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Technical Paper

Australian Initiatives in Traffic Management and Energy - Vehicle Parameters and Interactions

1988-03-01
871158
This paper reviews the interactions between vehicle and road designers, particularly in the area of fuel consumption related to traffic management. The need for increased interaction between vehicle and road designers is illustrated in the cases of truck traffic performance, truck technology, information technology in cars, car performance, speed control and road information. Fuel consumption models developed at the Australian Road Research Board are described for the purposes of traffic management analysis for intersections, road links and broad urban studies. These models are a major step towards appropriate choice of traffic control systems, but need accurate estimates of vehicle performance characteristics in real traffic.
Technical Paper

Experimental Determination of the Noise Emitting Parts of a Rotating Tire in the European Research Project TINO

1999-05-17
1999-01-1732
One of the objectives in the European Research project TINO is to identify, in detail, the surfaces of a rotating tire which actually generate the radiated noise. The approach is completely experimental and is based upon the ASQ (Airborne Sound Quantification) technique. The quantification of the contribution of the different tire surfaces to the sound pressure measured under defined conditions is carried out through a process of near-field measurements during rotation of the tire and static acoustic transfer function measurements. The ASQ method is further developed and tested when focussing at the applications. In first instance, the procedure has been validated and fine-tuned under well-controlled boundary conditions at a tire chassis dynamometer. The results of this first investigation served also as a “reference” set of data which has been used for verification and validation of numerical tire models.
Technical Paper

Tire/Pavement Interaction Noise Source Identification Using Multi-Planar Nearfield Acoustical Holography

1999-05-17
1999-01-1733
In this study, multi-planar Nearfield Acoustical Holography (NAH) is used to investigate noise radiated from the front, side and rear areas of single tires on a two-wheel trailer. Contributions to the radiated noise from the leading edge, trailing edge, and sidewall of the tire are identified. Two tires - an experimental monopitch tire and a production passenger car tire - are evaluated on a smooth asphalt pavement at 58 km/hr. From the measured complex pressure, acoustic intensity is reconstructed on three planes surrounding the tire using modified NAH procedures. Additionally, sound power levels are presented in tabulated and spectra forms. Tire noise generating mechanisms are inferred based on the results.
Technical Paper

Soft Control – Utilizing Existing I/O

1999-05-10
1999-01-1623
The Timken Company's Faircrest Steel Plant has numerous automated control systems. The Raw Material Handling System and a grinder application on the Billet Conditioning system needed upgrading; however, to control costs the upgrades had to use the existing I/O. The overall functionality of these two systems is vastly different. Soft control packages proved capable of interfacing with the existing I/O, satisfied the functional needs of the systems, and enhanced the overall functionality of the systems.
Technical Paper

Transmission Oil Degradation Warning Systems and Computing in Agricultural Tractors

2000-06-19
2000-01-1873
This communication examines three strategies of predictive lubricant monitoring and replacement, used for farm tractors or similar vehicles. These strategies optimise the draining periodicity. They are the off-line follow-up, the sensors follow-up and the analytical model follow-up. The implementation of the suggested analytical model will be discussed, on the basis of field collected data (on a series of tractors, either customer's or on loan). Regular oil samples, and significant ones carried out at the end of the study, were taken and analysed in order to predict the evolution of the lubricant characteristics. Extensions to the experimental study were carried out at the end of this work. They are discussed in the paper (FZG gear scuffing, 4 ball wear and EP…).
Technical Paper

Investigation of a Roll Control System for an Off-road Vehicle

2000-05-01
2000-01-1646
The current popularity of the Sport Utility Vehicle (SUV) market has led to new developments aiming to increase product performance. Such vehicles pose a significant challenge as they must perform to a high standard over a large variety of road conditions. Previously, emphasis has been placed on off-road ability. However, SUVs are now seen as an alternative to conventional luxury cars, and hence are expected to perform similarly, but without significantly degrading off-road performance. The introduction of a roll control system can achieve body roll levels lower than a conventional sports saloon, whilst improving off-road ability by removing the compromises associated with conventional anti-roll bars. This paper investigates the characteristics of such a system by developing a computer simulation of the vehicle and the associated roll control scheme.
Technical Paper

A Model-Based Failsafe System for the Continental TEVES Electronic-Stability-Program (ESP)

2000-05-15
2000-01-1635
The Electronic Stability Program (ESP) is a vehicle dynamics control system that supports the driver in critical driving situations. A basic component integrated in the ESP-system is an on-line sensor monitoring system which is mainly used for detecting faults in sensors as early as possible so that an erroneous control or system malfunction can be prevented. Aim of this contribution is to present a model based sensor monitoring system for ESP that was developed, implemented, and is produced in large volumes by Continental Teves.
Technical Paper

