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The objective of the study was to document the thoracic deformation contours in a simulated frontal impact. Unembalmed human cadavers and the Hybrid III anthropomorphic manikins were tested. Data from the newly developed External Peripheral Instrument for Deformation Measurement (EPIDM) was used to derive deformation patterns at upper and lower thoracic levels. Deceleration sled tests were conducted on three-point belt restrained surrogates positioned in the driver's seat (no steering assembly) using a horizontal impact test sled at velocities of approximately 14.0 m/s. Lap and shoulder belt forces were recorded with seat belt transducers. The experimental protocol included a Hybrid III manikin experiment followed by the human cadaver test. Both surrogates were studied under similar input and instrumentation conditions, and identical data acquisition and analysis procedures were used. All six testedcadavers demonstrated multiple bilateral rib fractures.

This study presents a design concept for a multi-configuration modular medical evacuation fixture that can be used to retrofit standard utility vehicles for emergency medical transport. The fixture has been designed so that when installed in a vehicle and configured for litter transport, it provides mounting structure for a single patient on a North Atlantic Treaty Organisation (NATO) style litter as well as for a variety of emergency medical equipment. When installed in a vehicle and configured for ambulatory patient transport, the device provides safe seating for multiple patients as well as mounting surfaces for medical equipment. When not installed, the fixture can be collapsed for ease of shipping and warehousing. A survey of potential host vehicles was conducted to evaluate the feasibility of the proposed design. Given a preliminary concept, factors such as expected patient anthropometry, and physical data of medical equipment were used to perform basic structural analyses.

This paper investigates how reaching and grasping are affected by various object properties and conditions. While previous studies have examined the effect of object attributes such as size, shape, and distance from the subject, there is a need for quantitative models of finger motions. To accomplish this, the experiment was performed with six subjects where the 3D-coordinates of the finger joints and the wrist of one hand were recorded during reaching and grasping tasks. Finger joint angles at final posture were found to depend on both object size and orientation while wrist postures were changed primarily depending on object orientation. Also, each object orientation caused alteration in relative object location with respect to the hand at final posture. In addition, analysis of temporal variables revealed that it took from 1.06 to 1.30 seconds depending on the object distance to start reaching and complete grasping of the object.

The objective of this paper is to investigate the dynamic space envelope during reaching and grasping tasks. Some amount of space is required for the hand and arm to move without interference in reach-to-grasp tasks. The required space (‘dynamic space envelope’) has not been examined in spite of its importance. In this paper, we tested the hypothesis that the dynamic space envelope is a function of object size, hand size, grip type and distance. Six subjects (5 males, 1 female) participated in an experiment, in which they reached for and grasped three differently sized cylindrical objects (D: 26 mm, 60 mm, 114 mm) placed 40 cm in front of the subjects. Twenty-three markers were attached to the dorsal side of the hand and a 3-D motion capture system recorded the positions of the markers during reaching and grasping. The total distance from start to end positions is evenly divided into 10 ranges, and the areas of the required spaces were calculated for each range.

Determination of human tolerance to injury is difficult because of the physical differences between humans and animals, dummies and cadaver tissue. Certain human volunteer testing has been done but at subinjurious levels [STAP 86] [EWIN 72] Considerable biomechanical engineering injury studies exist for the adult human cadaver however little is available for the pediatric population [SANC 99] [KLEI 98b]. Studies have been made of pediatric skull bone modulus, fetal tendon and early pediatric studies of the newborn during delivery, however, a paucity of information still exists in these areas. A number of dummies have recently been made available principally for airbag testing to bridge the gap between the 50 percentile Hybrid III male dummy and the 95 percentile male dummy.

The Federal Motor Vehicle Safety Standard 571.201 discusses occupant protection with interior impacts of vehicles. Recent rule making by the National Highway Traffic Safety Administration (NHTSA) has identified padding for potential injury reduction in vehicles. Head injury mitigation with padding on vehicular roll bars was evaluated. After market 2 to 2.5 cm thick padding and metal air gap padding reduced the head injury criterion (HIC) and angular acceleration compared to the stock foam roll bar padding. Studies were conducted with free falling Hybrid 50% male head form drops on the fore head and side of the head. Compared to the stock roll bar material, a nearly 90% reduction in HIC was observed at speeds up to 5.4 m/s. A concomitant 83% reduction in angular acceleration was also observed with the metal air gap padding. A 2 to 2.5 cm thick Simpson roll bar padding produced a 70 to 75% reduction in HIC and a 59 to 73% reduction in angular acceleration.

