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Electronic control units (ECUs) offer a modular, networked approach to real time machine control and diagnostics. Software embedded in these controllers offer agile and customizable solutions because of the intimate relationship with the ECU hardware and its inputs/outputs. In an idealistic view, embedded software should support the machine's life - 30 years or longer. Developing and maintaining software for these systems requires a strategy. A framework demonstrating common building blocks and long-term centralized support for ECUs on a machine is presented. This strategy reduces the detailed knowledge of the specific machine controls needed by ECU developers and provides the components and infrastructure key to extending the life and functionality of the ECU.

This paper introduces research work on 1-D model of Roots type supercharger with helical gears using 1-D simulation tool. Today, passenger car engine design follows approach of downsizing and the reduction of number of engine cylinders. Superchargers alone or their combination with turbochargers can fulfill low-end demands on engine torque for such engines. Moreover, low temperature combustion of lean mixture at low engine loads becomes popular (HCCI, PCCI) requiring high boost pressure of EGR/fresh air mixture at low exhaust gas temperature, which poses too high demands on turbocharger efficiency. The main objective of this paper is to describe Roots charger features and to amend Roots charger design.

It is well known that backpressure is one of the important parameters to be minimised during the exhaust system development. Unfortunately, during the first phases of an engineering process of a new engine, engine prototypes are not available yet. Due to this the exhaust system backpressure is generally evaluated using simulation software, and/or measuring the backpressure by a flow rig test at room temperature. Goal of this paper is to compare exhaust backpressure results obtained respectively: i) at the room temperature flow rig; ii) at the engine dyno bench; iii) by simulation with one of the most common 1D fluidodynamics simulation tool (Gt-Power). A correlation of the three different techniques is presented.

Transient engine operations are modeled and simulated with a 1-D code (GT Power) using heat release and emission data computed by a 3-D CFD code (Kiva3). During each iteration step of a transient engine simulation, the 1-D code utilizes the 3-D data to interpolate the values for heat release and emissions. The 3-D CFD computations were performed for the compression and combustion stroke of strategically chosen engine operating points considering engine speed, torque and excess air. The 3-D inlet conditions were obtained from the 1-D code, which utilized 3-D heat release data from the previous 1-D unsteady computations. In most cases, only two different sets of 3-D input data are needed to interpolate the transient phase between two engine operating points. This keeps the computation time at a reasonable level. The results are demonstrated on the load response of a generator which is driven by a medium-speed diesel engine.

This SAE Aerospace Standard (AS) contains requirements for a digital time division command/response multiplex data bus, for use in systems integration that is functionally similar to MIL-STD-1553B with Notice 2 but with a star topology and some deleted functionality. Even with the use of this document, differences may exist between multiplex data buses in different system applications due to particular application requirements and the options allowed in this document. The system designer must recognize this fact and design the multiplex bus controller (BC) hardware and software to accommodate such differences. These designer selected options must exist to allow the necessary flexibility in the design of specific multiplex systems in order to provide for the control mechanism, architectural redundancy, degradation concept, and traffic patterns peculiar to the specific application requirements.

This SAE Aerospace Standard (AS) contains requirements for a digital time division command/response multiplex data bus, for use in systems integration that is functionally similar to MIL-STD-1553B with Notice 2 but with a star topology and some deleted functionality. Even with the use of this document, differences may exist between multiplex data buses in different system applications due to particular application requirements and the options allowed in this document. The system designer must recognize this fact and design the multiplex bus controller (BC) hardware and software to accommodate such differences. These designer selected options must exist to allow the necessary flexibility in the design of specific multiplex systems in order to provide for the control mechanism, architectural redundancy, degradation concept, and traffic patterns peculiar to the specific application requirements.

