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The detection range of an air-fuel ratio sensor is expanded in the rich A/F region. Using a simulation technique, the limiting cause of the detection range in the rich A/F region is identified as insufficient combustion rates of CO and H2 with O2 on the electrode, which prevent realization of a limited diffusion state which is necessary to detect the air-fuel ratio. Applying an improved diffusion layer to decrease the diffusion rates and an improved electrode to increase the combustion rates, it is demonstrated that the detection limit can be expanded to λ=0.6 while that of a conventional sensor is λ=0.8.

Ten mold-in-color black polymers were evaluated for exterior weathering in an attempt to improve the specifications for exterior mold-in-color plastics to meet five year durability for a 95th percentile sunbelt customer. Four different weathering methods were utilized including Arizona exposure, Florida exposure, and Xenon arc exposures per the GMNA and the GM Europe methods. Colorfastness, gloss retention and other material property changes due to weathering were measured and analyzed against two GM durability standards. For the appearance attributes, correlations between actual exposure and accelerated exposure were attempted. Test results before and after polishing were also analyzed. Finally, in addition to comparing the performance of the ten polymers, the four weathering methods are compared and discussed with recommendations for the preferred testing regimen.

This paper presents the “Virtual Failure Mode and Effects Analysis (vFMEA)” system, which is a high-fidelity electrical-failure-simulation platform, and applies it to the software verification of an electric power steering (EPS) system. The vFMEA system enables engineers to dynamically inject a drift fault into a circuit model of the electronic control unit (ECU) of an EPS system, to analyze system-level failure effects, and to verify software-implemented safety mechanisms, which consequently reduces both cost and time of development. The vFMEA system can verify test cases that cannot be verified using an actual ECU and can improve test coverage as well. It consists of a cycle-accurate microcontroller model with mass-production software implemented in binary format, analog and digital circuit models, mechanical models, and a state-triggered fault-injection mechanism.

“Virtual Failure Mode and Effects Analysis” (vFMEA), a novel safety-verification method of control software for automotive electronic systems, was proposed to save prototyping cost at verification stage. The proposed vFMEA is system-level FMEA method, which uses virtualized electronic control units (ECUs) consisting of microcontroller models on a microcontroller simulator and a transistor-level circuit models on a circuit simulator. By using the structure, the control software in binary code formats can be verified when a circuit-level fault occurs in the ECU hardware. As an illustrative example, vFMEA was applied to an engine ECU. As a result of short-circuit fault into a driver IC, engine revolution and engine speed decreased. However, the engine continued to operate normally when an open-circuit fault occurred in a capacitor connected in parallel. Effects of the hardware faults in ECU on a vehicle are demonstrated; thereby software verification can be performed using vFMEA system.

We have developed a full virtual engine system prototyping platform with 4-cylinder engine plant model, SH-2A CPU hardware model, and object code level software including OSEK OS. The virtual engine system prototyping platform can run simulation of an engine control system and digital knock detection system including 64-pt FFT computations that provide required high-resolution DSP capability for detection and control. To help the system design, debugging, and evaluation, the virtual system prototyping consists of behavior analyzer which can provide the visualization of useful CPU internal information for control algorithm tuning, RTOS optimization, and CPU architecture development. Thus the co-simulation enables time and cost saving at validation stage as validation can be performed at the design stage before production of actual components.

Electromagnetic compatibility (EMC) is becoming more important in power converters and motor drives as seen in hybrid electric vehicles (HEV) to achieve higher reliability of the vehicle and its components. Electromagnetic interference (EMI) of the electronic components for a vehicle are evaluated and validated at a component-level test bench; however, it is sometimes observed that the EMI level of the components can be changed in a vehicle-level test due to differences in the vehicle's configuration (cable routing, connecting location etc.). In this presentation, a vehicle-level EMC simulation methodology is introduced to estimate radiated emissions from a vehicle. The comparison between the simulation and measurement results is also presented and discussed.