Efficient methods for simulating operators performing part handling tasks in manufacturing plants are needed. The simulation of part handling motions is an important step towards the implementation of virtual manufacturing for the purpose of improving worker productivity and reducing injuries in the workplace. However, industrial assembly tasks are often complex and involve multiple interactions between workers and their environment. The purpose of this paper is to present a series of industrial simulations using the Human Motion Simulation Framework developed at the University of Michigan. Three automotive assembly operations spanning scenarios, such as small and large parts, tool use, walking, re-grasping, reaching inside a vehicle, etc. were selected.

Significantly, more fatalities and serious injuries occur due to ejection in roll over accidents. The present study was conducted to determine the occupant retention and head-neck injury potential aspects of laminated glass in roll over accidents. The head injury and neck parameters were obtained from Hybrid III 50% male dummy test device impacting on various types of side windows with laminated glass. Results indicated that the glass contained the dummy assembly and the head neck biomechanical parameters were below the critical value injury tolerance limits in simulated rollover accidents.

A 3-dimensional kinematic model for predicting grip posture was developed. The finger joints are all rotated at a constant rate until contact is detected between the fingers and the work object. By comparing the model’s predicted hand postures with experimental data, it was shown that the model gave reasonable predictions (R2=0.72). The model predicts MCP (Metacarpophalangeal) and PIP (Proximal Interphalangeal) joint angles better than it predicts DIP (Distal Interphalangeal) joint angles. A sensitivity study using this model was performed. The hand length, hand breadth, object size and skin deformation level were changed and the effects of these factors on hand posture was examined. The hand length, hand breadth and skin deformation level do not seem to affect hand posture much. But the change in object size affects hand posture much more than other factors.

The objective of the present study was to determine the biomechanics of the human thorax in a simulated frontal impact. Fourteen unembalmed human cadavers were subjected to deceleration sled tests at velocities of nine or 13 m/s. Air bag - knee bolster, air bag - lap belt, and air bag - three-point belt restraint systems were used with the specimen positioned in the driver's seat. Two chest bands were used to derive the deformation patterns at the upper and lower thoracic levels. Lap and shoulder belt forces were recorded with seatbelt transducers. After the test, specimens were evaluated using palpation, radiography, and a detailed autopsy. Thoracic trauma was graded according to the Abbreviated Injury Scale based on autopsy findings. Peak thoracic deformations were normalized with respect to the initial chest depth to facilitate comparison between the specimens.

The objective of the study was to investigate the biomechanical response of the intact cranium. Unembalmed human cadavers were used in the study. The specimens were transected at the base of the skull leaving the intracranial contents intact; x-ray and computed tomography (CT) scans were obtained. They were fixed in a specially designed frame at the auditory meatus level and placed on the platform of an electrohydraulic testing device via a six-axis load cell. Following radiography, quasistatic loading to failure was applied to one of the following sites: frontal, vertex, parietal, temporal, or occipital. Retroreflective targets were placed in two mutually orthogonal planes to record the localized temporal kinematics. Applied load and piston displacement, and the output generalized force (and moment) histories were recorded using a modular digital data acquisition system. After the test, x-ray and CT images were obtained, and defleshing was done.

Head injury is a serious threat to lives of people working around farm machinery. The consequence of head injuries are costly, paralytic, and often fatal. Clinical and biomechanical data on head injuries are reviewed and their application in the analysis of head injury risk associated with farm tractor discussed. A significant proportion of tractor-related injuries and deaths to adults, as well as children, is due directly or indirectly to head injury. An improved injury reporting program and biomechanical studies of human response to tractor rollover, runover, and falls, are needed to understand mechanisms of the associated head injury.

