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High definition (HD) maps can provide comprehensive and accurate knowledge of the environment for highly autonomous vehicles. However, HD maps have large data volumes, which pose high demands on data acquisition, analysis, and storage. To balance data volume and map definition between HD maps and low-accuracy road network maps, this paper is focused on the construction of lightweight HD maps for autonomous vehicles running with non-paved roads. Firstly, we introduce the representation of a lightweight HD map which contains several special elements, e.g., operating areas, parking lot, junction, borders, and centerlines, to describe the closed environment. Then, we propose a border generation algorithm and a border expansion algorithm to find the real border of the map and construct the drivable area. Meanwhile, a two-step method is proposed to extract the centerline of the road. An experiment is conducted to demonstrate the effectiveness of the proposed algorithms.

The increasing deployment of electronic equipment has intensified soldiers' need for lightweight, reliable, mobile and portable electrical power. Consequently, fuel cells are increasingly being deployed as power sources for defense organizations. Direct methanol fuel cells (DMFCs) provide logistical, security and functionality advantages compared to batteries alone, including virtually undetectable operation on the ground, onboard ground vehicles and unmanned aerial vehicles (UAVs). Unlike batteries, which store energy, DMFCs generate power by chemically converting methanol into electrical energy. SFC, which has sold more than 15,000 DMFCs in commercial applications, also is a leading provider of fuel cells for defense applications. This paper will discuss the development, evolution and use of DMFCs for those applications

Sustainable mobility has become priority in the wake of environmental concerns viz. emissions and depletion of fossil fuels. The growing demand for more fuel-efficient vehicles to reduce energy consumption and air pollution is a challenge for the automotive industry. Significant improvements in fuel economy can be obtained by weight reduction of vehicle as well as by improvements in engine and powertrain efficiency. If the vehicle body mass is reduced, there will be secondary mass reductions at the component level, particularly in the powertrain. Globally, automotive manufacturers have been engaged in efforts to develop lighter alternatives using aluminium alloys and other light weight materials, so as to reduce the energy requirement, improve the fuel consumption and reduce vehicular emissions. While the growth in mobility is growing rapidly in India, the installed base is still comparatively small, compared to the developed countries.

It has been widely reported that the overall vibration comfort performance of static and dynamics seats is strongly influenced by the biodynamic behaviour of the seated human body. The contributions of the seated occupant to the overall vibration attenuation of the coupled seat-occupant system are experimentally investigated as functions of the nature of excitation, static and dynamic properties of the seat, and the sitting posture. The study involved two different seats with natural frequencies in the vicinity of 1.5 Hz and 4 Hz, which would characterize the low natural frequency suspension as well as high natural frequency seats employed in automobiles and some industrial vehicles. The vibration isolation properties of the seats are evaluated with a rigid mass and two human subjects under different vibration excitations, including swept sine, broad-band random and standardized vibration spectra of selected vehicles.

A technique for evaluating ride quality as a function of cab isolation parameters is presented. The technique is applied to a cab over engine tractor to demonstrate limits of ride quality improvements.

Capacitive sensors have been used in industrial applications for over 25 years. Because of the advances in electronic instrumentation, the cost per unit application has decreased along with sensor size while the frequency response has increased along with the upper temperature limits to 1000°C typically. This is a more detailed discussion on the utilization of a linear capacitive reactance technique for non-contact measurements and how it relates its strengths to other technologies such as non-contact inductive, LED light, lasers, LVDT and others.

Research results by the Bureau of Mines are presented for a major of effort addressing a long term solution to problems associated with health and safety aspects of rotary drum mining machines. Proof-of-concept testing for the Bureau's Constant Depth Linear Cutting concept is described. The concept uses a triangular drum, mounted on an eccentric arm, cutting to a free face at low rpm. Preliminary comparative test results, for synthetic coal, between the linear cutting concept and a standard rotary drum show the linear cutting concept reduces entrained respirable dust by more than 95 pct, reduces -1/4-in-mesh product by more than 50 pct and, reduces horsepower by approximately 70 pct. These results are used to calculate the power requirements for a new, all diesel mining system to improve both miner health and safety, and productivity while reducing costs.