This paper presents an experimental comparative study between the OCTOGONAL-Gate Silicon-on-Insulator (SOI) nMOSFET (OSM) and the conventional SOI nMOSFET (CSM) considering the same bias conditions and the same gate area (AG), in order to verify the influence of this new MOSFET layout style to handle high current for automotive modules. Analog integrated circuits (ICs) design tends to be considered an art due to a large number of variables and objectives to achieve the product specifications. The designer has to find the right tradeoffs to achieve the desired automotive specification such as low power, low voltage, high speed and high current driver. SOI MOSFET's technology is required to provide the growth of embedded electronics. This growth is driving demand for power-handling devices that are smaller yet still provide high current driver capabilities.

Often components or subsystems are attached to other systems through multiple fasteners at multiple locations. Examples may include things like compressors, alternators, engine cradles, powertrain mounting systems, suspension systems, body structures or almost any other interface between components or subsystems. Often during early design stages, alternative component or subsystem configurations are being considered that can have very different interface characteristics, such as alternators with different number of mounting fasteners, or suspension systems with different number of body structure interface attachments. Given these different mounting configurations, it can be difficult to meaningfully compare the interface performance of the two components or subsystems.

Interior permanent magnet machines are being widely used in hybrid vehicles owing to their compact size and high power density. Vehicle level application requires the motor to operate at high speed beyond the base speed of the motor. This is accomplished through flux weakening control. Nonfunctioning of inverter switches and/or gate driver circuit during flux weakening could give rise to a potential fault scenario called Un-Controlled Generation (UCG). This paper gives a detailed background of UCG and its impact on the high voltage and propulsion systems. In further sections the details related to modelling and analysis of UCG will be discussed. Finally, the paper will conclude with simulation results and comparison of the results with motor dynamometer test data.

Safety critical systems are taking demands on automotive systems where the distributed embedded system needs a communication system with properties of fault tolerant real-time communication. In order to increase reliability of systems with serial communication, a device called bus guardian can be added on physical layer to perform management of schedules and data independently from the communication controller, monitoring timing and sending signals of bus status notifying error occurrences to the host. The goal of this paper is to present and perform a comparative analysis of different strategies of bus guardian used in CAN, TTP/C and Flexray protocols, applied in safety critical system in automobile domain. A comparison was carried out to describe the properties and application for each protocol.

Predicting the vibration of a motor gearbox assembly driven by a PWM inverter in the early stages of development is demanding because the assembly is one of the dominant noise sources of electric vehicles (EVs). In this paper, we propose a simulation model that can predict the transient vibration excited by gear meshing, reaction force from the mount, and electromagnetic forces including the carrier frequency component of the inverter up to 10 kHz. By utilizing the techniques of structural model reduction and state space modeling, the proposed model can predict the vibration of assembly in the operating condition with a system level EV simulator. A verification test was conducted to compare the simulation results with the running test results of the EV.

With rapid increase of vehicles on the road, safety concerns have become increasingly prominent. Since the leading cause of many traffic accidents is known to be by human drivers, developing autonomous vehicles is considered to be an effective approach to solve the problems above. Although trajectory tracking plays one of the most important roles on autonomous driving, handling the coupling between trajectory-tracking control and ESP under certain driving scenarios remains to be challenging. This paper focuses on trajectory-tracking control considering the role of ESP. A vehicle model is developed with two degrees of freedom, including vehicle lateral, and yaw motions. Based on the proposed model, the vehicle trajectory is separated into both longitudinal and lateral motion. The coupling effect of the vehicle and ESP is analyzed in the paper. The lateral trajectory-tracking algorithm is developed based on the preview follower theory.

Future automobiles are required to support an increasing number of complex, distributed functions such as active safety and X-by-wire. Because of safety concerns and the need to deliver correct designs in a short time, system properties should be verified in advance on function models, by simulation or model checking. To ensure that the properties still hold for the final deployed system, the implementation of the models into tasks and communication messages should preserve properties of the model, or in general, its semantics. FlexRay offers the possibility of deterministic communication and can be used to define distributed implementations that are provably equivalent to synchronous reactive models like those created from Simulink. However, the low level communication layers and the FlexRay schedule must be carefully designed to ensure the preservation of communication flows and functional outputs.

