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Induction machines (IM) are considered work horse for industrial applications due to their rugged, reliable and inexpensive nature; however, their low power density restricts their use in volume and weight limited environments such as an aerospace, traction and propulsion applications. Given recent advancements in additive manufacturing technologies, this paper presents opportunity to improve power density of induction machines by taking advantage of higher slot fill factor (SFF) (defined as ratio of bare copper area to slot area) is explored. Increase in SFF is achieved by deposition of copper in much more compact way than conventional manufacturing methods of winding in electrical machines. Thus a design tradeoff study for an induction motor with improved SFF is essential to identify and highlight the potentials of IM for high power density applications and is elaborated in this paper.

The purpose of this standard is to provide a method for packaging aircraft software parts for distribution using contemporary media or by electronic distribution. This project intends to standardize and provide guidance for the storage of floppy based software, currently packaged in media set parts. This standard format can be then stored or distributed on a single physical media member (CD-ROM), or by electronic crate. The obsolescence of floppy disks drive an urgent need for this guidance.

This standard defines a common configuration report format that can be retrieved from an aircraft for use by ground tools and maintenance personnel. Reports will be generated in Extensible Markup Language (XML) format and structured as defined by this document. Several optional elements and attributes are defined to allow flexibility for a given report. This standard provides aircraft manufacturers, regulatory agencies, and airlines a format standard for aircraft configuration reporting, and facilitates automated comparison of configuration data reports (e.g., authorized versus as flying, etc.).

This technical paper collection includes 8 papers from OEMs, suppliers, and academia detailing current brake engineering issues and technology. Topics covered include: NVH, controls, modeling, testing, brake drag, and hardware-in-the-loop evaluations.

This presentation proposes an approach to use ABS wheel speed sensor signals together with other vehicle state information from a brake control module to detect an unbalanced tire or tires in real-time. The proposed approach consists of two-stage algorithms that mix a qualitative method using band-pass filtering with a quantitative parameter identification using conditional least squares. This two-stage approach can improve the robustness of tire imbalance or imbalances. The proposed approach is verified through vehicle testing and the test results show the effectiveness of the approach. Presenter Jianbo Lu, Ford Motor Co.

An electrically-driven, intelligent brake unit has been developed, to be combined with a regenerative braking system in electric vehicles (EVs) and hybrid electric vehicles (HEVs) which went into production in 2010 - 11. The brake pedal force is assisted by an electrically driven motor, without using vacuum pressure, unlike conventional braking systems. The actuator can be implemented to coordinate with a regenerative braking system, and to have adjustable pedal feel through use of a unique pressure-generating mechanism and a pedal-force compensator. In this paper, we describe features of the actuator mechanism and performance test results Presenter Yukio Ohtani, Hitachi Automotive Systems

Virtual testing is a method that simulates lab testing using multi-body dynamic analysis software. The main advantages of this approach include that the design can be evaluated before a prototype is available and virtual testing results can be easily validated by subsequent physical testing. The disadvantage is that accurate specimen models are sometimes hard to obtain since nonlinear components such as tires, bushings, dampers, and engine mounts are hard to model. Therefore, virtual testing accuracy varies significantly. The typical virtual rigs include tire and spindle coupled test rigs for full vehicle tests and multi axis shaker tables for component tests. Hybrid simulation combines physical and virtual components, inputs and constraints to create a composite simulation system. Hybrid simulation enables the hard to model components to be tested in the lab.

Given the fast changing market demands, the growing complexity of features, the shorter time to market, and the design/development constraints, the need for efficient and effective verification and validation methods are becoming critical for vehicle manufacturers and suppliers. One such example is fault-tree analysis. While fault-tree analysis is an important hazard analysis/verification activity, the current process of translating design details (e.g., system level and software level) is manual. Current experience indicates that fault tree analysis involves both creative deductive thinking and more mechanical steps, which typically involve instantiating gates and events in fault trees following fixed patterns. Specifically for software fault tree analysis, a number of the development steps typically involve instantiating fixed patterns of gates and events based upon the structure of the code. In this work, we investigate a methodology to translate software programs to fault trees.

Real-time simulation of truck and trailer combinations can be applied to hardware-in-the-loop (HIL) systems for developing and testing electronic control units (ECUs). The large number of configuration variations in vehicle and axle types requires the simulation model to be adjustable in a wide range. This paper presents a modular multibody approach for the vehicle dynamics simulation of single track configurations and truck-and-trailer combinations. The equations of motion are expressed by a new formula which is a combination of Jourdain's principle and the articulated body algorithm. With the proposed algorithm, a robust model is achieved that is numerically stable even at handling limits. Moreover, the presented approach is suitable for modular modeling and has been successfully implemented as a basis for various system definitions. As a result, only one simulation model is needed for a large variety of track and trailer types.

