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This SAE Information Report establishes performance requirements for devices used to warm diesel fuel before entering the fuel filter(s).

This SAE Standard specifies a stationary test method for determining and documenting the masking effect caused by parts of the base machine with equipment as specified by the manufacturer within a visibility test circle around the eye position of a seated operator. It applies to earthmoving machinery which has a specific seated operator’s position.

This SAE Standard specifies a stationary test method for determining the masking effect caused by parts of the base machine with equipment as specified by the manufacturer on a visibility test circle around the machine from the eye position point of a seated operator. It specifies a method for evaluating the maskings that may be present. It applies to earthmoving machines which have a specific operator’s station. It does not consider evaluation of maskings which may be present with operational movement of working tools.

This SAE Standard covers the minimum requirements for nonmetallic tubing as manufactured for use in gasoline or diesel fuel systems. It is not intended to cover tubing for any portion of the system which operates below -40 degrees C, above 115 degrees C, or above a maximum working gage pressure of 690 kPa.

The objective of this research was to further elucidate the biomechanical etiology of pelvis fracture under simulated automotive side impact conditions. The finite element (FE) method was used to evaluate pelvis fracture tolerance through a series of parametric tests to determine the effect of both force magnitude and duration of application. The results of FE analyses were compared to previous experimental cadaveric test data under the same load conditions to seek validation of the model. The hemi-pelvis FE model used in this study was a modified version of an earlier model, consisting of 2199 elements and 3161 nodes. Material behavior was defined per element using 524 Hookean-based material property values. Parametric dynamic analyses of the model were performed using the first 150 ms of the force-time history. Dynamic loading was applied as a linear ramp through the angle of the greater trochanter to the acetabulum, simulating a femur position in 90° flexion.

This study showed that subfracture impact loading to a joint creates stresses in cartilage and bone which can initiate a chronic osteoarthrosis. The magnitude and location of the impact induced stresses are dependent on the orientation and the intensity of loading. Impact loading produced lesions on retro-patellar cartilage and their depths increased as the thickness of subchondral bone increased with time post-impact. Mechanical tests of cartilage indicated significant softening twelve months post-impact. These alterations are similar to those documented clinically as early OA. In vitro impacts of isolated limbs, together with mathematical models, showed that high mean stress generated during impact may help protect joint tissues from acute injury. This study and others are being used to develop stress-based tissue failure criteria for predicting an osteoarthrosis following subfracture impact loading.

The mechanisms of knee fracture were studied experimentally using cadaveric knees and analytically by computer simulation. Ten 90 degree flexed knees were impacted frontally by a 20 kg pendulum with a rigid surface, a 450 psi (3.103 MPa) crush strength and a 100 psi (0.689 MPa) crush strength aluminum honeycomb padding and a 50 psi (0.345 MPa) crush strength paper honeycomb padding at a velocity of about five m/s. During rigid surface impact, a patella fracture and a split condylar fracture were observed. The split condylar fracture was generated by the patella pushing the condyles apart, based on a finite element model using the maximum principal stress as the injury criterion. In the case of the 450 psi aluminum honeycomb padding, the split condylar fracture still occurred, but no patella fractures were observed because the honeycomb provided a more uniform distribution of patella load. No bony fractures in the knee area occurred for impacts with a 50 psi paper honeycomb padding.

Numerous cadaver tests have been performed in the past to define the behaviour and tolerance of the thorax under side impact conditions. To take into account the various test conditions and measurements techniques or parameters, a lumped parameter model is used to reproduce these tests and thus to compute the protection criteria in the same way. The correlation between the calculated criteria and the observed injuries is then analysed as a basis for discussion of their consistency and relevance. The second part of the paper deals with the transposition of tolerance criteria to the Eurosid 1 dummy, using simulation tests under different conditions (impactor test, free-fall test, imposed velocity). The results show that this transposition depends on the test conditions, because of the limited biofidelity of the Eurosid 1 dummy.

