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This paper proposes a solution to the challenge of developing vehicle software application functions which are decoupled from their intended target hardware platforms. Once developed, these software application functions can be utilised across any OEM vehicle platform and vehicle variants, saving the supplier time and money in terms of system development and giving a number of OEMs similar tried-and-tested system application software. The proposed solution is to use the Model Driven Architecture (MDA)1, a UML-based development approach that separates the specification of system functionality from the specification of the implementation of that functionality on a specific technology platform. MDA allows a vehicle function to be modelled in a semantically rich UML [1,2] model which is completely independent of any implementation detail.

ODX (Open Diagnostics data eXchange) is a standard diagnostic data format specified by the European ASAM group, to simplify the exchange of vehicle diagnostic data between manufacturers, suppliers and service dealerships. The ODX database contains diagnostic data for the whole vehicle together with details of all vehicle ECUs. This paper gives an overview of the main categories of data contained in the ODX diagnostic database. A Windows-based diagnostic application was developed to execute ISO 15765 diagnostic services on ECUs, using an ODX database to define the allowed services and parameters for each ECU. The paper describes the structure of the diagnostic application and the steps that were necessary to process the ODX and tailor it to a production ECU.

The development of vehicle control systems has evolved to become an exercise in the design and integration of complex, distributed hardware and software components. The various components are typically developed by geographically dispersed, multicultural teams from both OEMs and suppliers. This paper gives a brief overview of using the Unified Modelling Language (UML) as a means of capturing the requirements of real-time distributed systems in a graphical notation shared by all team members. UML is commonly used to model system concepts, albeit typically as system “sketches” without any formal definition of the model's semantics. This paper specifically addresses the additions to the latest version of UML that supports higher levels of abstraction, model-based development, executable models and the specification of non-functional requirements.

In the paper the we discuss how the thermal behavior of the Advanced X-ray Astrophysics Facility (AXAF) optical system has been modeled and tested, and how these efforts have influenced the design of the telescope, especially as it relates the imaging performance. This includes the passive/active system covering the space-facing aperture known as the thermal “precollimator”, the mechanical support system that allows the large optical elements to survive the rigors of test in one-G and launch yet minimally affecting on-orbit optical performance, and the active thermal control design of the telescope. Methodologies for the frequently difficult task of transferring results from thermal analysis software to mechanical finite-element analyzers to model thermal deformations are discussed. The complexity of these distortions of the surfaces of the mirror elements required the use of optical raytrace models to assess imaging performance of the telescope.