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Alcohol-related collisions cause numerous deaths and injuries. The purpose of this paper is to review the technological changes that could be made and are being made that could reduce rates of impaired driving collisions. These can be classified into four categories: 1) interlock systems based on testing drivers’ blood alcohol concentration, 2) systems for monitoring driver behaviors such as head and eye or pupil movements, 3) systems that monitor vehicle dynamics and behavior, and 4) remote detection and stopping vehicles technologies. Each of these technologies has some efficiency and uses and varying levels of social and individual acceptance. Innovation may come from looking at novel ways of combining these technological designs to achieve targets to reduce the devastating effects of impaired driving for many communities.

One main challenge during the validation of automotive communication architectures is to consider the assembled system and more especially the interactions between the different components. We propose in this work a test and validation infrastructure based on tightly coupled co-simulation and prototype platforms. The co-simulation framework, on one hand, enables the efficient simulation of the entire network and the accurate analysis of the communication at different abstraction layers. On the other hand, the prototype framework is required for the model calibration and for the system validation on a realistic environment. We discuss further how the interconnection of these two platforms supports the analysis of both single components and entire communication networks. Experimental results illustrate our approach.

Safety is a requirement concerning an increasing number of automotive applications. Recent safety standards set requirements for designing safety-critical systems. Among others, these specifications include a comprehensive detection and handling of hardware faults. Currently emerging dual-core microcontrollers provide a cost-effective opportunity to fulfill these requirements. In this paper we analyze a safety-critical application example and discuss two different approaches, an application-specific approach and a generic approach for implementing functional safety requirements on a dual-core microcontroller. An investigation of the associated concepts called function monitoring architectures and generic architectures reveals their differences and at the same time advantages and disadvantages. Besides effects on safety, effects on reliability, modifiability and costs are evaluated and presented graphically.

There was concern that a variable compression ratio engine fitted with a multi-link mechanism might produce louder booming noise due to the inertial forces caused by the lateral swing of the links. Accordingly, a relational expression between the inherent characteristics of the links was found to counterbalance those forces. As a result, it was found that a multi-link VCR engine designed on the basis of this link concept showed lower levels of horizontal excitation forces similar to the reduction of vertical forces. This suggests that, even without any add-on devices like a balance shaft, the engine can achieve the same level of booming noise performance as conventional engines. In addition, this new link concept obtained as a result of this study is expected to be effective in reducing higher-order interior noise as well.

Given the increased use of programmable embedded electronic systems (PEES) in automotive applications and their vital importance, it is not only important for engineers to design PEES in such a way to meet or exceed safety requirements but also quantify how “safe” these systems are. At the University of Virginia's Center for Safety-Critical Systems, we have developed a safety quantification methodology for embedded real time safety-related systems. The goal of the safety quantification methodology is to provide a generic but rigorous and systematic way of characterizing the dependability behavior of embedded systems that is applicable to a broad range of applications from automotive to nuclear. This paper presents a quantitative safety assessment methodology for safety-critical embedded systems using fault injection (FI). This methodology has been developed, refined and applied to a number of commercial safety-grade systems in the railway, nuclear and avionics industries.

Software has rapidly gained importance as a driver for innovation in automobiles. Since many safety-related automotive systems make intensive use of software, the upcoming ISO 26262 poses several requirements addressing software development, including safety analyses for software. For software, however, safety analysis techniques are seldom applied in practice. It is unclear how to apply them and in many cases even their usefulness in general is questioned. This article illustrates why software safety analyses are indispensable, how they can be efficiently applied to complex systems, and how they relate to existing software quality assurance techniques and system safety analyses.

With the increased adoption of AUTOSAR operating systems across the different automotive system domains a notable exception has been that of the safety critical systems. This domain has strict requirements on precise requirements capturing, proven design flow, robust implementation, exhaustive testing, detailed documentation and traceability, and project management processes. These requirements are normally prohibitive to adopt for commercial ‘one size fits all’ solutions due to the huge expense and resources required to meet such a strict regime. So under these constraints AUTOSAR is far from a perfect fit for safety systems. Nonetheless, the attractive features of reuse and portability still make AUTOSAR based systems highly desirable.