It is well known that the ability of the human body to withstand trauma is a function of its inherent strength, i.e., the strength of the bones and soft tissues. Yet, the properties of the bones and tissues change as a function of the individual's age. In this paper age effects on thoracic injury tolerances are studied by analyzing the mechanical properties of human bones and soft tissues and by examining experimental results found in the literature of thoracic impact tests to human cadavers. This work suggests that the adult age range can be divided into three age groups. Using piece-wise linear regression analyses, it has been determined that the reduction in injury tolerance from the “young” age group to the “elderly” group is approximately 20% under blunt frontal impact loading conditions and is as much as 70% under belt loading conditions.

Axial loading of the calcaneus-talus-tibia complex is an important injury mechanism for moderate and severe vehicular foot-ankle trauma. To develop a more definitive and quantitative relationship between biomechanical parameters such as specimen age, axial force, and injury, dynamic axial impact tests to isolated lower legs were conducted at the Medical College of Wisconsin (MCW). Twenty-six intact adult lower legs excised from unembalmed human cadavers were tested under dynamic loading using a mini-sled pendulum device. The specimens were prepared, pretest radiographs were taken, and input impact and output forces together with the pathology were obtained using load cell data. Input impact forces always exceeded the forces recorded at the distal end of the preparation. The fracture forces ranged from 4.3 to 11.4 kN.

This work describes the development of a three-dimensional finite element model of the human ankle/foot complex. This model depicts the primary elements of a 50th percentile human ankle. It includes all the bones of the foot up to the distal tibia/fibula. It also contains the soft tissues of the plantar surface of the foot along with most of the ankle joint ligaments and retinacula. To calibrate the model, a plate with various initial velocities of 5, 7.5 and 10 mph is impacted at the plantar surface of the foot. The model is strictly stabilized by the intrinsic anatomical geometry and the ligamentous structure. It demonstrates to a great extent its capacity to replicate the dynamic response. Global responses of output acceleration and force time histories are obtained and compared reasonably well with experimental data.

The anatomical dimensions, inertial properties, and mechanical responses of cadaver leg, foot, and ankle specimens were evaluated relative to those of human volunteers and current anthropometric test devices. Dummy designs tested included the Hybrid III, Hybrid III with soft joint stops, ALEX I, and the GM/FTSS lower limbs. Static and dynamic tests of the leg, foot, and ankle were conducted at the laboratories of the Renault Biomedical Research Department and the University of Virginia. The inertial and geometric properties of the dummy lower limbs were measured and compared with cadaver properties and published volunteer values. Compression tests of the leg were performed using static and dynamic loading to determine compliance of the foot and ankle. Quasi-static rotational properties for dorsiflexion and inversion/eversion motion were obtained for the dummy, cadaver, and volunteer joints of the hindfoot.

In the present investigation, a numerical model of side impact dummy (DOT-SID) is developed using TNO's MADYMO-3D multi-body features. During the model construction phases, relevant dummy components are individually modeled and are verified against empirical test results. The completed DOT-SID model is then integrated into a padded impactor model to simulate secondary-impact. Computations are run for several input force-deflection distributions, in conjunction with other parameters. From the results, occupant responses to various thoracic input are quantitatively sought, and the effectiveness of the MADYMO DOT-SID model as a vehicle development tool is assessed.

A hybrid mathematical model of a prototype baseline vehicle including dummies and side impact barriers were used to evaluate the effect of vehicle modifications on injury response. Models of the EUROSID-1 and US-SID dummies, and a model of the human body were included in the vehicle model. Models of the EEVC foam and NHTSA honeycomb side impact barriers were used as impacting object. The vehicle model was impacted at 15 mph (24 km/h), 25 mph (40 km/h) and 35 mph (56 km/h) by the barriers. The occupant responses of vehicle modifications were evaluated. At 15 mph (24 km/h) barrier impact velocity, no reductions in the injury criteria were obtained with padding. At 25 mph (40 km/h) and 35 mph (56 km/h) barrier impact velocity, however, reductions in the injury criteria were obtained with padding. The impact with the EEVC barrier was found to be more violent for the occupant than the impact with the NHTSA barrier; thus, higher dummy responses were obtained with the EEVC barrier.

