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CHEVROLET has made its new air-suspension system easily interchangeable in production line assembly with standard full-coil suspension by adopting a 4-link-type rear suspension with short and long arms. A feature of the system is the mounting of the leveling valves within the air-spring assemblies. These valves correct riding height continually at a moderate rate, regardless of whether the springs are leveling or operating in ride motion. The system provides constant frequency ride—ride comfort remains the same whether the car is occupied by the driver alone or is fully loaded.

The overall vision of this project was to develop a new technology that will be an enabler to reduce design and development time of HVAC systems by an order of magnitude. The objective initially was to develop a parametric model of an automotive HVAC Windshield Defrost Duct coupled to a passenger compartment. It can be used early on in the design cycle for conducting coarse packaging studies by quickly exploring “what-if” design alternatives. In addition to the packaging studies, performance of these design scenarios can be quickly studied by undertaking CFD simulation and analyzing flow distribution and windshield melting patterns. The validated geometry and CFD models can also be used as knowledge building tools to create knowledge data warehouses or repositories for precious lessons learned.

THIS description of the hydraulic control used with the hydra-matic transmission reveals how the control operates to change ratios under power without direction from the driver. The control's pattern of automatic shifting for ordinary, high-range driving has been selected as the best compromise between top performance and low ratio of engine noise to wind noise. The control's low range shifts gears according to performance dictates alone, furnishing greater power for extreme conditions at low speeds and enabling the driver to use his engine as a brake on steep descents. Heart of the control system is a double hydraulic governor, sensitive both to car speed and throttle opening. THIS paper, as well as the two that follow, one by Messrs. Nutt and Smirl and the other by Mr. Kimberly, make up a symposium on automatic transmission components presented at the 1947 SAE Summer Meeting.

This study examined whether the effect of subsidiary tasks on driving performance can be predicted from stationary (static) testing. Alternative methods for assessing the performance of drivers during their use of in-vehicle information systems were examined. These methods included static testing in stationary vehicles, as well as dynamic, on-road testing. The measures that were obtained from static tests were evaluated in terms of how well they could predict measures obtained from driving performance during on-road testing (which included concurrent use of secondary information systems). The results indicated that measures obtained in static test settings were highly correlated with corresponding measures obtained from on-road performance testing.

This study assembled a database of anatomic dimensions of Indy Car drivers and developed procedures that can be used as models for future compilations of anatomic data from specialized populations. The database defines the body configuration for the Indy Car driver population and indicates that the current HYBRID III, midsize male crash dummy will provide a reasonable approximation of that population if used in investigations involving issues of crash protection. This study took advantage of a unique opportunity to assemble an anthropometric database from a specialized population which was compared to an existing database collected from a comparable sub-set of the United States population.

This paper describes a test of 2500 General Motors passenger cars equipped with anti-lacerative windshields and driven in rental fleets. It also de840391 scribes the laboratory tests conducted prior to the fleet installation of the test windshields. Evaluation of haze development caused by abrasion of the anti-lacerative surface will take several more years of exposure. Other test results have been encouraging, except for the difficulties encountered in the removal of stickers and decals from the inner surface.

An objective, biomechanically based assessment is made of the risks of life-threatening brain injury of frontal crash test results. Published 15 ms HIC values for driver and right front passenger dummies of frontal barrier crash tests conducted by Transport Canada and NHTSA are analyzed using the brain injury risk curve of Prasad and Mertz. Ninety-four percent of the occupants involved in the 30 mph, frontal barrier compliance tests had risks of life-threatening brain injury less than 5 percent. Only 3 percent had risks greater than 16 percent which corresponds to 15 ms HIC > 1000. For belt restrained occupants without head contact with the interior, the risks of life-threatening brain injury were less than 2 percent. In contrast, for the more severe NCAP test condition, 27 percent of the drivers and 21 percent of the passengers had life-threatening brain injury risks greater than 16 percent.

