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Technical Paper

Engine Control Using Torque Estimation

2001-03-05
2001-01-0995
In recent years, the increasing interest and requirements for improved engine diagnostics and control has led to the implementation of several different sensing and signal processing technologies. In order to optimize the performance and emission of an engine, detailed and specified knowledge of the combustion process inside the engine cylinder is required. In that sense, the torque generated by each combustion event in an IC engine is one of the most important variables related to the combustion process and engine performance. This paper introduces torque estimation techniques in the real-time basis for engine control applications using the measurement of crankshaft speed variation. The torque estimation scheme presented in this paper consists of two entirely different approaches, “Stochastic Analysis” and “Frequency Analysis”.
Technical Paper

Model-Based Component Fault Detection and Isolation in the Air-Intake System of an SI Engine Using the Statistical Local Approach

2003-03-03
2003-01-1057
The stochastic Fault Detection and Isolation (FDI) algorithm, known as the statistical local approach, is applied in a model-based framework to the diagnosis of component faults in the air-intake system of an automotive engine. The FDI scheme is first presented as a general methodology that permits the detection of faults in complex nonlinear systems without the need for building inverse models or numerous observers. Although sensor and actuator faults can be detected by this FDI methodology, component faults are generally more difficult to diagnose. Hence, this paper focuses on the detection and isolation of component faults for which the local approach is especially suitable. The challenge is to provide robust on-board diagnostics regardless of the inherent nonlinearities in a system and the random noise present.
Technical Paper

IC Engine Air/Fuel Ratio Feedback Control During Cold Start

1996-02-01
961022
This paper presents a method for air/fuel ratio control using combustion pressure feedback during cold start to be used as an aid in laboratory experiments. The effects of varying air/fuel ratio during cold start are so profound that small differences in air/fuel ratio can create effects that will mask the effects of significant changes in other variables. The ability to control air/fuel ratio is an important aid in comprehensive emission studies during cold start. This work will facilitate future studies of cold start emissions.
Technical Paper

Intelligent Control of Hybrid Vehicles Using Neural Networks and Fuzzy Logic

1998-02-23
981061
This paper discusses the use of intelligent control techniques for the control of a parallel hybrid electric vehicle powertrain. Artificial neural networks and fuzzy logic are used to implement a load leveling strategy. The resulting vehicle control unit, a supervisory controller, coordinates the powertrain components. The presented controller has the ability to adapt to different drivers and driving cycles. This allows a control strategy which includes both fuel-economy and performance modes. The strategy was implemented on the Ohio State University FutureCar.
Technical Paper

The Effects of Various Engine Control System Malfunctions on Exhaust Emissions Levels During the EPA I/M 240 Cycle

1994-03-01
940448
Ensuring the reliable operation of the emissions control system is a critical factor in complying with increasingly stringent exhaust emissions standards. In spite of significant advances, the performance of available diagnostic and test equipment is still amenable to further improvement, especially as it pertains to the diagnosis of incipient and intermittent faults. This paper presents experimental results pertaining to the diagnosis of complete, partial and intermittent faults in various components of the engine emissions control system. The instrumentation used in the study permitted simultaneous and essentially continuous analysis of the exhaust gases and of engine variables. Tests were conducted using a section of the EPA urban driving cycle (I/M 240), simulated by means of a throttle/dynamometer controller.
Technical Paper

Improved Knock Detection by Advanced Signal Processing

1995-02-01
950845
Engine knock has been recognized as a major problem limiting the development of fuel efficient spark-ignition engines. Detection methods employed in current knock control systems for spark ignition engines use a measurement of engine block vibration tuned to one or more resonance frequencies to extract knock-related information from the engine structural vibration. A major problem in the detection of knock (especially at higher engine speed) in commercial engines is the isolation of the desired signal from the contributions of the components other than those associated with the phenomenon under investigation. This is generally referred to as background noise. It is known that the engine knock resonance frequencies vary due to changes in combustion chamber volume and temperature during the expansion phase. Therefore, we propose an improved knock detection method using joint time-frequency analysis of engine block vibration and pressure signals.
Technical Paper