Through the use of hybrid technology, Ford Motor Company continues to realize enhanced vehicle fuel economy while meeting customer performance and drivability targets. As is characteristic of all Ford Hybrid Electric Vehicles (HEVs), the basis for resolving these competing requirements resides with its Vehicle System Control (VSC) strategy. This strategy implements complex high-level executive controls to coordinate and optimize the desired operational state of the major HEV powertrain subsystems. To ensure that the VSC software meets its intended functionality, a software validation process developed at Research and Advanced Engineering has been integrated as part of the vehicle controls development process. In this paper, this VSC software validation process implemented for a next generation hybrid powertrain is presented. First, an overview of the hybrid powertrain application and the VSC software architecture is introduced.

Failure Modes and Effects Analysis (FMEA) is a well established safety analysis technique used for the assessment of safety critical engineering systems in the automotive industry. Although FMEA has been shown to be useful, the analysis is typically restricted to the effects of single component failures; even partial analysis of combinations or sequences of multiple failures is in practice considered too complex, laborious and costly to perform. In this paper, we describe a new technique in which FMEAs are semi-automatically built from the topology of a system and component-level specifications of failure data. The proposed technique allows an extended form of “combinatorial & sequential FMEA” in which assessment of the effects of combinations and sequences of failures becomes feasible and cost effective.

Operator error is a primary cause of vehicle accidents, yet human ingenuity is critical to effectively react in situations automation is not prepared to handle. Human operators have always been the ultimate authority, but their decisions may or may not be safe. This paper explores the constraints and requirements of vehicle systems that support automation override of a human operator. We adopt the view that a human operator remains the ultimate authority until grave risk is encountered, at which time the automation overrides strictly to re-establish a safe operating state. An override system must continually monitor vehicle state, predict near-term risk levels, compute a strategy to mitigate substantial risk, and warn the operator of the impending risk given sufficient time. Override action must occur just-in-time to re-establish a safe state before risk increases beyond the “grave” threshold.

Model-based software development and automatic code generation have become increasingly established in recent years. The automotive industry has widely adopted and successfully deployed these methods in many different series production programs worldwide. This brought various benefits, such as a reduction in development times, improved quality due to more precise specifications, and early verification and validation by means of simulation. At the same time, more and more safety-related and safety-critical systems have been - and will be -introduced into modern vehicles. Common examples are active front steering, adaptive cruise-control, and integrated chassis control. This leads to the question, if and how model-based design and automatic production code generation can be applied to the development of safety-critical systems.

The design of a cost-effective SIL3/ASILD-compliant failsafe computer control system is a great challenge because of the requirements of IEC 61508 and/or ISO CD 26262. In this paper the formal design methods in concept, space, time, and function domains are presented, which are used for the development of a failsafe chassis control system. We discuss the generic failsafe system architectures based on one-core and multi-core μCs in the framework of Markov’s safety model, and associated safety metrics like DC, SFF, and PFH. The safety aspects require that, a safety-related system is validated by an adequate safety analysis method. For this purpose a new integrated FMEDA (iFMEDA) for the validation of a safety-related vehicle application system is briefly introduced. Finally, the use of safety concepts for failure monitoring in practice chassis applications and generic diversity algorithms is shown.

High sensitivity and capacity thin film pressure sensors using the piezoresistive effect of ytterbium (Yb) thin films have been developed on metal plates using semiconductor manufacturing technology. The pressure sensors can effectively operate in the temperature range of −30 °C to 120 °C due to the thermally stable polycrystalline phase of ytterbium thin films. The sensors clamped at bolted joints on body mounts show excellent dynamic response comparable to that of a load cell.