The purpose of the Cadillac DeVille Night Vision System is to provide drivers with visual information beyond with the range of their headlamps. It can also help drivers see beyond the glare of oncoming vehicle’s headlamps. With increased visual range the driver may have more time to react to potentially dangerous situations. The system consists of a thermal imaging camera, a head-up display, and image controls. The camera senses temperature differences of objects in the road scene ahead and creates a thermal image of the scene. The head-up display projects this image onto the windshield creating a virtual image that appears at the front edge of the vehicle’s hood just below the driver’s line of sight. This paper will describe the system requirements and parameters of the 2000 Cadillac DeVille Night Vision system.

The air bag safety issues became evident in 1995 and other factors have conjoined to change the climate regarding motor vehicle safety. Traditionally, motor vehicle safety issues have been evaluated based upon the effects upon average adult males. The new climate requires consideration of the effects on persons of differing size and gender. By including consideration of children and women, rulemaking and the applied technologies are able to better optimize safety than is the case when rules are focused only on the average adult male. Automotive electronics serves a key role in the migration from a one-size-fits- all protection to a more customized protection for a variety of occupants. The enhancements have been the most prominent in the area of sensing, be it the sensing and characterization of the crash itself, or the sensing and characterization of occupants in the vehicle.

We propose a composite thermal model of the vehicle passenger compartment that can be used to predict and analyze thermal comfort of the occupants of a vehicle. Physical model is developed using heat flow in and out of the passenger compartment space, comprised of glasses, roof, seats, dashboard, etc. Use of a model under a wide variety of test conditions have shown high sensitivity of compartment air temperature to changes in the outside air temperature, solar heat load, temperature and mass flow of duct outlet air from the climate control system of a vehicle. Use of this model has subsequently reduced empiricism and extensive experimental tests for design and tuning of the automatic climate control system. Simulation of the model allowed several changes to the designs well before the prototype hardware is available.

The causes for 131 fatal crashes of lap-shoulder belted occupants were analyzed for crash causation and avoidance opportunities. Fourteen crash scenarios were determined to depict the situation and circumstance of the accidents. Each scenario is discussed in relation to driver age, actions, behavior, errors and aggressiveness, as well as crash type and other factors influencing the crash. Nearly a third of crashes involved a rapid, unpredictable onset by reckless action or mistake of another driver. The remainder were caused by the driver of the case-vehicle. Some were single vehicle crashes primarily related to excessive speed, aggressive driving, and drifting out of lane. The others were multi-vehicle crashes due primarily to inadvertent errors. The most common errors were right-of-way violations at an intersection, loss of control on wet roads, impact of a stationary vehicle, and lane changing errors.

Many traffic collisions are the result of the driver's failure to notice the other vehicle. It is often cited in police reports that the driver "looked but did not see.'' The purpose of Daytime Running Lights (DRLs) is to increase the visual contrast of DRL-equipped vehicles. Visual contrast, which is the difference in brightness between two areas, is an important characteristic enabling a driver to detect objects. This paper begins with a brief regulatory history of DRLs in the U.S. and how General Motors Corporation (GM) introduced DRL-equipped vehicles. It also describes a DRL effectiveness study conducted by Exponent Failure Analysis Associates of San Francisco for General Motors Corporation. The study compared the collision rates of specific General Motors Corporation, Saab, Volvo and Volkswagen vehicles before and immediately after the introduction of DRLs. Since DRLs are not visible from behind a vehicle, rear-end collisions were not included in the study.

Truck driver eye and head position tools have been developed to describe where certain percentages of truck drivers position there eyes and heads in various workspace arrangements. Separate equations describe the accommodation level for driver populations with male to female ratios of 50/50, 75/25, and a range from 90/10 to 95/5. These equations can be used as a design tool to locate the curves in vehicle space to describe the region behind which the given populations eyes and heads would be located. Equations and curves are provided for both the drivers eye and head in the side view. It has become increasingly apparent that there is a need for improved methods of accommodating truck drivers in heavy truck cab design. Currently, practices used in the automobile industry for passenger car design are utilized for the design of heavy trucks. These practices.

