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This paper describes the development and experimental validation of a Plug-in Hybrid Electric Vehicle (PHEV) dynamic simulator that enables development, testing, and calibration of a traction control strategy. EcoCAR 2 is a three-year competition between fifteen North American universities, sponsored by the Department of Energy and General Motors that challenges students to redesign a Chevrolet Malibu to have increased fuel economy and decreased emissions while maintaining safety, performance, and consumer acceptability. The dynamic model is developed specifically for the Ohio State University EcoCAR 2 Team vehicle with a series-parallel PHEV architecture. This architecture features, in the front of the vehicle, an ICE separated from an automated manual transmission with a clutch as well as an electric machine coupled via a belt directly to the input of the transmission. The rear powertrain features another electric machine coupled to a fixed ratio gearbox connected to the wheels.

In many manual transmissions, conditions for the onset of vibro-impacts from an unloaded gear pair are more likely than from an engaged set. Although some of the general characteristics of neutral gear rattle are known, no specific analytical models are available in the literature that can explain interactions between unloaded and loaded gear pairs in the drive rattle mode. For the sake of illustration, a particular problem for a light duty truck is studied in this paper and dynamic interactions are investigated. Some experimental measurements are first presented to define the unloaded gear rattle problem. Linear and non-linear mathematical models of the driveline are developed to understand, quantify and control the rattle problem. Trends predicted by simulations are compared with those observed in experiments. The effects of various gear run-ups and vibratory drag torques are investigated.

Current emission control systems utilize a catalytic converter employing a three-way catalyst (TWC), composed of a mixture of noble metals to minimize the three main pollutant classes of NOx, CO, and HC. The TWC is most efficient when the air-to-fuel ratio (A/F) is at stoichiometry (i.e. A/F ≈ 14.7). The stoichiometric set-point region is maintained by the use of oxygen sensors composed of the solid-electrolyte yttria stabilized zirconia (YSZ) in an electronic feedback loop. As combustion gets leaner a different exhaust sensor can be utilized to give a measure of the level of pollutants. A NOx sensor is an alternative for an oxygen sensor that can be used for feedback control of engine combustion or exhaust NOx traps. A solid electrolyte disk composed of YSZ having two Pt electrodes with one being covered by a microporous zeolite material was tested as a sensor for combustion produced gases such as NO and NO2 in the presence of O2.

A newly developed process allows the near-net shape fabrication of alumina/aluminum composite bodies via the immersion of a sacrificial oxide preform into a molten aluminum alloy bath. The resulting composite possesses an attractive range of properties for application in several automotive components. These properties include: high strength and stiffness, appreciable thermal and electrical conductivity, high strength at elevated temperatures, coefficient of thermal expansion of 10 X 10-6 C-1 and relative ease of machinability. Low cost fabrication renders this material/process ideal for components such as brake rotors and calipers, cylinder bore liners, piston components.

A distributed parameter mathematical model of a complete power steering hydraulic transmission circuit has been developed and implemented on a personal computer to analyze the effect of tuning cables on the attenuation of pressure waves generated by the pump. Tuning cables, flexible tubes positioned coaxially inside a length of hose placed at a convenient location in the circuit, reduce fluidborne noise primarily by destructive interference and viscous damping. The model uses a transfer matrix approach that includes two-dimensional viscous flow and three-dimensional fluid-structure interaction. It can be used for sizing and positioning tuning cable devices in power steering as well as other hydraulic systems prior to verification testing of the circuit.

The process of producing co-continuous ceramic composite material has been investigated in order to provide a greater understanding of the formation mechanism and hence evaluate the viability of commercial applications for these exciting new materials. The ease of manufacture for components combined with the low production cost hold great promise for the production of brake rotors, brake calipers, piston crowns, cylinder liners, gears and turbine compressors. Practical issues such as bonding to this material, together with the machinability have been addressed, our findings are presented in this paper.

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.

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.

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.

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.

In this paper an automotive speed controller is developed for use in a car following scenario on an automated highway system. The throttle actuator used with the manufacturer's standard cruise control unit is used for throttle angle positioning and a multi-level control algorithm is developed for overall speed control. In addition, models of the throttle actuator, vehicle engine, torque converter, transmission, and longitudinal dynamics are presented.

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.

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.

The facial laceration test has been proposed as an addition to the dummy injury criteria of Federal Motor Vehicle Safety Standard 208. To better understand laceration conditions as they actually occur, three road crashes of increasing severity, all involving facial laceration by the broken (cracked) windshield and one involving partial ejection, have been simulated physically and analytically. The physical simulations used vehicle test bucks, the Hybrid III head with the chamois facial coverings of the facial laceration test, and a piston - constrained Head Impactor. Computer simulations of the three crashes were also carried out using the CALSPAN 3D “CVS” and the 2D “DRISIM” computer programs. The computer simulations provide insight into the effective mass of the head and body on windshield contact, and the forces, velocities, and accelerations involved.

Past studies have found that a pressure based injury risk function was the best predictor of liver injuries due to blunt impacts. In an effort to expand upon these findings, this study investigated the biomechanical responses of the abdomen of post mortem human surrogates (PMHS) to high-speed seatbelt loading and developed external response targets in conjunction with proposing an abdominal injury criterion. A total of seven unembalmed PMHS, with an average mass and stature of 71 kg and 174 cm respectively were subjected to belt loading using a seatbelt pull mechanism, with the PMHS seated upright in a free-back configuration. A pneumatic piston pulled a seatbelt into the abdomen at the level of the umbilicus with a nominal peak penetration speed of 4.0 m/s. Pressure transducers were placed in the re-pressurized abdominal vasculature, including the inferior vena cava (IVC) and abdominal aorta, to measure internal pressure variation during the event.

The development of an integrated Perforated Manifold, Muffler, and Catalyst (PMMC) for an automotive engine exhaust system is described. The design aims to reduce tailpipe emissions and improve engine power while maintaining low sound output levels from the exhaust. The initial design, based on simplified acoustic and fluid dynamic considerations, is further refined through the use of a computational approach and bench tests. A final prototype is fabricated and evaluated using fired engine dynamometer experiments. The results confirm earlier analytical estimates for improved engine power and reductions of emissions and noise levels.