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.

A modeling technique was developed to simulate the door/occupant interaction in the FMVSS 214 test. The door components, including all the panels and the side airbag, were modeled by finite elements and the Side Impact Dummy was modeled by rigid segments with finite element contact surfaces. The DYNA3D finite element code and the CAL3D lumped-mass code were coupled together such that features in each program can be utilized in this modeling approach. A numerical scheme was developed to simulate the door crush due to the barrier impact to obtain the proper door interior stiffness. Material constants for the model were derived from the available test data. The model exhibited good correlation with the barrier test data for the dummy acceleration response. Using this model, potential countermeasures, including thorax padding, an armrest design, and a side airbag, were evaluated.

The Finite Element predictions of the physical response of foams during impact by a rigid body (such as, the Hybrid III head form) is determined by material law equations generally approximated based on the theory of elastoplasticity. However, the structural aspect of foam, its discontinuous nature, makes it difficult to apply the laws of continuum mechanics and construct constitutive equations for foam-like material. One part of the problem relates to the state of stress. In materials such as steel, the state of hydrostatic stress does not affect the stress strain behavior under uniaxial compression or tension in plastic regime. In other words, when steel is subject to hydrostatic pressures the stress strain characteristic can be predicted from a uniaxial test. However, if the stresses acting on a section of foam are triaxial, the response of a head-form may be different than predicted from uniaxial test data.

Automotive collision data from the National Accident Sampling System database (compiled by the National Highway Traffic Safety Administration) was analyzed in regard to occupants who sustained major pelvic injuries during 1980-1992. These injuries included pelvic fracture, pelvic dislocation, pelvic separation, pelvic crush, and pelvic fracture/dislocation. All collisions analyzed were required to have a computed change in velocity during the collision, as well as data concerning injuries sustained by the occupants. The purpose of this research was to retrospectively analyze motor vehicle crash data to establish incidence of major pelvic injuries within automotive collisions. From the study, 1.8% of all collisions evaluated resulted in major pelvic injuries. Twenty-two percent of all crashes were side impact collisions and 8% of these side impact collisions resulted in occupants sustaining major pelvic injuries.

A humerus provisional reference value (PRV) based on human surrogate data was developed to help evaluate upper arm injury potential. The proposed PRV is based on humerus bone bending moments generated by testing pairs of cadaver arms to fracture in three-point bending on an Instron testing machine in either lateral-medial (L-M) or anterior-posterior (A-P) loading, at 218 mm/s and 0.635 mm/s loading rates. The results were then normalized and scaled to 50th and 5th percentile sized occupants. The normalized average L-M bending moment at failure test result was 6 percent more than the normalized average A-P bending moment. The normalized average L-M shear force at failure was 23 percent higher than the normalized average A-P shear force. The faster rate of loading resulted in a higher average bending moment overall - 8 percent in the L-M and 14 percent in the A-P loading directions.

This study utilizes a unique database that allows for the calculation of the correlation of injuries to child passengers involved in motor vehicle accidents with the restraint system and the accident characteristics. The database contains 4600 records of accidents involving children age 12 and under that occurred in 13 counties in western New York State during 1991 and 1992. Injured subjects and non-injured subjects were selected from data provided by the New York State Department of Motor Vehicles identifying reported accidents involving the target population in the time period and geographical area defined. The data sources included police accident reports, emergency medical team reports, hospital records and contact with the parents of children who were in child restraints. In child restraint cases, the type of child restraint in use is identified and misuse or equipment failure is noted.