Methods for Internal Combustion Engine Feedback Control During Cold-Start

1995-02-01
950842
Legislation pertaining to automobile emissions has caused an increased focus on the cold-start performance of internal combustion engines. Of particular concern is the period of time before all available sensors become active. Present engine control strategies must rely on methods other than feedback control while these sensors are not active. Without feedback control during this critical period, engine emissions performance is not optimized. These conditions cause difficulty in performing comprehensive cold-start experiments. For these reasons, we have developed several methods for feedback control during cold-start to aid in laboratory investigations of engine emissions phenomena.
Technical Paper

On-Line Estimation of Indicated Torque in IC Engines Using Nonlinear Observers

1995-02-01
950840
An approach to fault diagnosis for internal combustion engines is considered. It is based on the estimation of cylinder indicated torque by means of sliding mode observers. Instead of measuring indicated pressure in cylinders directly, crankshaft speed is measured as the input of observers, which estimate the indicated torque. Several engine models are considered with different levels of complexity. The indicated torque estimation using sliding mode observers is based on the equivalent control method. The estimation technique is validated experimently on a research engine.
Technical Paper

Integrated Powertrain Diagnostic System: Linking On- and Off-Board Diagnostic Strategies

1996-02-01
960621
A number of automotive diagnostic equipment and procedures have evolved over the last two decades, leading to two generations of on-board diagnostic requirements (OBDI and OBDII), increasing the number of components and systems to be monitored by the diagnostic tools. The goal of On-Board Diagnostic is to alert the driver to the presence of a malfunction of the emission control system, and to identify the location of the problem in order to assist mechanics in properly performing repairs. The aim of this paper is to suggest a methodology for the development of an Integrated Powertrain Diagnostic System (EPDS) that can combine the information supplied by conventional tailpipe inspection programs with onboard diagnostics to provide fast and reliable diagnosis of malfunctions.
Technical Paper

Misfire Detection in a High-Performance Engine by the Principal Component Analysis Approach

1996-02-01
960622
The aim of this paper is to present the application of some signal processing and statistical analysis methods to the problem of detecting and isolating misfire occurrences in a twelve-cylinder high-performance engine. The method employed in this work is based on a measurement of engine angular velocity, processed in the frequency domain to extract a number of spectral components that are shown to be strongly affected by misfire events. These spectral components are then subject to a procedure known as Principal Components Analysis, in which the principal features of the angular speed waveform are extracted to generate individual cylinder misfire signatures. A clustering method is then implemented to permit the isolation of the cylinder responsible for the misfire. The paper briefly reviews the signal analysis method and presents experimental results supporting the validity of the approach.
Technical Paper

Engine Knock Analysis and Detection Using Time-Frequency Analysis

1996-02-01
960618
We have performed an extensive study of cycle-to-cycle variation of engine knock and its occurrence in order to have a better understanding of engine knock. Experimental studies show the randomness of knock as well as its frequency varying nature. We propose using time-frequency based signal detection method to improve knock detection since this method can track frequency variations in the measured signals. The fundamental idea behind time-frequency analysis is to be able to understand and describe how the spectral content of a signal is changing in time. Classical signal analysis has traditionally dealt with time and frequency separately. Such individual descriptions are good in situation where spectral content of signals do not change with time; however, there are often signals that have time-varying spectral content such as engine knock. It is shown that one gains more information about knock signals using time-frequency analysis method.
Technical Paper

Numerical and Experimental Study of Friction on a Single Cylinder CFR Engine

1996-02-01
960357
Three engine friction models of increasing complexity were developed in order to determine which type of model most effectively captured transient engine operation. Empirical constants for these models were determined through an optimization procedure using experimental data. These constants were then used with a simple dynamic model to produce overall simulations of the engine reciprocating and rotating dynamics. All three friction models appeared to provide useful results, however the two simpler models were much easier to implement. The most complex model presented some implementation problems, but promises to provide a more detailed picture of engine friction. The models were tested on a single cylinder research engine.
Technical Paper

Design of The Ohio State University Electric Race Car

1996-12-01
962511
The aim of this paper is to document a three year process of product development of the Formula Lightningtm electric race car constructed at the Ohio State University. Today interest in electric vehicles (EV's) is growing, due to the technological advances in recent years, but also in part due to recent legislation which mandates the introduction of ‘zero emission vehicles’ in California before the end of the century. The definition of ‘zero emission vehicle’ is: a vehicle which does not emit any pollutants during operation. Technologically, the only near term vehicle which meets this definition is an EV. One of the most difficult problems of electric racing is that the usable energy in a given set of batteries is not as easily determined as the amount of fuel in a tank. Also, the motor controllers may limit power output as battery voltage drops, further decreasing the amount of usable energy in a battery set.
Technical Paper

