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Automotive industry is a major contributor to global carbon dioxide (CO2) emissions and waste generation. Not only do vehicles produce emissions during usage, but they also generate emissions during production phase and end of life disposal. There is an urgent need to address sustainability and circularity issues in this sector. This paper explores how circularity and CO2 reduction principles can be applied to design and production of automotive parts, with the aim of reducing the environmental impact of these components throughout their life cycle. Also, this paper highlights the impact of design principles on End-of-Life Management of vehicles. As Design decisions of Component impacts up to 80% of emissions [1], it is important to focus on this phase for major contribution in reduction of emissions.

The extensive use of rotative machines in the diverse branches of the modern world has made the rising undesirable mechanical and acoustic vibration levels to be a problem of special importance for the machines normal operation as for the communities that are each time more affected by the problem. It makes the study of vibration and acoustic phenomena also to be even more important and the applications of its concepts more sophisticated. Several are the concepts used for decreasing vibration levels, like common dampers, hydraulic dampers, active dampers, natural frequencies changes and others. The choice of use of one or another depends greatly on the engineering possibilities (weight, energy, physical space, other components functional interference, vibration levels, etc.) as well as the cost of implementation of each one.

As a typical parameter of the road-vehicle interface, the road friction potential acts an important factor that governs the vehicle motion states under certain maneuvering input, which makes the prior knowledge of maximum road friction capacity crucial to the vehicle stability control systems. Since the direct measure of the road friction potential is expensive for vehicle active safety system, the evaluation of this variable by cost effective method is becoming a hot issue all these years. A ‘wheel slip based’ maximum road friction coefficient estimation method based on a modified Dugoff tire model for distributed drive electric vehicles is proposed in this paper. It aims to evaluate the road friction potential with vehicle and wheel dynamics analyzing by using standard sensors equipped on production vehicle, and fully take the advantage of distributed EV that the wheel drive torque and rolling speed can be obtained accurately.

SPARE TIRE elimination is a problem that has defied tire engineers for years. Because the space it occupies is wanted for other purposes, increased efforts are being applied to the search for a solution. This paper describes one approach — the dual compartment tire. This is made up of two tires, one inside the other, both of which are inflated at all tiines. If the outer tire is punctured, the inner tire supports the car until it reaches a service station. According to the author, tests indicate that this solution holds promise of eliminating the spare — if the cost can be lowered.*

Linked front and rear braking systems are difficult to implement properly on motorcycles due to the large changes in wheel loading under braking. At the braking limit, there is little to no load on the rear wheel and any brake torque could lock it, making the vehicle laterally unstable. Therefore, most motorcycles have independent controls for the front and rear brakes, requiring the rider to balance the brake force distribution. Electric motorcycles have the ability to utilize the drive motor to apply braking torque at the rear wheel. In this paper a control technique has been developed to link rear wheel braking torque to the front brake lever without risking rear tire lock. Thereby, it is also possible to recapture the energy from rear wheel braking. The control strategy has been tested on a transient pitch model, with rotating wheels and tire model data.

In spite of environmental issues related to cadmium and its electroplating process, electroplated cadmium is still extensively used in the aerospace and defense sectors. This trend is likely to continue especially for high strength steels because cadmium provides the best known corrosion and embrittlement protection for this application. Consequently, the environmental concerns related to the cadmium electroplating have been addressed using an alternative Zero-waste Physical Vapor Deposition (Z-PVD). This method does not use liquids, it recycles cadmium in situ, and is free of hydrogen embrittlement. The Z-PVD process is now in commercial production for the aerospace fasteners. The quality of the coatings has been at least equal to that of the electroplated cadmium.

OBD system requirements were first developed by the California Air Resources Board, the U.S. Environmental Protection Agency, and the European Commission. New OBD requirements should be as consistent as possible with existing requirements to maximize reliability and to minimize system complexity, proliferation of configurations, and consumer cost. New OBD requirements from around the world are briefly reviewed and most are consistent with the original U.S. and European requirements. Worldwide OBD requirements are being further harmonized under the United Nations, Economic Commission for Europe, World Forum for Harmonization of Vehicle Regulations (WP29). Presenter David H. Ferris, General Motors Company

Demands of the earthmoving industry for indepth tire knowledge and performance capabilities has placed increased responsibility on the tire manufacturer for establishing operating limits. The challenge of meeting these demands has resulted in an increasing amount of controlled tire testing conducted under simulated field conditions. One of the areas of required information has been for the establishment of Dozer and Loader tire capabilities when operating in Load and Carry service. Since tire heat becomes a major potential problem in Load and Carry service, a method was required to determine the performance capabilities of Dozer and Loader tires so that optimum tire life could be achieved. This paper covers the need for tire limits; basic Dozer and Loader tire design requirements; the method established for determining tire capabilities in Load and Carry service, and finally the factors differentiating this rating system from the TMPH system which is used for transport type vehicles.

