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The wheel motor is a combination of hydro-motor and planetary transmission. Industrial, agricultural, construction and various types of public utility vehicles, which due to their design cannot use axle drives, make increasing use of the individual wheel drive. Speed, torque transmission, wheel bearings, valves for hydraulic operation and hydraulic engagement/disengagement are some of the requirements for wheel motor drives.

AID for the fleet operator is contained in this paper, which presents basic information to help him get the best from his fuel, whether he uses gasoline or diesel fuel, from his lubricating oil, whether he uses the regular or heavy duty, and from his gear lubricants.

The design and development of an encoding altimeter incorporating a new method of display and an improved coding scheme for the transmission of altitude information to air traffic controllers is presented.

In view of the increasing varieties of equipment operated by engine power take-offs, it is desirable to have some method of estimating power requirements before purchasing a truck. This paper offers a yardstick by which owners will be able to approximate transmission capability of driving auxiliary equipment. The method is based on the pitch line velocity of the driving gear in the transmission, and each step is fully explained and illustrated.

In the past decade, the space shuttle has been the key factor for the United States manned space exploration. In fact the space shuttle is the only means in which the United States government can send humans into space. However, the space shuttle's life-expectancy is due to expire around the year 2005. In preparation for the end of the space shuttle era, we, as a country, must decide what type of future space vehicle is appropriate to accomplish our future national goals in space. There are many public policy alternatives to the question: ‘What will replace the space shuttle?’ First, the United States could try a conservative approach to space exploration by developing and using an unmanned vehicle. Second, the government could opt for utility by developing a mixed fleet of launch vehicles. Third, the United States could try to modify and update the current space shuttles with new technology.

UNJUST legislation in the middle of the 19th Century retarded the introduction of road locomotion. The Motor Carrier Act, 1935, calls for extreme regulation, patterned after railroad control. The many differences between the two services prevent like treatment without strangling the virtues and economies of motor transportation. The difficulty of attempting to regulate it is due to the fact that most “fleets” consist of one truck which is owner-operated and only 9 per cent of all trucks are of the For-Hire type. The present predicament of the railroads is due chiefly to general conditions brought about by the depression, the result of over-regulation, and in not keeping in step with the advancement of other industries. The passenger automobile accounts for some loss of revenue, but its use is taken for granted. It therefore seems strange that the other forms of rubber-tired vehicle are not accepted in the march of progress.

THIS paper is a non-technical review of an up-to-date survey of the lines of tires needed in all types and classes of fleet operation. To understand better how to get the best results from their operations, operators must know the proper type of tire to use. The author first describes and catalogs the principle forms of tire failures, then reviews the characteristics of the fundamental lines of tires available at the present time. Next, an attempt is made to classify the different types of fleet operation so that definite recommendations can be made as to the most appropriate tire equipment for these vehicles. The types of tire trouble most commonly encountered in each group are brought out with suggestions on how to avoid them. This part is followed by a section giving advice on the care of tires. The paper concludes with a brief survey of worthwhile facts about repairs and retreading. An appendix contains the load-inflation tables which are most widely used.

Electronic data processing has been used as a management tool in vehicle replacement, inventory control, and vehicle maintenance in a large fleet. It also shows promise in vehicle maintenance scheduling. Data processing can point out problem vehicles, and predict maintenance cost in the future so vehicles can be replaced at the most economical cost.

This paper shows how the quantity demanded, viewed as an independent variable, interacts with customer values, producer costs and constraints. Failure to analyze Demand as Independent Variable (pronounced “Dave”) increases the chances that new programs will not launch, or once started, will fail. All producers in all markets face demand curves that describe their customers' reaction to price changes. Aggregate market demand curves show how buyers react to price changes within broad product sets, while product demand curves show buyer responses to a specific item. Demand curves relate quantities sold relative to their prices. In several military, transit and fleet cases, minimum quantity requirements form upper price boundaries along demand curves. Allowing prices to go so high that buying authorities cannot acquire the required numbers of units likely means that there may not be sufficient resources to form systems that can accomplish the buyers' goals.

Facing global climate change and the oncoming shortage of fossil resources, it is necessary to reduce fossil energy consumption. There is a strong need for action concerning road traffic as a main originator of greenhouse gas emissions by use of fossil energy. For a strong mitigation effect, the technological improvement of today’s petrol and diesel engines has to be accompanied by the promotion of alternative vehicles, still being sparsely represented in most car fleets. The spread of one or more new drive-train technologies throughout the transportation sector represents an innovation diffusion process, which is needed in order to achieve long-term climate and energy policy goals. By applying our recently developed model for the market penetration of competing alternative drive-train technologies, this work contributes to the understanding of main processes influencing the diffusion rate.

The physical and chemical properties of a mineral-based (Fluid-M) and a partial-synthetic-based (Fluid-PS) automatic transmission fluid were compared by the analyses of Gel Permeation Chromatography (GPC), Thermogravimetry (TG), Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), Gas Chromatography (GC), viscometry, thermo-oxidative stability, torque response curve shape and metal-to-metal wear preventive characteristics. The effects of various properties of Fluid-M and Fluid-PS on wet friction material performance were investigated from the viewpoints of compressibility, durability, tensile strength, surface interactions and friction-pressure-speed-temperature characteristics. Friction material specifications for partial-synthetic fluid applications will be different from those for mineral-based fluid applications. GPC showed that Fluid-PS has a higher concentration and a lower molecular weight of VI Improver than Fluid-M.

