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Ethanol fuel is a sustainable energy resource intended to provide a more environmentally and economically friendly alternative to fossil fuels. Ethanol fuel for automotive applications is becoming increasingly widespread and its market is continuing to grow. Measurement of ethanol was traditionally done with an impinger and a gas chromatograph (GC) system but this method is not a direct measurement, usually requires manual handling and takes a long time for post processing of data. The Innova photoacoustic analyzer can directly measure the ethanol emissions in vehicle exhaust without using the impinger/GC system. For the past eight years at Chrysler, the Innova has been used as a stand alone analyzer and the emission sample bags were physically transported to the chemistry lab for ethanol measurement. The data had to be manually entered and post processed for the final results.

In the automotive industry simulation represents an essential tool for the development process of the functions designed and integrated within the Engine Control Unit (ECU). This approach applies to each stage of the development cycle to establish the possible physics which are modeled accordingly. The particular stage which relates to the validation of the Engine Control Unit uses test benches called Hardware In the Loop (HIL) systems. They simulate both engine and vehicle by means of integrated models. The characteristics of these benches represent the constraints for the real-time computation of these models, in particular when the Engine Control Unit test requires a highly detailed physical model. This paper attempts to treat the introduction of plant models based on a more accurate physical representation of the internal combustion engines into a Hardware In the Loop target.

The way automobiles are developed today is quite different from how it was done in 1960. The most visible changes are the different role played by the Tier 1 supplier community, the use of Computer Aided Engineering tools, and the increased emphasis on continuous improvements in development cost, time to market, and product quality. In particular, CAE has played a pivotal role in this drive for “faster, cheaper, and better”. Today, all automotive OEMs and all Tier 1 suppliers are using CAE tools for virtual prototyping. Yet there remain serious issues regarding the combined use of physical and virtual prototypes. Virtual prototyping does not benefit a lot from physical prototyping activities in the same company and vice versa. The problem is best stated in the following quote: “Everybody believes the test results, except the test engineer; nobody believes the analysis results, except the analyst.”

Hyundai Motor Company has combined physical and virtual testing tools to validate a full vehicle virtual prototype. Today a large number of physical tests are still required because the cycle of “design-build-test-change” relies on complex models of components and systems that typically are not easily validated. In order to shorten the development cycles, engineers perform multi-body simulations to dynamically excite components and systems and thereby estimate their durability under dynamic loads. The approach described herein demonstrates the feasibility of correlating the output from the corresponding physical and virtual prototype. Both synthetic and road load events are employed to excite physical and virtual vehicles, reveal difference in response, and ultimately improve the predictive capability of the model.

This paper describes the development and implementation of a real-time plant floor scheduling information support system. Successful production scheduling and control depends largely on the availability of complete and accurate plant floor status information. In general, data must be integrated from many different and disjointed information sources. Data may come from programmable logic controllers (PLC), automatic guided vehicles (AGV), automatic storage and retrieval systems (ASRS), bar-code systems, etc. In some cases the data may be incomplete, unavailable or may lack accuracy. In order to get a clear integrated view of the entire operation, all data must be consolidated, gaps filled, and inaccuracies nullified through intelligent compensation. The system being considered is based on the principles of dynamic modeling of asynchronously acquired shop floor events. It is based on a modified Petri Net which allows for the accurate and precise representation of plant floor logic.

This paper presents a novel communication architecture denoted as time-triggered (TT) Ethernet that integrates real-time and non-real-time traffic into a single communication architecture. TT Ethernet supports applications of different levels of criticality, from simple data acquisition systems, to multimedia systems up to the most demanding fault-tolerant real-time control systems. The event triggered traffic in TT Ethernet is handled in conformance with the existing Ethernet standards of the IEEE. The architecture deploys a TT Ethernet switch, which distinguishes between event-triggered (ET) and time-triggered (TT) Ethernet traffic. Time-triggered traffic is transmitted with a predictable transmission delay, whereas event-triggered traffic is transmitted on a best-effort basis. The paper elaborates on the usage of TT Ethernet for in-vehicle communication in order to integrate different in-vehicle communication subsystems into a single communication architecture.

