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Technical Paper

16 Optimisation of a Stratified Charge Strategy for a Direct Injected Two-Stroke Engine

Direct fuel injection is becoming mandatory in two-stroke S.I. engines, since it prevents one of the major problems of these engines, that is fuel loss from the exhaust port. Another important problem is combustion irregularity at light loads, due to excessive presence of residual gas in the charge, and can be solved by charge stratification. High-pressure liquid fuel injection is able to control the mixing process inside the cylinder for getting either stratified charge at partial loads or quasi-stoichiometric conditions, as it is required at full load. This paper shows the development of this solution for a small engine for moped and light scooter, using numeric and experimental tools. In order to obtain the best charge characteristics at every load and engine speed, different combustion chambers have been conceived and studied, examining the effects of combustion chamber geometry, together with injector position and injection timing
Technical Paper

1D Simulation of Turbocharged Gasoline Direct Injection Engine for Transient Strategy Optimization

This paper presents 1D engine simulation used for engine control strategy optimization for a twin-scroll turbocharged gasoline direct injection 2.0 L engine with twin camphaser. The results show good agreement of the engine model behavior with testbed acquisitions for a large amount of steady state set points and under transient operating conditions. The presented method demonstrates that a 1D engine code represents a useful and efficient tool during all steps of the engine control development process from design to real-time for such an advanced engine technology.
Technical Paper

2-Stroke CAI Operation on a Poppet Valve DI Engine Fuelled with Gasoline and its Blends with Ethanol

Controlled Auto Ignition (CAI), also known as Homogeneous Charge Compression Ignition (HCCI), is one of the most promising combustion technologies to reduce the fuel consumption and NOx emissions. Currently, CAI combustion is constrained at part load operation conditions because of misfire at low load and knocking combustion at high load, and the lack of effective means to control the combustion process. Extending its operating range including high load boundary towards full load and low load boundary towards idle in order to allow the CAI engine to meet the demand of whole vehicle driving cycles, has become one of the key issues facing the industrialisation of CAI/HCCI technology. Furthermore, this combustion mode should be compatible with different fuels, and can switch back to conventional spark ignition operation when necessary. In this paper, the CAI operation is demonstrated on a 2-stroke gasoline direct injection (GDI) engine equipped with a poppet valve train.
Technical Paper

A 6-Speed Automatic Transmission Plant Dynamics Model for HIL Test Bench

During the production controller and software development process, one critical step is the controller and software verification. There are various ways to perform this verification. One of the commonly used methods is to utilize an HIL (hardware-in-the-loop) test bench to emulate powertrain hardware for development and validation of powertrain controllers and software. A key piece of an HIL bench is the plant dynamics model used to emulate the external environment of a modern controller, such as engine (ECM), transmission (TCM) or powertrain controller (PCM), so that the algorithms and their software implementation can be exercised to confirm the desired results. This paper presents a 6-speed automatic transmission plant dynamics model development for hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software. The modeling method, model validation, and application in an HIL test environment are described in details.
Technical Paper


The military aviation services pay a phenomenal price due to turbine engine stall. Several of the major factors which comprise a substantial portion of the total price are presented. Included are weapon system development time, operational limitations, field maintenance problems, overhaul costs and accident rates. Also presented, in a general fashion, are several technical approaches to the solution of turbine engine stall. Fundamental research and orderly development of basic engine components, power control systems, and airframe and installation factors are discussed. Emphasis is placed on the need for tighter control of production tolerances and the requirement for united efforts in the integration of components into a complete system.
Technical Paper

A Closed-Loop Drive-train Model for HIL Test Bench

This paper presents a hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software, with a focus on a closed-loop vehicle drive-train model incorporating a detailed automatic transmission plant dynamics model developed for certain applications. Specifically, this paper presents the closed-loop integration of a 6-speed automatic transmission model developed for our HIL transmission controller and algorithm test bench (Opal-RT TestDrive based). The model validation, integration and its application in an HIL test environment are described in details.
Technical Paper

