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Experimentally derived brain response envelopes are needed to evaluate and validate existing finite element (FE) head models. Motion of the brain relative to the skull during rotational input was measured using high-speed biplane x-ray. To generate repeatable, reproducible, and scalable data, methods were developed to reduce experimental variance. An “extreme-energy” device was developed to provide a controlled input that is unaffected by specimen characteristics. Additionally, a stereotactic frame was used to deploy radiopaque markers at specific, pre-determined locations within the brain. One post-mortem human surrogate (PMHS) head specimen was subjected to repeat tests of a half-sine rotational speed pulse in the sagittal plane. The desired pulse had a peak angular speed of 40 rad/s and duration of 30 ms. Relative motion of the brain was quantified using radiopaque targets and high-speed biplane x-ray. Frontal and occipital intracranial pressure (ICP) were also measured.

Recently, the global increase of elderly vehicle users has become an issue to be considered in the effort of enhancing safety performance of vehicle restraint system. It is thought that an evaluation tool for the system representing properties of age-specific human body will play a major role for that. In previous research, the authors had developed age-specific component finite element (FE) models for the lower limb, lumbar spine, and thorax representing the adult and elderly occupants. However, the models have not been validated in terms of full body kinematics. It is essential for such models to be validated in terms of full body kinematics in order to ensure validity of the results of the assessment of the safety performance of restraint systems. In the present research, the adult and elderly occupant full body FE models were developed by incorporating the lower limb, lumbar spine and thorax of the adult and elderly FE models established in previous research.

Kinematics and Compliance (K&C) testing is used to evaluate the ride and handling performance of an automobile. During a typical K&C test, the vehicle body is fixed while controlled forces or displacements are applied to the wheels. The results of the test include vehicle suspension parameters, such as toe, camber, etc. Numerical simulations of this test are usually performed using multibody dynamics software that introduces simplifying rigid body assumptions. However, the need for component flexibility in K&C simulation is increasing along with demand for more precise suspension system designs. In this paper, a new methodology for K&C simulation is proposed using Abaqus. First, rigid body suspension mechanism analyses are performed using Abaqus and Adams, and the results are compared. Then a nonlinear Abaqus finite element model, with flexible suspension components and vehicle body, is analyzed and the results are compared with the rigid body suspension analyses.

This paper deals with the development of a 3.5 tonne carrying double wishbone front suspension for a low floor LCV. It is a novelty in this class of vehicles. It has a track width of 1810 mm and it has a recirculating ball steering system. The steering mechanism has been arranged so that the steering angle could reach to 48° that is a very effective angle in that vehicle range. This results as a lower turning radius which indicates a better handling for the vehicle. The steering and the front suspension system here have been optimized in terms of comfort and handling by using DOE (design of experiments) based on sequential programming technique. In order to achieve better suspension and steering system geometry, this technique has been applied. The results have been compared with the benchmark vehicle.

For concept and design of modern suspension systems many different demands have to be considered. Beside package and lightweight construction especially the real scopes of a suspension system, kinematics and compliance, are getting more and more important to fulfill all technical needs coming from the automotive market. In particular the development of suspension systems for Sports Utility Vehicles (SUVs) has to satisfy very high demands and strong characteristics criteria coming from the On-Road and Off-Road driving. As many different load cases have to be taken into account, an analytic approach can only be used for first concept steps to design a SUV-suspension system. After that it is necessary to verify and tune all suspension and bushing characteristics by the use of multibody simulation tools like e. g. ADAMS. Therefore adequate models of all suspension components have to be available [6].

This study focused on a better understanding and characterization of the submarining phenomenon that occurs in frontal crashes when the lap belt slides over the anterior superior iliac spine. Submarining is the consequence of the pelvis kinematics relative to the lap belt, driven by the equilibrium of forces and moments applied to the pelvis. The study had two primary purposes; the first was to provide new PMHS data in submarining test configurations, the second was to investigate the Hybrid II and Hybrid III dummies biofidelity regarding submarining. Several Post Mortem Human Subject (PMHS) studies have been published on this subject. However, the lack of information about the occupant initial positioning and the use of car seats make it difficult to reconstruct these tests. Furthermore, the two dummies are rarely compared to PMHS in submarining test configurations. A fifteen frontal sled test campaign was carried out on two Anthropomorphic Test Devices (ATDs) and nine PMHS.