Model-based software development is a well-established software development process and recognized by ISO26262 [1] as allowing for highly consistent and efficient development. Nevertheless, enhancing a model-based development process in such a way that it is compliant with the ISO26262 safety standard is a challenging task. To achieve ISO26262 compliance, the development team of a safety-related software project faces a multitude of additional requirements for the development process without a corresponding increase of the project budget to fulfill them. The fact that many of the requirements of ISO26262 are defined in a very generic way such that an interpretation is required further hampers their implementation. We propose a 10-step strategy to achieve an ISO26262 compliant model-based software development process. This strategy relates ISO26262 requirements with state-of-the art methods and approaches currently used for model-based software development.

Abstract The ASTM D130 was first issued in 1922 as a tentative standard for the detection of corrosive sulfur in gasoline. A clean copper strip was immersed in a sample of gasoline for three hours at 50°C with any corrosion or discoloration taken to indicate the presence of corrosive sulfur. Since that time, the method has undergone many revisions and has been applied to many petroleum products. Today, the ASTM D130 standard is the leading method used to determine the corrosiveness of various fuels, lubricants, and other hydrocarbon-based solutions to copper. The end-of-test strips are ranked using the ASTM Copper Strip Corrosion Standard Adjunct, a colored reproduction of copper strips characteristic of various degrees of sulfur-induced tarnish and corrosion, first introduced in 1954. This pragmatic approach to assessing potential corrosion concerns with copper hardware has served various industries well for a century.

The problem of testing large gas turbines at full load in the factory has been solved with the construction of a load test facility utilizing a gas turbine compressor as the load absorption device. Design philosophy and features are reviewed, and a summary, of operating experience to date is presented.

Nine identical 40-ft. transit buses were operated on B20 and diesel for a period of two years - five of the buses operated exclusively on B20 (20% biodiesel blend) and the other four on petroleum diesel. The buses were model year 2000 Orion V equipped with Cummins ISM engines, and all operated on the same bus route. Each bus accumulated about 100,000 miles over the course of the study. B20 buses were compared to the petroleum diesel buses in terms of fuel economy, vehicle maintenance cost, road calls, and emissions. There was no difference between the on-road average fuel economy of the two groups (4.41 mpg) based on the in-use data, however laboratory testing revealed a nearly 2% reduction in fuel economy for the B20 vehicles. Engine and fuel system related maintenance costs were nearly identical for the two groups until the final month of the study.

This standard covers un-shielded (JUTP) and shielded (STP) balanced single twisted pair jacketed data cable intended for use in surface vehicle cables for 1 Gb/s ethernet applications. The tests in this standard are intended to qualify cables for normal operation in an automotive environment while maintaining the necessary electrical properties for reliable data transmission.

This standard covers un-shielded (JUTP) and shielded (STP) balanced single twisted pair jacketed data cable intended for use in surface vehicle cables for 1000BASE-T1 ethernet PHY (1 Gb/s) applications. The tests in this standard are intended to qualify cables for normal operation in an automotive environment while maintaining the necessary electrical properties for reliable data transmission.

This SAE Standard covers un-shielded balanced single twisted pair data cable intended for use in surface vehicle cables for ≤100 Mb/s Ethernet applications. The tests in this document are intended to qualify cables for normal operation in an automotive environment while maintaining the necessary electrical properties for reliable data transmission.

Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.

System requirements and Interface Control Drawings (ICDs) make a variety of demands for MIL-STD-1553 remote terminals (RTs). Among these requirements are the need to ensure data integrity and sample data consistency, the need to perform bulk (multi-message) data transfers, and the need to offload the operation of the host CPU to the greatest degree possible. This latter requirement is reflected in such specifications as CPU spare bandwidth. The latest 1553 terminals provide a variety of choices for performing the different types of transfers. This paper provides a discussion of the hardware and software techniques for achieving these objectives. Three different schemes for RT subaddress memory management are presented: single message, circular buffer, and double buffered. For receive and transmit messages, these include fully synchronous single message transfers, asynchronous single message transfers, and multi-message transfers.