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Standing reach envelopes are important tools for the design of industrial and vehicle environments. Previous work in this area has focussed on manikin-based (where a few manikins are used to simulate individuals reaching within the region of interest) and population-based (where data are gathered on many individuals reaching in a constrained environment) approaches. Each of these methods has merits and shortfalls. The current work bridges the manikin- and population-based approaches to assessing reach by creating population models using kinematic simulation techniques driven by anthropometric data. The approach takes into account body dimensions, balance, and postural cost to create continuous models that can be used to assess designs with respect to both maximal and submaximal reaches. Cost is quantified as the degree to which the torso is involved in the reach, since the inclination of the torso is a good measure of lower-back load and may be related to subjective reach difficulty.

This paper describes control system and psychological concepts enabling the development of a simulation model suitable for use in emulating driver performance in situations involving the longitudinal control of the distance and headway-time to a preceding vehicle. The developed model has mathematical expressions and relationships pertaining to the driver's skill in operating the brake and accelerator (“inverse dynamics”) and the driver's perceptual and decision-making capabilities (“desired dynamics”). Simulation results for driving situations involving braking and accelerating are presented to aid in understanding the research work.

The UMTRI Airbag Skin Burn Model has been improved through laboratory testing and the implementation of a more flexible heat transfer model. A new impinging jet module based on laboratory measurements of heat flux due to high-velocity gas jets has been added, along with an implicit finite-difference skin conduction module. The new model can be used with airbag gas dynamics simulation outputs, or with heat flux data measured in the laboratory, to predict the potential for thermal skin burn due to exposure to airbag exhaust gas.

Two new techniques for investigating the thermal skin-burn potential of airbags are presented. A reduced-volume airbag test procedure has been developed to obtain airbag pressures that are representative of a dynamic ridedown event during a static deployment. Temperature and heat flux measurements made with this procedure can be used to predict airbag thermal burn potential. Measurements from the reduced-volume procedure are complemented by data obtained using two gas-jet simulators, called heatguns. Gas is vented in controlled bursts from a large, heated, pressurized tank of gas onto a target surface. Heat flux measurements on the target surface have been used to develop quantitative models of the relationships between gas jet characteristics and burn potential.

This paper describes an ongoing effort to develop computer-simulated instrumentation for the UMTRI Driver Interface Research Simulator. The speedometer, tachometer, engine and fuel gauges, along with warning lights are back projected onto a screen in front of the driver. The image is generated by a Macintosh running LabVIEW. Simulated instrumentation (instead of a production cluster) was provided so that new display designs can be rapidly generated and tested. This paper addresses the requirements for prototyping software, the advantages and disadvantages of the packages available, and the UMTRI implementation of the software, and its incorporation into the driving simulator.

An appropriately contoured lumbar support is widely regarded as an essential component of a comfortable auto seat. A frequently stated objective for a lumbar support is to maintain the sitter's lumbar spine in a slightly extended, or lordotic, posture. Although sitters have been observed to sit with substantial lordosis in some short-duration testing, long-term postural interaction with a lumbar support has not been documented quantitatively in the automotive environment. A laboratory study was conducted to investigate driver posture with three seatback contours. Subjects† from four anthropometric groups operated an interactive laboratory driving simulator for one-hour trials. Posture data were collected by means of a sonic digitizing system. The data identify driver-selected postures over time for three lumbar support contours. An increase of 25 mm in the lumbar support prominence from a flat contour did not substantially change lumbar spine posture.

Although driver-side airbag systems provide protection against serious head and chest injuries in frontal impacts, injuries produced by the airbag itself have also been reported. Most of these injuries are relatively minor, and consist primarily of skin abrasions and burns. Previous investigations have addressed the mechanisms of airbag-induced skin abrasion. In the current research, laboratory studies related to the potential for thermal burns due to high-temperature airbag exhaust gas were conducted. A laboratory apparatus was constructed to produce a 10-mm-diameter jet of hot air that was directed onto the leg skin of human volunteers in time-controlled pulses. Skin burns were produced in 70 of 183 exposures conducted using air temperatures ranging from 350 to 550°C, air velocities from 50 to 90 m/s, and exposure durations from 50 to 300 ms.

The road damage caused by heavy trucks is accentuated by the dynamic loads excited by roughness in the road. Simulation models of trucks are used to predict dynamic wheel loads, but special models are required for tandem suspensions. Parameter values to characterize tandem suspension systems can be measured quasi-statically on a suspension measurement facility, but it is not known how well they fit dynamic models. The dynamic behavior of leaf-spring and air-spring tandem suspensions were measured on a hydraulic road simulator using remote parameter characterization techniques. The road simulator tests were duplicated with computer simulations of these suspensions based on quasi-static parameter measurements to compare dynamic load performance. In the case of the walking-beam suspension, simulated performance on the road was compared to experimental test data to evaluate the ability of the walking-beam model to predict dynamic load.

In recent investigations of airbag deployments, drivers h v c reported abrasions to the face, neck, and forearms due to deploying airbags, A study of the airbag design and deployments parameters affecting the incidence and severity of abrasions caused by driver-side airbags has led to the development of a laboratory test procedure to evaluate the potential of an airbag design m cause skin injury This report describes the procedure, which is based an static deployments of airbags into a cylindrical lest fixture. The target area is covered with a material that responds to abrasion-producing events in a manner related to human skin tolerance. Test results show excellent correlation with abrasion injuries produced by airbag deployments into the skin of human volunteers.

This paper describes the methodology and results from a project involving development of anthropometrically based design specifications for a family of advanced adult anthropomorphic dummies. Selection of family members and anthropometric criteria for subject sample selection were based on expected applications of the devices and on an analysis of U.S. population survey data. This resulted in collection of data for dummy sizes including a small female, a mid-sized male, and a large male. The three phases of data collection included: 1. in-vehicle measurements to determine seat track position and seating posture preferred by the subjects for use in development of laboratory seat bucks; 2. measurement of subject/seat interface contours for fabrication of an average hard seat surface for use in the buck; and 3. measurement of standard anthropometry, seated anthropometry (in the buck), and three-dimensional surface landmark coordinates using standard and photogrammetric techniques.