Bosch ESP Systems: 5 Years of Experience

2000-05-15
2000-01-1633
Although the total number of car occupants involved in accidents in Germany has not significantly reduced during the past 10 years, the number of fatalities has steadily decreased. Most of the severe accidents result from a loss of control of the car. The problem of the driver losing control of his car will be explained. This problem is then used to formulate the goal for the vehicle dynamics control system ESP (Electronic Stability Program, also known as VDC). The approach chosen to reach this goal will then be shown. It will be shown that the vehicle slip angle is a crucial indicator for the maneuverability of the automobile. Since the complete vehicle state is not readily available, estimation algorithms are used to supply the control algorithms with sufficient information. With the automatic control of the slip angle the required yaw moment can be generated by individual wheel slip control.
Technical Paper

Design of Front Wheel Active Steering for Improved Vehicle Handling and Stability

2000-05-15
2000-01-1619
Active steering has received lot of attention in the recent years because of the development of vehicle stability control systems and intelligent vehicle highway systems. Active steering systems allow for correction of the steer angle to achieve the desired vehicle yaw gain. The proposed system can be easily integrated with the vehicle stability control systems that use braking to control the vehicle yaw gain. The paper describes the concept of front wheel active steering system and the design techniques involved in order to achieve the desired performance from the system. The design techniques demonstrated in the paper do not address noise (gear rattles, motor noise, gear whine etc), electromagnetic compatibility and thermal issues related to DC motor and digital controller.
Technical Paper

New Electronically-Controlled Trolling System for Marine Gear

1999-09-28
1999-01-3262
A marine gear is a reversible reduction gear provided in an inboard engine typically used as a propulsion unit for fishing boats. One of its functions is to provide “trolling speed” to make the boat go very slow. Some devices to attain the trolling speed is already available, in which hydraulic oil pressure for clutch coupling is mechanically controlled to achieve the boat's slow speed. However, conventional device is not satisfactory in view of performance and operational handiness. The new control system reported here resolves such problem by utilizing a solenoid to achieve optimal control over the hydraulic oil pressure. It assures easy handling, and provides the most desirable performance for a fishing boat to go dead slow. The system has an additional function to deal with another concern about a marine gear, that is, the rattling noise of the driving gear which often occurs while the engine is running in the low speed range.
Technical Paper

A Study on the Effects of Recirculated Exhaust Gas Upon NOx and Soot Emissions in Diesel Engines with Scrubber EGR System

1999-09-28
1999-01-3266
The effects of recirculated exhaust gas on the characteristics of NOx and soot emissions under a wide range of engine loads are experimentally investigated using a four-stroke, four-cylinder, indirect injection, water-cooled marine diesel engine operating at two engine speeds. The aim of this study is to develop the EGR control system for reducing NOx and soot emissions simultaneously in diesel engines. The EGR system is used to reduce NOx emissions. And a novel diesel soot-removal device with a cylinder-type scrubber for the experiment system is specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. It is found that NOx emissions decrease markedly, especially at higher loads, while soot emissions increase owing to the drop of intake and exhaust oxygen concentrations, and the rise of equivalence ratio as the EGR rate is elevated.
Technical Paper

Verification of Heavy Truck EBS and ABS Using MatrixX Hardware in the Loop Tools

1999-11-15
1999-01-3713
The development of advanced ABS, EBS, and vehicle dynamics control systems requires significant resources and testing. Even in the most controlled environment, on-track vehicle tests are not repeatable. A heavy vehicle model combined with pneumatic brake hardware connected to actual brake system controllers creates a powerful engineering tool. This tool is useful for control system development, electro-mechanical actuator development, and brake system development. An existing heavy vehicle model is modified to interact with the realtime simulation hardware and the pneumatic brake system hardware. Data from several hardware in the loop simulations are presented.
Technical Paper

Improved Heavy Vehicle Wheel Dynamics Model Using MATLAB/SIMULINK

1999-11-15
1999-01-3707
The accuracy of existing rotational wheel dynamics models has been found to be insufficient for heavy vehicle Antilock Braking System (ABS) and Electropneumatic Braking System (EBS) simulation, specifically when wheelspeeds are at or near zero but the vehicle speed is not. Control strategies specific to ABS and EBS, the low frequency response of pneumatic actuation, and the practice of using fewer modulators than braked wheels require that a vehicle model be able to handle lockedwheel scenarios accurately. Commercially available models have been found unsatisfactory in this regard, and technical literature has not been found to address this issue.
Technical Paper

