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The laboratory testing of large structural components has now become a very important phase of the research and development program at Caterpillar Tractor Co. This paper discusses the need and reasons for laboratory testing, along with specific advantages that this type of testing offers. The history of Caterpillar’s structural testing program is reviewed and several tests are briefly discussed. Finally, the new concrete bedplate located at their Technical Center is thoroughly described and compared with similar bedplates in existence elsewhere.

The performance of simple tool shapes in terms of draft with speed of operation was evaluated in the soil bin facility of the Department of Agricultural and Bioresource Engineering, University of Saskatchewan. A hydraulic driven monorail system was developed, which was capable of speeds up to 10 m/s. The results showed that the disturbed soil remained close to the cutting path, and the elliptical shape exhibited the lowest draft increment with speed.

The U.S. Bureau of Mines is conducting laboratory evaluations of the effectiveness of oxidation catalytic converters (OCC's) for application on diesel engines used in underground mines. The composition of the exhaust emitted from a diesel engine depends critically upon the fuel-to-air ratio (F/A). The F/A changes significantly with altitude, requiring regulatory derating of engines used at altitudes above 0.30 km (1000 ft). It is important to evaluate exhaust control devices for application on mining vehicles at various altitudes because mines are located at a wide range of elevations. The objective of this work is to determine the characteristics and performance of an OCC at various altitudes as well as investigate an altitude simulation technique used in a laboratory setting.

A first retrofit conversion of a Cummins NTC335 engine to spark ignition was carried out in New Zealand in 1984. The conversion used widely available technology for stoichiometric control of natural gas fuel - air mixtures. Experience from the on-road application in a 40,000 kg GVW truck contributed much to the later development of a 400 hp gas-fuelled variant of the same engine family, using lean mixture carburettion control. A second engine entered service in a logging application in February 1989. The following paper summarises results arising from laboratory testing of the second engine, and from in-field monitoring. Also presented are preliminary results from testing of a third generation engine, using timed multi-point injection of gas fuel.

Body-over-Frame is the primary type of construction used in SUVs, pick-ups, and other commercial vehicles in India. In this type of construction, the body, engine, suspensions etc. are mounted on the ladder frame. Since the frame acts as the skeleton of the vehicle, optimal design of frame at the concept stage of the vehicle program is critical for meeting all structural performance targets. Frontloading of these targets aids in architecture development and reduces future design modifications. The natural frequency response from the frame directly affects the NVH performance of the vehicle. This paper focuses on frontloading the natural frequency targets by performing concept-level simulations on the ladder frame even before creation of 3D concept data. A parametric beam model is created based on the reference vehicles. The beam model has been validated with correlation of more than 85% compared with CAE and physical testing outputs of existing vehicles.

Laminar Sealing Rings as grease seals and dirt excluders for rotating shafts and housings have been used in Europe for more than 30 years. They form a highly efficient labyrinth seal that is virtually non-contacting, and therefore produce hardly any friction, heat or wear; their nearly unlimited temperature and speed-range, high reliability, minimum space requirements and insensitivity towards end-play and eccentricities allow the use of Laminar Sealing Rings for a wide variety of applications. This paper covers the use of Laminar Sealing Rings as grease seals and dirtexcluders/protectors of elastomeric shaft seals for rotating shafts and housings and intends to give the designer an introduction to this sealing element.

The use of high performance Laminated Elastomeric Bearings is offered as an alternative to conventional roller element or metallic contact bushings for continuous load support and motion control. The discussion includes the design considerations necessary for proper application, as well as the Engineering, Manufacturing, and Quality Assurance inherent within the technology today. Major advantages include no required lubrication, significantly different spring rates between elastomer compression and shear planes, positive sealing, and reduced maintenance costs.

Tractors are generally provided with step and grab rail systems to facilitate driver entrance and exit from the cab. However, many of these systems are not designed based on human factors engineering principles, particularly anthropometry and thus are not always used. Some examples include steps or rails that are too high for a cross-section of the population to reach or steps that are difficult to see as the occupant descends from the cab. Trailers frequently do not have any “designed steps/grab rails” to aid the driver or material handler in safely climbing up or down from the rear of the unit. As a result, squat jumping from the trailer floor down to the ground is a common method of exit from commercial trailers. Injuries resulting from exiting commercial vehicles could represent a substantial cost to businesses operating these equipment.

