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Over the last few years the introduction of explicit system and software architecture models (e.g. AUTOSAR models) has led to changes in the automotive development process. The ability to simulate these models on a PC will be decisive for the acceptance of such approaches. This would support the early verification of distributed ECU and software systems and could therefore lead to cost savings. This paper describes an implementation of such an approach which fits into current development processes.

In modern vehicles the architecture of electronics is growing more and more complex because both the number of electronic functions – e.g. implemented as software modules – as well as the level of networking between electronic control units (ECUs) is steadily increasing. This complexity leads to greater propagation of failure symptoms, and diagnosing the causes of failure becomes a new challenge. Diagnostics aims at detecting failures such as defect sensors or faulty communication messages. It is subdivided into diagnosis algorithms on an ECU and algorithms running offboard, e.g. on a diagnostic tester. These algorithms have to complement each other in the best possible way. While in the past the diagnosis algorithm was developed late in the development process, nowadays there are efforts to start the development of such algorithms earlier – at least in parallel to developing a new feature itself. This would allow developers to verify the diagnosis algorithms in early design stages.

Increasing productivity along the development and verification process of safety-related projects is an important aspect in today’s technological developments, which need to be ever more efficient. The increase of productivity can be achieved by improving the usability of software tools and decreasing the effort of qualifying the software tool for a safety-related project. For safety-critical systems, the output of software tools has to be verified in order to ensure the tools’ suitability for safety-relevant applications. Verification is particularly important for test automation tools that are used to run hardware-in-the-loop (HIL) tests of safety-related software automatically 24/7. This qualification of software tools requires advanced knowledge and effort. This problem can be solved if a tool is suitable for developing safety-related software. This paper explains how this can be achieved for a COTS test automation tool.

Modern vehicles use Electronic Control Units (ECU), connected via Controller Area Network (CAN) to perform functions. Many of these functions are distributed across several ECUs. This network interconnection enables the sharing of sensors, calculated information and actuators. As new functionality is added, the number of ECUs and their complexity increase. This paper describes the values and possibilities of a Hardware-In-the-Loop (HIL) based Integration Lab, which enables a wide range of automatic tests to be performed on networked ECUs. The Integration Lab is the complex rebuild of a Scania truck/bus, containing the ECU superset, for connecting and testing networked ECUs. It involves more than 30 ECUs and eleven CAN networks.

Validating control units with hardware-in-the-loop (HIL) simulators is an established method for quality enhancements in automotive software. It is primarily used for testing applications, but in view of increased networking between electronic control units, it can also be used for testing communication scenarios. The testing of electronic control unit (ECU) communication often includes only positive testing. Simple communication nodes are used for this, and communication analyzers are used for verifying communication up to the physical level. However, it is not only an ECU's positive communication behavior that has to be tested, but also its correct behavior in the event of communication errors. In HIL communication scenarios, it is not only possible to emulate the missing bus nodes (restbus simulation) with a link to real-time signals; correct ECU behavior in the event of communication errors can also be tested.

In the aerospace industry, methods for virtual testing cover an increasing range of test executions carried out during the development and test process of avionics systems. Over the last years, most companies have focused on questions regarding the evaluation and implementation of methods for virtual testing. However, it has become more and more important to seamlessly integrate virtual testing into the overall development process. For instance, a company’s test strategy might stipulate a combination of different methods, such as SIL and HIL simulation, in order to benefit from the advantages of both in the same test process. In this case, efforts concentrate on the optimization of the overall process, from test specification to test execution, as well as the test result evaluation and its alignment with methods for virtual testing.

In recent years, the concept of hybrid test systems consisting of real and virtual parts emerged in the aerospace industry. The concept features a communication infrastructure that provides the standardized transport mechanisms required for interoperability. For example, this allows system integrators to easily reuse and exchange laboratory tests means, even if they originate from different suppliers. The “Virtual and Hybrid Testing Next Generation” (VHTNG) research project aims at creating a standard for such an infrastructure. One central aspect is the unified monitoring and control of the test equipment. So far, VHTNG has primarily focused on monitoring and controlling related aspects of the test bench in a local environment. However, recent events have repeatedly shown that it becomes increasingly important to monitor and control test benches remotely.

