Search Results

This paper outlines Pi Technology's approach to testing high-reliability automotive software. Based on data collected during an engine controller development, it discusses the value of different types of testing at various stages of the design process and when errors are found. The team structure used for embedded systems is discussed to provide the context in which software development occurs.

AIRCRAFT engines have taught engineers many valuable lessons, some of which may well be applied to the design of ground vehicle engines. These lessons are discussed here in detail by Mr. Young, who considers both the general lessons to be learned, such as the stress laid by the aircraft engineer on the importance of attention to even the minutest detail; and the specific lessons, such as the importance of good volumetric efficiency and how it is obtained by attention to valve port size, valve lift, and manifolds. Mr. Young warns, however, that aircraft-engine practice should not be followed too closely, so that the result would be considerable structural flexibility that might be detrimental in certain ground vehicle engines.

Neurolab was the last and most complex Life Sciences Spacelab mission flown. Neurolab, the third dedicated Life Sciences mission, included both human and non-human experiments and a greater variety of biospecimens and hardware than flown on any previous mission carrying Life Sciences experiments. Good science was accomplished, however unplanned engineering and operational events did occur. This paper addresses some of those issues, the pitfalls encountered in developing payloads for microgravity missions, and the lessons learned. It addresses hardware, biospecimen, and operational elements. It also suggests means of circumventing such issues as we progress towards development of payloads for the International Space Station. Recommendations are also made for pre- and post-flight processing.

Solar energetic particle events (SPE) in 1989, in the midst of Solar Cycle 22, provided some of the highest fluxes of charged particles observed at the Earth since the beginning of the satellite era. Data from the 1989 events have added substantially to our knowledge of the characteristics of SPE including their peak intensity, spectral variation, impulsiveness, and contribution to total fluxes over time scales of days and months. Some of the 1989 events were primarily single large pulses while others consisted of a series of pulses lasting over two weeks. Observations and understanding of the solar source of SPE and the effects of interplanetary space in modulating the flux of particles seen near the earth have improved since the very large events of Solar Cycle 19 in the late 1950's to early 1960's and the large isolated events of August 1972.

This paper reviews teaching methods for axiomatic design and discusses approached to dealing with difficulties commonly encountered when teaching engineering students and practicing engineers. Axiomatic design makes it possible to teach engineering design as a science, in that there are fundamental, underlying principles, the axioms, upon which the discipline is based. Three elements of axiomatic design are identified: the axioms, the structures, and the processes. The axioms assure that designs are adjustable and controllable, avoiding unintended consequences, and will be robust. The application of the axioms requires structures, and the creation of the structures and the physical integration of the parts requires processes. Criteria for evaluating the structure and the processes are presented. The essential nature of software for the creation of large design decompositions is discussed.

Solar particle events (SPE) are typically dominated by high-energy, low-linear energy transfer (LET) protons. Biological damage to astronauts during an SPE is expected to include a large contribution from high LET target fragments produced in nuclear reactions in tissue. We study the effects of nuclear reactions on integral LET spectra, behind typical levels of spacecraft and body shielding, for the historically largest flares using the high-energy transport code, BRYNTRN in conjunction with several biological damage models. The cellular track model of Katz provides an accurate description of cellular damage from heavy ion exposure. The track model is applied with BRYNTRN to provide an LET decomposition of survival and transformation rates for solar proton events.

The grinding process has lagged behind other metal cutting processes because of lack of universal data that can be used to predict results, and because there are usually more than 30 interdependent, unevaluated variables connected with each grinding job. This repels people who insist on proved data before making a change. There is little hope of such data being available in the near future; however, a simple method of trial and error will achieve the maximum effect of abrasive machining on jobs already in production. This method works the machine and wheel to higher production until some physical limitation has been reached that, for the moment, cannot be overcome by present techniques.

A solution is proposed to the upcrossing problem for a stress of a special form encountered in probabilistic torsional vibration analysis of marine Diesel engine shafting systems. For the case that two engine criticals occur at the same engine speed, the stress is modeled as a cyclostationary random process with two frequencies. An equivalent stationary process is defined, requiring that its envelope process has the same upcrossing rate as the envelope of the original cyclostationary random process. It is assumed that both processes have the same probability of upcrossing a specific threshold in a given time interval. Numerical implementation shows the applicability and efficiency of the method.

Rose-Hulman Institute of Technology is one of 17 universities competing in EcoCAR: The NeXt Challenge, a three year international competition where teams are challenged to design, build, and test a hybrid vehicle architecture utilizing alternative fuels to reduce the energy consumption and emissions production of a 2009 production GM vehicle [ 1 ]. Teams are presently in year one of the competition where students choose an architecture, specify components, and design the vehicle. Design includes both the mechanical integration of the parts as well as design of the supervisory control system for the hybrid system. Year two of the competition is the build phase, and year three is the optimization and refinement phase. The design phase lasts approximately 9 months and most teams will completely replace the original powertrain with a hybrid powertrain.

Under a collaborative interagency agreement between the U.S. Environmental Protection Agency and the U.S. Department of Energy (DOE), the National Renewable Energy Laboratory (NREL) performed a series of in-depth analyses to characterize on-road driving behavior including distributions of vehicle speed, idle time, accelerations and decelerations, and other driving metrics of medium- and heavy-duty vocational vehicles operating within the United States. As part of this effort, NREL researchers segmented U.S. medium- and heavy-duty vocational vehicle driving characteristics into three distinct operating groups or clusters using real-world drive cycle data collected at 1 Hz and stored in NREL’s Fleet DNA database. The Fleet DNA database contains millions of miles of historical drive cycle data captured from medium- and heavy-duty vehicles operating across the United States. The data encompass existing DOE activities as well as contributions from valued industry stakeholder participants.

