Refine Your Search




Search Results

Technical Paper

135 Days in Isolation and Confinement: The Hubes Simulation

The EUROMIR-95 flight was selected as model for the HUBES experiment: a similar duration (135 days), a similar crew (3 men), similar schedule organisation (8 hours work, 8 hours sleep, 8 hours off-duties), similar workload for the crew and the mission control (performance of scientific experiments), similar setup for communication and data processing, and similar layout of the MIR station, as the simulation was performed in the MIR simulator located at the Institute for BioMedical Problems (IBMP) in Moscow. The Scientific Programme of HUBES had been elaborated by integration of 31 experiments from more than 80 research proposals from Principal Investigators from Europe, USA and Russia, in domains of Physiology, Psychology, Operations and Technology.

2-D CAD Template for SAE J826 H-point Machine

This document describes the 2-D computer-aided design (CAD) template for the HPM-1 H-point machine or HPD available from SAE. The elements of the HPD include the curve shapes, datum points and lines, and calibration references. The intended purpose for this information is to provide a master CAD reference for design and benchmarking. The content and format of the data files that are available are also described.
Technical Paper

2-Door Vehicle Body Local Force Evaluation with the IIHS, EuroNCAP, and LINCAP Side Impact Barriers

Structure enhancement based on data monitored in a traditional side impact evaluation is primarily a trial and error exercise resulting in a large number of computer runs. This is because how the structure gets loaded and the degree of contribution of local structural components to resist the impact while absorbing energy during a side collision is not completely known. Developing real time complete load profiles on a body side during the time span of an impact is not an easy task and these loads cannot be calculated from that calculated at the barrier mounting plate. This paper highlights the load distribution, calculated by a procedure using computer aided engineering (CAE) tools, on a typical 2-door vehicle body side when struck by moving deformable barriers used in the insurance institute for highway safety (IIHS), EuroNCAP and LINCAP side impact evaluations.
Technical Paper

3-D Crash Analysis Using ADAMS

The dynamics of vehicle front end crash are studied using the ADAMS dynamic simulation code. The analysis is carried out in three dimensions and can capture the behavior associated with an asymmetrical structure or impact mode. Subroutines which allow the modeling of structural crush and plastic hinge formation, contact forces and friction forces are discussed. The method is relatively inexpensive, but does require a good understanding of the problem on the part of the analyst. A discussion of the techniques that are used to model the structural system is given. The results of the analysis are compared with experimental data and the correlation is very encouraging.
Technical Paper

3-Dimensional Simulation of Vehicle Response to Tire Blow-outs

Sudden tire deflation, or blow-out, is sometimes cited as the cause of a crash. Safety researchers have previously attempted to study the loss of vehicle control resulting from a blow-out with some success using computer simulation. However, the simplified models used in these studies did little to expose the true transient nature of the handling problem created by a blown tire. New developments in vehicle simulation technology have made possible the detailed analysis of transient vehicle behavior during and after a blow-out. This paper presents the results of an experimental blow-out study with a comparison to computer simulations. In the experiments, a vehicle was driven under steady state conditions and a blow-out was induced at the right rear tire. Various driver steering and braking inputs were attempted, and the vehicle response was recorded. These events were then simulated using EDVSM. A comparison between experimental and simulated results is presented.
Technical Paper

3D Deformation and Dynamics of the Human Cadaver Abdomen under Seatbelt Loading

According to accident analysis, submarining is responsible for most of the frontal car crash AIS 3+ abdominal injuries sustained by restrained occupants. Submarining is characterized by an initial position of the lap belt on the iliac spine. During the crash, the pelvis slips under the lap belt which loads the abdomen. The order of magnitude of the abdominal deflection rate was reported by Uriot to be approximately 4 m/s. In addition, the use of active restraint devices such as pretensioners in recent cars lead to the need for the investigation of Out-Of-Position injuries. OOP is defined by an initial position of the lap belt on the abdomen instead of the pelvis resulting in a direct loading of the abdomen during pretensioning and the crash. In that case, the penetration speed of the belt into the abdomen was reported by Trosseille to be approximately 8 to 12 m/s. The aim of this study was to characterize the response of the human abdomen in submarining and OOP.
Technical Paper

3D-Design, Fabrication and Metrological Characteristics for Knee Meniscus Replacement Prototype using Proposed Polymeric Material

Due to the accidents of the motor vehicles and the osteoporosis, many people enface a lot of troubles and sometimes necessities for replacement of their knee joints. Practically, mechanical properties and surface characteristics of Total Knee Replacement (TKR) are very important parameters for improving the performance response in human. The meniscus is a small element and an essential part of the TKR. The knee meniscus has special feature allows the easy dynamic loading and motion of leg and foot with high accuracy and good balance. Therefore design and analysis of the geometrical shape for the meniscus replacement is worthy to be studied. In this paper, a proposed design using a computer software package has been presented. 3D simulation analyses of a variety of meniscus thickness and different materials under different loads are investigated. The compression stresses and surfaces deformations are determined numerically through the Finite Element Analysis (FEA) technique.
Technical Paper

4994 Tractor Hydraulic System

J I Case Company has produced four-wheel-drive agricultural tractors since 1964. In 1984 however, the flagship of the Case fleet changed hands. Rising labor costs and larger farming operations spearheaded the need for a more efficient larger tractor. January 1984 marked the introduction of the largest four-wheel-drive tractor in the history of Case, the 4994, a 400-gross engine horsepower tractor, Figure 1. Sheer horsepower alone however, would not meet the requirements of today's farming operations. Case Engineering realized that tomorrows tractors must have sufficient power to handle the wide variety of attachments available. They also realized that along with the unmatched power must come precise control of the attachment. These advancements in farming have required improvements to the tractor hydraulic system. This paper describes the hydraulic system of the 4994, Case's new flagship.
Technical Paper