Boeing is participating in a research program to study the feasibility of building a High Speed Civil Transport (HSCT). A program assumption is that the aircraft will not have a droop nose capability, requiring that the forward facing windows be replaced by large format displays showing the outside scene. We refer to this display as the External Vision System (XVS). The issues being addressed in this paper involve the integration of primary flight symbology into the XVS display. We point out how this integrated display is unique, falling someplace between a standard head-down primary flight display and a head-up display. We describe potential advantages of an integrated display as well as point out a number of possible problem areas. High level goals driving the display design are presented. We finish by describing a number of research and development issues, that if resolved, would contribute to the design effort.

The NCSU body flow computer program was modified to include the axial velocity component of propeller wakes. The energetic wake is represented by a series of ring vortices spaced along the body axis whose strengths are related to the engine power output and whose diameters are always larger than the maximum local body dimension. Agreeing at least qualitatively with limited full-scale wind tunnel data, the results indicated that aircraft drag increases linearly with power level for a given configuration.

Suspension development is one of the key steps in a complete vehicle development program. Computer simulation and analysis tools such as Multi Body Dynamics (MBD) simulation are used to refine initial concept and suspension parameters. Later on when a physical prototype is available the suspension system can be experimentally optimized at vehicle level. In this paper a new methodology is proposed which integrates virtual and experimental tools so that design, development and validation of the suspension system is carried out in the early phase of the vehicle development cycle with actual suspension components and without the need of a vehicle prototype. With this new approach, the design of any critical suspension components such as dampers can be optimized at the vehicle level. The new approach consists of combining the actual physical components on loading rig in closed loop with vehicle dynamic model running in real time.

Future government emission regulations have lead to the development and implementation of advanced aftertreatment systems to meet stringent emission standards for both on-road and off-road vehicles. These aftertreatment systems require sophisticated control and diagnostic strategies to ensure proper system functionality while minimizing tailpipe NOx and PM emissions across all engine operating conditions. In this paper, an integrated algorithm design approach with controls and diagnostics for an aftertreatment system consisting of a fuel doser, fuel reformer, LNT, DPF, and SCR is discussed.

The International Space Station (ISS) program is implementing system architecture changes to integrate Regenerative Environmental Control and Life Support System (ECLSS) functions, including urine processing, water processing, and oxygen generation, into the U.S. Laboratory element earlier in the ISS assembly sequence. The Regenerative ECLSS functions, originally not planned for operation aboard ISS until the launch of the Node 3 element in mid-2008, are now planned for launch on the ULF-2 flight in 2007 in order to provide early system operation and checkout. After the initial phase of operation in the U.S. Laboratory element, the Regenerative ECLSS hardware is planned to be transferred to Node 3 for permanent use in support of expanded ISS crews. Operation while in the U.S. Laboratory element requires both hardware and software architecture modifications in order to provide specific hardware interfaces, meet resource requirements, and provide command and control capability.

Synthesizing different customer and functional requirements into an acceptable design configuration within a given space constraints is a challenging task for design engineers. The principles for designing efficiency, noise levels, maneuverability, safety, durability, etc. into the product are well understood. However, designing for reliability, maintainability and quality turns out to be a long-drawn laborious process due to unavailability of simplified design procedures. The author in this paper develops the understanding of reliability, maintainability and quality design principles and methods for products, with specific reference to vehicle designs.

Since deterministic optimum designs obtained without considering uncertainty lead to unreliable designs, it is vital to develop design methods that take account of the input uncertainty. When the input data contain sufficient information to characterize statistical distribution, the design optimization that incorporates the probability method is called a reliability-based design optimization (RBDO). It involves evaluation of probabilistic output performance measures. The enriched performance measure approach (PMA+) has been developed for efficient and robust design optimization process. This is integrated with the enhanced hybrid mean value (HMV+) method for effective evaluation of non-monotone and/or highly nonlinear probabilistic constraints. When sufficient information of input data cannot be obtained due to restrictions of budgets, facilities, human, time, etc., the input statistical distribution is not believable.

