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Abstract Identity-Anonymized CAN (IA-CAN) protocol is a secure CAN protocol, which provides the sender authentication by inserting a secret sequence of anonymous IDs (A-IDs) shared among the communication nodes. To prevent malicious attacks from the IA-CAN protocol, a secure and robust system error recovery mechanism is required. This article presents a central management method of IA-CAN, named the IA-CAN with a global A-ID, where a gateway plays a central role in the session initiation and system error recovery. Each ECU self-diagnoses the system errors, and (if an error happens) it automatically resynchronizes its A-ID generation by acquiring the recovery information from the gateway. We prototype both a hardware version of an IA-CAN controller and a system for the IA-CAN with a global A-ID using the controller to verify our concept.

In the new generation of engine control systems EDC/ME(D)17 Robert Bosch GmbH presents the approach for a common software architecture for gasoline and diesel systems. Motivations for this development are our customers' requirements for an open system architecture, the unification of engine type independent functionality and future business models for Hard- and Software. The architecture design supports a clear identification of common software components for a Gasoline and Diesel Control System by using the CARTRONIC domain model as a comprehensive basis for structures and interfaces of the application layer. To support software exchange with customers on any code level, a XML-based standard document type definition (DTD) is proposed. The requests for future business models is addressed by a layered architecture with consequent encapsulation of control unit hardware, sensors and actuators.

Three recent developments suggest cost-beneficial approaches to communications for Advanced Traveler Information Systems (ATIS) : 1) the use of FM subcarrier for efficient paging-type (digital) one-way broadcast, along with the upcoming introduction of Radio Data System (RDS) vehicle receivers, 2) the rapidly growing use of RF “tags” for automatic tolling, which have recently been upgraded for discrete zone two-way communication, and 3) the “signal processing gain” and “demand access” capability of spread-spectrum-type coding, which together make event-driven communications more feasible and cost-beneficial. An architecture concept exploiting these thrusts is outlined in terms of a “baseline” and a higher level ATIS. The baseline emphasizes basic traffic exception and safety messages and supports higher level (optional) services such as navigators and invehicle route guidance computers.

We describe the details of a particular compact and robust Corona Discharge Device (CDD™) that generates non-thermal plasma in the harsh environment of a stoichiometric exhaust. This particular CDD™ can generate plasma power of up to 15W at exhaust gas temperatures to 850C. Optimizations of geometry, material selection, and thermal design were performed by a combination of simulation and experiment. This particular design considered tradeoffs of several factors, including plasma power, EMI shielding, thermal durability, high voltage interconnection, packaging size, and exhaust emissions reduction. This particular CDD™ was designed to meet most of the same durability and survivability specifications as an O2 sensor, since both are exposed to similar exhaust environments.

This paper presents an analysis for evaluating electric machine and reducer specifications in conjunction with a comprehensive assessment of vehicle dynamics and drivability for an axial flux machine. The refence point for this study is a conventional central drive unit comprising a single electric machine, reducer, and differential. Powertrain architectures configured with two axial flux machines integrated as in-wheel drives as well as one axial flux machine mounted perpendicular to the chassis, are examined in comparison to the reference design. The study begins by establishing wheel-level traction force requirements and minimum power demands for a mid-sized vehicle. Subsequently, requisite machine and reducer specifications are derived based on these findings. Additional considerations encompass packaging constraints and efficiency thresholds.

As new technology is introduced into automotive engineering, the level of uncertainty regarding system robustness increases. With it reliability assessment tools that account for such uncertainty is expected to gain increased attention. This can naturally lead to Bayesian-based tools. This paper examines three reliability assessment methodologies that operate in the Bayesian framework. Two of them are geared towards electronic parts and assemblies, with the remaining one being geared towards systems in general. In doing so, they were critiqued in terms of four dimensions: (1) basic architecture, (2) input factors, (3) handling of qualitative data, and (4) failure rate updating mechanisms.

Electrification is the well-accepted solution to address carbon emissions and modernize vehicle controls. Batteries play a critical in the journey of electrification and modernization with battery voltage prediction as the foundation for safe and efficient operation. Due to its strong dependency on prior information, battery voltage was estimated with recurrent neural network methods in the recent literatures exploring a variety of deep learning techniques to estimate battery behaviors. In these studies, standard recurrent neural networks, gated recurrent units, and long-short term memory are popular neural network architectures under review. However, in most cases, each neural network architecture is individually assessed and therefore the knowledge about comparative study among three neural network architecture is limited. In addition, many literatures only studied either the dynamic voltage response or the voltage relaxation.

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.

As the automotive industry faces tighter fuel economy and emission regulations, it is becoming increasingly important to improve powertrain system efficiency. One of the areas to improve powertrain efficiency is the thermal management system. By controlling how to distribute the heat rejected by the engine, especially during the warm-up stage under cold temperatures, an engine thermal management system can improve the overall energy efficiency of the powertrain system. Conventionally, engine thermal management systems have been operated by a mechanical water pump and a thermostat. However, the recent introduction of electric water pumps and electrically-controlled flow valves allow for more sophisticated control of the thermal management system. In this study, these two different thermal management system architectures are investigated by conducting simulations.

Advanced combustion engines dominate all automotive applications. Future high efficiency clean combustion engines can contribute significantly to sustainable transportation. Effective ignition strategies are studied to enable lean and diluted combustion under considerably high-density mixture and strong turbulences, for improving the efficiency and emissions of future combustion engines. Continuous discharge and multi-site ignition strategies have been proved to be effective to stabilize the combustion process under lean and EGR diluted conditions. Continuous discharge strategy uses a traditional sparkplug with a single spark gap and multiple ignition coil packs. The ignition coil packs operate under a specific time offset to realize a continuous discharge process with a prolonged discharge duration. Multi-site ignition strategy also uses multiple ignition coil packs.

