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This paper describes Programmed Ride Control (PRC), the automatic adjustable shock absorber system designed and patented by Ford Motor Company. The system utilizes low shock absorber damping under normal driving conditions to provide soft boulevard ride, automatically switching to firm damping when required for improved handling. The system's microprocessor control module “learns” where the straight ahead steering wheel position is, allowing the system to respond to absolute steering wheel angle. A closed loop control strategy is used to improve system reliability and to notify the driver in the event of a system malfunction. Fast acting rotary solenoids control the damping rate of the shock absorbers.

This paper reports the analytical procedure developed for a simulation of knee impact during a barrier crash using a hybrid III dummy lower torso. A finite element model of the instrument panel was generated. The dummy was seated in mid-seat position and was imparted an initial velocity so that the knee velocity at impact corresponded to the secondary impact velocity during a barrier crash. The procedure provided a reasonably accurate simulation of the dummy kinematics. This simulation can be used for understanding the knee bolster energy management system. The methodology developed has been used to simulate impact on knee for an occupant belted or unbelted in a frontal crash. The influence of the vehicle interior on both the dummy kinematics and the impact locations was incorporated into the model. No assumptions have been made for the knee impact locations, eliminating the need to assume knee velocity vectors.

In vehicle crash tests, an unbelted occupant's kinetic energy is absorbed by the restraints such as an air bag and/or knee bolster and by the vehicle structure during occupant ride-down with the deforming structure. Both the restraint energy absorbed by the restraints and the ride-down energy absorbed by the structure through restraint coupling were studied in time and displacement domains using crash test data and a simple vehicle-occupant model. Using the vehicle and occupant accelerometers and/or load cell data from the 31 mph barrier crash tests, the restraint and ride-down energy components were computed for the lower extremity, such as the femur, for the light truck and passenger car respectively.

A theoretical math model was created to assess the net effect of aging populations versus evolving system designs from the standpoint of thoracic injury potential. The model was used to project the next twenty-five years of thoracic injuries in Canada. The choice of Canada was topical because rulemaking for CMVSS 208 has been proposed recently. The study was limited to properly-belted, front-outboard, adult occupants in 11-1 o'clock frontal crashes. Moreover, only AIS3+thoracic injury potential was considered. The research consisted of four steps. First, sub-models were developed and integrated. The sub-models were made for numerous real-world effects including population growth, crash involvement, fleet penetration of various systems (via system introduction, vehicle production, and vehicle attrition), and attendant injury risk estimation. Second, existing NASS data were used to estimate the number of AIS3+ chest-injured drivers in Canada in 2001.

Most automobiles, at certain speeds with at least one window open, develop a pulsating pressure which is felt mainly through the ears and is objectionable to the occupants. While this “aerodynamic wind throb” is noticeable over a range of speeds, there is a fairly pronounced peak in the effect at one speed. This problem is studied analytically and experimentally. It is established that the car is a dynamic system consisting of a Helmholtz resonator excited by an edge tone. It is shown that the trouble can be corrected by changing the natural frequency, minimizing or eliminating the excitation, or increasing damping of the system.

This paper outlines an approach to highway transportation research which considers the interrelationship of the major subsystems. It describes the framework, the variables, surveillance techniques, and new vehicle instrumentation. A model is described which serves as the basis for field testing and subsequent mathematical analyses. Surveillance systems including instrumented vehicles, ground, aerial, and space platforms are required as components of a real-time system. A research project, designed to evaluate driver stress, is discussed and sample computer data are shown.

The intent of this paper is to summarize the work of the V8 power plant intake manifold radiated noise study. In a particular V8 engine application, customer satisfaction feedback provided observations of existing unpleasant noise at the driver's ear. A comprehensive analysis of customer data indicated that a range from 500 to 800 Hz suggests a potential improvement in noise reduction at the driver's ear. In this study the noise source was determined using various accelerometers located throughout the valley of the engine and intake manifold. The overall surface velocity of the engine valley was ranked with respect to the overall surface velocity of the intake manifold. An intensity mapping technique was also used to determine the major component noise contribution. In order to validate the experimental findings, a series of analysis was also conducted. The analysis model included not only the plastic intake manifold, but also the whole powertrain.

A study was conducted to rank 34 ergonomic characteristics of automobiles by their degree of importance to older and younger drivers. The older drivers were students in AARP driver education classes; the younger drivers were students in university classes. Three geographic locations were sampled. The primary variable analyzed was age, but geographic location, gender, driving experience, and use of glasses were also investigated. Of the characteristics that were found to be of more than average importance to older drivers, seven were appreciably more important to older drivers than to younger drivers with the “control of glare light” being the most dominant.

Obstacle detection technology has made significant progress in the last five years in the important product areas of quality, performance and affordability. Ford Motor Company's market research indicates that our customers are very interested in new safety features. Drivers consider obstacle detection and collision warning technology as the next breakthrough in safety technology. Ford recognizes the importance of moving from the collision mitigation to the collision avoidance paradigm. Fortunately, the first step in collision avoidance can be taken by equipping the vehicle with reliable and affordable obstacle detection sensors

Side impact collisions account for about 29% of all vehicle occupant fatalities and for about one-fifth of all the “harm” to vehicle occupants. This paper addresses many aspects of side impact induced injuries which vehicle planners and designers may choose to consider during the evolution of a vehicle design. The proposed NHTSA side impact test, side impact dummies, the biomechanics of different human body areas and general concepts for increased occupant protection are discussed from a theoretical point of view. It is believed that this paper or a future update of it, can only become a useful tool when there is general agreement that it reflects solid biomechanical direction which in turn, can be reflected in actual, practicable, responsible hardware design.

