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Video

Fault-Tree Generation for Embedded Software Implementing Dual-Path Checking

2011-11-17
Given the fast changing market demands, the growing complexity of features, the shorter time to market, and the design/development constraints, the need for efficient and effective verification and validation methods are becoming critical for vehicle manufacturers and suppliers. One such example is fault-tree analysis. While fault-tree analysis is an important hazard analysis/verification activity, the current process of translating design details (e.g., system level and software level) is manual. Current experience indicates that fault tree analysis involves both creative deductive thinking and more mechanical steps, which typically involve instantiating gates and events in fault trees following fixed patterns. Specifically for software fault tree analysis, a number of the development steps typically involve instantiating fixed patterns of gates and events based upon the structure of the code. In this work, we investigate a methodology to translate software programs to fault trees.
Video

Visionary's Take: An Engineering Journey into the Marketplace (Part 3 of 3)

2017-10-12
Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.
Video

Visionary's Take: An Engineering Journey into the Marketplace (Part 1 of 3)

2017-10-12
Can you become a visionary or are you born one? How does a visionary capture an opportunity and makes it a successful business? Are engineers more qualified to solve technical problems or run companies? SAE's "The Visionary's Take" addresses these and many other questions, by talking directly with those who have dared to tackle difficult engineering problems, and create real-life products out of their experience. In these short episodes, Sanjiv Singh and Lyle Chamberlain, respectively CEO and Chief Engineer from Near Earth Autonomy, talk about their experience in creating a brand-new company in the UAV world. Founded in 2011, Near Earth Autonomy brought together a group of engineers and roboticists, looking for unconventional solutions to very hard logistics problems, presenting danger to human life. The answers were developed by pushing technology to a higher level, testing quickly and often, and keeping an open mind to alternative ways of framing engineering challenges.
Technical Paper

The Large-Scale Operator's Influence on Design and Construction

1928-01-01
280034
TO solve fleet-operation problems successfully, a professional consciousness is needed among the supervisors and the engineers engaged in the operating field, awakened by analyzing and making known generally the methods and practices used by the operators of individual fleets of motor-vehicles, according to the author. In developing his subject he asks the following questions and comments upon them: Has the operator any influence on design? Is that influence good or not? Whatever the influence is, can it be improved and made more effective? If it can be made more effective, how can this be done? If it cannot be made more effective, what is the reason? Regardless of variations in duties and of conditions in organization, each large-scale operator is vitally concerned with matters of design and construction.
Technical Paper

BURNING KEROSENE IN TRACTOR ENGINES

1917-01-01
170031
The author states as his object a review of what has been done and what must be done to make tractors successful in operating on low-grade fuels, especially kerosene. He takes up in order the four principal methods in common use of applying heat to vaporize kerosene, pointing out the advantages and disadvantages of each method and of its modifications. The author then cites various experiments with different types of carbureters in burning kerosene, drawing at length upon his own experience in this connection. He cites difficulties with gas distribution, manifold condensation, pistons and spark-plugs and points out that carbureter design is inseparable from considerations of tractor engine and manifold design. That better progress has not been made in the past in developing kerosene-burning tractor engines is stated to be largely owing to the fact that there has not been sufficient cooperation between engine and carbureter manufacturers.
Technical Paper

TRACTOR WEIGHT AND DRAWBAR PULL

1920-01-01
200080
The best weight for a tractor of given horsepower must be a compromise based upon a mean of the many conditions to be encountered by a given machine or by different machines of the same model. While the weight logically will bear some relation to the drawbar pull, the latter in turn depends upon tractor speed. The next item is weight distribution, which requires the utmost skill of the designer; this is elaborated and diagrams are shown of tractors operating in comparatively firm and in soft ground, ascending a grade and when the drive-wheels are mired. The four-wheel-drive tractor requires a modification of the foregoing analysis and the diagrams are applied to afford a similar analysis for this type. The author's conclusion is that, while careful engineering will make the light-weight tractor of conventional type stable under most conditions, there is a possibility that any future trend toward lighter machines will open the field to other types.
Technical Paper

