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A new concept is described that permits the electron beam process to be used for final assembly welding of large production parts. With this concept, 70 ft long production joints are being welded by North American Aviation. Using a relatively small portable vacuum chamber that fits on top of the parts to be welded, just the area around the joint is evacuated. Specially designed seals allow the electron gun, mounted on a lid, to slide along the top of the chamber, making 5 ft long runs at speeds up to 60 in./minute.

An electron beam welding process, evolved from its primary use in research and development laboratories to a production method that now gives design and manufacturing engineers a proven means of fabricating large complex structural members of the type used in the aircraft and aerospace industries, is the subject of this paper. Using this method of fabrication, many large complex forgings can be replaced with simpler and less expensive fabricated sections. In a number of applications, these forgings can now be replaced by two or more smaller simpler forgings; smaller forging used in conjunction with standard rolled sections; or assemblies made completely of rolled sections. Large assemblies which are beyond the capability of most forging presses can also be fabricated by the electron beam welding process.

An electronic accelerator pedal has been designed for use on heavy trucks with on-board electronics requiring accelerator position input. The one-piece assembly is a floor mounted treadle design with all required electronics and wiring protected behind the instrument panel. The assembly also has been designed to operate, or be operated by, mechanical devices outside of the cab. It is these features, and others, which allow this assembly to satisfy the concerns and needs of all activities which must interface with the accelerator system.

During the past few years, a combination of political, economic, social, and technological factors have created a new interest in the diagnosis and repair of automobiles. The field received considerable publicity with the introduction by Volkswagen in 1972 of a limited diagnostic system. We find that most auto manufacturers today are either considering or planning to introduce similar systems. This presentation will review some of the systems that have been developed and discuss some possible approaches for the future.

The wide angle air core tachometer has been developed as an alternative to the D'Arsonval type tachometer. Differences between the air core mechanism and D'Arsonval meter movement have forced the design of new drive electronic circuitry which would transform a linear output voltage to two bi-directional output wave forms. Combination of the new circuit and existing gage assembly is built into a tachometer assembly and is being produced in high volume utilizing automated assembly and computerized laser test and adjust equipment. Expansion of the concept will allow application to pressure and temperature gages, pyrometers, speedometers, etc.

The isolation diode discussed in this paper has been developed to provide a simple and reliable switch between the output of the alternator and the storage battery of a car. Its function is to block any flow of current from the battery back to the alternator and at the same time to permit use of the popular charge indicator light. This alternator charging system successfully employs electronic principles in converting alternating current to direct current and in giving complete control of field current without the contact points found in the conventional vibrator type regulator.

It is presented here a specific Instrumentation System to determine the quality of materials. It is based in temperature, resistivity and permittivity inputs to determine the title and density of hydrated ethyl alcohol. It is described a physic modeling, development and experimentation. The presented results seen agree with the proposal. The resulted are integrating at computational unit, permitting application static and dynamic.

AIRPLANE hydraulic braking systems must be designed to have the highest standard of performance without sacrificing reliability. By the use of a multielement oscillograph the various characteristics of the braking system can be recorded simultaneously so that the value of design changes can easily be determined. Oscillograms for a typical aircraft braking system show that relatively minor changes result in a wide differential in performance and emphasize the conclusion that design changes in a hydraulic brake system should be evaluated with the oscillograph.

In this paper, the author analyzes automotive safety issues with respect to the application of electronic technology and presents several development targets for the future. The functions expected of the automobile have been changing steadily in Japan. Environmental concerns, for instance, have taken on increased importance and must be factored into vehicle design during the development process. Safety and security issues also impose rigorous requirements on vehicle design. Various efforts are under way to apply electronic technology to driver support systems and devices with the aim of enhancing safety, though numerous problems remain to be solved.

Electronically controlled systems, originally developed for passenger cars, have been applied to trucks and buses since the early 1980's. With the increase of the objects for those applications their contents have become more and more sophisticated with rapid expansion and growth. This paper has summarized the results of observations on the background situations behind the applications of electronic control systems to trucks and buses in Japan. The status of the electronic applications, in particular to the powertrain, are explained and specific examples are provided. Future trends are also discussed.

The transition towards the “paper-less cockpit” presents an opportunity for transferring approach chart information from the current paper format to an electronic medium. This transfer offers a number of potential benefits, but also raises design issues, that need to be resolved. This paper addresses several issues that are relevant to the electronic depiction of approach information and presents performance data-based design guidelines pertaining to the issues in question: (1) Amount of displayed information or display “clutter,” (2) map orientation, and (3) information location/integration.

