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The field of motor vehicle rollover research and testing has been one of multiple and varied approaches, dating back to at least the 1930's. The approach has been as simple as tipping a vehicle over at the top of a steep hill ( Wilson et al., 1972 ), to as complex as releasing a vehicle from an elevated roll spit mounted to the rear of a moving tractor and trailer ( Cooper et al., 2001 and Carter et al., 2002 ). Presenter Peter Luepke, P Luepke Consulting

There are many macro drivers that are creating opportunities for transportation electrification. They include the environment, dependence on foreign oil, national security, battery technology and government incentives to name a few. In light of this growing momentum consumers will have choices to where they can charge ? at home, workplace or publicly. Electrical vehicle supply equipment will drive value throughout the supply chain ? installer, building owner, automaker, suppliers, utilities and consumers. Market acceptance will occur when consumer?s needs and wants are met. To meet these needs access to products through multiple channels will be required. Presenter Manoj Karwa, Leviton Manufacturing Co. Inc.

Vehicle aerodynamic development, drag reduction and fuel economy, handling and stability, cooling flows, surface soiling and water management, vehicle internal environment, tyre aerodynamics and modelling, aeroacoustics, structural response to aerodynamic loading, simulating the on-road environment, onset flow turbulence, unsteady aerodynamics, fundamental flow structures, new test methods and facilities, new applications of computational fluid dynamics simulation, competition vehicle aerodynamics.

Abstract Exhaust manifolds are one of the most important components on the engine assembly, which is mounted on engine cylinder head. Exhaust manifolds connect exhaust ports of cylinders to the turbine for turbocharged diesel engine therefore they play a significant role in the performance of engine system. Exhaust manifolds are subjected to very harsh thermal loads; extreme heating under very high temperatures and cooling under low temperatures. Therefore designing a durable exhaust manifold is a challenging task. Computer aided engineering (CAE) is an effective tool to drive an exhaust manifold design at the early stage of engine development. Thus advanced CAE methodologies are required for the accurate prediction of temperature distribution. However, at the end of the development process, for the design verification purposes, various tests have to be carried out in engine dynamometer cells under severe operating conditions.

Abstract Although ground grading is one of the most common tasks that hydraulic excavators perform in typical work sites, proper grading is not easy for less-skilled operators as it requires coordinated manipulation of multiple hydraulic cylinders. In order to help alleviate this difficulty, automated grading systems are considered as an effective alternative to manual operations of hydraulic excavators. In this article, a sliding mode controller design is presented for automated grading control of a hydraulic excavator. First, an excavator manipulator model is developed in Simulink by using SimMechanics and SimHydraulics toolboxes. Then, a sliding mode controller is designed to control the manipulator to trace a predefined trajectory for a grading task. For a comparison study, a PI controller is used to control the manipulator to perform a grading task following the same desired trajectory and the performance is compared with those obtained by the sliding mode controller.

Abstract This research developed methods for a virtual operator model (VOM) to learn the optimal control inputs for operation of a virtual excavator. Virtual design, used to model, simulate, and test new features, has often been limited by the fidelity of the virtual model of human operators. Human operator learns, over time, the capability, limits, and control characteristics of new vehicles to develop the best strategy to maximize the efficiency of operation. However, VOMs are developed with fixed strategies and for specific vehicle models (VMs) and require time-consuming re-tuning of the VOM for each new vehicle design. Thus, there typically is no capability to optimize strategies, taking account of variation in vehicle capabilities and limitations. A VOM learning capability was developed to optimize control inputs for the swing-to-pile task of a trenching operation. Different control strategies consisted of varied combinations of speed control, position control, and coast.

Vehicle aerodynamic development, drag reduction and fuel economy, handling and stability, cooling flows, surface soiling and water management, vehicle internal environment, tyre aerodynamics and modelling, aeroacoustics, structural response to aerodynamic loading, simulating the on-road environment, onset flow turbulence, unsteady aerodynamics, fundamental flow structures, new test methods and facilities, new applications of computational fluid dynamics simulation, competition vehicle aerodynamics.

