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The network is becoming the development focus for the in-vehicle electronic system. Network buses are used to improve communication between ECUs and to reduce the wiring costs. In-vehicle network buses, such as CAN, LIN, FlexRay, have become the central technique for sharing sensor data among vehicle ECUs. Gateways are a critical factor in vehicle network design with applications requiring the use of several networking standards. There are lots of networking protocols to choose from - each with advantages and disadvantages. No one protocol satisfies the requirements of all automotive applications. There is a need to consolidate data from these networks using de-centralized processing. As such, a gateway is used as a central hub to interconnect and process data from a vehicle's embedded networks. A gateway is composed of several automotive networking interfaces such as CAN, LIN and FlexRay in addition to embedded micro-controllers and peripheral functions.

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.

A large telescope aperture, stringent thermal stability and temperature range requirements, and a passively-cooled 150°K module presented major challenges in thermal design and hardware fabrication of this Small Explorer science instrument. This paper details SWAS thermal system design, problems that were revealed in thermal testing, and the hardware changes that brought the design into an acceptable condition. Thermal test techniques that helped verify design adequacy are described, as well as the analytical methods used to correlate the thermal model and predict flight performance.

This paper looks into the use of simulation software to develop and maintain diagnostic systems on Car networks. It is done through automatic code generation, while also taking advantage of the Real-time benefits of Simulation software. It will concentrate on the Key Word Protocol (KWP 2000) functioning along a CAN-BUS network as a means to illustrate the benefits of the design of such software. The paper will show the development of such software in its separate areas. Each area complies with the relevant ISO standards of Communication at the various ISO layers. It will also show how this is integrated with the external changeable data, using the SIMULINK Simulation software. This will be linked with Microsoft's Excel spreadsheet, allowing the separation of data from the application. Diagnostic code is then automatically generated. This code can be added automatically to an ECU to give it diagnostic functionality. This diagnostic design is easy to use and adaptable to existing models.

As automotive technology becomes more sophisticated the ability to troubleshoot and identify a malfunction becomes a more difficult and complex task, particularly without the assistance of specialised tools. A car manufacturer with the facility to identify and diagnose a malfunction before direct contact from the customer and possibly before the customer becomes aware that a problem exists would have a real competitive advantage in the market place. This paper proposes an architecture that may make this a reality. The architecture enables diagnostic information to be sent to a Case Based Reasoning (CBR) tool at the manufacturers premises when the car enters a hotspot (WI-FI enabled location). The CBR tool subsequently reviews diagnostic information to determine if a malfunction has occurred. If a malfunction is identified the customer is informed of the problem and is prompted to bring the car to a garage.

A modern automobile is becoming far more complex with the release of each new model. Complexity arises in the form of new mechanical devices, electronic devices and nowadays software components. With this increase in complexity, the job of diagnosing a fault is becoming increasingly difficult, as the service technician now requires detailed knowledge in a range of disciplines. This paper describes an Intelligent Diagnostic System (IDS) that was developed to intelligently diagnose faults in a multi-ECU (Electronic Control Unit) environment. Intelligence is achieved by diagnosing several faults while always attempting to isolate a “core” faulty component instead of simply returning a series of faults.

A Power Management System is currently being researched and developed at the Centre for Automotive Research based at Waterford Institute of Technology, Ireland, to monitor, control and reduce the electronic power consumption of the 12/14V and 36/42V systems in modern and future vehicles. Over the last 40 years the growth in electronic power consumption in vehicles has risen due to customers' demands for built-in safety features such as Air Bags, ABS and Traction Control, and also comfort and convenience features such as Air Conditioning, Heated Seats and Navigation Systems. Now the introduction of new electronic systems such as X-By-Wire, stricter regulations for fuel emissions, as well as an increased demand for fuel economy, are stretching the capabilities of the current electrical system. Automotive manufacturers are trying to solve this problem in several ways, such as the introduction of 36/42V systems, the introduction of new power sources and the use of MOSFETs.

The Centre for Automotive Research WIT is developing a methodology and tool for optimally distributing OSEK Tasks throughout In-Vehicle Networks. This distribution methodology automates the OSEK Task - ECU allocation process, generating optimal solutions for the network, maximizing the number of OSEK Tasks per ECU and therefore allowing for either more complex functionality for the same ECU network or a reduction in the number of ECUs on the network. Overall, this should reduce development time and help save vehicle weight and costs.

Focusing mirrors for X-ray astronomy are almost always located near the open aperture of the X-ray telescope. Such a mirror is typically a concentric nest of near-cylindrical paraboloids. Controlling the mirror temperature and reducing thermal radiation to space is essential to reducing optical distortion of the mirror assembly. This has been successfully done in the past by a partially open structure, termed a precollimator, between the mirror and space; or in the case of metal mirrors, by conduction from the support structure. As designs for future missions strive for more collecting area to “see” fainter objects, the individual mirrors become more numerous and thinner, presenting new challenges to thermal control. We report here studies by the Smithsonian Astrophysical Observatory on thermal control of a 1.6m-diameter X-ray mirror assembly for the Constellation-X mission. The mirrors are 0.3 mm thick, and the nest contains of order 100-200 mirrors.

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.

The large optical apertures required by many space-based telescopes make thermal control of these optics a significant challenge. One technique which has been used for x-ray telescopes involves placing insulating tubes forward of the entrance aperture. The reduction in both conduction and direct view produces a thermal gradient along the tubes, increasing the effective sink temperature for the optics and reducing the effective radiant source temperature and heat flow to space. In another configuration the “tubes” are formed by aperture slots in a stacked assembly of flat, low-conduction baffle plates. Because these apertures collimate both incident x-rays and thermal radiation, such an assembly has been termed a “thermal precollimator.” This paper describes precollimator design principles and design, analysis and testing of a precollimator for the Advanced X-ray Astrophysics Facility (AXAF).