In an effort to help future crewed spacecraft thermal control analysts understand the characteristics of one-and two-loop Active Thermal Control Systems (ATCS), a comparison was made between the one- and two-loop ATCS architectures officially proposed for the Crew Exploration Vehicle (CEV) in Design Analysis Cycle 1 (DAC1) and DAC2, respectively. This report provides a description of each design, along with mass and power estimates derived from their respective Master Equipment List (MEL) and Power Equipment List (PEL). Since some of the components were sized independent of loop architecture (ex. coldplates and heat exchangers), the mass and power for these components were based on the MEL and PEL of the most mature design (i.e. two-loop architecture). The mass and power of the two architectures are then compared and the ability of each design to meet CEV requirements is discussed.

Vehicle operation during cold-start powertrain conditions can have a significant impact on drivability, fuel economy and tailpipe emissions in modern passenger vehicles. As efforts continue to maximize fuel economy in passenger vehicles, considerable engineering resources are being spent in order to reduce the consumption penalties incurred shortly after engine start and during powertrain warmup while maintaining suitably low levels of tailpipe emissions. Engine downsizing, advanced transmissions and hybrid-electric architecture can each have an appreciable effect on cold-start strategy and its impact on fuel economy. This work seeks to explore the cold-start strategy of several passenger vehicles with different powertrain architectures and to understand the resulting fuel economy impact relative to warm powertrain operation. To this end, four vehicles were chosen with different powertrain architectures.

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.

The objective of this paper is to suggest the advantages of using SAE J1699 tests and methods as a basis for characterization of physical layer devices. This paper will examine some of the commercially available physical layer IC's that could be used to drive Class B and C multiplex networks. Device characteristics such as propagation delays, current consumption, and common mode will be presented. These characteristics could be used to test device performance in Class B and Class C multiplex applications. Also presented will be an introduction to the new SAE J1699 Recommended Practice for multiplex device testing and how J1699 might be used for physical layer device testing.

The space exploration enterprise that will lead to human exploration on Mars requires pressure suit system capabilities and characteristics that change significantly over time and between different missions and mission phases. These capabilities must be provided within tight budget constraints and severely limited launch mass and volume, and at a pace that supports NASA's over-all exploration timeline. As a result, it has not been obvious whether the use of a single pressure suit system (like Apollo) or combinations of multiple pressure suit designs (like Shuttle) will offer the best balance among life cycle cost, risk, and performance. Because the answer to this question is pivotal for the effective development of pressure suit system technologies that will met NASA's needs, ILC and Hamilton Sundstrand engineers have collaborated in an independent study to identify and evaluate the alternatives.

The Orion Crew and Service Modules are often compared to the Apollo Command and Service Modules due to their similarity in basic mission objective: both were dedicated to getting a crew to lunar orbit and safely returning them to Earth. Both spacecraft rely on the environmental control, life support and active thermal control systems (ECLS/ATCS) for the basic functions of providing and maintaining a breathable atmosphere, supplying adequate amount of potable water and maintaining the crew and avionics equipment within certified thermal limits. This assessment will evaluate the driving requirements for both programs and highlight similarities and differences. Further, a short comparison of the two system architectures will be examined including a side by side assessment of some selected system's hardware mass.

Machine learning components are widely used in autonomous vehicles for implementing functionalities related to perception and planning. To verify if the vehicle-level functionalities are as specified, one of the widely used approaches is requirements-based testing. However, writing testable requirements for machine learning components can be challenging since the machine learning outcomes are seldom known in advance. Nevertheless, it is important to have a specification that details the expected behavior from machine learning components. In this paper, we discuss different approaches to write a specification for machine learning algorithms that are used in autonomous vehicles. These approaches include natural language requirements, user stories, use case specifications, behavioral diagrams, data as requirements, and formal specification methods. We also propose a tabular specification method for specifying requirements of machine learning algorithms.

Abstract Present-day vehicles come with a variety of new features like the pre-crash warning, the vehicle-to-vehicle communication, semi-autonomous driving systems, telematics, drive by wire. They demand very high bandwidth from in-vehicle networks. Various ECUs present inside the automotive transmits useful information via automotive multiplexing. Transmission of data in real-time achieves optimum functionality. The high bandwidth and high-speed requirement can be achieved either by using multiple buses or by implementing higher bandwidth. But, by doing so, the cost of the network as well as the complexity of the wiring increases. Another option is to implement higher layer protocol which can reduce the amount of data transferred by using data reduction (DR) techniques, thus reducing the bandwidth usage. The implementation cost is minimal as the changes are required in the software only and not in hardware.

A concept for a miniature, mechanically pumped two-phase cooling loop with high thermal performance was developed. In this feasibility study, a miniature, annular gear pump was inserted into the liquid line of a two-phase LHP-type loop architecture. In contrast to capillary-pumped systems, the functions of liquid pumping and evaporative heat transfer were separated and could be optimized independently. The cooling system was tested in terms of heat transport capability, performance and stability using water as the working fluid. The results show a high heat transfer coefficient of >11 W/(cm2K), a high heat transport capability of >70 W/cm2, and stable working behavior in all orientations. These results were obtained with a device using a simple loop architecture and an evaporator design that was not optimized for this kind of operation.

This SAE Information Report represents an information report on a conceptual ITS architecture and its accompanying protocols from the perspective of Advanced Traveller Information Systems providers and users. While a specific logical and physical architecture for ITS is still in the development stages, this conceptual architecture provides a robust general view of ITS functions and interfaces.