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A method has been developed which allows prediction of the field performance of structural components based on prototype vehicle test procedures and results. Component designs can then be optimized by selecting prototype durability test objectives which more accurately reflect actual field usage. This procedure, which is based on fatigue damage calculations from component strain histories, has been successfully applied to non-safety related body, frame and suspension structural components of light trucks and vans.

The Vehicle Energy Consumption calculation Tool (VECTO) is used for the official calculation and reporting of CO2 emissions of HDVs in Europe. It uses certified input data in the form of energy or torque loss maps of driveline components and engine fuel consumption maps. Such data are proprietary and are not disclosed. Any further analysis of the fleet performance and CO2 emissions evolution using VECTO would require generic inputs or reconstructing realistic component input data. The current study attempts to address this issue by developing a process that would create VECTO input files based as much as possible on publicly available data. The core of the process is a series of models that calculate the vehicle component efficiency maps and produce the necessary VECTO input data. The process was applied to generate vehicle input files for rigid trucks and tractor-trailers of HDV Classes 4, 5, 9 and 10.

As a non-predictive model of the scavenging process, a generalized thermodynamic model has been suggested. This model can give a thermodynamic description for any possible scavenging process. Having specified a history of the scavenging process, this model is suitable for all scavenging systems including cross, loop and uniflow scavenging schemes. For the simplified isobaric and isochoric model with respectively constant coefficients of intake and discharge proportions during different scavengine phases, analytical solutions for this model have been obtained. From these, all existing models with the isobaric and isochoric assumptions can be derived.

During the past decades the public acceptance of the actual environmental legislation has gradually turned into an active support of the same. Test methods have anyhow become more cost heavy and time consuming, underlining the need of simplified tests with reasonable correlation to the legal methods. Generally, the emissions under static and semistatic load conditions are gradually eliminated, why the heavy pollution now comes from transient periods of the driving pattern. Consequently a transient test procedure must satisfy the quality requirements on a short test applicable to vehicles from cars to heavy trucks and busses. The INertia COLLection system described here is developed to enable low cost and well repeatable measurements of the emission characteristics of engine systems in light and heavy vehicles under transient load. The system is easy to adopt and does not need any chassis dynamometer.

The use of instrumentation on agricultural equipment slowly evolved from human observation of the operation of the equipment to a level of instrumentation which parallels that found on automobiles, and shared that automotive plateau for approximately 40 years. It has now embarked on a path which differs from that of the automobile. These differences are now openly competitive within the agricultural industry in both the choice of display technology and in function selection. This paper reviews both the early and modern agricultural instrumentation along with some of the unique functions now being monitored.

Abstract This article proposes a novel approach of a hybrid system of physics and data-driven modeling for accurately estimating the state of charge (SOC) of a battery. State of Charge (SOC) is a measure of the remaining battery capacity and plays a significant role in various vehicle applications like charger control and driving range predictions. Hence the accuracy of the SOC is a major area of interest in the automotive sector. The method proposed in this work takes the state-of-the-art practice of Kalman filter (KF) and merges it with intelligent capabilities of machine learning using neural networks (NNs). The proposed hybrid system comprises a physics-based battery model and a plurality of NNs eliminating the need for the conventional KF while retaining its features of the predictor-corrector mechanism of the variables to reduce the errors in estimation.

The object of this paper is to review developments taking place in Europe on truck transmission design. The existing design principles used in synchronized mechanical transmissions are reassessed. A new approach where the main emphasis is given to synchronizer duty is described. The paper also discusses the logical extension of the use of stepped transmissions into semiautomatic versions and the possibilities of stepless transmissions.

