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Lasers are used in the metal working industry for a variety of operations including welding, drilling, cutting, heat treating and marking. This paper will focus on the laser as a marking tool and the resulting effects, both physical and metallurgical, on bearing steels.

The growing use of laser processing within the automotive industry has generated interest in applying laser welding, cutting and surfacing to structures commonly used in off-road vehicle manufacture. The perceived benefits of applying laser welding technology are to reduce structural distortion, increase joint production rates, allow more accurate structures to be produced and enable mechanisation and automation. This paper will review the current status of high power laser technology, including CO2 and Nd:YAG lasers. The application of high power lasers to materials relevant to the fabrication of off-road vehicles will be presented covering details of joint design, joint quality, joint performance, quality assurance and economics.

Lateral control is an important part in the system of driverless mining trucks, which is used to realize accurate tracking of planned path. To solve the problem of poor accuracy of the existing single point preview algorithm, firstly, the lateral error model and the simplified truck dynamics model were built. The established truck dynamics model was verified and compared by simulation. The results show that the truck dynamic model in this paper retains accurate even at higher speed. Secondly, against the time delay of truck steering system, the cascade LQR-PID controller and MPC-MRAC controller are designed. The former resists the disturbance of steering time delay through the inner PID loop, while the latter realizes the adaptive control by establishing the steering model. Then, the dual-shift condition simulation was carried out by co-simulation model, and two controllers were compared and analyzed.

In the path following problem, a commercial vehicle has a delay of a hydraulic steering actuator and slow steering response accordingly. In addition, there are disturbances due to the harsh driving conditions of commercial vehicles. These disturbances may include uncertainties about actuator dynamic delay, modeling error and steering angle sensor offset. Designing a lateral controller with good performance that can overcome this problem is the key to successfully carrying out autonomous driving of commercial vehicles. Usually, it is difficult to consider disturbances with uncertainties in the geometric based control methods. Therefore, this paper proposed a lateral controller using feedback augmented disturbance observer for the commercial vehicle. First, a dynamics was modeled which can describe delay of the hydraulic actuator of the commercial vehicle. After that, a lateral controller was designed based on this dynamics model.

Due to the practice of lifting the rear suspension of heavy trucks, adopted by some end-users in Brazil, and in order to supply theoretical propositions to the manufacturers of suspension components for product improvement, this work describes stability and lateral dynamics tests simulations of a 4×2 rigid truck with 15000 kg of gross vehicle weight (GVW) and with changes in its originals leaf springs, predicting its dynamics responses in cornering and safety against rollover when unloaded and loaded at its GVWR limit.

In this paper, a new roll-plane hydraulically interconnected suspension (HIS) system is proposed to enhance the roll and lateral dynamics of a two-axle bus. It is well-known that the suspension tuning is of great importance in the design process and has also been explored in a number of studies, while only minimal efforts have been made for suspension tuning for the newly proposed HIS system especially considering lateral stability. This study aims to explore lateral dynamics and suspension tuning of a two-axle bus with HIS system, which could also provide valuable information for roll dynamics analysis. Based on a ten-DOFs lumped-mass full-car model of a bus either integrating transient mechanical-hydraulic model for HIS or the traditional suspension components, three newly promoted parameters of HIS system are defined and analyzed-namely the total roll stiffness (TRS), roll stiffness distribution ratio (RSDR) and roll-plane damping (RPD).

The Resolution 68/98 authorized the circulation of Long Combination Vehicles. Representative of freight vehicles evolution, these combinations should be observed taking into account their handling performance. Due to the quantity of articulations, they are subject to specific phenomena which affect their handling. The most relevant being “Rearward Amplification.” This concerns the increase in lateral deplacement of the last unit when compared with the first. The tractor-unit is subject to greater lateral acceleration, and has the potential to rollover. A study in rear amplification is essential for the evolution of freight vehicles, roads, road signals and in the training of drivers.

This work provides a theoretical analysis of the natural and forced lateral vibration in a driveline having a flexible coupling and universal joints. The analysis is specific to the front driveline common in many off-highway vehicles which usually consists of a flexible coupling at the engine flywheel, the driveshaft, and one or two universal joints. A torsionally flexible coupling is often needed in a front driveline to suppress torsional vibration. The problem is that most torsionally flexible couplings are also inherently flexible in their radial and cocking directions. These additional directions of flexibility, compounded by the presence of universal joints, can result in unexpectedly low lateral natural frequencies of the driveline. With a few axial dimensions, mass properties of the driveline, and stiffness properties of the flexible coupling, this work provides simple, closed-form calculations for the lowest lateral natural frequencies.

I would like to explain the cam grinding mechanism, control systems and grinding examples on the following two applications: 1. CNC/CBN external cam grinder to efficiently grind lobes of camshafts of various internal combustion engines. 2. CNC/CBN internal cam grinder to efficiently grind internal contour of hydraulic vane pump housing. In cam grinding area, CBN superabrasives and CNC control greatly contribute to the productivity, accuracy and flexibility required in automotive industry.

The different applications of trucks (short-, medium-, long distance haulage, construction site) lead to very different requirements to be met by the brake systems. Concerning transmission the air braking system has great advantages for trucks and has therefore prevailed. On the other hand the design of the brake system must consider the regulations. In Europe common regulations concerning braking systems have been brought out since 1972 and have superseded formerly national standards. So the set up of the braking system mainly with regard to the brake balance is dealt with under consideration of the european braking standards. The influence of braking on handling is very important. Therefore the behaviour of a truck and a tractor/semitrailer is discussed for braking in a straight line and in a turn.