FIFTH-WHEEL MOUNTINGS ON TRACTOR SEMITRAILERS

1948-01-01
480211
IT seems desirable to increase appreciably the amount of kingpin offset in tractor semitrailer combinations, according to Mr. Horine, who discusses the effect of kingpin offset on load distribution, clearance angle, traction, braking, steering, maneuverability, and riding qualities. The author also explores the geometric limits on how far ahead of the tractor axle the kingpin may be placed.
Technical Paper

Hydraulic Torque Converter-Common-Law Spouse of the Heavy-DutyTruck

1953-01-01
530243
THE case for the operator of the heavy-duty truck is considered in this paper. The author points out that the average driver feels that standard truck components are being assembled without regard for specific problems which must be met and solved on the road. An objective look at torque-converter transmissions in use indicates the serious need for specific study of truck applications. The author describes the operation of logging and ore trucks in relation to loads and roads. He also gives performance data on short hauls handled by one driver, and on long runs where as many as 20 different drivers are required. He states that trucks and related rubber-tired vehicles present one of the largest potential markets available to the torque-converter transmission manufacturer if he will but design for the specific needs of that market.
Technical Paper

A METHOD of Predicting LIFE of Tractor BEARINGS

1944-01-01
440145
METHOD of selecting sbaetiasfraicntogrsy for the transmissions and final drives of pneumatic-tired tractors that depends on a knowledge of average operating conditions is reported by John Borland. The well-known method of rating bearings on a fatigue basis is, according to tests carried out by Mr. Borland, a reasonably accurate way of predicting bearing life when loading conditions are definitely established. However, the tables that have been compiled by the bearing manufacturers are satisfactory for determining bearing life only of bearings subjected to a constant load at a constant speed. Since tractor transmissions are subjected to as many different loading conditions as there are speed changes provided in the tractor, tractor transmission bearings cannot be selected directly from these tables. They must be used in conjunction with the formula for determining a factor called weighted life.
Technical Paper

WHAT DO FLEET OPERATORS WANT in POST-WAR TRUCKS?

1944-01-01
440159
NEARLY 300 fleet operators were questioned by Mr. Laurie to gather data for this paper on what features the users of trucks would like to have the manufacturers incorporate in post-war trucks. The cooling system is one important item that came in for its share of criticism. For example, maintaining the proper coolant level is most important, and yet many of today's systems require filling into the filler neck before the liquid level can be seen. Petcocks or sight gages properly installed could solve this problem, according to Mr. Laurie. Accessibility for maintenance should also be improved in the post-war truck. Some of today's trucks have batteries that are not located for ease of servicing and spark plugs that it is almost impossible to remove and replace. Improvements should also be possible in cold starting of the engine, based on the experience of the Army in cold climates.
Technical Paper

TRACTOR SERVICE REQUIREMENTS

1921-01-01
210031
The paper treats of the service, commercial and technical aspects of the subject in turn. The author calls attention to the fact that there can be no such thing as free service, because the customer pays in the end, and gives a specific definition of service. He argues that the engineering departments should urge upon merchandising departments intelligent distribution through dealers, the stocking of an adequate supply of parts and the maintaining of a well qualified mechanical force for the purpose of making engineering development work in the form of farm power automotive apparatus effective. There is a great need for a suitable system of training mechanics for tractor service work, and there should be a definite plan to assure that men making repairs and adjustments in the field are well qualified.
Technical Paper

Maintenance of a Concentrated Fleet of Large Trucks

1938-01-01
380132
MAINTENANCE economy is seldom a realization unless sufficient consideration has been given to the major factors entering into the cause for maintenance. The expenditures necessary to correct normal wear conditions often represent a very small portion of the total maintenance cost. The operator is presented too frequently with the problem necessitating design corrections before the truck has operated many thousand miles. The responsibility for failures of this nature may rest with either the purchaser or the manufacturer. The purchaser may, due to insufficient thought having been given to the contemplated assignment of the truck, misinform the manufacturer as to the load to be carried or the terrain to be traversed; or his appropriation for purchase may be insufficient for a suitable piece of equipment. The manufacturer, on the other hand, may accept the order, knowing that he cannot furnish suitable equipment.
Technical Paper

The Economics of Truck Selection

1938-01-01
380122
THE truck manufacturers have made available to fleet operators a wealth of truck chassis with sufficient models and interchangeability of units to create special models to meet any transportation job requirements no matter how particular or peculiar. Within reasonable limits, the first costs of these chassis are indicative of relative chassis strength, durability, and ability. The selection of a chassis cannot be made from first cost or from operating cost expectancy alone, for these two go hand-in-hand to form the total cost and either may be increased with impunity if the overall cost of transporting the product is thereby decreased. One of the most important requirements in the selection of a chassis is a thorough operation and transportation job-analysis. Other considerations include availability of service, inherent safety, legal limitations, and appearance.
Technical Paper

Why Not 125 BMEP in an L-Head Truck Engine?