An experimental investigation of combustion cycle-by-cycle stability under cold idling conditions has been carried out on a Dl diesel to examine the influence of pilot fuel injection strategy. The engine is a single cylinder variant of a multi-cylinder design meeting Euro 4 emissions requirements. The engine build had a swept volume of 500cc and a compression ratio of 18.4:1. Work output and heat release characteristics have been investigated at test temperatures of 10, 0, −10 and −20°C and speeds in the range from 600 to 1400rpm. At the lowest temperature, −20°C, stability is sensitive to the timing of main injection and is prone to deteriorate with increasing engine speed. The influence of the number of pilot injections and pilot fuel quantity on stability has been explored. Best stability was achieved by increasing the number of pilot injections as temperature is lowered, from one at 10°C to two at −10°C and between two and four at −20°C.

A new hybrid transmission has been developed for New compact class vehicles. The development of this transmission has been aimed at improving fuel economy and achieving the weight reduction and compact size. In order to achieve these goals, the gear train and motor have been newly designed and advanced technology applied. This paper describes the major features and performance of this transmission in detail.

For DC brush motors directly driven by 42V vehicle battery, carbon brush deterioration due to high voltage arc is a major factor to determine motor life [1]. The brush deterioration is significant especially in multipolar motors with lap-wound armature because they allow a large circulating current to flow into their brushes and it decreases commutation performance [2], [3], [4]. In this report, we propose 1) a new brush material capable of preventing brush deterioration even under high-voltage conditions and 2) a new winding method to minimize circulating current under electromagnetic polarization and to suppress high-voltage arc. With each of these new technologies, DC brush motor driven by 42V battery can operate longer than that driven by 14V battery.

Automotive and truck manufacturers are introducing electric propulsion systems into their ground vehicles to reduce fossil fuel consumption and harmful tailpipe emissions. The mobility shift to electric motors requires a compact thermal management system that can accommodate heat dissipation demands with minimum energy consumption in a confined space. An innovative cooling system design, emphasizing passive cooling methods coupled with a small liquid system, using a thermal bus architecture has been explored. The laboratory experiment features an emulated electric motor interfaced to a thermal cradle and multiple heat rejection pathways to evaluate the transfer of generated heat to the ambient surroundings. The thermal response of passive (e.g., carbon fiber, high thermal conductivity material, thermosyphon) and active cooling systems are investigated for two operating scenarios.

Improved propulsion system cooling remains an important challenge in the transportation industry as heat generating components, embedded in ground vehicles, trend toward higher heat fluxes and power requirements. The further minimization of the thermal management system power consumption necessitates the integration of parallel heat rejection strategies to maintain prescribed temperature limits. When properly designed, the cooling solution will offer lower noise, weight, and total volume while improving system durability, reliability, and power efficiency. This study investigates the integration of high thermal conductivity (HTC) materials, carbon fibers, and heat pipes with conventional liquid cooling to create a hybrid “thermal bus” to move the thermal energy from the heat source(s) to the ambient surroundings. The innovative design can transfer heat between the separated heat source(s) and heat sink(s) without sensitivity to gravity.

Enhanced electric motor performance in transportation vehicles can improve system reliability and durability over rigorous operating cycles. The design of innovative heat rejection strategies in electric motors can minimize cooling power consumption and associated noise generation while offering configuration flexibility. This study investigates an innovative electric motor cooling strategy through bench top thermal testing on an emulated electric motor. The system design includes passive (e.g., heat pipes) cooling as the primary heat rejection pathway with supplemental conventional cooling using a variable speed coolant pump and radiator fan(s). The integrated thermal structure, “cradle”, transfers heat from the motor shell towards an end plate for heat dissipation to the ambient surroundings or transmission to an external thermal bus to remote heat exchanger.

Designing an efficient cooling system with low power consumption is of high interest in the automotive engineering community. Heat generated due to the propulsion system and the on-board electronics in ground vehicles must be dissipated to avoid exceeding component temperature limits. In addition, proper thermal management will offer improved system durability and efficiency while providing a flexible, modular, and reduced weight structure. Traditional cooling systems are effective but they typically require high energy consumption which provides motivation for a paradigm shift. This study will examine the integration of passive heat rejection pathways in ground vehicle cooling systems using a “thermal bus”. Potential solutions include heat pipes and composite fibers with high thermal properties and light weight properties to move heat from the source to ambient surroundings.