Motorsports in the Engineering Curriculum at The Ohio State University

1996-12-01
962498
This paper describes the background and development of a program focused on motorsports engineering education currently in progress at the Ohio State University (OSU). An interdisciplinary curriculum, with the involvement of various engineering departments, is being proposed for development in an attempt to address some of the engineering education needs of the motorsports industry. The program described in this paper strives to provide engineering students with an interdisciplinary background race engineering, and also provides opportunities for motorsports oriented thesis projects. The paper briefly summarizes the key elements of the curriculum, and describes how the integration of course material from different disciplines with team work on student competition projects, possibly coupled with internships with racing teams, can provide an ideal setting for the education of a new generation of race engineers.
Technical Paper

IC Engine Fuel System Diagnostics Using Observer with Binary Sensor Measurement

1997-02-24
970031
In this paper, we propose an IC engine fuel system diagnostic algorithm based on a discrete-event nonlinear observer using the production oxygen sensor. A mean value engine model is used to describe the engine dynamics. A procedure for designing the discrete event based observer is presented and applied to estimate important engine variables using the measured binary oxygen sensor output. The estimated variables are then used to perform diagnostics of the fuel system of the IC engine. Experimental results on a multi-cylinder production engine are presented to demonstrate the effectiveness of the proposed method.
Technical Paper

Combustion Diagnostics in Methane-Fueled SI Engines Using the Spark Plug as an Ionization Probe

1997-02-24
970033
The process of incorporating the spark plug as a combustion probe, to perform misfire and knock detection, air to fuel ratio and spark timing control has been the subject of research for some time now. [3], [4]. The feasibility of the approach however depends on being able to correlate some characteristic of the ion current signal to the in cylinder combustion process. Shimaski et al. [3] and Miyata et al. [4] suggest such a relationship. The objective of this research has been to extract combustion information from the measured ion current flowing between spark plug electrodes by using various advanced signal processing methods, and to develop a methodology that will permit combustion diagnostics and possibly control based on these measurements. Tests were carried out on a single-cylinder, methane-fueled CFR engine.
Technical Paper

Engine and Load Torque Estimation with Application to Electronic Throttle Control

1998-02-23
980795
Electronic throttle control is increasingly being considered as a viable alternative to conventional air management systems in modern spark-ignition engines. In such a scheme, driver throttle commands are interpreted by the powertrain control module together with many other inputs; rather than directly commanding throttle position, the driver is now simply requesting torque - a request that needs to be appropriately interpreted by the control module. Engine management under these conditions will require optimal control of the engine torque required by the various vehicle subsystems, ranging from HVAC, to electrical and hydraulic accessories, to the vehicle itself. In this context, the real-time estimation of engine and load torque can play a very important role, especially if this estimation can be performed using the same signals already available to the powertrain control module.
Technical Paper

Performance of a Ceramic CO Sensor in the Automotive Exhaust System

1995-02-01
950478
A prototype CO sensor based on anatase TiO2 was fabricated and tested in a Ford V6 engine. Fuel combustion was programmed to be near stoichiometric conditions, and emissions were monitored with an FT-IR analytical instrument. The sensor, positioned near the oxygen sensor in the exhaust manifold, was successfully tested for 50 cycles of revving and idling, and was observed to respond quickly and reproducibly. The sensor response was correlated to the CO concentration at specific engine temperatures and was found to vary systematically with increasing concentrations. This sensor has promising potentials to monitor the efficiency of the catalytic converter.
Technical Paper

The Effect of Engine Misfire on Exhaust Emission Levels in Spark Ignition Engines

1995-02-01
950480
One of the gray areas in the implementation of regulations limiting the generation of pollutants from mobile sources is the actual effectiveness of the exhaust gas emissions control strategy in vehicles that have been in use for some time. While it is possible today to conduct limited diagnostics with the on-board engine computer by performing periodic checks to verify the validity of the signals measured by the on-board sensors, and to measure tailpipe emissions during routine inspection and maintenance, the task of correlating these measurements with each other to provide an on-line, accurate diagnosis of critical malfunctions has thus far proven to be a very challenging task, especially in the case of misfire.
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