Truck driver shin-knee and stomach postion tools have been developed to describe where certain percentages of truck drivers position there knees and stomachs in various workspace arrangements. Separate equations describe the accommodation level for driver populations with male to female ratios of 50/50, 75/25, and a range from 90/10 to 95/5. These equations can be used as a design tool to locate the curves in vehicle space to describe the region behind which the given populations shin-knees, and stomachs would be located. Equations and curves are provided for both the left leg, which operates the clutch, and the right leg, which operates the accelerator.

A deformable finite element dummy model was used to simulate air bag interaction with in-position passenger side occupants in frontal vehicle crash. This dummy model closely simulates the Hybrid III hardware with respect to geometry, mass, and material properties. Test data was used to evaluate the validity of the model. The calculated femur loads, chest acceleration and head acceleration were in good agreement with the test data. A semi-rigid dummy model (with rigid chest) was derived from the deformable dummy to improve turnaround time. Simulation results using the semi-rigid dummy model were also in reasonable agreement with the test data. For comparison purpose, simulations were also performed using PAMCVS, a hybrid code which couples the finite element code PAMCRASH with the rigid body occupant code. The deformable dummy model predicted better chest acceleration than the other two models.

Fatal crash circumstances for 48 belted female drivers were studied in-depth and compared to those of 83 belted male drivers in a similar population of vehicles. Women had a higher incidence of crashes on slippery roads, during lane changes and passing maneuvers than men who had a higher rate of aggressive driving and speed related crashes (χ2 = 10.47, p < 0.001). Driver-side damage was significantly more frequent in female than male crashes (χ2 = 5.74, p < 0.025) and women had a higher fraction of side impacts (45.9% v 31.4%) and crashes during daylight (87.0% v 72.3%, χ2 = 3.65, p < 0.05) than men. Women also had a higher fraction of potentially avoidable crashes than men (57.5% v 39.0%) and a lower involvement related to aggressive driving (10.6% v 25.6%). These differences were statistically significant (χ2 = 5.41, p < 0.025).

This paper presents a new computerized approach for designing the automobile window glass contour, the glass drop motion, and the regulator systems. The three-dimensional geometrical relationship of the glass contour, the drop path, and its guidance system have been studied. Methods for barrel and helical drops are presented for optimizing the glass profile and drop path trajectories. Criteria for perfecting the glass contour are developed for shaping the profile of the vehicle clay model. Methods for correcting the glass contour and shape are presented. Examples are provided to illustrate how to improve the design. This approach integrates the development works of glass contour, drop motion and regulator systems. Through this design approach the window glass can fit and move perfectly in the door assembly.

The overall highway fatality rate has dropped almost contintinously since 1925, from 20 to 2.5 per hundred million miles of travel in 1984. Still, the almost 44, 000 fatalities in 1984 can, and will, be decreased. In 1983, 5, 475 of the 42, 584 highway fatalities were in accidents involving medium or heavy trucks. Only 18% of these were occupants of the trucks themselves. 82% were pedestrians or occupants of the “other vehicle.” The greatest number of combination truck accidents take place on two-lane rural roads. Single-vehicle accidents are responsible for 70% of heavy truck occupant fatalities. Doubles and heavier trucks appear to be as safe as other heavy trucks. Rollover and ejection are responsible for the greatest number of truck occupant fatalities.

The overall highway fatality rate has dropped almost continuously since 1925, from 20 to 2.5 per 100 million miles of travel in 1984. Still, the almost 44,000 fatalities in 1984 can and will be decreased. In 1983, 5,475 of the 42,584 highway fatalities were in accidents involving medium or heavy trucks. Only 18 percent of these were occupants of the trucks themselves; 82 percent were pedestrians or occupants of the other vehicle. The greatest number of combination truck accidents takes place on two-lane rural roads. Single-vehicle accidents are responsible for 70 percent of heavy truck occupant fatalities. Doubles and heavier trucks appear to be as safe as other heavy trucks. Rollover and ejection are responsible for the greatest number of truck occupant fatalities. When asked about her top priority as the new Secretary of Transportation, Mrs. Dole replied, “There's no higher mandate for the Department than to promote safety….”