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As part of a system model, a PEM fuel cell stack model is presented for functional tests and pre-calibration of control units on hardware-in-the-loop (HiL) test benches. From the basic idea to couple a 1-D membrane model with a spatially distributed abstraction of the gas channel, a real-time capable 1-D+1-D PEM FC stack model is constructed. Fundament for the HiL usage is an explicit formulation of the commonly implicit model equations. With that, not only calculation time can be reduced, but also model accuracy is preserved. A validation using test bench data emphasizes the accuracy of the model. Finally, a runtime and eigenvalue analysis of the stack model proves the real-time capability.

The way to autonomous driving is closely connected to the capability of verifying and validating Advanced Driver Assistance Systems (ADAS), as it is one of the main challenges to achieve secure, reliable and thereby socially accepted self-driving cars. Hardware-in-the-Loop (HiL) based testing methods offer the great advantage of validating components and systems in an early stage of the development cycle, and they are established in automotive industry. When validating ADAS using HiL test benches, engineers face different barriers and conceptual difficulties: How to pipe simulated signals into multiple sensors including radar, ultrasonic, video, or lidar? How to combine classical physical simulations, e.g. vehicle dynamics, with sophisticated three-dimensional, GPU-based environmental simulations? In this article, we present current approaches of how to master these challenges and provide guidance by showing the advantages and drawbacks of each approach.

Nowadays automobiles are getting smart and there is a growing need for the physical behavior to become part of its software. This behavior can be described in a compact form by differential equations obtained from modeling and simulation tools. In the offline simulation domain the Functional Mockup Interface (FMI) [3], a popular standard today supported by many tools, allows to integrate a model with solver (Co-Simulation FMU) into another simulation environment. These models cannot be directly integrated into embedded automotive software due to special restrictions with respect to hard real-time constraints and MISRA compliance. Another architectural restriction is organizing software components according to the AUTOSAR standard which is typically not supported by the physical modeling tools. On the other hand AUTOSAR generating tools do not have the required advanced symbolic and numerical features to process differential equations.

Software developers in the automotive sector must achieve high quality objectives. Many design and implementation errors are avoided by synthesizing code from model-based software specifications using automatic code generators such as ETAS' ASCET. To verify non-functional properties of the implementation, model-based design processes should be complemented with static program analysis tools like AbsInt's StackAnalyzer and timing analyzer aiT. ASCET, StackAnalyzer and aiT can be integrated in a way that the analysis results for code generated by ASCET are conveniently accessible from within the ASCET development environment. This gives ASCET users a direct feedback on the effects of their design decisions on resource usage, allowing to select more efficient designs and implementation methods. In the paper, we present the tools, the experimental integration, preliminary results and plans for further tool integration.

Already today the car is a complex embedded system with a multitude of linked subsystems and components. In future these distributed systems have to be developed faster and with high quality via integrated, optimized design process. Scalable systems with an increased maintainability can be generated, if an agreement on a standardized technical architecture (hard- and software) is made at the beginning of the development. The challenges in the design of such distributed systems can be met through advanced automotive systems and software engineering in conjunction with suitable processes, methods and tools. Because the designers that must collaborate are distributed in different divisions or companies, it is essential that an overarching model based design methodology is used.

The adoption of model-based development in the automotive industry has been driven by the need to respond to the challenges of producing software for high-volume applications: increasingly complex feature sets; shorter deadlines and low residual failure rates to minimize recalls. Empirical evidence suggests that model-based development does not adversely affect safety - passenger fatalities due to software failure are significantly lower than for any other root cause of death [3]. Good in-field results however, are no reason to be complacent because we need to establish that a system is safe before it enters service. The imminent arrival of ISO26262 provides a good opportunity to consider how the requirements for software in safety-related systems can be addressed by a model-based development approach. This paper considers how such an approach can support the requirements of an ISO26262-based development process.

Today’s modern automobiles are aimed at giving the user an intuitive, secure, and reliable experience, serving his needs before and even after completion of his trip. The advances in automotive and consumer electronics are defining new boundaries for manufacturers to meet these demands. Digital vehicle entry systems are one of the key technology advances that enable vehicle to interact with external dynamic entities (e.g., smartphone loaded with applications). The system authenticates the user with not only an entry into his/her vehicle, but also offer a wide range of personalized comfort functions, thus enriching the user experience. These requirements lead to a dramatic increase in software complexity coupled with market competition to support the automotive industry standard AUTOSAR (AUTomotive Open System ARchitecture). To master these challenges, an early virtual validation of the digital vehicle entry functions is crucial for success now more than ever.

With the growing number of electronic systems, broadening function range and ever increasing interaction complexity in modern vehicles, the validation and calibration of new software functions becomes more and more challenging. The expenditures associated with this rising complexity are further increased due to growing number of vehicle variants that are adapted to regional markets. This conflicts with the ever present cost pressure in the overall automotive industry to reduce both production and development costs. Performing the most costly tasks of the development earlier in the process, using simulation on the PC, CAD or validation in virtual environment is a promising approach in order to face these challenges.

This paper presents ETAS GmbH research and product development activities related to test automation for embedded systems in the automotive industry. We propose a structured approach to flexible, systematic and efficient test automation. This research is based on several years of experience with test automation processes, products and solutions. Current research and development activities are closely linked to a pilot customer, implementing unified and automated test processes across several divisions. Central aspects of our research include a precise definition of various tasks and roles in an overall test process, the flexible connection of test case development tools, and test bench independence. Our research helps create test solutions which offer improved reusability of test cases and better manageability of test processes.

This article describes how future Single-Chip ECU's can be debugged and calibrated using the new emerging debug standard known as GEPDIS informally named NEXUS. The paper explains why conventional debug and calibration methods no longer work with future ECU architectures. Infineon Technologies and some other leading semiconductor vendors and tool companies have worked on the development of a ‘global embedded processor debug interface standard’ called GEPDIS (1). Throughout this paper will use the GEPDIS short cut. The GEPDIS standard defines and implements a global, open, micro-controller development interface standard for embedded controller applications. The GEPDIS interface can be used for run-time Control, Code Execution and Data Trace, Calibration and Co-processor communication (for use in Rapid Prototyping).

The use of design of experiment (DoE) and data-driven simulation has become state-of-the-art in engine development and base calibration to cope with the drastically increased complexity of today's engine ECUs (electronic control units). Based on the representation of the engine behavior with a virtual plant model, offline optimizers can be used to find the optimal calibration settings for the engine controller, e.g. with respect to fuel consumption and exhaust gas emissions. This increases the efficiency of the calibration process and reduces the need for expensive test stand runs. The present paper describes the application of Gaussian process regression, a statistical modeling approach with practical benefits in terms of achievable model accuracy and usability. The implementation of the algorithm in a commercial tool framework enables a broad use in series engine calibration.

Since the early seventies, the development of the automobile has been characterized by a steady increase in the deploymnet of onboard electronics systems and software. This trend continues unabated and is driven by rising end-user demands and increasingly stringent environmental requirements. Today, almost every function onboard the modern vehicle is electronically controlled or monitored. The software-based implementation of vehicle functions provides for unparalleled freedoms of concept and design. However, automobile development calls for the accommodation of contrasting prerequisites – such as higher demands on safety and reliability vs. lower cost ceilings, longer product life cycles vs. shorter development times – along with growing proliferation of model variants. Automotive Software Engineering has established its position at the center of these seemingly conflicting opposites.