The lateral stability of vehicle combinations can be severely reduced at high speed manoeuvres. It is desirable to avoid that combinations with poor performance in this respect are used. Regulations involving computer simulation control have been proposed in Sweden. The method can be characterized as a computer simulated double lane change test. The towing vehicle is guided through the manoeuvre by means of an inverse steering procedure. The safety criteria concern lateral deviations, side slip angle maxima, overturning risk and the relation between risk factors of truck and trailer. The paper reports a study concerning truck and full trailer combinations with geometric design parameters varied within the limits set by length and axle load regulations in Sweden and GFR. The results show that most of the combinations are acceptable. However, two axle trailers with short platform and three axle trailers with long bogie failed under certain conditions.

Vehicle accidents caused by driver inattention and drowsiness represent a problem on both European and American roads. In-vehicle technical innovations, such as lane departure warning systems, are seen as a way to reduce the personal and material costs related to such accidents. Daimler-Benz and Odetics have developed and tested a lane departure warning system, based on image processing lane marking detection. A Time-to-Line-Crossing criterion was used to generate an acoustic warning in the form of a “rumble strip noise.” The latter was found to effect the fastest and most appropriate driver reaction. The technology developed for European roads and test results are discussed, as well as how these require adaptation for application to the US road system. A plea is made for enhancement of the technology and standardization of lane markings on American roads.

Lane marking detection plays a crucial role in Autonomous Driving Systems or Advanced Driving Assistance System. Vision based lane marking detection technology has been well discussed and put into practical application. LiDAR is more stable for challenging environment compared to cameras, and with the development of LiDAR technology, price and lifetime are no longer an issue. We propose a lane marking detection algorithm based on solid-state LiDARs. First a series of data pre-processing operations were done for the solid-state LiDARs with small field of view, and the needed ground points are extracted by the RANSAC method. Then, based on the OTSU method, we propose an approach for extracting lane marking points using intensity information.

A large percentage of commercial vehicles transport freight on our interstate highway system. These vehicles spend the vast majority of their duty cycle at high speed maintaining a lane. As steering is integrated into ADAS, objective performance measures of this most common mode of commercial vehicle operation will be required. Unfortunately in the past this predominant portion of the commercial vehicle duty cycle was overlooked in evaluating vehicle handling. This lanekeeping mode of operation is also an important, although less significant portion of the light vehicle duty cycle. Historically on-center handling was compromised to achieve acceptable low speed efforts. With the advent of advanced active steering systems, this compromise can be relaxed. Objective measures of lanekeeping are developed and performance of various advanced steering systems is quantified in this important operating mode.

Temporary facilities for construction projects become an important factor in the bidding stage of a large construction project and should be included in technological drawings and procedures later on. Guidelines for design selection and layout of the following temporary facilities categories are presented: field offices, field laboratory, lodging facilities, road and platforms, water-heating, electricity requirements, repair and maintenance field shops, plant site including temporary construction concepts, cost estimating criteria, planning on scheduling of temporary facilities requirements with the main project(s) schedule.

In partially premixed combustion engines high octane number fuels are injected into the cylinder during the late part of the compression cycle, giving the fuel and oxidizer enough time to mix into a desirable stratified mixture. If ignited by auto-ignition such a gas composition can react in a combustion mode dominated by ignition wave propagation. 3D-CFD modeling of such a combustion mode is challenging as the rate of fuel consumption can be dependent on both mixing history and turbulence acting on the reaction wave. This paper presents a large eddy simulation (LES) study of the effects of stratification in scalar concentration (enthalpy and reactant mass fraction) due to large scale turbulence on the propagation of reaction waves in PPC combustion engines. The studied case is a closed cycle simulation of a single cylinder of a Scania D13 engine running PRF81 (81% iso-octane and 19% n-heptane).

