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Many anxieties have been generated concerning the introduction of an air cushion passive restraint system in automobiles for a variety of reasons; but, one of the most prevalent anxieties stems from the common lack of understanding relative to the functioning characteristics and safety of the inflator which is to contain some quantity of pyrotechnic material - this inflator becoming a permanent fixture in the passenger compartment of the vehicle. This presentation discusses in understandable detail the physical and functional characteristics of the basic pyrotechnically augmented inflator and how each of its major components contribute to form a controllable system which can be varied to meet various systems demands. It further discusses a proposed marriage of inflator and sensor in a system totally restricted from functioning by any other mode than the properly prescribedcrash energy signature.

Part I of this paper discusses a computer model of a hybrid air cushion inflator which models existing systems to a high degree of accuracy. Gas generator size and ballistic properties, stored gas composition, storage pressure, volume, temperature, and receiving tank parameters can be varied to accurately predict the effects of system changes on inflator performance. In Part II, an approach for analytically obtaining equations of motion for torsos during contact with gas cushions in frontal collisions and subsequent ride-down characteristics is developed. From these equations, calculations of torso “g” forces, cushion pressures and other system parameters can be made. It is then possible to optimize these parameters in terms of desired torso response under a variety of design criteria as a guide to system design and experimental verification.

The initial air cushion research by Ford and suppliers has primarily involved full-sized cars. Technical approaches for these cars in packaging, kinematics, sensing and deployment are presented. Also, efforts to meet the requirements of the potential restraint standard as well as to resolve “real world” problems are discussed.

One of the sub-systems of air bag passive restraint systems presently under examination for automotive application is the energy source sub-system. The function of the energy source is to provide, release, and control a volume of gas at a rapid rate to inflate the air bag. Three basic types of energy sources will be described, these being stored gas, generated gas, and hybrid sources. Both liquid cooled and gas cooled hybrid sources are mentioned. The automotive requirements for application of energy sources are discussed in terms of performance objectives for passive restraints, particularly for front seat passenger air bags. The requirements include minimum package size and weight, ability to perform in hot and cold as well as normal environments, freedom from degradation during the service life, high reliability, controlled toxicity and heat, and ability for safe disposal during vehicle recycling. Two new types of inflation systems which are to improve versatility are mentioned.

Development of reliable, low-cost inflators without toxic exhaust products is the key to successful inflatable occupant restraint systems. The characteristics and performance of gas generators and aspirator inflators are presented, together with cushion gas characteristics. Toxicity considerations, including both gaseous and aerosol constituents, are discussed. Results indicate that inflators can be produced that will meet stringent, yet realistic, toxicity requirements. The feasibility of the aspirator inflator has been established, and this unique device offers distinct and significant advantages over conventional direct inflation devices.

Gas generators for filling auto air cushions have been developed in several compact sizes and configurations. All-solid chemical-generating compositions have been developed to give nearly pure nitrogen gas. Other compositions developed give mainly carbon dioxide. Gas cushions ranging in size from 1-12 ft3 have been inflated. Deployment time, bag temperature, and sound level are within safe limits. Toxicity tests have been performed on dogs without harmful effects being observed.

In fulfilling their roles in today's sensitive environments, engineers and their works bring about a wide variety of reactions. The resulting consequences on the people who must interact with them, and on nature that must compete with them, are becoming subject to critical social evaluation in the context of awakening concerns for environment, community values, and social consciousness. Engineers and engineering educators should study and measure these impacts, develop an analytical awareness of them, and attempt to develop a methodology for forecasting the impacts of proposed engineering works and products. The planning, designs, and actions of engineers should reflect a philosophy that places the highest of values on the enhancement of the quality of living.

Furnishing transit service to smaller urban communities in a way that is workable physically and economically is the main point of discussion in this paper. The important issues relating to public transportation in small urban areas include financing, community service, institutional considerations, and image. Finding the best system for each respective community is the relevant problem, the systems must be planned to enable each community to grow and prosper.

A survey of industrial control computer applications presently operational in this user's facilities revealed an approximate 50/50 division between those that were internally and externally implemented. Problems encountered in the planning, launching, and follow-up phase of system installation were found to be common to both internal and external system implementations and are categorized and evaluated as being inherent and environmental in nature. In an effort to avoid anticipated problems characteristic of a computerized installation, proper staffing as an inhouse project team is essential. During the process of developing inhouse talent, three plateaus of system implementation maturity are attained. These plateaus range from complete dependency upon outside assistance to “do it yourself” inhouse implementation. Flow charts are developed to depict typical decision paths leading to a plateau of system implementation most appropriate for the particular user “turnkey dilemma.”

The use of computers and integrated-systems concepts has made computerized auditing techniques necessary. This paper discusses one such auditing system and describes the Ford part numbering and usage condition coding systems which are fundamental to its design. As part designs are released for production by Engineering, these parts are accompanied by a definition of the conditions under which the design is to be used for production and the required quantity per unit. The information is needed in calculating tooling requirements, scheduling manufacture and procurement of parts, and controlling inventories.