Magnetic Phase Shifter is the controlling element to make integral action, excellent in anti-noise performance and makes high stable and reliable controlling device. (1)* We have developed a new compact thyristor chopper equipment controlled by Magnetic Phase Shifter. This equipment has simple controlling circuit and many functions such as wide range duty factor control, adjustable plugging brake, speed up by field weakening, anti-rollback control and so on.

There are now a wide variety of Hybrid and Electric Vehicles in or near production. They reduce or displace petroleum consumption with of various combinations of conventional IC engine, mechanical transmission, liquid fuel storage, electrical energy storage, electrical and electro-mechanical energy conversion, and vehicle-to-grid energy interface. These Electrified types of vehicles include Mild Hybrid, Full Hybrid, Plug-In Hybrid, Extended Range Electric, and Battery Electric. Some types differ in their actual usability for the real mixes of driving trips, and further that differ in their effectiveness to reduce or displace fuel in actual real world driving use. Vehicle size is also a factor in total vehicle utility in transporting people. If we may segment drivers by their driving needs, in each segment, we see a particular type of electrified vehicle that is better suited than others at minimizing fuel cost and petroleum consumption for the purposes of transporting people.

The role of sensors and sensing technologies for the next generation vehicle systems are discussed. The control systems for engines and power-train are expected to realize high efficiency with low pollution and comfort drivability. Vehicular safety and chassis control systems are expected to avoid many kinds of traffic accidents caused by the human errors of drivers. Vehicular information systems will help the drivers to get the information to manage their vehicles economically and efficiency. In every system mentioned above, sensors and sensing technologies are playing an increasingly important role. This paper introduces and discusses essential technologies for sensors and sensing which can be expected to bring the solutions to the future automotive systems.

The Chevrolet Volt is an electric vehicle (EV) with extended-range (ER) that is capable of operation on battery power alone, and on power generated by an on-board gasoline engine after depletion of the battery charge. For 2016, GM has developed the next generation of the Volt vehicle and “Voltec” propulsion system. Building on the experience of the first generation Volt, the second generation targeted improved all-electric range, improved charge sustaining fuel economy, and improved performance. All of this was to be accomplished while maintaining the EV character of the first generation Volt which customers clearly valued. This paper describes the next generation “Voltec” system and the realized improvements in efficiency and performance. The features of the propulsion system components, including energy storage, transaxle, electric motors and power electronics, on-board charging, and engine are described and compared with the previous generation.

The intention of this paper is to discuss the importance of analysis of some electrical parameters in order to design analog circuits in electronic modules, including automotive ones. Today, the challenge is to have devices which consume less power, high performance and higher integration density, so that it explains why such analysis is crucial to achieve better performances and meet the desired results.

It has the aim to discuss the evolution of electronics components, integrated circuits, new transistors concepts and associate its importance in the automotive modules. Today, the challenge is to have devices which consume less power, suitable for high-energy radiation environment, less parasitic capacitances, high speed, easier device isolation, high gain, easier scale-down of threshold voltage, no latch-up and higher integration density. The improvement of those characteristics mentioned and others in the electronic devices enable the automotive industry to have a more robust product and give the possibility to integrate new features in comfort, safety, infotainment and telematics modules. Finally, the intention is to discuss advanced structures, such as the silicon-on-insulator (SOI) and show how it affects the electronics modules applied for the automotive area.

Quasi-static tensile properties of TRIP590 steels from three different manufacturers were investigated using digital image correlation (DIC). The focus was on the post-uniform elongation behavior which can be very different for steels of the same grade owing to different manufacturing processes. Miniature tensile specimens, cut at 0°, 45°, and 90° relative to the rolling direction, were strained to failure in an instrumented tensile stage. True stress-true strain curves were computed from digital strain gages superimposed on digital images captured from one gage section surface during tensile deformation. Microstructural phases in undeformed and fracture specimens were identified with optical microscopy using the color tint etching process. Fracture surface analyses conducted with scanning electron microscopy and energy dispersive spectroscopy were used to investigate microvoids and inclusions in all materials.