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Current automotive design practices related to driver visibility are based on static laboratory studies of mostly straight ahead viewing that were conducted by Meldrum and others beginning in 1962. These individual studies have never been replicated either in the lab or in actual driving situations to determine the validity of their procedures. After a thorough review of the literature related to driver eye location and a statistical analysis of previous static eye location data, an experimental design is proposed to determine dynamic eye location distribution characteristics. This design will provide information on: (a) the relationship of static anthropometric measurements to dynamic eye location; (b) the difference between dynamic on-the-road eye location versus static in-the-lab eye location distributions: (c) the effect of different types of vehicle seating package parameters on eye location; and, (d) a validation of previous static eye location studies.

The anatomy of the human respiratory system is detailed. The function of the entire system is shown from inspiration to expiration. Equations are given to illustrate flow-pressure relationships in the airways. Specifics of gas transfer are shown. All these details of physiology and function are necessary for an understanding of the effects of air pollution upon the human respiratory system.

The physiology of carbon monoxide is discussed in the human respiratory system. The details of the relationship of carbon monoxide and hemoglobin are outlined, and the effects of specific concentrations of CO are shown. Acute and chronic exposures to CO create certain effects on the various bodily systems, and these are described in detail.

Aircraft used for business (executive corporate transportation or personal business) and utility purposes now represent about one-third of the total United States aircraft inventory. Data from accident investigation of business aircraft involved in survivable accidents indicate serious injuries and fatality to the occupants occur most frequently as a result of the unprotected head and neck or chest flailing in contact with aircraft controls, instrument panel, or structure. Improvement of current aircraft to provide increased occupant safety and survival during crash impacts is both necessary and feasible. Design considerations include folding seat back locks to prevent collapse, increased seat tie-down to structure, instrument panels and glare shields designed to absorb energy through structural design and padding, stronger seat structure, lateral protection, design and packaging of knobs and projections to minimize injury in contact, and installation of upper torso restraint.

A test series using eight unembalmed cadavers was conducted to investigate factors affecting the creation of cervical spine damage from impact to the crown of the head. The crown impact was accomplished by a free-fall drop of the test subject onto a load plate. The load plate striking surface was covered with padding to vary the contact force time characteristics. The orientations of the head, cervical spine, and torso were adjusted relative to a laboratory coordinate system to investigate the effects of head and spinal configuration on the damage patterns. Load and acceleration data are presented as a function of time and as a function of frequency in the form of mechanical impedance.

High-intensity discharge (HID) headlamps have several advantages over tungsten-halogen headlamps, including greater light efficiency (lumens per watt) and longer life. However, from the safety point of view, the primary attraction of HID headlamps is that, because they produce more total light, they have the potential to provide more useful illumination to the driver. At the same time, there are concerns with the effects of HID illumination on perception of the colors of important objects and glare to oncoming traffic. This paper reviews research evidence that we have accumulated over the past 14 years concerning the potential benefits and drawbacks associated with the use of HID headlighting. We conclude that the evidence strongly supports the use of well-designed HID headlamps.

The paper discusses how atmospheric exposure to lead affects health. Sources of lead in the atmosphere are explored, lead aerosol is described, and the importance of lead in the diet is discussed. Methods of detecting lead in the human system are detailed. The paper suggests that a threshold limit of atmospheric lead be firmly established.

Static deployments of driver-side airbags into the legs of human subjects were used to investigate the effects of inflator capacity, internal airbag tethering, airbag fabric, and the distance from the module on airbag-induced skin abrasion. Abrasion mechanisms were described by measurements of airbag fabric velocity and target surface pressure. Airbag fabric kinematics resulting in three distinct abrasion patterns were identified. For all cases, abrasions were found to be caused primarily by high-velocity fabric impactrather than scraping associated with lateral fabric motion. Use of higher-capacity inflators increased abrasion severity, and untethered airbags produced more severe abrasions than tethered airbags at distances greater than the length of the tether. Abrasion severity decreased as the distance increased from 225 to 450 mm. Use of a finer-weave airbag fabric in place of a coarser-weave fabric did not decrease the severity of abrasion.

