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The purpose of this paper is to examine the use of a surface mineralization process for general corrosion protection. More specifically, this paper describes the use of surface mineralization (SM) as a non-hazardous and environmentally benign alternative to cadmium plating and hexavalent chromate treatment for protecting fasteners from corrosion in off highway applications. An engineered surface is founded on a mineral-based product that forms a thin metal silicate surface fully involving the substrate metal. Completed laboratory cyclic testing of SM treated fasteners compared with cadmium plated and hexavalent-chromate treated fasteners to 180 cycles using the GM 9540P protocol have demonstrated a significant increase in corrosion resistance of components protected by the SM process.

Most pieces of mobile equipment (machines) produce an audible signal to indicate movement in the rearward direction. This signal is intended to alert nearby personnel of the potential danger associated with the machine moving in a direction where the operator may not be able to see people or objects in the machine path. Anyone who has been on or near a construction site recognizes the familiar “beep…beep…beep…” of this signal as the backup alarm. To be effective, the backup alarm must be discernible, timely, and relevant to those people where a reaction is intended. As machine designers respond to various sound directives for reducing sound emissions (including the backup alarm), the performance of the backup alarm is receiving special attention. An emerging solution is an alarm capable of sensing ambient sounds and producing an audible signal proportional to the sensed sound levels-a self-adjusting backup alarm.

E-spring is an optimized trend of springs for vehicle suspension systems. Experimental and transmissibility analyses of laminated fibrous composite E-springs are conducted. The mechanical and frequency-response-based properties of these springs are investigated experimentally at both of the structural and constitutional levels. Thermoplastic-based and thermoset-based fibrous composite structures of the E-springs are modified at micro-scale with various additives and consequently they are compared. The experimental results reveal that additives of micrometer-sized particles of E-glass fibers as well as mineral clay to an ISO-phthalic polyester resin of the composite E-spring can demonstrate superior characteristics. The transmissibility analysis of laminated fibrous composite E-springs reveals superior frequency ratio.

Suspension systems are designed by considering comfort and durability issues. If suspension systems are analyzed from the view point of acceleration and force transmission, two design criteria are obtained that can be used in optimum design of these suspension systems. For individual links of these suspension systems, these criteria are minimum transmissibility condition and percussion center of the links, which are derived through kinematical analysis. While minimum transmissibility condition can be imposed geometrically, location of percussion center of a link can be optimized by using finite element model of the link. It is shown that accelerations and reaction forces that are transmitted to the chassis of the vehicle can be reduced by considering these issues.

Measurements of soot and SOF emitting from automobile engines by conventional gravimetric method and soxhlet extraction method are difficult and time-consuming processes. The composition in the filter substrate may change during time-consuming analysis. Therefore an accurate and real time measurement method for particulate matter is the key demand for automobile industry. This paper describes a new concept for analyzing PM, which includes measurement of soot and SOF separately, as well as the total PM emission from automobile engine continuously. The concept comprises of the real-time measurement of soot emission with a diffusion charger (DC) combined with a specific dilution system. A differential flame ionization detector with separate sample line temperatures (47°C and 191°C), have been applied for the SOF measurement. The total PM is then expressed as the sum of soot and SOF mass.

In support of NHTSA's studies of heavy truck brake types and their effects on vehicle stopping performance and stability, the NHTSA Vehicle Research and Test Center (VRTC) has evaluated four foundation brake types on their Greening Brake Dynamometer. Several sample assemblies of each type of brake were tested to better understand variability. Braking tests were run under the “Laboratory Test Procedure for FMVSS 121D Air Brake Systems - Dynamometer” (TP- 121D-01) procedures. Afterward, the test scope was expanded to include higher speeds and higher severity conditions than those specified Test Procedure. This paper reports on the differences in braking effectiveness between two traditional S-Cam air brake types and two recently introduced Air Disc brake types. Burnish procedure trends are briefly discussed and compared. Responses of the pneumatic brakes to both constant-pressure and dynamic inputs are also compared and discussed.