A Design of Internet-Based Remote Manufacturing System

This paper discusses a design of Internet-based remote manufacturing system, which would help a global company to centralize its production, to control and to monitor the operation from the remote sites. In our design, we describe our system in two main categories, which are the design system and the manufacturing system. In the design system, we use the Internet-based client-server architecture to allow multiple clients to design products collaboratively and simultaneously. After the design is finished, it will be sent to the manufacturing system. At this stage, the clients can control and monitor the process from geographically distributed locations via the Internet.
Technical Paper

A Digital Memory Fuel Controller for Gasoline Engines

A digital memory fuel control unit has been developed for otto cycle engines which enables low pollution exhaust emissions to be achieved, coupled with good drivability and mechanical performance. The unit has been tested on a Triumph 2.5 PI vehicle, and the practical results achieved fall just short of the requirements of the 1975 federal and California legislation. The electronic controller receives signals relating to the engine's instantaneous operating conditions and, by reference to its digital memory, computes the optimum fuel required. The capacity of the controller's memory is effectively increased by an interpolation technique. The controller operates as an on-line process control computer, of cigar box dimensions, which is able to exist in the arduous automotive environment.
Technical Paper

A FEM Model to Predict Pressure Loading Cycle for Hydroforming Processes

Tubular hydroforming is a novel process that has recently gained much attention due to its cost-effective application in the automotive industry. Hydroformed automotive parts have high strength to weight ratio and have good repeatability with high dimensional accuracy. At this time, there is little experience in modeling the hydroforming process to better understand its application and researchers have tried using stamping simulation software to analyze the process. Unlike conventional sheet stamping which is a displacement driven process, tubular hydroforming is a force driven process and its success is governed by the nature of internal pressurization. Hence, a new three-dimensional finite element model using a computationally efficient 6-noded shell element has been developed. A simple pressure prediction model has been developed and integrated into the formulation for effective control of the process.
Technical Paper

A Fully Automatic System for the Morphology Characterization of High Pressure Diesel Sprays

To reduce pollutant emission and increase performance of vehicles, the first step is before combustion, to understand and then to control the mixing process of fuel with air. It is well known that injection inside the combustion chamber is the key phenomenon. This paper focuses on the spray morphology in engine like conditions. A complete system has been built based on an optical diagnostic to visualize the sprays under nitrogen back pressure chamber. To measure spray parameters from the recorded images an entropic thresholding has been implemented. An automatic algorithm computes the spray tip penetration and cone angle from the rough images with a correction of the measurements depending on the hole injection angle.

A Graphical Model for Interactive Distributed Control

The demonstrated architectural model and associated graphical techniques defined herein were developed to provide a simple method of visualizing the general functional operation or behavior of a Distributed Embedded System with a strong emphasis on representing system time characteristics.
Technical Paper

A Hardware-in-the-loop Test Bench for Production Transmission Controls Software Quality Validation

Production software validation is critical during software development, allowing potential quality issues that could occur in the field to be minimized. By developing automated and repeatable software test methods, test cases can be created to validate targeted areas of the control software for confirmation of the expected results from software release to release. This is especially important when algorithm/software development timing is aggressive and the management of development activities in a global work environment requires high quality, and timely test results. This paper presents a hardware-in-the-loop (HIL) test bench for the validation of production transmission controls software. The powertrain model used within the HIL consists of an engine model and a detailed automatic transmission dynamics model. The model runs in an OPAL-RT TestDrive based HIL system.
Technical Paper

A Laboratory Evaluation of Tires for Directional Control

Control of conventional vehicles in steering is based on development of lateral forces by the tires when operating at slip angles. However, the relationship between lateral force and slip angle is not always an adequate measure of the effectiveness of a tire in the process of control. Effects of load transfer must also be considered. The paper outlines an approach for incorporating phenomenon of load transfer and certain aspects of the vehicle configuration into the scheme of evaluation. The technique is substantiated in comparative tests with vehicles on the road. Examples are given of its use in studying the effectiveness of light truck tires in directional control.
Technical Paper

A Mechanistic Study of Aluminum Vacuum Brazing

The vacuum brazing of aluminum is an established industrial process which relies on strict process and materials control for the successful joining of products such as heat exchangers. The operating procedures developed for vacuum brazing are largely empirical and the interaction between materials and processing on brazeability continue to be reviewed. Changes to the surface of the filler metal and vacuum composition during simulated brazing cycles have been systematically investigated using a combination of surface analytical techniques together with residual gas analysis of the vacuum furnace atmosphere. This approach has been found to be particularly informative in characterizing the surface chemical and topographical changes which occur to the aluminum sheet during the brazing process. From this work a mechanistic model for vacuum brazing of aluminium has been developed.
Technical Paper

