a vehicle-to-vehicle communications network for traffic and safety information, wherein the travel time database is generated and stored by vehicles in the network, and used by the vehicles to identify abnormal traffic conditions. This infrastructure-free approach is attractive due to the potential to eliminate highway sensor and sensor maintenance costs, which are major factors that limit the growth of traffic information beyond major roadways in urban regions. Initial work indicates that database storage requirements in the vehicle should be manageable.

In this paper, we review existing software safety standards, guidelines, and other software safety documents. Common software safety elements from these documents are identified. We then describe an adaptable software safety process for automotive safety-critical systems based on these common elements. The process specifies high-level requirements and recommended methods for satisfying the requirements. In addition, we describe how the proposed process may be integrated into a proposed system safety process, and how it may be integrated with an existing software development process.

The perceived interior noise has been one of the major driving factors in the design of automotive interior assemblies. Buzz, Squeak and Rattle (BSR) issues are one of the major contributors toward the perceived quality in a vehicle. Traditionally BSR issues have been identified and rectified through extensive hardware testing. In order to reduce the product development cycle and minimize the number of costly hardware builds, however, one must rely on engineering analysis and simulation upfront in the design cycle. In this paper, an analytical and experimental study to identify potential BSR locations in a cockpit assembly is presented. The analytical investigation utilizes a novel and practical methodology, implemented in the software tool Nhance.BSR, for identification and ranking of potential BSR issues. The emphasis here is to evaluate the software for the BSR predictions and the identification of modeling issues, rather than to evaluate the cockpit design itself for BSR issues.

Implementation of engine turnoff at idle is desirable to gain improvements in vehicle fuel economy. There are a number of alternatives for implementation of the restarting function, including the existing cranking motor, a 12V or 36V belt-starter, a crankshaft integrated-starter-generator (ISG), and other, more complex hybrid powertrain architectures. Of these options, the 12V belt-alternator-starter (BAS) offers strong potential for fast, quiet starting at a lower system cost and complexity than higher-power 36V alternatives. Two challenges are 1) the need to accelerate a large engine to idle speed quickly, and 2) dynamic torque control during the start for smoothness. In the absence of a higher power electrical machine to accomplish these tasks, combustion-assisted starting has been studied as a potential method of aiding a 12V accessory drive belt-alternator-starter in the starting process on larger engines.

Embedded controllers and digital signal processors are increasingly being used in automotive safety critical control systems. Controller integrity is a significant concern in these systems. Over the past decade, several techniques have been published about controller safety and integrity verification. These techniques include: single processor with watchdog, dual processors, dual core processor, and asymmetric processor (intelligent watchdog). Each of these techniques have benefits, however, many new non-distributed safety-critical systems are applying the asymmetric processor technique to help verify controller integrity. This paper discusses an overview of five controller integrity techniques, and then provides a detailed discussion of an asymmetric processor approach. This paper presents two different options within the asymmetric processor approach.

Slush molding is a unique processing operation that was developed originally for polyvinyl chloride (PVC) based materials. It has been utilized to produce a variety of automotive interior products, including instrument panel skins, where relatively intricate designs are required. PVC becomes brittle upon aging, while thermoplastic polyolefin (TPO) doesn’t lose its ductility upon aging. TPOs have made significant inroads into interior applications in the form of thermoformed extruded sheet. However, when multiple grains, geometric (technical) grains, deep profile lettering, and logos are needed, slush molding is the preferred process. Currently, there is an increased demand for non-PVC slush moldable materials, such as TPO, that can meet these demanding aggressive styling requirements. The semi-crystalline nature of TPO compositions renders them more difficult to process than PVC in slush molding.

A comprehensive investigation into why gasoline fuel injectors fail in the field due to deposit formation has led to the development of a robust fuel injector design. Analysis of field failures provided critical clues as to why fuel injectors form deposits. The development of a repeatable test and a repeatable deposit forming fuel allowed the confirmation of these clues and the testing of design improvements. This combination of test cycle and fuel allowed for a reduced test time while providing sufficient sensitivity to differentiate between injector design improvements. Confirmation of design improvements was completed on a stationary vehicle using both commercially available gasoline and a formulated deposit forming fuel.