In response to the appearance of formal regulations, CFR part 1065 subpart J, a new in-use emission measurement system was developed, the OBS 2000. The OBS 2200 uses partial-vacuum analyzers. The heated flame ionization detector (HFID), heated chemiluminescence detector (HCLD) and heated non-dispersive infrared analyzer (HNDIR) are all upstream of the sample pump. This design decreases the response time of the analyzers, lowers power consumption and minimizes the overall dimensions of the system by avoiding the use of a heated sample pump. The size of the heated zones is also minimized to reduce power usage. Typical power consumption of analyzer unit is less than 500 W. The overall dimension of the main unit is 350mm (W) × 330mm (H) × 500mm (D). Analyzer linearity checks as required by new regulations [1] for all available ranges will be presented along with cut point accuracies relative to full scale and percentage of point.

Axiomatic Design is a principal based method to help reduce or eliminate conceptual vulnerabilities early in the design process by clearly linking function requirements to design parameters creating a hierarchy of Design Matrices which are then evaluated relative to two axioms. This paper illustrates the use of Axiomatic Design methods to design a Smart Inlet Control Valve for heavy-duty air brake compressors operating with highly turbocharged inlet air. The example application shows how Axiomatic Design links with two other Product Development tools - Failure Modes and Effects Analysis and Taguchi methods.

Virtual proving ground (VPG) simulations have been popular with passenger vehicles. VPG uses LS-DYNA based non-linear contact Finite Element analysis (FEA) to estimate fully analytical road loads and to predict structural components durability with PG road surfaces and tire represented as Finite elements. Heavy vehicle industry has not used these tools extensively in the past due to the complexity of heavy vehicle systems and especially due to the higher number of tires in the vehicle compared to the passenger car. The higher number tires in the heavy vehicle requires more computational analysis duration compared to the passenger car. However due to the recent advancements in computer hardware, virtual proving ground simulations can be used for heavy vehicles. In this study we have used virtual proving ground based simulation studies to predict the durability performance of a trailer suspension frame.

Reduction of alternator noise has become an increasingly important task in automotive industry as requirements for passenger compartment comfort increase, and other components such as the engine, exhaust system, etc. are made quieter. However, the aim of this study is to identify the noise sources of a numbers of alternator bands and to develop design guidelines to reduce the overall noise levels sacrificing the specified performance. With these guidelines, design engineers can reduce alternator noise effectively. To identify mechanical, aerodynamic and electromagnetic noise generation mechanisms, the alternator was reconfigured in many different ways, so as to separate each individual noise source. Noise generated by each configuration running at different speeds was measured, and its characteristics were analyzed. A special test stand was designed and fabricated, and tests were conducted in the automotive laboratory.

This paper studies the proportional directional control valves design influence on the energetic behavior of a mid-power compact excavator. In particular, with reference to the hydraulic circuit actuating the primary workgroup, in the paper the hydraulic power metering performed with the boom cylinder proportional control valve is studied, and some design solution useful in reducing both the hydraulic power dissipation, and the power absorption from the machinery prime mover are highlighted. The analysis, experimentally performed for different operating conditions, is carried out highlighting the influence of a metering configuration both on the supply pressure modulation and on the flow-rate supplied to the actuator.

In an effort to reduce the dry stopping distance required for heavy trucks, it is imperative to increase the effectiveness of the foundation brake systems. Where brakes are torque limited, increasing the brake output can be obtained by increasing brake size, chamber size, slack length, and friction of the braking materials. Looking just at the aspect of foundation brakes, the majority of current tractor and trailer brakes are of the S-Cam and Drum type. Two commercially available alternatives that produce higher output are Air Disc brakes and larger sized S-Cam brakes. Using one type, or a combination of these brakes (discs and drums on different axles) warrants a comparative study. The goal is to improve the effectiveness of the brake system, while maintaining or improving upon vehicle stability during braking. NHTSA's Vehicle Research and Test Center recently completed a brake test study of the effectiveness and stability characteristics of tractor and trailer combinations.

The hybrid electric vehicle is currently changing the automotive market at an impressive rate. While not as highly publicized, the transit bus market is being transformed at an equal rate. As these markets move forward, the school bus market remains largely unchanged. As an unchanged market, there is still the opportunity to optimize a hybrid vehicle platform for school buses. This study begins the modeling process of an existing class C school bus and investigates the potential that both series and parallel hybrids hold to reduce fuel consumption and emissions for a school bus. The primary focus of this study is to investigate the potential benefits of adding an electricity grid interconnection to hybrid electric school buses, allowing them to add to the hybrid potential with a pre-charged battery pack from the electric utility grid. These vehicles are known as plug-in hybrids.