Lubricant and lubricant additive interactions with clutch linings and lining materials were measured at elevated temperatures. Swelling, weight, and compressibility changes were related to material chemistry and endurance test results. Interactions of specific clutch lining ingredient-lubricant additive combinations were identified to help explain why different clutch linings perform better in some lubricants than in others.

Formulas are derived to show that moving elements of a drive train can contribute to the energy seen by the clutch plates. Oscillograph traces, sample calculations and photographs of failed plates show actual energy at failure of test plates. The formula is presented for calculating instantaneous energy when coefficient of friction, apply pressure and slip speed are known or can be estimated.

Wet clutches drag loss simulation is essentially linked to the clutch friction surface patterns in addition to the main geometry and conditions of the interface (relative speed, separation, inner and outer radius, viscosity and boundary pressures). The clutch patterns promote cooling flow and micro-hydrodynamic effects to aid clutch separation but greatly complicate the simulation of drag loss during separation. These drag losses are important in understanding the system losses as well as finding the most effective clutch cooling strategy. Typical clutch models either only consider simple patterns, such as radial grooves, or require significant simulation efforts to evaluate. Additionally, many simple models require calibration to measurement of the actual clutch they try to model before they provide a useful model.

In the competitive market of the car industry today, companies need to continuously strive to optimize the performance, price and environmental properties of their products in order to survive. Wet clutches, as parts of transmission components of passenger cars are no exception. An understanding of how the wet clutch system functions and fails is necessary to optimize price and service life. The friction characteristics of the wet clutch system are determined by lubricant-surface interactions in the contact between the friction discs. Wet clutch failure can often be associated with the deterioration of friction characteristics which eventually leads to stick-slip or shudder. Consequently, knowledge of why and of how friction characteristics change over time is of the outermost significance to enable the understanding and prediction of wet clutch performance. As the lubricant is an essential component of the wet clutch system, lubricant ageing is a factor of importance.

This paper presents a Well-to-Wheels (WTW) analysis of equivalent carbon dioxide (CO2eq) emissions in different scenarios of replacement of a conventional taxi fleet by electric vehicles. Two battery electric vehicles and one hybrid electric vehicle were used in the comparison with the conventional vehicle fleet. A numeric model was developed to evaluate CO2eq emissions in the fuel production, electricity supply, and vehicle operation phases. Gasoline and sugarcane ethanol were considered as fuels for the conventional and hybrid electric vehicles. Six scenarios of conventional vehicles replacement by electric vehicles in the taxi fleet were evaluated. The results showed that the replacement of nearly 13% of the current taxi fleet of a major city by the three electric vehicle models considered in the analysis could reduce CO2eq emissions by about 6%. If the entire fleet was replaced in a 5 years period, CO2eq emission could reach a reduction up to 82%.

The objective of this study is to determine the energy use and Greenhouse Gas (GHG) emissions involved in adopting various electrified vehicle technologies over the next decade in Canada and the United States. The vehicle architectures selected for this work stem from those in the EcoCAR competitions. Each architecture was simulated using Argonne National Laboratory's (ANL) Powertrain System Analysis Toolkit (PSAT) software to determine the energy consumption and petroleum use. Natural Resources Canada's GHGenius model and ANL's GREET model were employed to determine the upstream emissions resulting from each region's power generation mix. Results from each powertrain and fuel combination were analyzed in order to understand the repercussions of introducing these vehicle technologies over the next decade. The three Canadian Provinces selected for this study were Alberta, Ontario, and Quebec. The U.S. regions studied were the Northeastern U.S., California, and the complete U.S. mix.

The automotive industry is facing a major challenge to incorporate additional powertrain function into smaller more complex packages to meet mandated fuel economy standards and ever increasing world wide competition. An important tool available to meet these challenges is the use of latest Welded Steel Tube technology to develop new concepts for manufacture of the more complex automatic transmission races, gears, hubs and shafts of the future. Advantages of Welded Steel Tubing over seamless tubing, forgings and castings include: Closer raw material tolerances which significantly reduce material waste. Higher productivity, lower tool cost and reduced scrap resulting from lighter machining cuts and/or elimination of entire machining operations. Complex part shape cold formability directly from commercially available material without the need for prior truing operations. Stronger more durable components.

In Laser Transmission Welding (LTW), a laser beam passes through a transparent part and is dissipated as heat in an absorbent material through the use of laser-absorbing pigments such as carbon black (CB). This energy is then conducted further into both parts. Melting and subsequent solidification occur at the interface causing a weld to form between the two parts. Gluing or welding structures to the back of automotive Class-A panels often results in the appearance of undesirable surface deformations on the Class-A side. Through control of the laser welding and material parameters, it may be possible to use contour LTW as a means of joining structures to the back of absorbent Class-A panels without creating these unwanted surface defects. A series of lap welds was made using a range of CB levels and laser powers. A profilometer was used to measure the size and shape of the defects generated on the surface of the black part. Two types of defects were observed: ribs and sink marks.