Evolving the current state of the art Hybrid Technology for vehicles with plug-in capability will yield three significant results, the displacement of petroleum with electricity for transportation, improved efficiency and reduced emissions. As the technology evolves from the Ford Escape Hybrid Plug-In demo fleet, Ford is in the final stages of development of the C-Max Energi, which will be delivered in 2012 as a highly efficient, full purpose vehicle designed to meet customer expectations without compromise. Presenter Charles Gray, Ford Motor Co.

This paper describes a new, open architecture data acquisition and calibration system, called CALVIN, developed for use in the automotive environment. The design is standards based and allows for growth with future technological breakthroughs. A major driver for the design has been the need to use commercial tools and capabilities. CALVIN, based on Windows95/NT/98 and with the careful partitioning of the hardware and software, has allowed the system to achieve the goals of de-coupling the vehicle calibration development process from the tool while allowing for the protection of user-specific intellectual property. The distributed nature of the design optimizes both the utilization cost and performance and thus, allows for an easy growth path as the environment and needs change. Automation of data acquistion and calibration is available through applications that are compatible with OLE/COM such as Visual Basic and C++.

THE study of engine life, carried out by investigating engine wear in typical service, and by then striving to find the most effective ways of controlling it, forms the basis of this paper on contaminants in lubricants. The investigation involved a study of engine wear in 20,000 miles of operation typical of the average driver. The average driver was selected by using test cars from an employee transportation car pool. At the conclusion of the tests it was found that the use of the full-flow oil filter proved to be the best method for restricting engine wear caused by contaminants that get inside the engine. It was also shown that after successfully eliminating large, solid particles, further restriction of engine wear would depend upon the ability of the oil to lubricate, and upon the engine design to provide the oil supply in a manner suitable for lubrication of each part of the engine.

The development and implementation of a cathode-ray tube (CRT) display automotive information center with navigation feature is described. A structured approach to the TRIPMONITOR software graphics system design is explained. It is shown that beneficial results occur when various features are grouped together into one display and operation system. Emphasis is placed on the human factors of this next generation driver's aid.

Torque controls for the engine and electric motors in a Powersplit HEV are keys to the success of balancing fuel economy, driveability, and battery power control. The electric variable transmission (EVT) offers an opportunity to let the engine operate at system-optimal fuel efficient points independently of any load. Existing work shows such a benefit can be realized through a decentralized control structure that translates the driver inputs to independent engine torque and speed control. However, our study shows that the decentralized control structures have a fundamental limitation that arises from the nonminimum phase (NMP) zero in the transfer function from the driver power command to the generator torque change rate, and thus not only is it difficult to obtain smooth generator torque but also it can cause violations on battery power limits during transients. Additionally, it adversely affects the driveability due to the generator torque transients reflected at the ring gear.

The vehicular illumination system has undergone considerable technological advances in recent decades such as the use of a Light Emitting Diode (LED) and HID (high intensity discharge) lamps. However, the challenges to develop a global beam pattern for ECE markets have been quite difficult due to different needs in different regions. Global programs have to deal with the differences among costumer needs and desires. This paper shows the challenges to understand the different needs and highlights the opportunities for the future to improve road illumination and the driver's safety adopting simulations and different road scenarios.

It is frequently desirable to construct a characterization of vehicle deceleration which is significantly simplified from its actual time history. A number of interesting techniques have been developed to perform this characterization based upon polynomial and Fourier-type series approximations and utilizing goodness of fit criteria related to both least squared error and the satisfaction of boundary conditions. Extensive mathematical occupant simulations indicate that characterizations involving as few as four parameters are adequate to describe the primary effects of complex vehicle deceleration time histories as they influence occupant dynamics with conventional restraint systems.

The objectives of this study were a) to determine how expert judges categorized valid Integrated Vehicle-Based Safety Systems (IVBSS) Forward Collision Warning (FCW) events from review of naturalistic driving data; and b) to determine how consistent these categorizations were across the judges working in pairs. FCW event data were gathered from 108 drivers who drove instrumented vehicles for 6 weeks each. The data included video of the driver and road scene ahead, beside, and behind the vehicle; audio of the FCW alert onset; and engineering data such as speed and braking applications. Six automotive safety experts examined 197 ‘valid’ (i.e., conditions met design intent) FCW events and categorized each according to a taxonomy of primary contributing factors. Results indicated that of these valid FCW events, between 55% and 73% could be considered ‘nuisance alerts’ by the driver.

Each supplier in the power tool industry offers unique tool features and packages. Competition and widespread individuality among manufacturers make it difficult to compare current air and new DC electric power tools. This experimental study compares air and electric hand-held tools based on laboratory testing and research of significant tool characteristics including heat buildup, tool impulse, cycle time and cost. Heat buildup in electric tools raised concerns as well as tool speed, although electric tools were in some instances only slightly slower than air tools. Electric tools, in general, do not have a lower torque-reaction impulse than air tools, but the correlation between tool-shutoff impulse and operator comfort remains unclear. Electric tools are more energy efficient than pneumatic tools, but their initial investment cost greatly outweighs the payback through reduced power usage.

The safety and comfort aspects of passenger cars are significant sales argument and have become a topic of rising importance during the development process of a new car. The objective of this study is to compare the performance of several current model vehicles, highlight the drawbacks of current defrosting/demisting systems and point the way to improved passive mechanisms. The investigation is experimental. The experiments are carried out using full-scale current vehicle models. The results show that the current designs of the defroster nozzle give maximum airflow rates in the vicinity of the lower part of the windshield, which decrease gradually towards the upper parts of the windshield. This hinders and limits the vision of the driver, particularly at the top of the windshield, which can be uncomfortable and indeed dangerous.