A Decision Network is an explicit model of the Thinking Breakdown Structure of any complex scientific, engineering, or societal challenge. Each node in the Decision Network represents a fundamental question that must be answered, i.e. a choice that demands a solution. A Decision Network provides an integrated Decision Management framework for any Systems Engineering effort that links business, technology and design choices. Effective Decision Management is the key to Systems Engineering success. This paper will provide an overview of a decision-centric approach to Systems Engineering built around Decision Networks. Lessons learned through the use of Decision Networks in other industries will be extrapolated for use in vehicle Systems Engineering.

This paper describes the implementation effort behind adding a pair of suspension links between the axle and frame of a light truck with a Hotchkiss-type suspension. These links, referred to as anti-windup bars (or traction bars), were introduced into an existing system to improve NVH performance; however, doing so required modifications to maintain other vehicle attributes, including vehicle safety and durability life. The authors address the management of these attributes and related design decisions for the components involved, focusing on the conflicting requirements involved. Physical vehicle testing, using design revisions recommended by Finite Element (FE) simulations, was performed to confirm component performance and related system behavior. Test results suggested improvements to the FE models that were required to more closely approximate the vehicle's behavior.

In this paper a lumped parameters numerical model is reviewed to study the meshing process of external gear pumps and motors, with the aim of highlighting the influence of some geometrical design parameters and operating conditions on inter-teeth volumes pressures. The inter-teeth space is modeled adopting a two-volume approach, properly tailored both for the pump and for the motor units behavior description. In both cases, the communications between the interconnected inter-teeth volumes and the high and low pressure ports are sketched as variable equivalent turbulent restrictors; flow areas have been determined as functions of the gears and of the meshing grooves main design parameters. The inter-teeth pressures, and the leakage flows, are calculated solving the incompressible and isothermal continuity equation, contemporarily applied to both volumes and properly combined with the classical turbulent orifice equation.

This paper discusses implementing 120V AC on trucks. We will discuss the following topics: A. A brief history of AC generation B. AC power requirements on trucks C. Issues and concerns D. Summary and conclusion

A revolution in mobile hydraulic equipment is occurring. Conventional hydraulic spool valves with hydromechanical pressure compensators are being replaced by valve assemblies with four valve independent metering with electronically-controlled pressure compensation. In the system described here, two of the four independent valves are active during metering. This new topology offers significant advantages due to the two degrees of freedom provided. One of these degrees of freedom used to control velocity is more fully described in a related paper. In this paper, it is shown how the second degree of freedom can be used to control pressure in an actuator workport or minimize velocity errors due to valve coefficient errors. Workport pressure control can be used to limit maximum or minimum workport pressures (e.g. prevent cavitation). Given certain criteria, an optimal solution can be obtained.

This paper discusses a statistical approach to the analysis of power consumption in Class 8 Sleeper Trucks. We will also make recommendations for the electrical design of Class 8 truck. The paper discusses past electrical devices, why device use has increased, and how electrical system design has changed to keep up with truck evolution. We will analyze the electrical loads on the vehicle. This will include a list of cab and sleeper loads common to heavy trucks, current draws, and the advantages this analysis will give to the electrical designers. The analysis also provides peak and average electrical consumption for typical trucks, which helps in optimizing the associated electrical design of a truck power system. Six Sigma is used to analyze the electrical load data. Six Sigma is a systematic, data driven approach to statistically describe a process. Our process of designing an electrical system will greatly benefit from the use of this tool.

The sloshing behavior of a liquid cargo is an issue that needs to be taken into account when evaluating the dynamic performance of tankers. In general, hazardous liquid materials require a free volume into the tank to absorb thermal expansion changes; therefore, tank has to be filled partially. Under that condition, sloshing is produced at the liquid surface which interacts with container walls generating forces that affect the vehicle’s behavior. In this work, results obtained from experimental tests carried out in a scaled elliptical-transversal-section tank for different filling levels, baffles’ geometries, and baffles’ arrays are presented. Tank is instrumented so that longitudinal forces due to sloshing can be measured when tank is suddenly stopped. The analysis of the results allows identifying the best baffle configuration to be applied in order to attenuate the longitudinal sloshing generated when the vehicle is moving on highways.