Facing a competitive and globalized market and with increasingly demanding customers, companies must constantly seek the development of practices in the development of new products. One of the current practices is the adoption of modularity. In that sense, the objective of this paper is to conduct an analysis of this practice in a Brazilian company, which manufactures agricultural machinery. The applicability of modular design in current products is focused. Therefore, a case study approach has been chosen. First, a review of the scientific literature was conducted, followed by field research, for collecting data based on interviews with product engineers and technical documentation. The case study shows the applicability of the modular design concept in a combine header, by increasing the number of repeated components. The modular header approach facilitates the implementation of engineering changes and allows greater standardization of components.

Due to the diversity of Heavy Duty Vehicles (HDV), the European CO2 and fuel consumption monitoring methodology for HDVs will be based on a combination of component testing and vehicle simulation. In this context, one of the key input parameters that need to be accurately defined for achieving a representative and accurate fuel consumption simulation is the vehicle's aerodynamic drag. A highly repeatable, accurate and sensitive measurement methodology was needed, in order to capture small differences in the aerodynamic characteristics of different vehicle bodies. A measurement methodology is proposed which is based on constant speed measurements on a test track, the use of torque measurement systems and wind speed measurement. In order to support the development and evaluation of the proposed approach, a series of experiments were conducted on 2 different trucks, a Daimler 40 ton truck with a semi-trailer and a DAF 18 ton rigid truck.

The emergence of tougher environmental legislations and ever increasing demand for increased ride comfort, fuel efficiency, and low emissions have triggered exploration and advances towards more efficient vehicle gearbox technologies. The growing complexity and spatial distribution of such a mechatronic gearbox demands precise timing and coordination of the embedded electronics, integrated sensors and actuators as well as excellent overall reliability. The increased gearbox distributed systems have seen an increased dependence on sensors for feedback control, predominantly relying on hardware redundancy for faults diagnosis. However, the conventional hardware redundancy has disadvantages due to increased costs, weight, volume, power requirements and failure rates. This paper presents a virtual position sensor-based Fault Detection, Isolation and Accommodation (FDIA), which generates an analytical redundancy for comparison against the actual sensor output.

Radial piston units find several applications in fluid power, offering benefits of low noise and high power density. The capability to generate high pressures makes radial piston pumps suitable for clamping function in machine tools and also to operate presses for sheet metal forming. This study is aimed at developing a comprehensive multidomain simulation tool to model the operation of a rotating cam type radial piston pump, with particular reference to the lubricating gap flow between the pistons and the cylinder block. The model consists of a first module which simulates the main flow through the unit according to a lumped parameter approach. This module evaluates the features of the displacing action accounting for the detailed evaluation of the machine kinematics and for the mechanical dynamics of the check valves used to control the timing for the connection of each piston chamber with the inlet and outlet port.

Transport Canada, through its ecoTECHNOLOGY for Vehicles program, retained the services of the National Research Council Canada to undertake a test program to examine the operational and human factors considerations concerning the removal of the side mirrors on a Class 8 tractor equipped with a 53 foot dry van semi-trailer. Full scale aerodynamic testing was performed in a 2 m by 3 m wind tunnel on a system component basis to quantify the possible fuel savings associated with the removal of the side mirrors. The mirrors on a Volvo VN780 tractor were removed and replaced with a prototype camera-based indirect vision system consisting of four cameras mounted in the front fender location; two cameras on either side of the vehicle. Four monitors mounted in the vehicle - two mounted on the right A-pillar and two mounted on the left A-pillar - provided indirect vision information to the vehicle operator.

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.

Researches for automation of hydraulic excavators have been conducted for laborsaving, improved efficiency of operations and increased worker's safety improvement. Authors' final goal is to develop automatic digging system which can realize the high efficiency. Therefore, it is thought that appropriate digging control algorithm is important for the automation. For this goal, this paper shows a dynamics model of the backhoe excavator and simulations using such models. Detailed dynamic models are needed from the point of view of the control engineering. Authors evaluate effectiveness of automatic digging algorithm by simulation models. In this research, the linkage mechanism which contains the closed loops is modeled based on the Newton-Euler formulation, where motion equation is derived. Moreover, we apply a soil model for simulation, based on the two dimensional distinct element method (DEM), in order to reproduce reaction force from grounds.