Managing and supervising to achieve favorable results in motivating engineering employees is related to the planning, budgeting, and administration practices recommended for a product engineering activity within a corporation environment. The information and suggestions included in this paper are based upon 23 years of experience and have produced favorable results. Other material in the paper is considered valuable in avoiding negative results in motivation. The paper concludes with specific suggestions for supervisors and managers of engineering employees.

Motivating engineers can be very stimulating and rewarding. It takes the personal commitment of the manager of these human resources to set the climate for growth and development. This climate can provide only up to 20% of the development of an individual. The remaining 80% of development is the personal commitment of the individual. Since developing the human resources is one of the most important responsibilities of an engineering manager, the following attributes are important: 1. Works effectively with others. 2. Establishes a climate for growth. 3. Is a good communicator. 4. Is versatile and able to cope with change. 5. Sets objectives for himself and with his people. 6. Manages time wisely. 7. Is enthusiastic and positive. 8. Keeps physically fit and mentally alert. 9. Is sensitive to the needs of his people.

Arguments are put forth that the current urban transportation planning process is failing to address itself to the causal factors and elements of the urban environment that creat the demand for travel. The approach to urban transportation analysis and development is argued to be best done through work on special facilities. Special facilities are defined as the basic building blocks of life in the urban environment. The reason for the study of special facilities needs is that the true determinants of travel behavior can be best established at this level. Using trip-aggregate models behavior specific to special facilities is suppressed. The success of disaggregate (individual-based) models in modeling modal choice behavior is extended to the analysis of special facilities. The need for policy-sensitive models further exemplifies special facilities models.

This paper discusses the dramatic change that has taken place in the urban transportation concept. The importance ascribed to social, political, and aesthetic concerns by the transportation planning function has resulted in greater sensitivity on the part of transportation planners to nonphysical elements. Aesthetic and design principles are being identified and are becoming more important in fitting transportation facilities into communities, without disrupting the natural environment. Also discussed are the steps taken by the U. S. Department of Transportation's Office of Environment and Urban Systems to institute a design and development expertise that would be more sensitive to the aesthetic objectives in the metropolitan transportation planning process. The need for reforms within the decision-making process are also discussed.

There are two general approaches to travel demand analysis currently being suggested: one the widely used “Urban Transportation Planning process,” and the other the use of “Direct Demand Models.” Their general forms, strengths, and weaknesses are sketched briefly here, and some problems common to both approaches are investigated. These include the limitations imposed by the single period, static, partial equilibrium nature of the analysis, and the problems raised by the possible existence of multiple equilibria within that framework. The paper advocates research in several directions which would help to alleviate the problems in current procedures, and which also promises to yield some policy guidelines as research progresses.

This paper examines and challenges various established theories of transportation economics. The sad state of our transportation systems prompts this examination. Pollution caused by mass transportation, the high cost, inadequacy, and inefficiency of these systems have all been considered, and combined together indicate the need for improvement.

An attempt is made to show that a transportation system as such is too "open" for sound planning, and that the larger interaction system (including the users of transportation and their bases at home and work) must be considered. This requires a detailed understanding of micro-behavior, social goals, and public policy alternatives in a wide range of situations.

The noise produced by new high-speed rail rapid transit system operations is much less than traditionally expected due to modern design concepts and equipment which include specific features for reducing noise and vibration. Using data obtained from various operational and experimental rail transit vehicles and systems, the noise characteristics to be expected from new and proposed systems and equipment have been determined. The known and specified noise characteristics can be used during the planning of transit systems to determine the expected wayside or community noise levels for various types of way structures, vehicles, and operational conditions, and can also be used to determine design features or system characteristics which should be included for the control of noise. This permits the inclusion of noise as one of the factors affecting system planning and design.

This paper argues that without a clear technically-based philosophy for structuring our cities, an iconography of systems equal to their growth and movement and change, our planning efforts are doomed to failure. Neither the architect, in his preoccupation with individual projects and mere pieces of cityscape, nor the engineer, in his willingness to slice into the living tissue of the city without understanding its socio-environmental pathology, is trained to cope with our problems of urban design. Yet is is the vast technical networks of movement that are the lifeblood of our cities, and have the most promise of providing an infrastructure capable of ordering growth and change in our cities. However, urban sociologists are preoccupied with problems of social diagnosis, architects reject technology as a conceptual skeleton for their esthetic games, and engineers seem unable to grasp the vast esthetic implications of transportation technology in the cityscape of tomorrow.

The increasing public concern in recent years over the problem of environmental noise has resulted in the enactment of technology-based regulatory agencies and statutory measures to control technological applications. Most of the earlier controls, however, were reactive measures rather than positive efforts to assure development of a new technology in the public interest. This situation is beginning to change as new environmental codes are being implemented in various states and cities. This paper describes how the noise factor has influenced the planning of transportation systems by various legislative and regulatory entities at the federal, regional, state, and local levels.