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Robustness is particularly important in complex systems of systems due to emergent behaviour. This paper presents two novel, techniques developed as part of a framework for design for robustness of complex automotive electronic systems, but in principle could be applied to a broad range of distributed electronic systems. The overall framework is described to give the context of use for the techniques. The first technique is a “robustness case” which is a structured argument for the robustness of a system analogous to a safety case. The second is a model based approach to early robustness verification of complex systems. The approaches are demonstrated by their application to the system initialisation of the propulsion control system of a hybrid electric vehicle. The hybrid system initialisation process is discussed in terms of the key objectives and the technical implementation, illustrating the level of complexity underlying a simple high level requirement.

An automotive side door latch release mechanism has been modelled for the locking and unlocking vehicle functionality in Dymola. The performance of the developed door lock model is evaluated against an existing model of a similar door locking/unlocking system in Stateflow. The model performance is also compared with measurements from a real vehicle door latch. The model is converted into a Simulink model and built for a real-time environment such as the dSPACE target with a fixed step size solver. It is shown that a step size as small as 1 ms can be used for real-time simulation without task overrunning in the real-time target. The model is also benchmarked on a multiprocessor setup as multiprocessor simulators are common in system-level networked Electronic Controller Unit (ECU) testing facilities for implementing high fidelity closed loop models of integrated ECUs and actuators.

The increasing use of distributed functions in vehicles can introduce unexpected and undesirable emergent behavior. This can be as a result of transient events such as sudden drops in the supply voltage. In this situation system behavior is often not adequately specified or controlled. This paper presents a novel approach to automotive electronic systems testing addressing robustness against low voltage transient conditions. The paper will discuss the technical output as well as performance in real-world test usage. The proposed approach uses a combination of pseudo-random number generator algorithms to generate parameterized supply voltage waveforms simulating low voltage transient conditions, used to drive the system-under-test (SUT).

The objective of the research discussed in this paper is to propose a methodology for comparing candidate electrical architectures on a cost basis at the very beginning of the architecture design process. To achieve this objective, historical data concerning the cost of a wiring harness for a driver’s door electrical system is analysed along with information on an electrical architecture for the door system of a small four door passenger car. The study is focused around a driver’s door electrical system based on LIN and hardwired integration. However, it is concluded that the results are applicable to other types of automotive electrical architectures.

In a current premium vehicle the infotainment system is typically implemented as a distributed system consisting of a number of modules communicating via a Media Oriented Systems Transport (MOST) network. Typical issues with such systems of systems (SoS) are emergent behaviour as systems interact in an unanticipated manner particularly during some initialisation conditions where it may be possible to get delays and failures in individual systems. Testing of infotainment systems at an overall level is conventionally carried out manually by an expert who can observe at a customer level but this has limitations affecting test coverage and effectiveness. Hence there is a requirement for an automated infotainment testing system which replicates a human expert encompassing relevant sensory modalities relating to control (i.e. touch) and observation (i.e. sight and sound) of the system under test.

For a typical communications C-language software stack, its size in terms of ROM and RAM will be dependent upon the network properties such as number of nodes, schedules, messages and signals. A lot of this information is part of a more detailed design and during architecture selection only signal and nodal information will be available. Messages and schedule information will be part of a much more detailed part of the design process. The objective of the study described in this paper is to ascertain whether ROM and RAM requirements can be estimated from only node and signal information only as this is the information that tends to be available at the very beginning of the electrical architecture design process. Historical data from a LIN design and its associated communications stack is statistically analysed and used to develop a methodology for ROM and RAM requirement estimation.

There are a number of software-controlled features in today's automotive vehicles to meet the increasing number of requirements for comfort, safety, infotainment and reduced emissions. To meet the growing demands from such features, the software content is not only increasing rapidly, but also becoming increasingly distributed within the Electronic Control Units (ECUs), leading to the possibility of unwanted interactions and consequent loss of reliability. Therefore, the automotive software-based features have to be designed and verified using sophisticated tools and techniques. Formal methods-based techniques and tools have been used on various industrial designs over the past 6 years by one of the authors in development and applied research projects, collaborating with a number of automotive companies. The challenges faced in large projects are discussed in this context.

This paper describes work aimed at establishing in-tire sensor system technologies for tire/road contact patch force monitoring. The paper discusses alternative sensor technologies for tire/road contact patch measurement. These technologies include surface acoustic wave (SAW) electroactive materials and magnetoactive soft magnetic materials. The paper also describes the use of finite element based structural analysis techniques to simulate the behavior of the rolling tire at the microscopic level. The finite element simulations are being developed to understand the influence of continuous tire deformation on sensed responses.

This paper presents work aimed at investigating the feasibility of improved vehicle dynamics control through tyre/road contact patch force monitoring. The paper describes an experimental investigation of the tyre/ground contact patch behavior of an automobile tyre. The investigation was carried out on a rolling tyre using test rigs instrumented with a tri-axial force transducer to provide longitudinal, lateral and vertical stress measurements at the tyre/ground contact patch. The paper also describes a custom-made simulation model which combines the information contained in the tyre/ground contact patch experiments with a standard vehicle dynamics and tyre characteristics model. Results arising from typical automobile maneuvers performed using this tyre-vehicle simulation model are presented and their significance is explained.

A driver model has been created in order to aid the development of new technologies that have the potential to enhance vehicle handling. This paper describes an investigation into the representation of different steering styles for human performance modeling. Different steering styles result in individual drivers using different steering inputs when negotiating an identical manoeuvre. The work is motivated by the effect of different steering styles on drivers' assessments of vehicles and the consequent possibility of engineering future vehicles to optimise the driver/vehicle combination. To achieve this optimisation, a driver model that is able to digitally represent different steering styles is required. Optimal control theory is used to formulate such a driver model; a cost functional represents the driver's motivation.