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The lead-acid couple is potentially capable of fulfilling the battery requirement for high performance electric delivery vehicles in the one tonne payload category. Development of such a battery, combining high energy density and good cycle life, involves extensive and painstaking testing. During the course of the Lucas development programme test methods and procedures have been evolved to ensure that the battery array with its supporting equipment is capable of fully performing the tasks required of it in such an application. Much of the experience gained is applicable to any electrochemical couple being developed for electric vehicle use.

A cylinder pressure time history has long been used as an indication of the performance of internal combustion engines. Recently the use of cylinder pressure has been proposed for the knock adaptive closed loop control of spark advance (1, 2)*. The ultimate practicality of such a scheme depends heavily on the cost and reliability of a sensor to make this measurement. This paper describes the design, associated analysis, and the experimental performance of a potentially inexpensive sensor. The transducer is shown to be suitable for determination of the crank angle at the peak cylinder pressure and for detection of incipient detonation through the associated high frequency cylinder pressure oscillations. Furthermore, implementation of the sensor in a closed loop spark control system is briefly described. The sensor has proven to be adequate for spark advance control purposes.

The change in the resistance of titanium dioxide with oxygen partial pressure is utilized to obtain an air-to-fuel ratio sensor. TiO2 material properties, sensor components and performance characteristics are discussed. Some results of engine dynamometer and vehicle tests of sensor performance and durability are presented.

High-quality, low-cost automotive sensors are the key to making precise electronic engine control practical. This paper describes four automotive sensors: a temperature sensor, a linear position sensor, a rotary position sensor, and a crankshaft position sensor. The description covers the design approach, the test procedures, the production processes, and the quality assurance measures followed by an established high volume automotive supplier.

The characteristics of ZrO2-type oxygen sensors for closed-loop control of the air-fuel mixture for automotive engines were investigated. New sensors, sensors tested in dynamometers and road vehicles, and lead-poisoned sensors were characterized as to their performance in terms of voltage output, switching response, internal resistance and voltage-λ switching behavior. New sensors behaved as ideal sensors at temperatures above 400°C, and behaved non-ideally at temperatures below 350°C. Sensors subjected to dynamometer and vehicle tests showed a gradual degradation in output voltage and steepness of their voltage-λ switch. Their internal resistances and lean-to-rich switching times increased with use while the rich-to-lean switching times decreased. Self-recovery of a sensor from lead poisoning occurred during subsequent vehicle operation with lead-free fuel.

A new type of Ratiometric Temperature Sensor has been developed which shows considerable promise in the measurement of engine intake manifold fuel/air charge temperatures. The device consists of a conductive plastic potentiometer, driven by an integral bimetallic sensing element. The Ratiometric Temperature Sensor closely tracks the rapidly fluctuating temperature of the fuel/air charge, and provides a linear ratiometric output voltage ranging from 15% to 85% of the total supply voltage over the sensed temperature range of -40°C to +125°C. Output accuracy is ±3°C over a temperature range of +20°C to +100°C.

A new technology for temperature sensors has been developed. The sensors are extremely rugged, capable of withstanding the most rigorous environments, and they are expected to result in very inexpensive product manufacture. This paper discusses the evolution of the design of metal core hybrid substrates and the principles of construction of a temperature sensor as a hybrid circuit on a metal core substrate. Sensor performance characteristics and cost are also explored. A discussion of the linearity of voltage response to temperature is included, and data are presented on the performance of the sensor in various environments. The paper concludes that the new sensor is suitable for operation in all environments found in automotive applications, and that its range is sufficient to accommodate all of the control functions currently found in the literature.

The primary force behind composite materials development for aircraft applications was to achieve weight savings in weight-critical regions. In today's aircraft technology, graphite/epoxy composites are fulfilling this need and are being used as structural materials in the form of cross-plied fiber-reinforced laminates for conventional monolithic wing/empennage skins and substructure, or as face sheets on honeycomb-type structure. All metal components have been replaced by composite structure on aircraft such as the B-1, F-18, and AV-8B. Weight/cost savings were demonstrated for the B-1 aircraft in which not only weight savings, but also cost competitiveness were the goals. The next-generation aircraft will incorporate composites in a significantly larger proportion of the airframe structure to exploit more fully all advantageous characteristics of advanced composite structure (strength, stiffness, tailorability, weight, and fabrication cost savings).

The composite design for the B-1 stabilizer was developed to satisfy all of the form, fit, and functional requirements of the aircraft and to be competitive with the metal stabilizer on both a weight and production cost basis. Actual weights of the composite stabilizer show a 15 percent savings for the total stabilizer and a 21 percent savings for the composite torque box over the existing metal configuration. Cost savings of 17 to 20 percent are estimated in production. The design that evolved from this effort, the test data generated to validate the concept, the fabrication procedures used, and production cost comparisons are presented.

