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This study analyzes the power consumption of a specific Planetary Exploration Vehicle (PEV) subsystem known as Flexible-Wheel (FW) suspension, more specifically the interaction between a FW and the deformable terrain upon which it traverses. To achieve this a systematic and analytical calculation procedure has been developed, which culminates in the definition of three dimensionless properties to capture the FW-soil interaction. Aimed towards the design engineer participating in concept evaluation, and the control engineer conducting initial analyses, this study has found that the resistance coefficient for the interaction between a FW and the deformable terrain can, in general, be several orders of magnitude higher than the rolling resistance of a pneumatic tire operating upon rigid terrain.

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 impact of Reynolds number on the aerodynamics and operational performance of commercial vehicles is discussed. All supporting data has been obtained from published experimental and computational studies for complete vehicles and vehicle components. A review of Reynolds number effects on boundary layer state, unsteady and steady flow, time dependent wake structure, interacting shear layer and separated flows is presented. Reynolds number modeling and simulation criteria that impact aerodynamic characteristics and performance of a commercial vehicle are shown. The concepts of dimensional analysis and flow similarity are employed to show that aerodynamics of commercial ground vehicles is only dependent on Reynolds number. The terminology of Roshko is adopted for discussing the variation in drag with Reynolds number in which the subcritical, transitional and transcritical flow regimes are defined for commercial vehicles.

A challenge in structural design is the inability to quickly assess how a change in use can affect the structural performance of the system. This is particularly important in the bus industry where there is often multiple variations of one base product type for many customers. Thus for a single design there can be frequent changes to mission profiles or customer constraints, which must be considered within short time periods before production commences for a particular customer. This can often limit full understanding of the structural performance, key structural features or critical failure modes, ultimately limiting the potential for producing buses with minimum structural mass. The proposed method in this paper aims to develop a design tool capable of rapidly informing structural design engineers with respect to the structural limitations of various vehicle components using performance envelopes.

This SAE Standard applies to the usage of tires of the same nominal size and tread type, but with different outside diameter for articulated front-end loaders. Articulated four-wheel-drive front-end loader performance and component life can be affected by excessive differences in the tire outside circumference and/or diameter. The purpose is to provide specific guidelines for the usage of tires with different outside circumference and/or diameter on articulated front-end loaders.

This SAE Standard applies to the usage of tires of the same nominal size and tread type, but with different outside diameter for articulated front-end loaders. Articulated four-wheel-drive front-end loader performance and component life can be affected by excessive differences in the tire outside circumference and/or diameter. The purpose is to provide specific guidelines for the usage of tires with different outside circumference and/or diameter on articulated front-end loaders.

Provision of service information in various languages has been a must in the automotive industry. However, in the commercial vehicle industry, it is unclear how manufacturers are managing this daunting task. California Air Resource Board (CARB) 2010 regulations are awakening the commercial vehicle service information managers who are responsible for providing this information according to SAE J2403 terminology. Now is the time to mimic the automotive industry by collaborating on terminology, and in the meantime, begin discussion on how we all manage multiple languages.

How will a mechanic troubleshoot the heavy duty vehicle of the future? Will he or she have to be both retriever and integrator of data collected from multiple black boxes on the vehicle? How many tools will it take? Is there a definition of a vehicle system “diagnostic environment” that needs to be developed in order to create a solution to this problem? This paper will attempt to create the system focus for vehicle diagnostics that is required if this industry is to successfully produce the integrated electronic vehicle of the future. Both the on-board and off-board requirements of the diagnostic environment will be examined.

Data link interfaces have become a requirement for the heavy duty vehicle industry because of the need to share information between individual subsystems. Therefore, it is important for the industry to be familiar with the existing heavy duty vehicle serial data communications standards. SAE has addressed the need to share information between individual subsystems and this paper presents the serial data communications adopted in SAE Recommended Practices J1708, J1587 and J1922 as well as J1939 which is currently under development by the Truck and Bus Control and Communications Network Subcommittee. For a vehicle of the early to mid-1990s, the J1708, J1587 and J1922 documents provide the standards to accommodate general information sharing, detailed diagnostic definition and early powertrain controls integration. The J1939 document being developed will define a network that encompasses all the requirements satisfied by J1708, J1587 and J1922 and any new requirements that arise.

In the automobile and earthmoving market place, consumer pressure is creating a demand for more environmentally considerate products. One aspect of this definition is biodegradability. In the forestry and farming industries where lubricant losses and spillages are recognised as a significant potential hazard, the use of these products is now widespread and in terms of environmental protection, the benefits are multiple. This paper discusses technical developments based on vegetable oils, including an assessment of additive requirements to meet performance needs. It also reviews necessary work to define other aspects of performance.

This paper discusses various aspects of: biodegradable hydraulic lubricants; the type of bio-oils (biodegradable) available; the approved test method of bio-oils; a label called Blue Angel used for the identification of environment friendly products; bio-oil applications; practical field test experience and economic impact. The paper provides a general view of the current situation in Central Europe. Practical experience with environment-friendly oil and grease has been known for over 4,000 years. When the pyramids were built, animal and vegetable oil and grease was used to lubricate transport sledges. At that time, it was not an environmental protection consideration. Today it is our challenge to protect people, plants and animals. Who would have thought that environmental protection would become such an important and inevitable issue? Five or ten years ago words like biodegradable, environment-friendly, environment-compatible were definitions hardly known to most people.

Since defining quality so it will be accepted from company to company is a difficult task. This paper will discuss definitions of quality and how metrology can assist a company in defining its' quality. The title; Metrology:A Definition of Quality implies an explanation of how metrologists thinking has become important to companies committed to quality. This paper discusses the advantages quality programs derive from having metrology heavily involved in their processes and procedures. This paper also talks about the changing role of metrologists from strictly calibrating of the test equipment to applying process metrology in order to ensure the overall quality of the products.

This procedure applies to hydraulic fluid power valves as applied to self-propelled work machines as referenced in SAE J1116.

This standard provides the names of major components of dozers which include a blade and all associated structural elements, normally mounted in front of a self-propelled machine for scraping and pushing materials through forward motion of the machine. It also includes dimensional specification definitions applicable to dozers. This standard is applicable to dozers which are commonly used on crawler and wheel tractors as defined in SAE J1057.

This SAE Recommended Practice defines the boundary line for establishing dimensional compatibility between air disc brake calipers and 22.5 x 8.25 inch disc wheels, including bent valve stems on steel wheels and manufacturer recommended valve stems on aluminum wheels. The line establishes the minimum wheel with valve stem envelope to allow interchangeability. The line does not accommodate customer-specific wheels (such as OEM-specific stylized wheels) or customer-specific brakes. This document addresses dimensional characteristics only and makes no reference to the performance, operational dynamic deflections or heat dissipation of the system. It is up to the system integrator to ensure sufficient clearance exists between the caliper, wheel and valve stem to provide safe operating conditions. Mounting systems as noted are referenced in SAE J694.

The purpose of this SAE Recommended Practice is to describe the terms yield strength and yield point. Included are definitions for both terms and recommendations for their use and application.