1939-01-01
390130
HIGH output per cubic inch of piston displacement is desirable not alone for the purpose of being able to transport more payload faster, but more particularly for the invariably associated byproduct of lower specific fuel consumption, and especially at road-load requirements. The only way of accomplishing this purpose is through the use of higher compression ratios, and the limiting factors for this objective are fuel distribution and the operating temperatures of the component parts. A manifold is proposed which not only definitely improves distribution at both full and road loads, but has the inherent additional advantage of reducing the formation of condensate, thus still further facilitating a reduction in road-load specific fuel consumption. Hydraulic valve lifters, obviation of mechanical and thermal distortion, and controlled water flow are the essentials in improved cooling.
Book

Managing Complexity

2014-01-01
Managing Complexity is the first book that clearly defines the concept of Complexity, explains how Complexity can be measured and tuned, and describes the seven key features of Complex Systems: 1. Connectivity 2. Autonomy 3. Emergency 4. Non-equilibrium 5. Non-linearity 6. Self-organisation 7. Co-evolution The thesis of the book is that complexity of the environment in which we work and live offers new opportunities and that the best strategy for surviving and prospering under conditions of complexity is to develop adaptability to perpetually changing conditions. An effective method for designing adaptability into business processes using multi-agent technology is presented and illustrated by several extensive examples, including adaptive, real-time scheduling of taxis, see-going tankers, road transport, supply chains, railway trains, production processes and swarms of small space satellites.
Technical Paper

Current Status of Fuels and Lubricants from Construction Users Viewpoint

1963-01-01
630436
Many technological advances have taken place during the past decade which have enhanced the status of fuels and lubricants for construction equipment. Standardization and simplification of recommendations have been accelerated. These contributions have helped us to gain economy and reliability of operation. Petroleum product suppliers, construction equipment manufacturers, and the users of both products have contributed to these advances. Above all, the cooperative effort of the producer and consumer members within the framework of professional organizations has had a stimulating effect. This paper discusses the current status of fuels and lubricants for construction equipment; equipment descriptions, fuels, lubricants, and problem areas are presented.
Technical Paper

The Design and Application of Four-Wheel-Drive AG Tractors

1969-02-01
690726
Four-wheel drive agricultural tractors are finding wide acceptance in the large tractor market. There are two basic design concepts, rigid frame and articulated, both of which have distinct advantages. At present the relatively low production volumes demand a modular design approach. The future will see a trend toward integrated components. There are seven manufacturers presently offering models that together cover the range of 100-220 drawbar hp. This paper presents a comparison of marketing and component features.
Technical Paper

Procurement and Development of the M715 1¼ Ton Truck Series

1970-02-01
700014
The M715 truck is an industry designed, Military approved vehicle embodying optimum reliability, mobility, and maintainability, with reduced initial cost, lower operating and upkeep expense per ton mile, and a 66% increase in the rated payload capacity over the previous M37, 3/4 ton vehicle which it succeeds. This paper describes the contract concept, research and vehicle development, the rigorous testing procedures, problems and corrections, all of which have produced achievements beyond expectation.
Technical Paper

Family of Military Engineer Construction Equipment (FAMECE)

1969-02-01
690579
A review of the U. S. Army concept for development of a Family of Military Engineer Construction Equipment (FAMECE) in light of basic problems facing the military engineer is presented. Problems evaluated are air and ground mobility, increased productivity, maintenance of unit integrity, and standardization of unit design. Although in the past the military attempted to develop lightweight, compact equipment which could be disassembled, such equipment did not perform to operational standards under field conditions. This led, however, to the FAMECE concept of a power module being utilized with a wide variety of work moduli. It addresses the problems of mobility, standardization, and logistics. At present, the program is well along in terms of conceptual design and is backed by several years of research and development efforts.
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