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This paper presents the experience of Ford Motor Company and Hitachi Metals Ltd., in the development and design of the exhaust manifolds for the new 1997 Ford 6.8L, Vl0 gasoline truck engine. Due to the high-exhaust temperature 1000 °C (1832 °F), heat-resisting nodular graphite irons, such as high-silicon molybdenum iron and austenitic iron with nickel cannot meet the durability requirements, mainly thermal fatigue evaluation. The joint effort by both companies include initial manifold design, prototype development, engine simulation bench testing, failure analysis, material selections (ferritic or austenitic cast steel), production processes (casting, machining) and final inspection. This experience can well be applied to the design and development of new cast stainless-steel exhaust manifolds in the future. This is valid due to the fact that US EPA is requiring all car manufacturers to meet the new Bag 6-Emission Standards which will result in increased exhaust gas temperature.

A mathematical model has been developed to transfer Chassis Dynamometer (CD) test cycles for heavy duty vehicles to the equivalent Engine Dynamometer (ED) test cycles. The model assumed a generalized drivetrain layout, and a variable drive line efficiency. An interactive computer code was written to represent the mathematical model for different drivetrain systems. Several CD test cycles were used to obtain equivalent ED test cycles for a sample based upon an urban bus equipped with an automatic transmission. Results showed the possibility of simulating CD test cycles with equivalent ED test cycles for heavy-duty urban buses under certain assumptions.

Light-emitting diodes (LEDs) have been used for some time in interior vehicle applications such as instrumentation panels, but it has only been within the past five years that they have become viable for exterior lighting. This paper provides an overview of LED technology and the significant economic and performance advantages it offers compared with incandescent lights. It traces the evolution of the technology from its commercial introduction nearly 30 years ago through the latest advances in efficiency and color. Also addressed are specific issues relating to its application to trucks and buses and the challenges arising from developing lighting systems that are designed to last for the lifetime of the vehicle. The appendix provides a methodolgy for calculating return on investment (ROI) in LED lighting.

The design of a crew cab pickup for international truck markets is described. It is based on North American Pickup and Utility models. The design meets market and regulatory requirements for international use while providing flexibility in models and options. Engineering resources from North America and Brazil supported the design, build, development, and testing. Strategies used to exploit the existing pickup and utility designs will be explained. Specific packaging and structural challenges will be reviewed. Basing the design on an existing vehicle reduced design and tooling, while constraining the design solutions. Concurrent engineering of all variants of a platform would optimize the design.

In the past, all known, compact pickup truck structures have been limited to the use of two doors to allow for access to the interior regions of the cab. This paper will address the issue of locating a side access panel to an existing vehicle structure, the development criteria used for the panel hinges, the integration of the safety belt system and the advantages of the interior trim attachment methods. Examination will include a review of specific design considerations used to meet governmental and consumer requirements.

Examples of ceramic circuits, mainly advanced electronic controller systems, designed to meet the needs of highly-integrated engine and vehicle control applications are presented. The elements of a strategy designed to meet the challenges presented by future integration requirements are discussed. Brief descriptions of the contributing technologies, plus an assessment of their current and projected capabilities are included. A road map for the development of this advanced ceramic thick film technology is presented.

This paper reviews the evolution of vehicular diesel engines, with particular attention to the major components affecting the power density, fuel economy and emissions, such as the cylinder head, valve train, combustion and injection systems. The operational inter-relationship between these systems is analyzed, with examples of present engines. Recent design improvements with gasoline engines are discussed, pointing-out certain aspects applicable to diesels. The paper concludes that by combining further-advanced systems with some of the best existing technologies, the next generation of “300 and 400 Series” engines intended for mid-range truck applications in Classes 4 to 6 could become a major export item.

Modern commercial vehicles must increasingly meet the requirements of economic efficiency, environmental protection, legislation and of the specific application. The Electronically-Controlled Rear Axle Steering System ZF RAS-EC™ makes an important contribution towards this and offers a basis for completely new approaches in the development of commercial vehicles.

A robust control method applied to a DC-motor the actuator of a steering system installed on a radio-controlled multiloader truck is developed Requirements for the control system are robustness and stability against disturbances and change in plant characteristics, and rapid and accurate response to steering commands To comply with these requirements, we applied a robust model matching (RMM) control method to the steering actuator Results of simulation analyses and a hardware-in-the-loop simulation show the effectiveness of this control method

The driving performance of a vehicle with front wheel steering system is enhanced by controlling the gain and/or phase-lag characteristics. A vehicle with rear axle steering system has an even or higher effect than that. The compliance steer control effect in mechanical system is the key technology for enhancing the on-center stability Driver's error compensating system by steering and/or brake system control will be in future, and the manual and automonous control hybrid driving system will follow it.

Recent surveys of customer satisfaction with full size pickup trucks have raised the standards for passenger comfort and refinement of such vehicles. Customers for this type of vehicle demand performance levels for attributes such as NVH, ride, and handling that previously belonged to luxury passenger cars. Along with the increased passenger comfort, full size pickup trucks must retain a tough image and be as durable as the previous generation trucks. The challenge is to design for NVH performance that can match and surpass many well behaved and “good” NVH passenger cars without any compromise in durability performance. One aspect of “good” NVH is a steering wheel which is free from vibration. As part of the development of a new design for a full sized pick up truck, an NVH subjective rating of 8-9 (10 is maximum) was targeted for the design of steering column/ instrument panel assembly.