Permanently increasing software complexity of today's electronic control units (ECUs) makes testing a central and significant task within embedded software development. While new software functions are still being developed or optimized, other functions already undergo certain tests, mostly on module level but also on system and integration level. Testing must be done as early as possible within the automotive development process. Typically ECU software developers test new function modules by stimulating the code with test data and capturing the modules' output behavior to compare it with reference data. This paper presents a new and systematic way of testing embedded software for automotive electronics, called MTest. MTest combines the classical module test with model-based development. The central element of MTest is the classification-tree method, which has originally been developed by the DaimlerChrysler research department.

Model-based development is the established way of developing embedded control algorithms, especially for safety-critical applications. The aim is to improve development efficiency and safety by developing the software at a high abstraction level (the model) and by generating the implementation (the C code) automatically from the model. Although model-based development focuses on the models themselves, downstream artifacts such as source code or executable object code have to be considered in the verification stage. Safety standards such as ISO 26262 require upper bounds to be determined for the required storage space or the execution time of real-time tasks, and the absence of run-time errors to be demonstrated. Static analysis tools are available which work at the code level and can prove the absence of such errors. However, the connection to the model level has to be explicitly established.

Advanced driver assistance systems (ADAS) are becoming increasingly important for today's commercial vehicles. It is therefore crucial that different ADAS functionalities interact seamlessly with existing electronic control unit (ECU) networks. For example, autonomous emergency braking (AEB) systems directly influence the brake ECU and engine control. It has already become impossible to reliably validate this growing interconnectedness of control interventions in vehicle behavior with prototype vehicles alone. The relevant tests must be brought into the lab at an earlier development stage to evaluate ECU interaction automatically. This paper presents an approach for using hardware-in-the-loop (HIL) simulation to validate ECU networks for extremely diverse ADAS scenarios, while taking into account real sensor data. In a laboratory environment, the sensor systems based on radars, cameras, and maps are stimulated realistically with a combination of simulation and animation.

Model-based development and autocoding have become common practice in the automotive industry over the past few years. The industry is using these methods to tackle a situation in which complexity is constantly growing and development times are constantly decreasing, while the safety requirements for the software stay the same or even increase. The debate is no longer whether these methods are useful, but rather on the conditions for achieving optimum results with them. From the experiences made during the last decade this paper shows some of the key factors helping to achieve success when introducing or extending the deployment of automatic code generation in a model-based design process.

This paper discusses the standards that can currently be applied to production code generators and examines five standards in detail: OSEK/VDX, MISRA C, ISO/IEC 15504 (SPiCE), which is compared to ‘CMM for Software’, and IEC 61508. The issues involved in meeting these standards or integrating them in production code generators are discussed. The suitability of automatic production code generation in safety-critical applications is described, taking the TargetLink production code generator from dSPACE as an example.

This paper describes challenges and possible solution of hybrid electrical vehicles test systems with a special focus on hardware-in-the-loop (HIL) test bench. The degree of novelty of this work can be seen in the fact that development and test of ECU for hybrid electrical powertrains can move more and more from mechanical test benches with real automotive components to HIL test systems. The challenging task in terms of electrical interface between an electric motor ECU and an HIL system and necessary real-time capable simulation models for electric machines have been investigated and partly solved. Even cell balancing strategies performed by battery management systems (BMU) can be developed and tested using HIL technology with battery simulation models and a precise cell voltage simulation on electrical level.

Not only is the number of electronic control units (ECUs) in modern vehicles constantly increasing, the software of the ECUs is also becoming more complex. Both make testing a central task within the development of automotive electronics. Testing ECUs in real vehicles is time-consuming and costly, and comes very late in the automotive development process. It is therefore increasingly being replaced by laboratory tests using hardware-in-the-loop (HIL) simulation. While new software functions are still being developed or optimized, other functions are already undergoing certain tests, mostly on module level but also on system and integration level. To achieve the highest quality, testing must be done as early as possible within the development process. This paper describes the various test phases during the development of automotive electronics (from single function testing to network testing of all the ECUs of a vehicle).