A Mid-Range Fuel Injection Pump and Its Electronics

This paper will outline one new in-line injection pump that is being released to production and the electronic controls that go with this pump and the other pumps that are currently in production. The in-line pump has an internal timing device and is designed to be especially compatible with the timing requirements needed for emission control. With the electronic controls the fuel injection pumps will have many advantages. The electronics will make the pump smooth and easy to use. The flexibility of the electronics will make possible a much better timing strategy which will approach the ideal emissions fuel consumption compromise. The use of the PROM will impact the large inventory of pump specifications and reduce the turnaround time for service.
Technical Paper

A Model for the Estimation of Inducted Air Mass and the Residual Gas Fraction using Cylinder Pressure Measurements

The availability of cylinder pressure sensors for use in production engines opens new possibilities for engine control. The use of these sensors allows reliable cylinder-individual measurement and control of the combustion process. To gain improvements in fuel economy and power output through the use of this information, appropriate models have to be developed. This paper describes a model for the estimation of the air mass as well as the residual gas fraction within the cylinder of a spark ignition (SI) engine. It has been found that the model allows good estimates within the normal operating range of an SI engine running at stoichiometric conditions.
Journal Article

A Model-Free Stability Control Design Scheme with Active Steering Actuator Sets

This paper presents the application of a proposed fuzzy inference system as part of a stability control design scheme implemented with active steering actuator sets. The fuzzy inference system is used to detect the level of overseer/understeer at the high level and a speed-adaptive activation module determines whether an active front steering, active rear steering, or active 4 wheel steering is suited to improve vehicle handling stability. The resulting model-free system is capable of minimizing the amount of model calibration during the vehicle stability control development process as well as improving vehicle performance and stability over a wide range of vehicle and road conditions. A simulation study will be presented that evaluates the proposed scheme and compares the effectiveness of active front steer (AFS) and active rear steer (ARS) in enhancing the vehicle performance. Both time and frequency domain results are presented.
Technical Paper

A New Approach for a Diesel Particle Filter Material With Liquid Phase Sintered Silicon Carbide and an Innovative Segmented Geometry

In this paper, a new diesel particle filter material made from silicon carbide sintered in a liquid phase is presented. The sintering process allows for controlling of certain parameters that influence the extrusion process, the material properties and hence the filtering characteristics. Furthermore, using triangular channel geometry to build up a wall flow filter makes it possible to have a newly segmented geometry that leads to hexagonal shaped filter cartridges. A variety of on the market available wall flow filter materials are compared with data about material porosity, particle size distribution, strength, specific filtration surface as well other parameters influencing the filtration efficiency. The material characteristics gathered are analyzed and evaluated.
Journal Article

A New Approach to Input and Output Monitoring for Microcontrollers Supporting Functional Safety

It is very common that a microcontroller is used in a safety relevant system to acquire data from sensors, process the data and then control actuators. With the shrink of technology every few years it becomes ever more common to use digital serial interfaces and high speed PWM links for both inputs and outputs. The microcontroller vendors have responded to the need for functional safety in the CPU cores by lock-stepping them and adding ECC to buses and memories. They are also implementing highly flexible and complex timer peripherals to be able to automate much of the real-time processing of the digital signals. However these timers are becoming significantly large, and many have their own embedded sequence engines or microkernels, which although powerful, often lack the rigorous diagnostic mechanisms required to reach ASILD.
Technical Paper

A New Approach to Spot Weld Feedback Control

Improvements in resistance spot weld (RSW) quality in sheet metal are desired for manufacturing consistency and cost reduction in the automotive business. This paper reports on a new feedback control concept for RSW that employs a unique process stabization technique. The process is stabilized such that mechanical instabilities and contact resistance variations are minimized. After process stability has been achieved, the weld is driven to expulsion and terminated. Under specified process and control conditions, termination of the weld coincides with formation of a high quality spot weld.