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Audio playbacks are mechanisms which read data from a storage medium and produce commands and signals which an audio system turns into music. Playbacks are constantly changed to meet market demands, requiring that the control software be updated quickly and efficiently. This paper reviews a 12 month project using the MATLAB/Simulink/Stateflow environment for model-based development, system simulation, autocode generation, and hardware-in-the-loop (HIL) verification for playbacks which read music CDs or MP3 disks. Our team began with a “clean slate” approach to playback architecture, and demonstrated working units running production-ready code. This modular, layered architecture enables rapid development and verification of new playback mechanisms, thereby reducing the time needed to evaluate playback mechanisms and integrate into a complete infotainment system.

Through the use of finite-element modeling, pressure patterns on the underside of seat foam can be computed for a variety of occupants and seating positions. A design tool has been created which allows an engineer to evaluate different layouts for a pressure-sensing bladder in just minutes. This is important to meet FMVSS-208 safety regulations for vehicles sold in the US. Further, an artificial intelligence search engine has been applied to this problem to achieve near-optimal performance given the constraints of the seat design. Results are shown and compared with the traditional manual method of layout design.

Model-based systems development relies upon the concept of an executable specification. A survey of published literature shows a wide range of definitions for executable specifications [1, 2, 3, 4, 5, 6, 7, 8, 9 and 10]. In this paper, we attempt to codify the essential starting elements for a complete executable specification-based design flow. A complete executable specification that includes a functional model as well as test cases, in addition to a traditional prose document, is needed to transfer requirements from a customer to a supplier, or from a systems engineer to electrical hardware and software engineers. In the complete form demonstrated here, sub-components of a functionally-decomposed system manifest as modular reuse blocks suitable for publication in functional libraries. The overarching definition provided by product architecture and by software architecture must also be harmoniously integrated with design and implementation.

Three vehicle rollovers have been reconstructed based on driver interviews and approximate measurements of crash artifacts. The purpose of this work is to provide insight into sensor signals prior to the onset of rollover. The three events include: a car-to-car T-bone leading to a roll of 90 degrees; an impact-induced skid leading to a roll with 6 quarter turns; and a single vehicle partly on-road event with three complete rolls. Sensor signals are derived using the PC-Crash tool, and characteristic features are identified. Insights derived from these events can aid in development of robust rollover detection algorithms and calibrations. Furthermore, by studying how pre-roll maneuvers may presage a rollover event, key requirements for system-of-systems safety architectures can be derived.

Increasing sophistication of electronic safety systems requires more advanced tools for design and optimization. Systems of safety products already being designed are becoming too interdependent to calibrate as stand-alone modules. Compounding this difficulty is the trend towards fewer test crashes and more sophisticated regulatory requirements. This paper presents a unified calibration approach to produce robust performance. First, the set of crash samples are extended using statistical techniques. Then an automated calibration tool using Genetic Algorithms is used to provide robust performance against deployment requirements. Finally, an expert systems is employed to ensure logical behavior. Together, these powerful methods yield calibrations which out-perform manual calibrations and can be completed in far less time.