In calendar year 1988, data was kept on the build of over one million electronic boards and assemblies. The results of this data gives strong evidence on where to receive optimal value for the dollars spent in the various areas of the electronic assembly process. Failure rates given should give good reference points for expected future programs and enable users to make decisions on process controls and vendor screening.

For management to realize the maximum economic benefits from its equipment, it is necessary to know exactly how that equipment is being used. Electronic auditing, using a new, low-cost event recorder, provides a method of obtaining actual operating data from equipment in a form acceptable to a digital computer containing the mathematical model for the equipment management program.

Agricultural tractors are often subjected to various applications like front end loading work, cultivation work, where frequent forward and reverse gears are needed. Most of Indian agricultural tractors are equipped with mechanical transmission system which demands repeated clutching and de-clutching operation for such applications resulting in increased operator fatigue and lesser productivity. Also need of electronics in Indian agricultural industry for better farm mechanization is growing high. This research work depicts development of electronic bi-directional shifting (power shuttle) control design and calibration for farm vehicle fitted with wet clutch transmission. This research also reduces operator fatigue via frequent directional shift through electronic transmission. The control system is designed without any electronic interfacing with engine and also provides clutch-less gear shifting and auto-launch which offers ease to drive even for novice driver.

The job of the EBD as a sub-system of the ABS system is to control the effective adhesion utilization by the rear wheels. The pressure of the rear wheels is approximated to the ideal brake force distribution in a partial braking operation. To do so, the conventional brake design is modified in the direction of rear axle overbraking, and the components of the ABS are used. EBD reduces the strain on the hydraulic brake force proportioning valve in the vehicle EBD optimizes the brake design with regard to: adhesion utilization driving stability wear temperature stress pedal force

The high penetration rate of ABS in nearly all categories of cars assisted the development of more sophisticated wheel slip control systems. Besides traction and stability control (Automatic Stability Control ASC at BMW) especially Driving Stability Control (DSC) is the most sophisticated stability control system currently under development. The combination of DSC with other chassis control systems, which use brake intervention, becomes more important. To reduce the technical effort of the different systems involved in chassis control, different ways can be considered. To allow for a wider application of a chassis control system network, a more radical approach with higher attention on cost savings is required. A possible solution is the development of an Electronic Brake Management EBM. Different attempts are possible with various electric or hydraulic actuation and modulation concepts.

Since 1996 a 2nd Generation EBS has been available in Europe as an advanced brake system offering a variety of advantages to the OEM as well as to the truck and fleet owner. EBS enhances vehicle safety and improves the braking performance to a “passenger car like” braking feel, allowing less experienced drivers better vehicle handling. The brake lining wear control and retarder integration allow the reduction of operational costs. The safety enhancements achieved by EBS in conjunction with disc brakes, are rewarded by European truck insurance companies by lower insurance fees. The importance of EBS will still gain significantly through the developments in process. EBS is the platform for ESP and ACC, which will be a major contributer to better integration of trucks in dense traffic flow.

The desirable braking system of a land vehicle is that it can stop the vehicle or reduce the vehicle speed as quickly as possible, maintain the vehicle direction stable and recover kinetic energy of the vehicle as much as possible. In this paper, an electronically controlled braking system for EV and HEV has been proposed, which integrates regenerative braking, automatic control of the braking forces of front and rear wheels and wheels antilock function together. When failure occurs in the electric system, the braking system can function as a conventional man-actuated braking system. Control strategies for controlling the braking forces on front and rear wheels, regenerative braking and mechanical braking forces have been developed. The braking energy that can be potentially recovered in typical driving cycle has been calculated. The antilock performance of the braking system has been simulated.

To improve engine performance, reduce air pollution, and increase spark plug life, electronic ignition redesign may be necessary. This report covers the advantages and some of the practical limitations that can be involved in electronic breakerless inductive storage ignition design. Basic principles such as dwell control are examined in detail. Specific conclusions regarding Darlington coil-switching transistors and current-limiting vari-dwell ignition circuits are drawn.

There is evidence that for some types of aircraft electronics equipment, reliability and development growth testing (RDGT) is very effective. However, it has been a slow and difficult process to achieve. The accumulation of vibration damage and wear suffered by electronic equipment test articles during RDGT is a function of the input vibration (random) levels and test durations. Dependence only on design specification requirement input vibration levels and durations to determine RDGT test parameters can lead to excessive overtest. It has been found that excessive accumulations can result from unexpectedly high nonlinear responses. The test article qualification vibration specification requirement levels and durations are also often pivotal in determining the RDGT vibration input level. This approach can lead to rapid overtest where long-duration vibration exposure occurs, such as in RDGT.