Statistical energy analysis (SEA) has recently emerged as an effective tool for design assessment in the automotive industry. Automotive OEM companies develop vehicle models to aid design of body and chassis systems. The tire and wheel suppliers develop and supply component models to OEM companies in the engineering stage. In the model development process, some information on the vehicle side or component side is necessary for model development and correlation. A suitable termination representation of the vehicle characteristics on the tire/wheel model is required. This termination should account for the dissipation of energy on vehicle body and chassis side, otherwise the component model will overestimate the vibration responses and energy levels. On the vehicle model side, a representative simplified tire/wheel model may be sufficient for full vehicle road noise simulation.

Restraint systems in automotives are inevitable for the safety of passengers. Seat belts are one such restraint system in automotives that prevent drivers and passengers from being injured during a crash by restraining them back. Seatbelt on automotives has interface with Body-in-white (henceforth called as BIW) and Trim parts in-order to serve its purpose at vehicle level. One such interface part of seat belt is the web guide, which assists and ensures the nylon web’s smooth motion at different seat track positions. Web-guides on automotives ensure the flawless motion of seat belt web at pillar trim areas. In this paper, we are discussing alternate ways of assisting the seat belt web without the web-guide as a separate part. In-order to assist and ensure the motion of nylon web in its trajectory, we have extended the flange of the pillar trim involved.

In this paper we present an integrated approach which combines analysis of the effect of simultaneous variations in model input parameters on component or system temperatures. The sensitivity analysis can be conducted by varying model input parameters using specific values that may be of interest to the user. The alternative approach is to use a structured set of parameters generated in the form of a DFSS DOE matrix. The matrix represents a combination of simulation conditions which combine the control factors (CF) and noise factors. CF’s are the design parameters that the engineer can modify to achieve a robust design. Noise factors include parameters that are outside the control of the design engineer. In automotive thermal management, noise factors include changes in ambient temperature, exhaust gas temperatures or aging of exhaust system or heat shields for example.

The Closed Ecology Experiment Facilities (CEEF) can be used as a test bed for Controlled Ecological Life Support Systems (CELSS), because technologies developed for the CEEF system facilitate self-sufficient material circulation. Two experiments were conducted from September 27, 1999 to February 17, 2000 and from September 28, 2000 to February 9, 2001 in this study. In both experiments, rice and soybeans were cultivated sequentially in each chamber, having a cultivation bed area of 30 m2 and floor area of 43 m2, inside the Plantation Module (PM) with artificial lighting of the CEEF. 6 to 8 other vegetables were also cultivated in a chamber, having a cultivation bed area of 60 m2 and floor area of 65 m2, inside the PM with natural lighting in the first experiment and the second experiment. In both experiments, stable transplant and harvest of each crop were maintained during approximately one month, after approximately 3-months preparatory cultivation.

Computer simulation has been used as a vital and powerful tool for evaluating stresses in microelectronics packages due to thermal-mechanical loading. Experimental measurement and reliability testing have been performed for modeling correlation and verification. In the past several years, the authors have been integrating computer simulation and testing to significantly improve package reliability at Motorola SPS. Several examples are presented for illustration and demonstration of the methodology.

The torque transmission capability of a vehicle clutch is significantly influenced by the cover assembly's clamping load and the friction characteristic of the clutch disk's facing material. The clutch facing's frictional value can be drastically reduced as a result of excessively high temperatures (“fading”). Generous safety factors have been integrated into existing clutch systems to prevent any uncontrolled clutch slip. The diaphragm springs in the cover assembly have to be designed to provide high clamping loads. High clamping loads, however, also have disadvantages: the clutch components are heavy and expensive and the elements in the actuating and releaser systems are subjected to severe loads. The slip control presented here should serve to lower clutch system clamping loads and at the same time ensure that the clutch is reliably prevented from suffering any uncontrolled slip.

In several industrial fields, the integration of functions is a key technology to enhance the efficiency of components in terms of performance to mass/volume/cost ratio. Concerning the space industry, in the last few years the trend in spacecraft design has been towards smaller, light-weight and higher performance satellites with sophisticated payloads and instrumentation. Increasing power density figures are the common feature of such systems, constituting a challenging task for the Thermal Control System. The traditional mechanical and thermal design concepts are evidencing their limits with reference to such an emerging scenario.