Because of its flexibility and structure, the cervical spine is disposed to various mechanisms of injury: although not so common as injuries caused by head impacts, cervical fractures and/or fracture-dislocations have been reported without direct impact to the head. Some cervical injuries reported have been sustained by wearers of lap and shoulder belts in auto accidents; however, we do not consider belt use a potential hazard because ample evidence has accrued in the medical and engineering literature to document general injury and fatality reduction by use of seatbelts. We believe that in many instances occupants would be more seriously injured or killed were belts not worn. The present paper reviews reports of cervical injuries without head impact found in the literature and case histories of such injuries from the Highway Safety Research Institute of The University of Michigan, as well as experimental studies in animals, cadavers, and volunteer subjects.

In that the neck has a wide range of movements--flexion, extension, lateral bending and rotation, there is a large variety of types of neck fractures and fracture-dislocations. This paper describes these various fractures and dislocations emphasizing the mechanisms as determined from clinical experience and potential, neurological damage. Fractures and fracture-dislocations with and without spinal cord involvement have been extensively described in the medical literature. This paper will give a brief overview of some of the types of fractures, as well as the mechanisms involved in these injuries. For more detailed descriptions, the reader is encouraged to review the articles in the list of suggested readings found in this symposium proceedings.

Radiographs were taken of the cervical spines of male subjects during voluntary motion from full flexion to full extension. Approximately 16 radiographs were taken during a period of 3 1/2 seconds. The resulting motions of the cervical vertebrae were analyzed. A simple pinned-link model of the spine under these conditions is presented.

The cervical cord is a vital structure through which all impulses must travel from the trunk and limbs to reach the brain and also through which all impulses originating in the brain must pass to supply structures in the limbs and trunk. Knowledge of the anatomy of the cervical cord is a requisite to properly localize, diagnose and prognosticate on the effects of the trauma to which the cervical cord is subjected.

The specification of information and specific data on the biomechanical quantities which describe the injury processes produced in the human neck are, at best, minimal. This paper discusses the problems associated with the topic and lists the quantitative information that does exist on the human neck injury tolerance.

Whiplash is a poorly defined term including ligamentous and muscle strains, hematomas, disc injuries, and less frequently, brain, eye and ear injuries. Diagnosis is difficult because clinical signs and Xrays, electromyography and electroencephalography findings are few. Protection and rest will cure most patients within a year but approximately 2/5th of patients have permanent symptoms and disability. Rear-end impact accidents cause the head and neck to hyperextend over the seat back. Whiplash occurs in 38% of exposed occupants. Head rests give protection but differential rebound may occur producing injurious hyperextension and whiplash. The larynx, trachea and esophagus, in front of the spine, are injured by impact against the dash or steering wheel. Airway obstruction may occur and cause death if not restored quickly. Permanent disability can occur because of scarring and partial airway or esophageal obstruction or vocal cord damage.

The need for accurate, high-resolution automobile fuel gauges is becoming increasingly felt and this can best be fulfilled with modern developments of the capacitance-measuring technique used for aircraft fuel tanks. An inexpensive probe is described which can be used, with suitable circuitry, to give a 0.1 gallon resolution and accuracy, from which the influence of slosh and tilt is effectively eliminated. A low-cost measuring circuit is described, based on CMOS astable oscillators, which produces digital readings virtually immune to noise, voltage and temperature changes, and the effects of ageing.

This paper presents an analysis of 67 neck injuries incurred in diving and sliding accidents in swimming pools. The accidents were investigated to establish the appropriate medical and mechanical factors involved. A mathematical model was developed to allow the prediction of the trajectory and velocity of the subjects prior to their injury. Nine of the accidents were selected for real life simulation. The simulation included the selection of test subjects of similar physical build to the accident victims who then performed the maneuvers leading to the injury, but in deeper water. High speed movies (200 frames per second) were taken, above and below the water, to measure the motion. A frame by frame analysis provided data to determine the trajectory and velocity profiles of the test subject. The maneuvers studied included diving from the pool edge, diving from various board types and sliding down various sliding board configurations.

This paper illustrates the design of a linear step actuator. The unit develops 1.1 newtons of axial thrust in .1 mm steps for a total travel of 13.2 mm.

Designing a climate control system for a new highway tractor is a multi-phase project. This paper outlines the process and the various challenges each step presented, starting with outside temperatures and going through zone controls, register placement, system design, heat transfer components and testing. From the different steps emerged a multiple heater/evaporator system with performance superior to existing designs. The system has three sets of controls which provide a means of regulating the temperature in the driver, passenger and sleeper areas of the cab. The paper also describes the various packaging concepts investigated, how the choice of vacuum as a power medium for the controls was selected and briefly outlines the testing conducted on the new design.

The limitations of conventional solenoids will be explained and reasons given to show that as they are made more powerful their speed of operation decreases. HELENOID actuators are capable of armature travel times in less than one millisec irrespective of preloads or masses, despite the larger size and power required as the duty increases. The relationships between eddy currents and flux penetration; materials and flux leakage; inductance and power supply are illustrated, together with the way they are all interconnected and varying with time, requiring a comprehensive computer program to design for optimum performance.