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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.

The purpose of this paper is to discuss the application of control system technology to the design of electronic closed loop controls for the automobile. A number of basic theoretical concepts which are pertinent to automotive problems are discussed; these include open and closed loop control, step response, time delay, and the proportional-integral controller. These concepts are illustrated by an analysis of the stoichiometric air-fuel ratio control problem.

Especially in the United States, but also in Europe, product liability has often been identified as a possible constraint for the successful implementation of electronic driver support systems. This paper broadly examines product liability law in the United States and in Europe. There is a clear and striking difference in the level of litigation against producers, which is much higher in the United States than in Europe. Briefly assessing the concept of a defective product in both European and American law in relation to electronic driver support systems, it is concluded that the most important differences are probably not caused by diverging substantive product liability law rules but rather by other differences between the legal system in the US and in Europe.

As the automotive industries join the Global environment, the component suppliers need to adapt to this reality. This brings new challenges to be accommodated. Conflicting objectives, as seen from a traditional point of view, must be harmonized: Centralization of core development and simultaneous presence in the customer's sites are difficult to manage. A network of technical centers has to be wisely distributed around the world in order to allow for optimum coverage with all potential customers. Also the new tendency of modularity imposes leaving from a pure component design to modules and subsystems integration. This paper gives, based on a real case experience, some insights on best ways to meet these challenges and focus mainly in the task of designing for globally managed car programs. The most common scenario nowadays for a new car program development is to have a central platform design which allows for local market exception needs, These needs will vary from region to region.

This paper presents an Electromagnetic Compatibility (EMC) Test Plan and Procedure for automotive electronic components which predicts the EMC performance in a vehicle. Production representative vehicles for EMC evaluation are often not available in sufficient quantities until late in an electronic component design stage where changes are most costly. This Test Plan and Procedure addresses this problem by allowing early detection and definition of component design deficiencies. Also presented are vehicle and electronic component EMC design practices with low cost being a prime consideration. These practices have been proven effective in the most hostile vehicle noise environments on a number of automotive electronic systems.

The paper details opportunities for electronic control of the pneumatic charging system of an air braked vehicle. Electronic control of the charging and drying functions can result in increased fuel efficiency and improved air quality. Control functions can be used to identify and warn of in-service issues, provide prioritized system charging for faster drive-away, and signal required preventative maintenance. The first portion of the paper describes current industry practice, as well as common issues that can result from those practices. This is followed by presentation of areas of improvement, where specialized control features result in energy savings, air quality increases and maintenance/downtime savings. This portion will focus on adaptive control of components used today, and will briefly discuss opportunities for the next generation of charging system devices. The final section of the paper presents the control logic and vehicle interface allowing for system integration.

An electronic variable valve timing system for a spark ignition engine was designed and built in order to investigate the performance of ideal valve actuation timing and facilitate further research. The solenoid actuated EVVT system was installed on a single cylinder 80 ccm, 1.7 kW Briggs & Stratton SI engine. The system is controlled by a PIC micro-controller unit, which in turn controls a 120V solenoid driver circuit to power the solenoids. The continuous variable valve timing adjustment enables ideal combustion conditions during all speed ranges and loads. This leads to cleaner, more efficient and more powerful combustion once the control algorithm is mapped for all conditions. Furthermore, it makes controlled auto ignition achievable using negative valve overlap, which is a promising emission-reducing combustion mode.

We have developed a new type of system to prevent disc brake squealing. The rotor vibration radiates the squeal noise, therefore if the rotor vibration can be stopped electronically, no squeal is generated. Based on this concept, the Electronic Control Canceling System for a Disc Brake Noise ( ECCN ) was developed for the opposed type brake which has four brake pistons. The ECCN consists of four piezoelectric elements and one electronic control unit, and can stop the low-frequency squeal of 2∼4kHz by using a small amount of energy with the noise dynamometer and the test vehicle.

Increasingly, the exchanges of data in complex ECM (Electronic Control Module) systems rely on multiple communication networks across various physical and network layers. This has greatly increased system flexibility and provided an excellent medium to create well-defined exchangeable interfaces between components; however this added flexibility comes with increased network complexity. A system-level approach allows for the optimization of data exchange and network configuration as well as the development of a comprehensive network failure strategy. Many current ECM systems utilize complex multi-network communication strategies to exchange and control data to components. Recently, Caterpillar implemented an HIL (Hardware-In-the-Loop) test system that provides an approach for developing and testing a comprehensive ECM network strategy.