A study was conducted to investigate the effects of commercial E-85 fuel properties on Port Fuel Injector (PFI) durability performance. E-85 corrosivity, not lubricity, was identified as the primary property affecting injector performance. Relatively high levels of water, chloride and organic acid contamination, detected in commercial E-85 fuels sampled in the U.S. in 2006, were the focus of the study. Analysis results and analytical techniques for determining contaminant levels in and corrosivity of commercial E-85 fuels are discussed. Studies were conducted with E-85 fuels formulated to represent worst-case field fuels. In addition to contamination with water, chloride and organic acids, fuels with various levels of a typical ethanol corrosion inhibitor were tested in the laboratory to measure the effects on E-85 corrosivity. The effects of these E-85 contaminants on injector durability performance were also evaluated.

With the requirements for reducing the emissions and improving the fuel economy, the automotive companies are developing hybrid, 42 V and fuel cell vehicles. Power electronics is an enabling technology for the development of environmental friendly vehicles, and to implement the various vehicle electrical architectures to obtain the best performance. In this paper, the requirements of the power semiconductor devices and the criteria for selecting the power devices for various types of low emission vehicles are presented. A comparative study of the most commonly used power devices is presented. A brief review of the future power devices that would enhance the performance of the automotive power conversion systems is also presented.

The focus of this paper is to understand, from experimental data, the R134a refrigerant emission rates of various hose materials due to permeation. This paper focuses on four main points for hose assembly emission of R134a: (1) characteristics of hose permeation in response to the effect of oil in R134a and the characteristics of hose permeation of vapor vs. liquid refrigerant; (2) conditioning of the hose material over time to reach steady state R134a emission; (3) the relative contribution of hose permeation and coupling emission to the overall hose assembly refrigerant emission; (4) transient emission rates due to transient temperature and pressure conditions. Studies include hoses with different materials and constructions resulting in various levels of R134a permeation.

An analytical study of spray from an outwardly opening pressure swirl injector has been presented in this paper. A number of model injectors with varying design configurations have been used in this study. The outwardly opening injection process has been modeled using a modified spray breakup model presented in an earlier study. It has been observed that simulation results from the study clearly capture the mechanism by which an outwardly opening conical spray interacts with the downstream flow field. Velocity field near the tip of the injector shows that the conical streams emanating from an outwardly opening injector have the tendency to entrap air into the flow stream which is responsible for finer spray. A deviation from the optimum set of physical parameters showed a high propensity to produce large spray droplets. This study also emphasizes the importance of computational fluid dynamics (CFD) as an engineering tool to understand the complex physical processes.

A new single-brick Ba + alkali metals NOx-Trap catalyst has been developed to replace a two-brick NOx-Trap system containing a downstream three-way catalyst. Major development efforts include: 1) platinum group metals selection for higher HC oxidation with potassium-containing washcoat, 2) alumina and ceria selection, and Rh architecture design for more efficient NOx reduction and 3) NiO to suppress H2S odor. Mitsubishi Motors' 1.8L GDI™ with this Delphi new NOx-Trap catalyst with H2S control achieves J-LEV standard with less cost and lower backpressure compared to the previous model. It is further discovered that incorporation of NiO into the NOx-Trap washcoat is effective for H2S control during sulfur purge but has a negative impact on thermal durability and sulfur resistance. Further study to improve this trade-off has been made and preliminary results of an advanced washcoat design are presented in this paper. Details will be reported in a future publication.

Advances in wireless communications, model-based diagnostics, human-machine interfaces, electronics and embedded system technologies have created the foundation for a dramatic shift in the way the vehicles are diagnosed and maintained. These advances will enable vehicle diagnosis and maintenance to be performed remotely while the vehicle is being driven. There also has been recent strong consumer interest in Remote Diagnosis and Maintenance (RD&M). As a consequence, RD&M is drawing increased attention in the automotive industry. This paper provides the current status of vehicle remote diagnosis and maintenance, analyses the potential features of RD&M and their significance, and discusses how next generation automotive products could benefit from research and development in this area.