The intent of this paper is to shed new light on the critical need to establish a new industry standard for heavy vehicle stability and control No attempt is being made to criticize what has gone on before, but rather to present an enlightened overview of the major cause of Driving Fatigue, and the need for a fundamental change in how the automotive design community addresses this universal heavy vehicle steering and control problem This paper is written to be more easily understood by those not schooled in the art It will unmask the mystery of steering geometry and focus on the few key elements that cause most of the directional stability problems

Rear axle steering systems electronically controlled and hydraulically actuated are discussed for commercial vehicles. With these steered axles, the major objective is to improve the manoeuvrability of these vehicles. With the aid of the steering strategy “Rear end Swing-out Compensation” it will be assured, that in two-axle, all-wheel steering trucks dangerous rear end swing-out effects, occuring primarily in low speed ranges, will not take place. In addition, it is possible to enhance the dynamic stability of two-axle trucks while braking on split adhesion road surfaces with the aid of specific control algorithms. Furthermore, the application of a rear axle steering system can suppress dangerous lateral oscillations of centre-axle trailers.

Integrated Product Development (IPD) focuses on the integration of people, process and technology to achieve best-in-class product development. Best-in-class means a development practice that provides the optimum values of cycle time, cost and quality for both the customer and the manufacturer. Typical Integrated Product Development (IPD) projects measure benefits using two indicators: the reduction of Engineering Change Notices (ECNs) and the reduction of warranty costs. While these metrics are excellent long term indicators of IPD benefit attainment, in most of the organizations I have worked, feedback to management on IPD progress must be measured monthly or quarterly. Without an ongoing status of the IPD project's benefits, momentum and participation in the effort will wane over time, and become another “improvement plan of the year” at the manufacturer.

The objective of this paper is to introduce to the trucking industry an innovative approach that will significantly increase the life and reliability of their windshield wiper systems. The endurance of a windshield wiper system is dramatically reduced when operated in the intermittent mode. The motor's integral commutator switch opens a highly inductive load and closes a short circuit across the winding during each cycle. Using the commutator switch as a sensor allows control by an expendable relay to extend system life and enhance maintainability. The sensor can also be used for “Wiper System Guard” or “Freeze Control” to detect non-rotation for quick, reliable shut down, which eliminates Thermal Cycling. Another feature requires the operator to control “Reset” for safe “Start-Up.” To simplify the determination of the wipers' repetition rate, a “switch” control technique is employed to increase operator functionality based on “need” to see through a windshield.

Ride quality of heavy duty truck becomes important item, due to long distance transfer and long time driving This study describes how to determine and evaluate design parameters related to cab suspension system through time and frequency domain analysis The spring and damper-stiffness of the cab suspension system were optimized by two objective functions, which consist of cab pitching acceleration peak level and vibrational absorbed power Cab pitching is the main item which should be studied for ride quality In an attempt at optimizing, we made use of “Taguchi Method”,which was applied to experiments and simulation. We made truck cab model by use of DADS, which is dynamic analysis software,in order to find out the cab motions The results of simulation and test of a heavy duty truck gave us the optimum design parameters, which were verified and confirmed by real vehicle test

In this study, the enhancement of road friendliness of Heavy Goods Vehicle is investigated using two methods to control the resonant forces: (i) Determination of optimal asymmetric force velocity characteristics of the suspension dampers to control the wheel forces corresponding to the resonant modes; (ii) Optimal design of an axle vibration absorber to control the wheel forces corresponding to the unsprung mass resonance mode. An analogy between the dynamic wheel loads and ride quality performance characteristics of heavy vehicles is established through analysis of an in-plane vehicle model. A weighted optimization function comprising the dynamic load coefficient (DLC) and the overall rms vertical acceleration at the driver's location is formulated to determine the design parameters of the damper and absorber for a range of vehicle speeds. The results show that implementation of tuned axle absorbers can lead to reduction in the DLC ranging from 11.5 to 21%.

Evaluating heavy truck suspensions for road friendliness and ride quality is a complex challenge An experimental study has been conduced to explore various options for evaluating suspension performance The methods examined use laboratory equipment and focus on evaluating suspension performance without the influence of the whole vehicle The experimental program found that “in phase sinusoidal frequency sweep” of constant amplitude produced clear differentiation of suspension response

The present state of knowledge on the handling behavior of truck-dolly-trailer systems is based on parametric studies made through simulation of eigne value analysis. Any convincing study using the equations to the stability boundaries have not been reported so far due to algebraic complexities. A detailed planar mathematical model for various design configurations of the tractor triaxle trailer combination, the tractor quadaxle trailer combination and the doglogger truck is developed. Furthermore, a kinematic and dynamic analysis of log hauling combination trucks, incorporating a sliding drawbar is carried out and the governing equations for planar yaw motions are derived. Using the computer simulation model, the directional performance and yaw stability of articulated vehicles are studied through the transient and harmonic response analysis. Finally, a parameter sensitivity study is carried out for different variables involved in the computer simulation model.

The traction effects of water depth, speed, tread wear, inflation, and load on typical 295/75R22.5 truck tires have been examined in a set of designed experiments conducted on a single pavement. The results have been typified in terms of regression models of aligning moment and lateral force at 4 degrees slip angle plus peak longitudinal force and longitudinal force at slide during braking. The effects of the principal parameters are catalogued. An approximate idea of the effect of the operational and tread wear state parameters on the ability to control vehicle motion is provided within the discussion.