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The objective of this investigation was to determine if the HVOSM accident simulation software could be used to model a vehicle with a modern McPherson strut type front (or rear) suspension system. HVOSM has previously been validated for simulation of double A-arm suspensions. To accomplish this task, kinematic models of both the McPherson strut and the double A-arm suspensions were evaluated using data from two vehicles with similar track width, wheel base and weight, but with the different suspension systems. The results of the study indicate the wheel track on a vehicle with a McPherson strut suspension system more closely follows the motions assumed in the development of the HVOSM models. Therefore, a user of HVOSM can utilize data from a vehicle with a McPherson strut suspension system and be confident the simulation is at least as accurate as if the vehicle had a double A-arm suspension.

The kinematic model of a generalized double-offset joint(DOJ) is presented. The relationship between the input and output angles of DOJ may be analyzed by solving the quartic equation for the angular displacement from the output shaft to the normal of the homokinetic plane. The sensitivities of the output angle are evaluated and the cause for the output angle error is investigated with the kinematic constants curves. A method is presented for simulating the relationship between the input and output angles in the case where there exist a clearances between an inner-race and the balls. Moreover, the relationship between the input and output angles of the actual DOJ and the deviation of the input axis relative to the output axis are precisely measured, and the case of the output angle error is investigated by the simulation the cause of output angle error.

Frontal impacts with reclined occupants are rare but severe, and they are anticipated to become more common with the introduction of vehicles with automated driving capabilities. Computational and physical human surrogates are needed to design and evaluate injury countermeasures for reclined occupants, but the validity of such surrogates in a reclined posture is unknown. Experiments with post-mortem human subjects (PMHS) in a recline posture are needed both to define biofidelity targets for other surrogates and to describe the biomechanical response of reclined occupants in restrained frontal impacts. The goal of this study was to evaluate the kinematic and injury response of reclined PMHS in 30 g, 50 km/h frontal sled tests. Five midsize adult male PMHS were tested. A simplified semi-rigid seat with an anti-submarining pan and a non-production three-point seatbelt (pre-tensioned, force-limited, seat-integrated) were used.

In order to have a windshield wiper system according to wiped area and kinematic behavior requirements since the early phases of vehicle development, this paper makes use of a MATLAB optimization function to optimize the windshield wiper system. The main goal is to achieve the maximum wiped area by optimizing wiper blades lengths and orientations. Parallel to that, constrains make the method finds the optimum kinematic design for the windshield wiper linkage in terms of mobility, available area to fix the linkage on body and the maximum range of the blades oscillatory motion. This optimization is applied on an existent windshield wiper system of a domestic passenger car to present the benefits of the developed model.

The fact that single-track vehicles do not necessarily roll without slipping must be taken into account in the analysis of certain motions of such vehicles. This paper deals with kinematical questions arising under these circumstances. Constraint equations are formulated for motions involving side slip unaccompanied by longitudinal slip, expressions for side slip velocities are developed, and comparisons are drawn between the kinematical consequences of assuming rolling without slip and rolling with side slip.

The Kinematical models and Emulation of muti-axle steering of off-highway vehicles had been researched in this paper,that included the kinematical model of dozens of steering linkages, the relationship model of the steering linkages, the minimum steering radius and the wheel alignment, the mathematical model of the steering linkages and the steering system, and the model of the stability of the vehicle. The theory and method of the linkages optimization of multi-axle vehicles had been researched with kinematics theory. The simulation had been done on the multi-axle steering linkages of a eight-axle(8 X 8) off-highway vehiele, and the optimal parameters of the linkages had been obtained accordin to the simulation result and the optimal theory.

In this paper, a Magneto-Rheological (MR) fluid semi-active suspension system was tested on a commercial vehicle, a domestic light bus, to determine the performance improvements compared to passive suspensions. MR fluid is a material that responds to an applied magnetic field with a significant change in its rheological behavior. When the magnetic field is applied, the properties of such a fluid can change from a free-flowing, low viscosity fluid to a near solid, and this change in properties takes place in a few milliseconds and is fully reversible. A quarter suspension test rig was built out to test the nonlinear performance of MR damper. Based on a large number of experimental data, a phenomenological model of MR damper based on the Bouc-Wen hysteresis model was adopted to predict both the force-displacement behavior and the complex nonlinear force-velocity response.

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.