Embedded software development has been dramatically improved with model based design and auto code generation tools. However, the development process of complicated embedded control systems still faces great challenges. Modern embedded control becomes so complicated due to sophistical control hardware and control optimization driven by competitive pressure and regulations. For example, engine embedded control development has to consider global emissions and On Board Diagnostics (OBD) regulations besides various vehicle platforms for the global market. This paper presents several design aspects for complex embedded control software architecture including component based design, component management, and software validation. The paper discusses several software architecture design ideas and analyzes their design benefits and disadvantages. Finally, the paper proposes a software architecture design and provides a design example.

School bus travel is one of the safest forms of transportation on the road today. The passenger fatality rate in school buses is 0.2 fatalities per million vehicle miles traveled (VMT) as compared to 1.5 per million VMT for passenger cars and 1.3 per million VMT for light trucks. Each year on average, nine school bus passengers are fatally injured in school bus crashes while sixteen school-age pedestrians are fatally injured by the school bus. Although much has been done to improve the safety of school buses over the years, more research may reflect new ways to better protect school bus passengers. The National Transportation Safety Board concluded in 1999 that current compartmentalization is incomplete in large school buses in that it does not protect passengers during lateral impacts. In order to better understand severe lateral impacts to school buses and the resulting passenger motion and injuries, the stiffness of the side of the school bus needed to be determined.

Glare from the headlights of following vehicles which is reflected in rearview mirrors can be a significant problem. Glare can cause driver discomfort, it can diminish the driver's ability to see, and it can cause driver fatigue, particularly during prolonged night-time driving common for many professional drivers. Conventional rearview mirrors, such as silvered and chromed mirrors, offer only one reflectivity level. Variable reflectance mirrors, such as those utilizing electrochromic and liquid crystal technology, are capable of multiple reflectance levels. With variable reflectance, the driver can select a high reflectivity level during daytime driving or when reversing into loading docks, and can select a reduced dimmer reflectance level when driving during glaring conditions. This paper briefly reviews the principal technologies available for variable reflectance mirrors and outlines their performance as glare-reducing mirrors.

With a well-controlled laser melt injection (LMI) process, for the first time the feasibility is demonstrated to produce SiC particles (SiCp) reinforced Ti6Al4V functionally graded materials (FGMs). SiCp are injected just behind the laser beam into the extended part of the laser melt pool that is formed at relatively high beam scanning velocities. The process allows for the minimization of the decomposition reaction between SiCp and Ti6Al4V melt, and also leads to FGMs of SiCp/Ti6Al4V instead of a homogeneous composite layer on Ti6Al4V substrates. An injection model is designed based on the temperature/viscosity field of the laser pool for a deeper understanding the mechanism of formation of the FGMs with LMI. The model is based on finite element calculations of the temperature field in the melt pool, physical considerations of the LMI process and it is supported by experimental observations.

Propelled by the need for improved agricultural and construction productivity, industry has seen continued growth in the use of laser-based systems for blade control on earthmoving equipment. This growth has been supported by advances in micro-electronic and laser technology resulting in systems which offer increased performance and lower costs. To fully utilize the capabilities and benefits of this control technology, the hydraulic, electrical and mounting interfaces between the machine and laser control system need to be more compatible. The use of closed center hydraulics and allocation of adequate cab space for controls are two areas of machine design that could simplify installation, improve system performance and reduce cost.

Laser glazing of steel is being investigated as a means of improving its tribological properties for railroad and other applications. The microstructure of the surface layer on 1080 steel formed by the process was characterized by optical and transmission electron microscopy (TEM) and microhardness measurements. The microhardness increases were consistent with self-quenching of the 1080 steel, followed by tempering of adjacent areas. TEM revealed a very fine (5-10 nm) grain size. Friction and wear tests were conducted on glazed and unglazed materials with a pin-on-disc test rig. Laser glazing reduced both friction and wear during dry tests. The improved friction and wear performance is attributed to the microstructural changes of the near-surface region by laser glazing.