Emulating the Behavior of Truck Drivers in the Longitudinal Control of Headway

1999-11-15
1999-01-3706
This paper describes control system and psychological concepts enabling the development of a simulation model suitable for use in emulating driver performance in situations involving the longitudinal control of the distance and headway-time to a preceding vehicle. The developed model has mathematical expressions and relationships pertaining to the driver's skill in operating the brake and accelerator (“inverse dynamics”) and the driver's perceptual and decision-making capabilities (“desired dynamics”). Simulation results for driving situations involving braking and accelerating are presented to aid in understanding the research work.
Technical Paper

Investigation of Sulfur Sensitivity and Reversibility in Late-Model Vehicles

1999-10-25
1999-01-3676
The emissions impact associated with increasing gasoline sulfur content was investigated using eight late-model vehicles, most of which were equipped with advanced emission control systems and certified as California Low-Emission Vehicles. The effect of returning to operation on low-sulfur fuel on emissions was also investigated. Vehicle testing was performed using California Phase 2 Certification test fuels with nominal sulfur levels of 40 and 540 ppm in combination with the LA4 and US06 driving cycles. In addition to exhaust emission measurements, engine-out emissions, air-fuel ratio, catalyst composition, and catalyst temperature data were collected. The data showed that most of the vehicles were sensitive to gasoline sulfur content as emissions increased when the vehicles were operated on the higher-sulfur test fuel; however, the degree of sensitivity varied from vehicle to vehicle.
Technical Paper

Effects of Catalyst Formulation on Vehicle Emissions With Respect to Gasoline Fuel Sulfur Level

1999-10-25
1999-01-3675
Proposed emissions standards will require that emissions control systems function at extremely high efficiency. Recently, studies have shown that elevated gasoline fuel sulfur levels (GFSL) can impair catalytic converter efficiency. In this study, a variety of tri-metal catalysts were evaluated to determine if formulation changes could reduce emissions sensitivity to GFSL. Catalysts with elemental composition similar to an OEM, but with double the precious metal (PM) loading, were evaluated using 38 and 620 ppm GFSL. Doubling the PM loading significantly reduced catalyst sensitivity to sulfur. Doubling the rhodium loading, at the expense of the platinum loading, significantly improved NOx emission sulfur sensitivity.
Technical Paper

Measurement and Analysis of Commercial Vehicle Air Dryer Efficiency

1999-11-15
1999-01-3774
The measurement of pressure dew point is a well-known method of describing air quality, however this value seldom assists commercial vehicle OEM’s and operators in establishing specific air drying requirements for their vehicles. This paper describes the method and examines the results of using the dryer capacity method specified in SAE document J2384, section 5.2, for determining air dryer performance, and compares the results of various air-drying techniques and the impact on vehicle system design to give the most efficient solution. The paper further goes on to discuss how the drying capacity can also be influenced by the design of the air dryer to meet a wide range of vehicle applications both in Europe and North America. Since J2384 excludes continuous flow air dryers from the scope of the document, they will likewise be excluded from discussion here.
Technical Paper

Steering System Effects on On-Center Handling and Performance

1999-11-15
1999-01-3765
This paper reviews activities relating to understanding, and improving the on-center performance of heavy truck steering systems. Initially, the on-center steering performance characteristics for commercial vehicles were quantified. Steering wheel torque and angular position were the prime measurables. Graphical analyses of the on-center handling data were performed. To better understand the data, and to insure statistical significance, an algebraic model of the analyzed data was developed, with confidence intervals determined. The calculated system stiffness, as determined from the steering wheel data, was found to be a key discriminator between steering gears. System stiffness is a function of several component values, which were measured in the laboratory. Finally, to test the above findings, a correlation study of subjective driver impressions with measured steering gear characteristics and objective vehicle measures was performed.
Technical Paper

Intelligent DC Power Management System

1999-11-15
1999-01-3749
Most heavy-duty vehicles including trucks, tractors, buses, ambulances, refrigerated trailers, passenger vehicles, electric vehicles and boats have high amp Direct Current systems. Unlike the majority of components and systems in such vehicles, DC electrical systems have undergone very few major improvements in recent years. The Intelligent Power Management System discussed in this paper can offer significant improvements in the DC power management of such vehicles. The primary benefits of this system include: improved reliability of all electrical components, early warning of impending failures, extended service life, optimized generation, storage and use of power, and reduced maintenance cost and vehicle downtime. This paper will describe the Intelligent Power Management System, its design, applications and benefits.
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