Several lead-free alloys have been studied for potential use in electronics by the National Center for Manufacturing Sciences(NCMS) Lead Free Solder Consortium that ended in 1996. Since then, one of these alloys has been studied using an existing product in order to determine the viability of Lead Free Vehicle Electronics. Design, supply chain, manufacturability, and reliability data for the electronics components and system are a part of this paper.

As fuel costs and anti-idling legislation become more prevalent, the life cycle cost of the energy storage component of no-idle systems is becoming a critical consideration. Current systems employ up to four AGM lead-acid batteries, with a one year standard warranty. OEMs have reported higher than acceptable warranty claim levels and are interested in examining the potential advantages of alternative storage technologies. The use lead-carbon asymmetric hybrid battery/supercapacitor energy storage in the no-idle system application is examined through modified SAE J2185 cycle testing and other means - as these battery products have significantly improved rechargeability (charge acceptance) and longer life (up to 4x higher cycle life in deep cycle applications). The performance improvement is expected to provide shorter recharge times and reduced warranty claims. The technology could potentially offer means to a lower capacity alternator, thus reducing cost.

The study of Leadership embraces three main phases: 1) Trait theories, 2) Style theories, and 3) Situational theories. Each of these positions is reviewed in this paper. It is suggested that leadership is a process of using skills to analyze each situation to determine the appropriate leadership style. Suggestions are given to help the manager with this analysis to develop better leadership skills.

The implementation and development efforts of lean NOx trap catalysts for heavy-duty applications decreased a number of years ago. Most heavy-duty engine manufacturers realized that the system complexity as well as the durability of such a system does not allow large volume production without significant risk. The current consensus of the heavy-duty community is that for 2010 the SCR system will be the prime path to meet the 0.2 g/bHPhr NOx emission standard, although this is subject to adequate infrastructure investment and progress. As a low volume manufacturer, in order to comply with the 2007 heavy-duty phase-in emission standards, General Engine Products (a subsidiary of AM General LLC) integrated a NOx adsorber system on the Optimizer 6500 engine. This engine features split combustion chamber design, rotary fuel injection pump and operates with EGR.

The problem of determining a least squares estimate for radius and eccentricity of a circular part on a shaft, such as a bearing journal, is formulated. The resulting equations are more complex than the usual linear system of equations associated with least squares applications, but the problem is readily amenable to computer solution. The presentation closes with the results for two numerical test cases.

Facial recognition software (FRS) is a form of biometric security that detects a face, analyzes it, converts it to data, and then matches it with images in a database. This technology is currently being used in vehicles for safety and convenience features, such as detecting driver fatigue, ensuring ride share drivers are wearing a face covering, or unlocking the vehicle. Public transportation hubs can also use FRS to identify missing persons, intercept domestic terrorism, deter theft, and achieve other security initiatives. However, biometric data is sensitive and there are numerous remaining questions about how to implement and regulate FRS in a way that maximizes its safety and security potential while simultaneously ensuring individual’s right to privacy, data security, and technology-based equality.

The objective for this study was to revisit some of the known factors that affect legibility including font characteristics, as well as, contrast polarity, luminance contrast, and color contrast under high ambient conditions as specified in SAE J1757. The study focused on older drivers due to their increased visual needs and limitations. The study was conducted in 2 phases: 1) a study of font characteristics; character height, character width, and stroke width using a central composite design. Subjects read a group of letters and numerals displayed on a laptop display using occlusion goggles. The reading time (Total Shutter Open Time or TSOT), reading errors, and a subjective Readability Rating (using a 4 point scale "Very Easy," "Easy," "Difficult," "Very Difficult") were recorded. Licensed drivers in three age groups, 25 to 44 yrs, 45 to 59 yrs, and 61 to 91 yrs participated. The response surfaces were generated and compared to the character sizes recommended in ISO 15008.

The lead battery industry's proactive approach to working with state and federal regulators on environmental regulatory and legislative issues has proven to be a successful tool in producing a high recycling rate for lead-acid batteries. The reverse distribution system set up by the battery industry to collect and recycle lead-acid batteries alleviates the concerns raised by governmental agencies and environmental groups over how the batteries are handled. Not only does the industry benefit from better public relations as a result of their commitment to ensure a high recycling rate, it also provides a reliable source of recyclable materials necessary to operate battery recycling facilities.

This paper outlines Pi Technology's approach to testing high-reliability automotive software. Based on data collected during an engine controller development, it discusses the value of different types of testing at various stages of the design process and when errors are found. The team structure used for embedded systems is discussed to provide the context in which software development occurs.

The ISO 26262 series of standards for vehicle functional safety codify requirements to avoid unreasonable risk from the failure of electrical or electronic (E/E) systems. E/E failures may cause malfunctioning behavior that manifest as vehicle-level hazardous events. The ISO 26262 second edition includes commercial trucking, which employs significant variation from the passenger car development cycle. The highly distributed nature of E/E system development and integration in commercial trucks complicates forging unified safety concepts. For instance, the Fault Tolerant Time Interval (FTTI) quantifies the minimum time span from the occurrence of a fault to the possible occurrence of a hazardous event. Often, the subjectivity involved in defining unreasonable risk and hazardous event onset frustrates consensus among stakeholders.