Dummy response and restraint configuration factors associated with a known child injury environment were investigated using a spinal-cord injury accident case, a full-scale reconstruction, and sled simulations. The work is one of several studies undertaken in association with the International Task Force on Child Restraining Systems to support the development of improved neck injury criteria and restraint systems for young children. A two-vehicle crash involving a restrained child occupant was investigated in detail and reconstructed in full-scale at the Transport Canada Motor Vehicle Test Centre using the CRABI 6-Month dummy. Vehicle damage and crush characteristics closely resembled that of the case vehicles. Dummy instrumentation included head and chest accelerometers and upper and lower neck transducers. The case occupant had been facing forward and had sustained a contusion of the spinal cord at T2 that resulted in paraplegia.

Although biomechanics models can predict the stress on the musculoskeletal system, they cannot predict how the muscle load associated with exertion is perceived. The short-term goal of the present study was to model the perception of effort in lifting and reaching tasks. The long-term goal is to determine the correlation between objective and subjective measures of effort and use this information to predict fatigue or the risk of injury. Lifting and reaching tasks were performed in seated and standing situations. A cylindrical object and a box were moved with one hand and two hands, respectively, from a home location to shelves distributed in the space around the subject. The shoulder and torso effort required to perform these tasks were rated on a ten point visual analog scale.

Interference between physical objects in the workspace and the moving human body may cause serious problems, including errors in manual operation, physical damage and trauma from the collision, and increased biomechanical stresses due to movement reorganization for avoiding the obstacles. Therefore, a computer algorithm to detect possible collisions and simulate human motions to avoid obstacles will be an important tool for computer-aided ergonomics and optimization of system design in the early stage of a design process. In the present study, we present a method of modifying motions for obstacle avoidance when the object intrudes near the center of the planned motion. We take the motion modification approach, as we believe that for a certain class of obstacle avoidance problems, a person would modify a pre-planned motion that would result in a collision to a new one that is collision-free, as opposed to organizing a totally unique motion pattern.

A quasi-dimensional, multi-zone, direct injection (DI) diesel combustion model has been developed and implemented in a full cycle simulation of a turbocharged engine. The combustion model accounts for transient fuel spray evolution, fuel-air mixing, ignition, combustion and NO and soot pollutant formation. In the model, the fuel spray is divided into a number of zones, which are treated as open systems. While mass and energy equations are solved for each zone, a simplified momentum conservation equation is used to calculate the amount of air entrained into each zone. Details of the DI spray, combustion model and its implementation into the cycle simulation of Assanis and Heywood [1] are described in this paper. The model is validated with experimental data obtained in a constant volume chamber and engines. First, predictions of spray penetration and spray angle are validated against measurements in a pressurized constant volume chamber.

The relationship between motion and posture was investigated from the kinematics of unconstrained head movements. Head movements for visual gazing exhibited an initial component whose amplitude does not exceed 20.3° for target eccentricity up to 120°. This component was truncated by subsequent corrective movements whose occurrence generally increases with target eccentricity, although with a large variability (R2 ≤ 0.46). The head is finally stabilized at 72% of target eccentricity (R2 ≥ 0.92). These results indicate that the final head posture can be achieved through a number of loosely-programmed kinematic variations. Based on these results, unconstrained head movements were simulated, within the context of application to posture prediction for estimation of the visual field.

Advances in electronic countermeasures for lane-change crashes, including both camera-based rear vision systems and object-detection systems, have provided more options for meeting driver needs than were previously available with rearview mirrors. To some extent, human factors principles can be used to determine what countermeasures would best meet driver needs. However, it is also important to examine sets of crash data as closely as possible for the information they may provide. We review previous analyses of crash data and attempt to reconcile the implications of these analyses with each other as well as with general human factors principles. We argue that the data seem to indicate that the contribution of blind zones to lane-change crashes is substantial.

Some of the best teaching methods are laboratory courses in which students experience application of the principles being presented. Preparing young engineering students for a career in the automotive industry challenges us to provide comparable opportunities to explore the dynamic performance of motor vehicles in a controlled environment. Today we are fortunate to have accurate and easy-to-use software programs making it practical for students to simulate the performance of motor vehicles on “virtual” proving grounds. At the University of Michigan the CarSim® vehicle dynamics simulation program has been introduced as such a tool to augment the learning experience. The software is used in the Automotive Engineering course to supplement homework exercises analyzing acceleration, braking, aerodynamics, and cornering performance. This paper provides an overview of the use of simulation in this setting.