The paper describes the kinematic analysis of the cam/follower contact in a valve gear design in which the valve is operated by a centrally pivoted follower. A novel feature of the analysis is that velocities are determined from the valve lift curve rather than the cam profile. The entraining velocity at the cam/follower contact has been obtained and the variation of elastohydrodynamic film thickness over the operating cycle has been calculated.

The purposes of this study were to measure the relative linear and angular displacements of each pair of adjacent cervical vertebrae and to compute changes in distance between two adjacent facet joint landmarks during low posterior- anterior (+Gx) acceleration without significant hyperextension of the head. A total of twenty-six low speed rear-end impacts were conducted using six postmortem human specimens. Each cadaver was instrumented with two to three neck targets embedded in each cervical vertebra and nine accelerometers on the head. Sequential x-ray images were collected and analyzed. Two seatback orientations were studied. In the global coordinate system, the head, the cervical vertebrae, and the first or second thoracic vertebra (T1 or T2) were in extension during rear-end impacts. The head showed less extension in comparison with the cervical spine.

This paper contains an analysis and a related numerical method for finding the movement of a wheel mounted on a double A-Arm suspension. The method is based on the use of Euler orientation variables similar to those which specify aircraft orientations in flight-dynamics studies.

High-speed biplane x-ray was used to investigate relative kinematics of the thoracoabdominal organs in response to blunt loading. Four post-mortem human surrogates instrumented with radiopaque markers were subjected to eight crash-specific loading scenarios, including frontal chest and abdominal impacts, as well as driver-shoulder seatbelt loading. Testing was conducted with each surrogate perfused, ventilated, and positioned in an inverted, fixed-back configuration. Displacement of radiopaque markers recorded with high-speed x-ray in two perspectives was tracked using motion analysis software and projected into calibrated three-dimensional coordinates. Internal organ kinematics in response to blunt impact were quantified for the pericardium, lungs, diaphragm, liver, spleen, stomach, mesentery, and bony structures.

A gap in protection appears to exist for older children who have outgrown booster seats and are placed in some adult, 3-point belts with fixed shoulder belt anchorage points. Boys on average do not reach the 50th percentile adult, male seated height until age 15 ½ and the average girl never reaches this height. The published minimum seated height and weight thresholds for use of three-point belts alone are inconsistent with the official recommendations by The National Transportation Safety Board and the majority of state seat belt laws. A shoulder belt with a fixed upper anchorage, which is typical in the rear occupant space, may create torso belt routing that can allow rollout from the shoulder belt in frontal oblique collisions. A belt trajectory that passes across the neck of an older child may create an artificial fulcrum in the cervical spine resulting in quadriplegia. Excessive webbing lengths can promote child occupant excursion, rebound and injurious head contact.

The catalytic conversions of diesel exhausting particulates (DEP) are studied in this paper. The oxidation catalysts, carried by Y-Al,O, pellets, are prepared with the method of impregnation. By use of thermo-gravimetric analysis (TGA) technique, the catalytic abilities of these catalysts are studied and the igniting characteristics of DEP are determined. A mathematical method is introduced to process TGA experimental data furtherly. Some equations have been derived to evaluate the kinetic parameters of the oxidation reaction of DEP. By comparing the activation energy (Ea) of the reaction and the igniting temperature (Ti) of DEP, the catalytic activities of the oxidation catalysts are evaluated.

In order to control the formation of particulate carbon during diesel combustion it is important to understand the mechanisms and kinetics of formation. This report addresses several aspects of diesel soot formation, focusing primarily on the influence of coagulation processes on the spherule size and kinetics of formation. Our previously developed nucleation/depletion model for the spherule size of particulate carbon has been modified to take account of coalescent coagulation during the early stages of diesel soot formation. Such coagulation should not increase spherule size by more than a factor of two or three. Simple coagulation theory has been employed to calculate the time constants for coalescent and chain-forming coagulation. Kinetics aspects of other processes --nucleation, particle fusion, dehydrogenation, depletion of precursors, and oxidation --have also been assessed.