A review of passenger tire construction and the engineering properties required of belt ply materials is presented. Comments are made on the areas of wire cord construction that must be investigated in order for the cost of wire cord to be reduced. Included are elastic modulus, dimensional stability, adhesion to rubber, environmental sensitivity, column strength, tensile strength, bending modulus, and endurance limit. The joint responsibilities of the equipment manufacturers, wire cord manufacturers, and tire companies are discussed.

A review of tire testing in the winter environment is presented from the viewpoint of an independent testing laboratory. The independent tester, by necessity, must satisfy the particular requirements of individual customers. A description of the drive traction truck which was designed to meet these individual client requirements is presented. Also, a comparison of results obtained by the various techniques of analysis is included.

The performance of winter tires is characterized by snow traction and ice skid tests. Winter tire testing is reviewed in regards to the hardware used, design of a test program, site selection, and data analysis. The description of the hardware includes a review of a new traction measurement system. The system incorporates a traction truck with an instrumented axle at a driven wheel position interfaced with a mini-computer which controls the test, stores the measurements, and performs the data analysis.

Winter testing of cars and tires for consumer comparisons is not an easy task to begin with; this is further complicated by the fact that reliable methods for evaluating performance and access to good testing conditions are unavailable to most magazines. The testing group at Tekniikan Maailma Magazine, Finland, has been fortunate to have both the right conditions as well as reasonable resources to develop methods of testing to the extent that they provide sufficiently reliable data to assess vehicle and tire performance in winter conditions. Before any final evaluations are published in the magazine, the weighing of different factors, i.e. the amount of importance placed on different performance characteristics, is carefully considered. In order to achieve a meaningful ranking of these products in relation to different characteristics, constant reference runs, statistical research methods, and highly skillful test drivers are employed.

To investigate the feasibility of various test procedures to determine aerodynamic performance for the Phase 2 Greenhouse Gas (GHG) Regulations for Heavy-Duty Vehicles in the United States, the US Environmental Protection Agency commissioned, through Southwest Research Institute, constant-speed torque tests of several heavy-duty tractors matched to a conventional 53-foot dry-van trailer. Torque was measured at the transmission output shaft and, for most tests, also on each of the drive wheels. Air speed was measured onboard the vehicle, and wind conditions were measured using a weather station placed along the road side. Tests were performed on a rural road in Texas. Measuring wind-averaged drag from on-road tests has historically been a challenge. By collecting data in various wind conditions at multiple speeds over multiple days, a regression-based method was developed to estimate wind-averaged drag with a low precision error for multiple tractor-trailer combinations.

The wide base light truck tire is a new low profile, wide rim tire concept, which significantly improves vehicle performance. The wide base tire also simplifies and standardizes tire and rim usage, making obsolete the variety of tire sizes, types, and rim styles previously available.

This SAE Recommended Practice establishes uniform engineering nomenclature for wide base disc wheels and demountable rims. This nomenclature and accompanying figures are intended to define fundamental wide base disc wheel and demountable rim terms. The dimensions given are those necessary to maintain serviceability and interchangeability of the wide base disc wheels and demountable rims with standard hardware. Valve clearances have not been included in this document.

This SAE Recomended Practice establishes uniform engineering nomenclature for wide base disc wheels and demountable rims. This nomenclature and accompanying figures are intended to define fundamental wide base disc wheels and demountable rim terms. The dimensions given are those necessary to maintain serviceability and interchangeability of the wide base disc wheels and demountable rims with standard hardware.

This SAE Recommended Practice establishes uniform engineering nomenclature for wide base disc wheels and demountable rims. This nomenclature and accompanying figures are intended to define fundamental wide base disc wheels and demountable rim terms. The dimensions given are those necessary to maintain serviceability and interchangeability of the wide base disc wheels and demountable rims with standard hardware. Valve clearances have not been included in this document.

This paper discusses the several reasons why vehicles do not achieve the EPA MPG values in service, and makes a numerical estimate of the magnitude of the individual effects. In addition, methods for adjusting EPA MPG values to estimate road fuel economy performance are presented and discussed.

TIRE matching is not a simple matter, says Mr. Place, for a good program of matching on one operation may not give as good results, relatively, on another. For this reason, he asserts that it is impossible to make one blanket recommendation that will give the best overall results on all fleet operations. Thus, he confines himself to describing what takes place during the use of dual tires, and discusses certain service expedients that operators may try under close observation.