Biofuel can enable a sustainable transport solution and lower greenhouse gas emissions compared to standard fuels. This study focuses on biodiesel, implemented in the easiest way as drop in fuel. When mixing biodiesel into diesel one can run into problems with solubility causing contaminants precipitating out as insolubilities. These insolubilities, also called soft particles, can cause problems such as internal injector deposits and nozzle fouling. One way to overcome the problem of soft particles is by filtration. It is thus of great interest to be able to quantify fuel filters’ ability to intercept soft particles. The aim of this study is to test different fuel filters for heavy-duty engines and their ability to filter out synthetic soft particles. A custom-built fuel filter rig is presented, together with some of its general design requirements. For evaluation of the efficiency of the filters, fuel samples were taken before and after the filters.

Today, active dynamic control systems for commercial vehicles, offering improved safety, are frequently discussed. Yaw stabilising systems are based on theories from passenger car implementation, yet roll stabilisation - probably introduced in the near future - requires increased knowledge of rollover mechanics. Static analysis, providing steady state rollover threshold (SSRT), is the most common approach. Nevertheless in a rolling vehicle, kinetic energy is always present, deteriorating roll stability, invalidating the analysis. A simple method determining the dynamic rollover threshold (DRT) is therefore introduces in this paper. DRT is the worst case measure of roll instability: the conditions are necessary but not sufficient for rollover.

An experimental methodology is proposed to measure the rollover propensity of road tankers when subjected to lateral perturbations derived from steering manoeuvers. The testing principle involves subjecting a scaled down sprung tank to the elimination of a lateral acceleration, to analyze its rollover propensity as a function of various vehicle's operational and design parameters. Initial acceleration is generated through putting the scaled tank on a tilt table supported by a hydraulic piston. The controlled release of the fluid in the hydraulic system generates a perturbation situation for the tank, similar to the one that a vehicle experiences when leaving a curved section of the road and going to a straight segment. Durations for the maneuver and initial tilt angles characterize both the corresponding intensities of the steering maneuver.

Abstract The 2010 Environmental Protection Agency (EPA) Emission Standard for heavy-duty engines required 0.2 g/bhp-hr over certification cycles (cold and hot Federal Test Procedure [FTP]), and the California Air Resources Board (CARB) standards require 0.02 g/bhp-hr for the same cycles leading to a 90% reduction of overall oxides of nitrogen (NOx) emissions. Similar reductions may be considered by the EPA through its Cleaner Trucks Initiative program. In this article, aftertreatment system components consisting of a diesel oxidation catalyst (DOC); a selective catalytic reduction (SCR) catalyst on a diesel particulate filter (DPF), or SCR-F; a second DOC (DOC2); and a SCR along with two urea injectors have been analyzed, which could be part of an aftertreatment system that can achieve the 0.02 g/bhp-hr standard.

A long standing problem with heavy vehicle stability has been rollover. With the higher center of gravity, heavier loads, and narrower tracks (as compared to passenger vehicles), they have a lower rollover stability threshold. In this paper, a rollover stability control algorithm based on a two-degrees-of-freedom (DOF) and a three-DOF vehicle model for a two-axle truck was developed. First, the 3DOF model was used to predict the future Lateral load Transfer Rate (LTR). Using this LTR value, the dynamic rollover propensity was estimated. Then, a robust output feedback gain control rollover stability control algorithm based on the combination of active yaw control and active front steering control was developed. A H₂/H∞/poles placement multi-objective control strategy was developed based on the 2DOF reference model.

The use of computer simulation of vehicle dynamics as a development tool has come into its own over the past few decades. “Simulated” testing on a computer makes possible a degree of control and repeatability that allows the automotive engineer to determine the influence of design variables on different aspects of dynamic performance in ways that would be difficult or impossible by experimental methods. One of the software tools receiving wide acceptance for simulating trucks and combination vehicles is Truck-Sim™. The attraction of this program arises in part from its foundation of truck modeling methods developed at the University of Michigan Transportation Research Institute over the past two decades, and the use of an advanced graphical user interface to make the software both easy to understand and easy to use by design and development engineers.