To assist automotive seat development and evaluation, a technique for predicting the posture of seated occupants has been developed. The method involved modeling the torso geometry and articulation of a mid-size male, based on information presented in SAE paper number 930110 [1]. This mid-size male model, known as 2-D JOHN, was developed in a commercial kinetic modeling software and used in a comparative seat evaluation study between a current production automotive seat and a prototype articulating seat. The 2-D JOHN model was supported a greater range of postures, defined as Total Lumbar Curvature (TLC) and Torso Recline Angle (TRA), in the prototype seat than the automotive seat.

The various forms of professional and amateur motor sports all require barriers, fences and deceleration/run-off areas for driver and spectator safety. We examine the translational and rotational kinetic energies involved for various types of race vehicles, and present some comparisons to typical energies encountered in everyday situations. Stopping distance vs. deceleration rates are also calculated, and some simplified trajectory analyses are performed for parts potentially launched during racing accidents.

Impact characteristics of aluminum wheels are evaluated in accordance to the testing procedure SAE J175. In an effort to simplify the numerical modeling of wheel impact testing, numerical analysis has been conducted to investigate the percentage of the striker kinetic energy absorbed by the tire during the impact test. 10%, 15%, 20%, 25%, and 30% reductions of the striker kinetic energy were computed in order to assess the appropriate percentage reduction. Comparisons of wheel plastic deformations of both experimental and numerical methods illustrate that a 20% reduction in the striker kinetic energy provides an effective approach to simplify the modeling.

Normally, the energy conversion efficiency in road vehicle was presented in term of amount of unit fuel per distance within specific condition where it could not be comparable in practice that the variations of dynamic traffic condition and driver behavior were impacted. To minimized energy consumption, the both traffic conditions and driver behavior needs to be managed. The traffic conditions improves as infrastructure development, but the driver behavior needs personal training with equipment In this study, the alternative practical indicator was proposed with applying specific positive kinetic energy concept to indicate the level of vehicle dynamic behavior which relate to the level of fuel consumption rate. Furthermore, the experimental were taken place in Pahonyothin Rd. (Bangkok, Thailand) including urban, sub-urban and highway with various traffic congestion level.

This paper considers the need for improving urban transportation and the proposed air quality plans that have been recently announced by the Environmental Protection Agency for several of the more populated regional basins. The “transit diversion mandate” (the need for diversion of a considerable portion of urban travel from the automobile to public transit) is discussed. One proposed diversionary approach, the rubber-tired trolley coach, with its quiet, reliable, and pollution-free characteristics and an advanced LMSC kinetic energy flywheel which can be used to broaden considerably the capabilities of the trolley coach are described.

This paper presents total kinetic energy and dissipation rate spectra calculated from particle image velocimetry (PIV) measurements in a motored, spark-ignition direct-injection (SIDI) engine. Velocity fields were obtained at two engine speeds and swirl conditions in the second half of the compression stroke. Two magnifications were used to achieve a spatial dynamic range covering from the full cross-section of the flat piston window (∼45 mm) down to 350 μm. Sets of 300 instantaneous vector fields were filtered using a Gaussian filter to isolate flow structures over a range of length-scales. The kinetic energy and dissipation rate spectra have been normalized using mean kinetic energy and mean piston speed. Results indicate that if the mean piston speed is selected as the representative outer variable, the kinetic energy and dissipation rate spectra at 2000 RPM and 600 RPM become self-similar over a portion of the spectra regardless of swirl level.

To meet the strict emission regulations for diesel engines, an advanced processing device such as a Urea-SCR (selective catalytic reduction) system is used to reduce NOx emissions. The Real Driving Emissions (RDE) test, which is implemented in the European Union, will expand the range of conditions under which the engine has to operate [1], which will lead to the construction of a Urea-SCR system capable of reducing NOx emissions at lower and higher temperature conditions, and at higher space velocity conditions than existing systems. Simulations are useful in improving the performance of the urea-SCR system. However, it is necessary to construct a reliable NOx reduction model to use for system design, which covers the expanded engine operation conditions. In the urea-SCR system, the mechanism of ammonia (NH3) formation from injected aqueous urea solution is not clear. Thus, it is important to clarify this mechanism to improve the NOx reduction model.