This work will present the development of a Modular High Voltage Standardization suitable for US ARMY Ground Vehicles. The standardization is in support of the Army’s Modernization Strategy focus on Next Generation Combat Vehicle (NGCV). GVSC with Department of Defense partners (OECIF, NAVY) is leading the development of this High-Voltage (HV) Specification for Energy Storage Modules (ESMs), i.e. Li-ion batteries. Based on the operational requirements for ARMY platforms to operate in austere environments with no fixed charging infrastructure, it is anticipated that Hybrid Electric Vehicles would be the initial users of an ESM. Greater penetration of safe, low cost ESM in support of electrification will result in improved platform survivability, maneuverability and capability.

Diesel Particulate Filters (DPF) made of cordierite are generally used for diesel engine aftertreatment systems in both on-road and commercial off-highway vehicles to meet today’s worldwide emission regulations. PM/PN and NOx emission regulations will become more stringent worldwide, as represented by CARB2027 and Euro7. Technologies that can meet these strict regulations are required. As a result, aftertreatment systems have become more complex with limited space. Recently, off-highway OEMs have been interested in downsizing the aftertreatment system using concepts such as DOConFilter in an effort to reduce the size of the exhaust system. DOConFilter can effectively replace DOC + CSF or DOC + bare DPF systems with a single zone coated particulate filter. DOConFilter systems have an increased amount of coating compared to CSF as higher-filtration filters will become the norm. An undesirable increase in pressure drop is expected by adopting this new technology.

This paper identifies and discuss how a set of logistics and Supply Chain business process have been allowing International Engines South America to achieve successful results in its export projects. Initially, a briefly literature review presents some common business practices applied on International Logistics operations and in the Automotive Industry. A discussion about Supply Chain and Global Sourcing strategies are presented as well. Second part of this paper shows how International Engines deployed customer requirements for two different projects - the export operation of a Diesel Engines for 4 different plants in US applying Postponement strategy and VMI replenishment model to deliver more than one hundred configurations line set sequenced and the export operation of Diesel Engines Cylinder Heads applying also VMI and returnable packaging in the line hauling from Brazil to US.

Advanced safety features and new services in connected cars depend on the security of the underlying vehicle functions. Due to the interconnection with the outside world and as a result of being an embedded system a modern vehicle is exposed to both, malicious activities as faced by traditional IT world systems as well as physical attacks. This introduces the need for utilizing hardware-assisted security measures to prevent both kinds of attacks. In this paper we present a survey of the different classes of hardware security devices and depict their different functional range and application. We demonstrate the feasibility of our approach by conducting a case study on an exemplary implementation of a function-on-demand use case. In particular, our example outlines how to apply the different hardware security approaches in practice to address real-world security topics. We conclude with an assessment of today’s hardware security devices.

The thermal operational safety (TOS) of a vehicle ensures that no component exceeds its critical temperature during vehicle operation. To enhance the current TOS validation process, a data-driven approach is proposed to predict maximum component temperatures of a new vehicle project by leveraging the historical thermal wind tunnel data from previous vehicle projects. The approach intends to support engineers with temperature predictions in the early phase and reduce the number of wind tunnel tests in the late phase of the TOS validation process. In the early phase, all measurements of the new vehicle project are predicted. In the late phase, a percentage of measurements with the test vehicle used for the model training and the remaining tests are predicted with the trained ML model. In a first step, data from all wind tunnel tests is extracted into a joint dataset together with metadata about the vehicle and the executed load case.

Model based computer-aided processes offer an economical and accelerated alternative to traditional build-and-test "Edisonian" approaches in engineering design. Typically, a CAE based design problem is formulated in two parts, viz. (1) the inverse design problem which involves identification of the appropriate geometry with desired properties, and (2) the forward problem which is the prediction of performance from the product geometry. Solution to the forward problem requires development of an accurate model correlated to physical data. This validated model could then be used for Virtual Verification of engineering systems efficiently and for solving the inverse problem. This paper demonstrates the rigorous process of model development, calibration, validation/verification, and use of the calibrated model in the design process with practical examples from automotive chassis and powertrain systems.

Many automotive ECU system issues do not manifest themselves until later in the vehicle product development cycle, despite the extensive testing and stringent validations that the ECU may have gone through. When such a system-level issue is identified, engineers will traditionally rely on the available information collected from logged DTCs and memory dumps to root-cause the issue. They will then develop a solution that will either eliminate the defects in ECU or develop a robust design to mitigate the impact. However, engineers are faced with technical difficulties which include: (a) physical addresses for many RAM variables critical to find the root-cause are subject to change with various releases of software, (b) some variables “come and go” so it is challenging to find out how and when the undesired events happen, and (c) many variables that are needed to identify the root-cause are missing.

Product configurators are employed to select and spread bills of material for production builds. Service parts and aftermarket parts typically do not participate in the product configuration process. It is assumed that service parts are identical to, or directly related to, the parts used in production. This is not always the case. Often service requires a bill of material that differs significantly from the production bill - most commonly when customers request add on features at the dealership. Requests for add on features may occur soon after the delivery of a newly built vehicle to a dealer or any point in the operational life of the vehicle. There is an opportunity to leverage production order coding and product configuration processes to support the product after production build. Products with significant complexity and variation may benefit from a ‘service configuration’ process in addition to the ‘production configuration’ process.