This is an assessment of United States High Speed Guided Transit (HSGT) systems policy, vision, goals, and magnetic levitation development and commercialization technology. It includes a historical review of past magnetic levitation vehicle developments, a review of the present status of MagLev trains, and an outline of future conventional (EML) Electro Magnetic Levitation for speeds under 400 km/h; and, (SC) Super Conductive (EDL) Electro Dynamic Levitation for subsonic speeds approaching 900 km/h. Magnetic levitation transit technology has been under development in America since the United States Congress passed the 1965 High Speed Guided Transit Act (HSGT) which authorized the Department of Transportation to fund HSGT projects. Since this initial effort focused attention on the potential of the magnetic levitation concept for very high speed transit applications, this technology has been an ongoing development in Europe and Japan.

Review of various construction, equipment and organization factors considered in the design of new plant facility for fabrication of prototype earthmoving vehicles. Emphasis on eliminating existing problems and maximizing plant efficiency.

This paper provides a review of the solubility parameter theory and its application to predicting elastomer/fluid compatibility. Emphasis is placed on describing the theory and translating the results of swell data into a more easily understood method than has previously been used. Numerous solubility parameters arc presented as well as swell test details. The swell data results are then used to determine solubility parameters which, upon comparison with other fluid or elastomer solubility parameters, determine compatibility. This procedure is especially important because it enables the results of swell tests to be used to identify elastomer/fluid compatibility of molecularly complex fluid additives or special elastomer mixtures.

Measurement of emissions from small utility engines has usually been accomplished using steady-state raw emissions procedures such as SAE Recommended Practice J1088. While raw exhaust measurements have the advantage of producing modal exhaust gas concentration data for design feedback; they are laborious, may influence both engine performance and the emissions themselves, and have no provision for concurrent particulate measurements. It is time to consider a full-dilution procedure similar in principle to automotive and heavy-duty on-highway emission measurement practice, leading to improvements in many of the areas noted above, and generally to much higher confidence in data obtained. When certification and audit of small engine emissions become a reality, a brief dilute exhaust procedure generating only the necessary data will be a tremendous advantage to both manufacturers and regulatory agencies.

The study of heavy vehicles rollover prediction, especially in algorithm-based heavy vehicles active safety control for improving road handling, is a challenging task for the heavy vehicle industry. Due to the high fatality rate caused by vehicle rollover, how to precisely and effectively predict the rollover of heavy vehicles became a hot topic in both academia and industry. Because of the strong non-linear characteristics of Human-Vehicle-Road interaction and the uncertainty of modeling, the traditional deterministic method cannot predict the rollover hazard of heavy vehicles accurately. To deal with the above issues, this paper applies a probability method of uncertainty to the design of a dynamic rollover prediction algorithm for heavy vehicles and proposes a novel algorithm for predicting the rollover hazard based on the combined empirical model of reliability index and failure probability.

A Department of Energy funded research project currently in the final stages of completion has resulted in a web-based tool that gives non-expert users the ability to add aerodynamic devices to a CFD model of a single bogie trailer and generalized tractor model. This model was used to assess the aerodynamic performance of skirt geometries. The skirts were defined using 5 independent geometric parameters and 2 installation parameters. These parameters allow enough freedom in the geometry definition to capture the shape and installation position and angle of a wide number of commercially available skirts on the market today. Using a Design of Experiments approach, the aerodynamic drag response of the truck and trailer to any parametric change in the skirt geometry has been determined across a range of yaw angles.

The objective of this paper is to delineate the importance of pictures, i.e., graphical models, in documenting and communicating the high level functionality of a complex system, primarily for embedded software requirements and specifications. An overview is given of various graphical techniques and methodologies for modeling complex systems. The aspects (advantages and disadvantages) relating to different categories of modeling are outlined. Discussion of complex systems extends beyond the functional/software aspects of product design to both process and project modeling. The author shares personal observations and experiences with modeling, and tools used.