Rapid control prototyping (RCP) is a widely used technique for verifying a controller's functional behavior. Typically, RCP uses a target processor with ample processing power and memory, which makes the technique attractive for engineers exploring new concepts. Presenter Thomas Erkkinen, MathWorks Inc.

Software content within commercial vehicles is growing exponentially. Emissions requirements, multiplexed communications, hybrid-electric technologies, active suspensions and smart sensors are amongst the technologies driving the increase in embedded code. Presenter Christoph Braeuchle , MKS Software, Inc.

The amount of software, computation and logic embedded into the vehicle systems is increasing. Testing of complex real time embedded systems using Hardware in Loop (HIL) simulations across different vehicle platforms has been a challenge. Data driven testing enables a qualitative approach to test these complex vehicle systems. It consists of a test framework wherein the test logic and data are independent of the HIL test environment. The data comprises variables used for both input values and output verification values. This data is maintained in a database or in the form of tables. Each row defines an independent test scenario. The entire test data is divided into three categories, High, Medium and Low. This feature gives the advantage of leveraging the same set of test data from Unit Level Testing phases to the Integration Test phase in the V-Cycle of software development. A data driven test approach helps the reuse of tests across vehicle platforms.

These advanced checks have resulted in development of many new diagnostic monitors, of varying types, and a whole new internal software infrastructure to handle tracking, reporting, and self-verification of OBD related items. Due to this amplified complexity and the consequences surrounding a shortfall in meeting regulatory requirements, efficient and thorough validation of the OBD system in the powertrain control software is critical. Hardware-in-the-Loop (HIL) simulation provides the environment in which the needed efficiency and thoroughness for validating the OBD system can be achieved. A HIL simulation environment consisting of engine, aftertreatment, and basic vehicle models can be employed, providing the ability for software developers, calibration engineers, OBD experts, and test engineers to examine and validate both facets of OBD software: diagnostic monitors and diagnostic infrastructure (i.e., fault memory management).

Edgewater Computer Systems Inc. product RTEdge Platform 1.2 is a software toolset supporting proof based engineering, implementation and deployment of software components, built using the RTEdge AADL Microkernel modeling subset. This is a small subset of the AADL component model and execution semantics, covering threads and thread-groups communicating solely through asynchronous event ports and through explicitly shared data ports. Threads behavior is expressed as state machines and dispatch run time semantics is encoded in a Run-time Executive, enforcing pre-emptive priority dispatch based on statically assigned event priorities, with ceiling priority protocol access to shared data. This simple AADL microkernel semantic core can support all dispatch policies, communication and synchronization mechanisms of a fully fledged AADL run time environment, permitting the systematic use of the RTEdge static analysis tools for AADL compliant software components.

The use of Engine Health Management (EHM) systems has been growing steadily in both the civilian and the military aerospace sectors. Barring a few notable exceptions (such as certain temperature and thrust margin monitoring) regulatory authorities around the world have not required these systems to be certified in any way. This is changing rapidly. New airframes and engines are increasingly being designed with the assumption that EHM will be an integral part of the way customers will operate these assets. This leads to a need for better guidelines on how such systems should be certified. The SAE E-32 committee on Propulsion System Health Monitoring is leading an industry-wide effort to develop a set of guidelines for certifying EHM systems.

This presentation shows the SCADE System product line for systems modeling and generation based on the SysML standard and the Eclipse Papyrus open source technology. SCADE System has been developed in the framework of Listerel, a joint laboratory of Esterel Technologies, provider of the SCADE�, and CEA LIST, project leader of the Eclipse component, Papyrus. From an architecture point of view, the Esterel SCADE tools are built on top of the SCADE platform which includes both SCADE Suite�, a model-based development environment dedicated to critical software, and SCADE System enabling model-based system engineering. SCADE System includes Papyrus, an open source component (under EPL license), integrated in the modeling platform of Eclipse. Using this integrated modeling platform, both system and software teams share the same environment for system development. Furthermore, other model-based tools can be added to the environment, due to the use of Eclipse.

Cyber security in the aviation industry, especially in relation to onboard aircraft systems, presents unique challenges in its implementation and management. The cyber threat model is constantly evolving and will continually present new and different challenges to the aircraft operator in responding to new cyber threats without either invoking a lengthy software update and re-certification process or limiting aircraft-to-ground communications to the threatened system or systems. This presentation discusses a number of system architectural options and developing technologies that could be considered to enhance the aircraft cyber protection and defensive capabilities of onboard systems as well as to minimize the effort associated with certification/re-certification. Some of these limit the aircraft?s vulnerabilities or in cyber terms, its ?threat surface?.