Simple solenoid plunger type electromagnets are commonly used in devices such as switches, relays, and solenoid valves (to name but a few). In most cases these are on/off applications where the plunger is moved from one extreme position (when turned on) to another (when turned off). In this paper a scheme is presented to enable positioning of a linear actuator based on two simple solenoids, a flat faced electromagnet, and a microprocessor. The paper describes the configuration and performance of such a system which uses pulsed signals from a microprocessor to activate the solenoids and the electromagnet. The plungers connected by a shaft in a push pull arrangement move in an axial direction while an electromagnet orthogonal to the shaft latches it at a desired position. An algorithm to control the input pulses to the solenoids and the electromagnet is developed and experimental results using this control scheme are presented.

Natural Gas Vehicle (NGV) engine technology is mainly based on a well-known and already established engine functioning principle, the Otto engine. The recent developments achieved and the OEMs push for this kind of technology clearly shows the confidence and reliability of this technology, especially when it comes to the use of compressed natural gas (CNG). For the above-mentioned reasons, the number of applications involving NGVs has increased worldwide. Environmental and economic reasons, on the whole, have been the main drive for this diffusion. Natural Gas chemical properties are an irrefutable proof of the advanced behavior, environmentally speaking, of a fuel that emits less CO₂ (due to its carbon-hydrogen balance when compared to other fuels) and less NOx and PM. In many countries, favorable taxation schemes have helped the development and entrance into the market of the NGV technology, especially for the light-duty vehicles.

This paper will establish the production quality for LNG vehicular fuel which will accommodate engine manufacturers' specifications for fuel quality at the engine. The potential degradation of the fuel from the time it leaves the production plant until it reaches the engine will be examined via a series of scenarios. The impact of engine manufacturers' fuel specifications will be translated into a vehicle fuel production specification which the consumer must utilize in selecting an acceptable fuel supplier.

Liquefied natural gas (LNG) is being developed as a heavy vehicle fuel. The reason for developing LNG is to reduce our dependency on imported oil by eliminating technical and costs barriers associated with its usage. The U.S. Department of Energy (DOE) has a program, currently in its third year, to develop and advance cost effective technologies for operating and refueling natural gas–fueled heavy vehicles (Class 7-8 trucks). The objectives of the DOE Natural Gas Vehicle Systems Program are to achieve market penetration by reducing vehicle conversion and fuel costs, to increase consumer acceptance by improving the reliability and efficiency, and to improve air quality by reducing tailpipe emissions. One way to reduce fuel costs is to develop new supplies of cheap natural gas.

Fuel level sender technology has evolved from simplistic wire-wound resistive senders to more advanced and reliable methods. Many options now exist that can provide a form, fit, and function equivalent sender that improves reliability, accuracy, etc. Current trends are leading toward senders that have no moving parts and will function in a variety of tank sizes and shapes, rather than requiring a different sender for each tank. This leads to reduced inventory requirements at the OEM level but presents unique design challenges. This paper will concentrate on fuel level sensing, but will provide relevant data on measurement of other automotive parameters.

Generally, noise will occur during steering with the hydraulic power steering system (hereinafter HPS). The noise producing in the rotary valve takes up a big proportion of the total one. To study the noise in the control valve, 2-D meshes of the flow field between the sleeve and the rotor were set up and a general CFD code-Fluent was used to analyze the flow inside the valve. The areas where the noise may be occurred were shown and some suggestions to silence the noise were given.