Sixty-three simulated frontal impacts using cadaveric specimens were performed to examine and quantify the performance of various contemporary automotive restraint systems. Test specimens were instrumented with accelerometers and chest bands to characterize their mechanical responses during the impact. The resulting thoracic injury severity was determined using detailed autopsy and was classified using the Abbreviated Injury Scale. The ability of various mechanical parameters and combinations of parameters to assess the observed injury severities was examined and resulted in the observation that belt restraint systems generally had higher injury rates than air bag restraint systems for the same level of mechanical responses. To provide better injury evaluations from observed mechanical parameters without prior knowledge of what restraint system was being used, a dichotomous process was developed.

The purpose of this study was to investigate the use of the chestband in side impact conditions by conducting validation experiments, and evaluating its feasibility by conducting a series of human cadaver tests under side impact crash scenarios. The chestband validation tests were conducted by wrapping the device around the thorax section of the Side Impact Dummy at its uppermost portion. The anthropomorphic test device was seated on a Teflon pad on a platform to accept impact from the side via a pendulum system. Tests were conducted at 4.5, 5.7, and 6.7 m/sec velocities using round and flat impactors. Retroreflective targets were placed at each strain gauge channel on the edge of the chestband. The test was documented using a high-speed digital video camera operating at 4500 frames/sec. Deformation contours and histories were obtained using the chestband electronic signals in combination with the RBAND-PC software.

Accurate data on the body dimensions of truck drivers are needed and such data are not presently available. This paper provides basic source data and an anthropometrical overview of the usefulness and limitations of existing data bases; discusses the influence of population factors, including age, sex, and demographic variables; and reviews population sampling problems. Heavy truck drivers as a whole appear to represent a physically different population from that of either the U.S. general population or other professional groups. Future anthropometric surveys must provide information for improved accommodation for the increasing range of physical size of users, and for obtaining data more useful to engineers involved in heavy truck interior cab design.

Empirical models are presented which predict the threespace position of the torso when responding to reaches with the right arm. Models were derived which specify torso position in terms of the spacial location of 10 surface markers. These markers were positioned over palpable skeletal points of the spine and shoulder girdle. The necessary data were obtained through photogrammetric procedures utilizing four orthogonal cameras. The independent (input) variables to these models are the coordinates of the reach target. A supplementary, slightly more accurate, set of models was also derived in which the set of independent variables was enlarged to include the anthropometric dimensions of the subject. The second, concurrent phase of the analysis resulted in the derivation of a set of models which describes the configuration of the internal, torso skeletal system.

The object of this study has been to develop a quantitative description of the mobility of the human torso, including the shoulder girdle, neck, thoracic and lumbar vertebral column, and pelvis. This has been accomplished by a systematic multidisciplinary investigation involving techniques of cadaver dissection and measurement, utilizing cineradiofluoroscopy for joint center of rotation location, anthropometry, radiography, and photogrammetry for selected positions and motions of living subjects, and computer analysis. Positional and dimensional data were obtained for 72 anthropometric dimensions on 28 living male subjects statistically representative of the 1967 USAF anthropometric survey of 3542 rated officers, including bone lengths of the extremities and vertebral landmarks. Normal excursion of these limbs was measured in the living, utilizing the landmarks established in initial cadaver dissection.

General aviation accident investigations can provide valuable data to the design engineer concerning the crash performance of current models and can indicate needed improvements for occupant protection in future aircraft. Current statistics and the historical background of major investigations during the past 65 years are provided. A five-year study of general aviation accidents occurring in the State of Michigan is used as a basis to illustrate recent findings relative to occupant injury mechanisms, relative crash protection, and crashworthiness performance of current models of aircraft. Results indicate that the degree of structural damage may not relate to the degree of occupant injury when the cabin area remains relatively intact. A primary requirement is documented for adequate upper-torso restraint for all occupants, and the excellent crash performance of such a system is described.

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.

Statistics indicate that during the past decade (1967-1976) the number of general aviation aircraft involved in an accident is equivalent to at least 38% of the total U.S. production during that period. Estimates that an aircraft will be involved in an accident over a 20 year life range are as high as 60-70%. Recognition of this probability has led to crashworthiness and occupant survivability “packaging” design concepts as offering the most realistic approach to reduction of serious and fatal injuries when an accident occurs. This paper reviews and illustrates current general aviation aircraft accident experience relative to occupant impact injury and damage indexes, and provides new data relative to current-generation aircraft.