Researches for automated construction machinery have been conducted for labor-saving, improved work efficiency and worker's safety, where a tracking control function was proposed as one of the key control system strategies for highly automated productive hydraulic excavators. An optimized digging trajectory that assures as much soils scooped as possible and less energy consumption is critical for an automated hydraulic excavator to improve work efficiency. Simulation models that we used to seek an optimized digging trajectory in this study consist of soil models and front linkage models of a hydraulic excavator. We developed two types of soil models. One is called wedge models used to calculate reaction forces from soils acting on a bucket during digging operation, based on the earth pressure theory. The other is called Distinct Element Method (DEM) model used to analyze soil behaviors and estimate amounts of soils scooped and reaction forces quantitatively.

This paper describes a method for optimization of engine settings in view of best total cost of operation fluids. Under specific legal NOX tailpipe emissions requirements the engine out NOX can be matched to the current achievable SCR NOX conversion efficiency. In view of a heavy duty long haul truck application various specific engine operation modes are defined. A heavy duty diesel engine was calibrated for all operation modes in an engine test cell. The characteristics of engine operation are demonstrated in different transient test cycles. Optimum engine operation mode (EOM) selection strategies between individual engine operation modes are discussed in view of legal test cycles and real world driving cycles which have been derived from on-road tests.

In this paper, the performance simulation model of a domestic self-dumping truck was established using AVL-Cruise software. Then its accuracy was checked by the power performance and fuel economy tests which were conducted on the proving ground. The power performance of the self-dumping truck was evaluated through standing start acceleration time from 0 to 70km/h, overtaking acceleration time from 60 to 70km/h, maximum speed and maximum gradeability, while the composite fuel consumption per hundred kilometers was taken as an evaluation index of fuel economy. A L9 orthogonal array was applied to investigate the effect of three matching factors including engine, transmission and final drive, which were considered at three levels, on the power performance and fuel economy of the self-dumping truck. Furthermore, the grey relational grade was proposed to assess the multiple performance responses according to the grey relational analysis.

Retaining the diesel combustion process but burning primarily natural gas offers diesel-like efficiencies from a natural-gas fuelled heavy-duty engine. This combustion event is limited by the injection pressure of the fuel, as this dictates the rate of mixing and hence of combustion. Typical late-cycle direct injection applications are limited to approximately 300 bar fuel pressure. The current work reports on tests for the first time at natural gas injection pressures up to 600 bar. The results show that significant efficiency and particulate matter reductions can be achieved at high loads, especially at higher speeds where the combustion is injection rate limited at conventional pressures. Increases in combustion noise and harshness are a drawback of higher pressures, but these can be mitigated by reducing the diameter of the nozzle gas holes to control the fuel injection rate.

New emission legislations applicable in the near future to sea-going vessels, off-road and off-highway vehicles require drastic nitric oxides emission reduction. A promising approach to achieve part of this decrease is charge air temperature reduction using Miller timing. However, it has been shown in literature that the reduction potential is limited, achieving a minimum in NOx emissions at a certain end-of-compression temperature. Further temperature reduction has shown to increase NOx emissions again. Some studies have shown that this increase is correlated to an increased amount of premixed combustion. In this work, the effects of pilot injection on engine out NOx emissions for very early intake valve closure (i.e. extreme Miller), high boost pressures and cold end-of-compression in-cylinder conditions are investigated. The experiments are carried out on a 3.96L single cylinder heavy-duty common-rail Diesel engine operating at 1000 rpm and at constant global air-to-fuel ratio.

In the last couple of decades, countries have enacted new laws concerning environmental pollution caused by heavy-duty commercial and passenger vehicles. This is done mainly in an effort to reduce smog and health impacts caused by the different pollutions. One of the legislated pollutions, among a wide range of regulated pollutions, is nitrogen oxides (commonly abbreviated as NOx). The SCR (Selective Catalytic Reduction) was introduced in the automotive industry to reduce NOx emissions leaving the vehicle. The basic idea is to inject a urea solution (AdBlue™) in the exhaust gas before the gas enters the catalyst. The optimal working temperature for the catalyst is somewhere in the range of 300 to 400 °C. For the reactions to occur without a catalyst, the gas temperature has to be at least 800 °C. These temperatures only occur in the engine cylinder itself, during and after the combustion.