In the search for low greenhouse gas propulsion, the dual fuel engine provides a solution to use low carbon fuel at diesel-like high efficiency. Also a lower emission of NOx and particles can be achieved by replacing a substantial part of the diesel fuel by for example natural gas. Limitations can be found in excessively high heat release rate (combustion-knock), and high methane emissions. These limitations are strongly influenced by operating parameters and properties of the used (bio)-gas. To find the dominant relations between fuel properties, operating parameters and the heat release rate and methane emissions, a combustion model is beneficial. Such a model can be used for optimizing the process, or can even be used in real time control. As precursor for such a model, the current state of art of dual fuel combustion modelling is investigated in this work. The focus is on high speed dual fuel engines for heavy duty and marine applications, with a varying gas/diesel ratio.

The use of woven Teflon®* fibers to make self-lubricated bearings had its inception during the middle 1950’s. State-of-the-art has been to upgrade the bearings by using fiber blends to improve bonding, reliability, and adhesives for load capacity. But little attention has been made to the effects of the mating surface. These factors, such as finish characteristics, corrosion caused by the environment, and platings are as important as the bearing itself. Analysis of the mating surface is necessary if engineers are going to properly design maintenance-free equipment using high load capacity self-lubricated bearings.

Single row four point contact ball bearings are routinely used as slewing bearings to take heavy loads under a combination of eccentric axial load and radial load for applications such as excavators, cranes, etc. The calculation method of the equivalent loads for the slewing bearings was introduced in SAE 2010-01- 1892.1) However, in this previous paper the calculation method could not be applied when an axial load does not exist. The specific case with no axial load but with a moment due to an eccentric radial load is introduced in this paper. When the eccentric radial load is applied, the bearing takes ball loads on both sides of each raceway. As a result, simple equations were obtained to calculate the static and dynamic equivalent loads, as well as the safety factors and bearing lives for slewing bearings under this condition.

Single row four point contact ball bearings are routinely used as slewring bearings to take heavy loads under a combination of eccentric axial load and radial load for applications such as earth moving equipment, construction machinery, mining and handling machines, excavators and cranes, etc. The calculation method of the equivalent loads for slewring bearings was introduced in SAE 2006-01-35541 ) , but only dealt with the case in which the bearing takes a tilting moment due to combination load. In this paper, two additional load case conditions are analyzed: one is the case in which the bearing takes all ball loads only on one side of each raceway axially, and the second is the case in which the bearing takes ball loads radially on both sides of each raceway.

This paper evaluates estimations of modal coordinates from chassis damper displacements on heavy vehicles. The objective is to study to what extent relative displacements are sufficient as control input for semi active damping systems. The possibility to combine passive damping requirements at different driving conditions is furthermore investigated by studying damper displacements in the phase plane. For both objectives, vehicle simulations with a 3D - tractor semi trailer model are utilized. Results show that modal coordinate estimates based solely on relative damper displacements, during impact for transient load cases show significant discrepancies to actual motion. For subsequent free oscillations, modal coordinates may however be estimated this way. Phase plane plots are finally shown to be useful tools to illustrate conflicting demands on passive damping characteristic and to rate expected benefits from different damper techniques.

Modern safety regulations have led to the development of the load control valve which ensures that hydraulically supported loads will not fall in the event of a pipe failure. Pilot operation of these valves gives smooth control with low power consumption to maintain machine efficiency. To achieve this over a variety of applications has led to a wide range of valve options. Stemming from this development comes a new generation of valves, compatible with modern control systems. This gives the designers of mobile machinery the facility to further improve the efficiency of their machines while still meeting safety regulations.

This paper presents a load distribution-specific viscoelastic structural characterization of the Hybrid III 50th percentile male anthropomorphic test dummy thorax. The dummy is positioned supine on a high-speed material testing machine and ramp-and-hold tests are performed using a distributed load, a hub load, and a diagonal belt load applied to the anterior thorax of the dummy. The force-deflection response is shown to be linear viscoelastic for all loading conditions when the internal dummy instrumentation is used to measure chest deflection. When an externally measured displacement (i.e., a measurement that includes the superficial skin material) is used for the characterization, a quasilinear viscoelastic characterization is necessary. Linear and quasilinear viscoelastic model coefficients are presented for all three loading conditions.