Hardware-in-the-loop (HIL) test benches are indispensable for the development of modern vehicle dynamics controllers (VDCs). They can be regarded as a standard methodology today, because of the extremely safety-critical nature of the multi-sensor and multi-actuator systems used in vehicle dynamics control. The required high quality standards can only be ensured by systematic testing within a virtual HIL environment before going into a real car. This paper aims to provide a condensed technical over-view of state-of-the-art HIL test systems for VDCs, which are currently widely used in passenger cars, in the form of ABS and TCS, as well as ESP, or integrated chassis control, which is just coming onto the market. First, a short introduction to the basic functionality of these types of ECUs is given, and the reasons why HIL testing is necessary and especially useful for VDCs are discussed.

The number of electrical and electronic components in modern vehicles is constantly growing. Increasingly, functionalities are being distributed across several electronic control units (ECUs). While suppliers themselves are responsible for ensuring that individual ECUs function properly, only the OEM can test distributed functions. Moreover, with the volume of testing steadily growing, automated sequences are absolutely essential. To test electronic networks in the vehicle, Ford Europe is using platform-based hardware-in-the-loop simulation with integrated failure insertion. The company is setting up a uniform, project-independent procedure, from standardized test definition to automated test sequences on a virtual vehicle, right through to structured evaluation.

Due to tougher legislation on exhaust emissions reduction and the consumer demand for more power and mobility and less fuel consumption, the functionality in today's engine management systems continues to grow. The electronic engine control units (ECUs) have to perform more control tasks using new sensors and actuators, along with the corresponding self-diagnostics (OBD, on-board diagnosis). All this leads to continuously increasing demands on automated hardware-in-the-loop (HIL) test systems. HIL technology has advanced in parallel to the ECUs, and is today an indispensable tool for developing automotive electronics. This paper therefore aims to provide a comprehensive and state-of-the-art survey of HIL test systems for engine controllers. First of all, a brief introduction to the ECU's functionality is given.

Hardware-in-the-loop (HIL) simulation is now a standard component in the vehicle development process as a method for testing electronic control unit (ECU) software. HIL simulation is used for all aspects of development, naturally including safety-relevant functions and systems. This applies to all test tasks (from function testing to release tests, testing a single ECU or an ECU network, and so on) and also to different vehicle domains: The drivetrain, vehicle dynamics, driver assistance systems, interior/comfort systems and infotainment are all tested by HIL simulation. At the same time, modern vehicles feature more and more safety-related systems such as Adaptive Cruise Control, Electronic Stability Program, Power Assisted Steering, and Integrated Chassis Management.

The essential task of a battery management system (BMS) is to consistently operate the high-voltage battery in an optimum range. Due to the safety-critical nature of its components, prior testing of a BMS is absolutely necessary. Hardware-in-the-loop (HIL) simulation is a cost-effective and efficient tool for this. Testing the BMS on a HIL test bench requires an electronics unit to simulate the cell voltages and a scalable real-time battery model. This paper describes a HIL system that enables comprehensive testing of BMS components. Hardware and software solutions are proposed for the high requirements of these tests. The individual components are combined to make a modular system, and safety-critical aspects are examined. The paper shows that the system as developed fulfills all the requirements derived from the different test scenarios for BMS systems.

Electric drives are growing in importance in automotive applications, especially in hybrid electric vehicles (HEV) and in the vehicle dynamics area (steering systems, etc.). The challenges of real-time hardware-in-the-loop (HIL) simulation and testing of electric drives are addressed in this paper. In general, three different interface levels between the electric drive and the hardware-inthe-loop system can be distinguished: the signal level (1), the electrical level (2) and the mechanical level (3). These interface levels, as well as modeling and I/O-related aspects of electric drives and power electronics devices, are discussed in detail in the paper. Finally, different solutions based on dSPACE simulator technology are presented, for both hybrid vehicle and steering applications.