5-years status report of the advanced offset frontal crash protection

This paper will provide an overview of the work progress of the advanced offset frontal crash protection group of IHRA. It resumes, including tables, the strategy of the group to cope with the assigned task. This is the commitment to achieve an harmonized frontal crash protection procedure taking into account the different world wide views in this field.
Technical Paper

61 Fundamental Analysis of Motorcyclist Injury Risk Using A Statistical Model Based on Real-world Crashes

This paper describes the risk of injury to the rider in a crash using a statistical model based on real-world accident data. We analyzed the road traffic accidents data in Los Angeles and Hanover. Logistic regression modeling technique was used to clarify the relationship among probabilities of minor, serious, fatal injury risk to the rider, and the influence of risk factors in accidents involving opposing vehicle contact point, motorcycle contact point, opposing vehicle speed, motorcycle speed, relative heading angle of impact, and helmet use. The odds ratio, which was adjusted for risk factors simultaneously, was estimated by using the developed technique, and was compared with the effects of risk factors individually. The results showed that there was a statistically significant relationship between minor and serious injuries and opposing vehicle speed, motorcycle speed and opposing vehicle contact point.
Technical Paper

62TE 6-Speed Transaxle for Chrysler Group

A new six-speed transaxle has been introduced by the Chrysler Group of DaimlerChrysler AG. Along with the six forward ratios in the normal upshift sequence, this transaxle features a seventh forward ratio used primarily in a specific downshift sequence. A significant technical challenge in this design was the control of so-called double-swap shifts, the exchange of two shift elements for two other shift elements. In the case at hand, one of the elements is a freewheel. A unique solution is discussed for successful control of double-swap shifts. The new design replaces a four-speed transaxle but makes use of a large percentage of parts and processes from the four-speed design. This approach enabled the new transaxle to reach production in three years from concept. The new transaxle, referred to as the 62TE, has substantially improved performance and passing maneuvers coupled with a new 4.0L high output engine for which the 62TE was developed.
Technical Paper

64 Ergonomic Approaches to Improved Scooter Riding Comfort

This paper gives a report on ergonomic approaches we tried to scooters for improvements in their riding comfort. First we conducted investigations into riding postures that offer a comfortable scooter ride. That is, we picked out major items for the evaluation of scooter riding postures and investigated a correlation between those items and their physical quantities. Our investigation revealed that room for leg and arm movements played a major role in a scooter riding posture. We further found out a high correlation between the evaluation items for legroom and the knee angles and also high correlation between the evaluation items for legroom and the ankle angle. Next we report on the result of the attempt we made at improved riding comfort by equipping the scooter seat with a backrest. To check the effects of backrest, we measured the seating pressure distribution, myogenic potential, and cardiogenic potential.
Technical Paper

A 0-D Calculation Template to Define Crush Space Requirement and Body Front End Force Level Requirement in Concept Stage

Today’s automotive world has moved towards an age where safety of a vehicle is given the topmost priority. Many stringent crash norms and testing methodology has been defined in order to evaluate the safety of a vehicle prior to its launch in a particular market. If the vehicle fails to meet any of these criteria then it is debarred from that particular market. With such stringent norms and regulations in place it becomes quite important on the engineer’s part to define the structural requirements and protect the space to meet the same. If the concept level platform definition is done properly it becomes very easy to achieve the crash targets with less cost and weight impact.
Technical Paper

A 100 G Frontal Crash Sled Test System

This paper describes the development of a new sled system that can address many safety-related issues pertaining to the racing industry. The system was designed to re-create acceleration and velocity levels similar to levels evident in race car crashes. The sled utilizes equipment typically used in passenger car crash research with the primary change to a specially designed lightweight carriage. This paper will overview the system and the types of crash events that can be simulated. Readers of this paper will gain a much broader understanding of accelerator sled testing and the issues related to the simulation of high speed crashes using physical testing.
Technical Paper

A 25 Degrees of Freedom Hand Geometrical Model for Better Hand Attitude Simulation

Numerical models are used more and more to visualize a human operator within a work environment and simulate his movements. Many models are limited in their ability to simulate complex activities like prehension and objects manipulation. The hand models proposed in the literature are relatively simple, especially assuming the palm as a rigid body, which leads to unrealistic representations of complex attitudes. The objective of the present study is to develop a more advanced hand model, able to properly simulate prehension postures. A 25 degrees of freedom (DOF) hand model has been proposed including 2 DOF for representing the palm arch. Compared to the model without palm arch, the proposed model has made significant improvement of the hand posture representation, suggesting the need of including palm arch for simulating complex hand grasping attitudes.
Technical Paper

A 2D Vehicle-to-Vehicle Crash Model for Fleet Analysis (Part-I)

This paper presents a 2D model for frontal vehicle-to-vehicle crashes that can be used for fleet modeling. It presents the derivational details and a preliminary assessment of the model. The model is based on rigid-body collision principles, enhanced adequately to represent energy dissipation and lateral engagement that plays a significant role in oblique frontal vehicle-to-vehicle crashes. The model employs the restitution and the apparent friction in order to represent dissipation and engagement respectively. It employs the impulse ellipse to identify the physical character of the crash, based on the principal directions of impulse. The enhancement of the rigid body collision model with restitution and apparent friction is based on collision simulations that use very simple finite element vehicle representations. The dependence of the restitution and the apparent friction on the incidence angle, the frontal offset, and the mass ratio, as predicted by the 2D model, has been presented.
Technical Paper

A 30 mph Front/Rear Crash with Human Test Persons

A great deal of data is available concerning accident simulation tests with test dummies or cadavers but in comparison there is very little material on tests involving living volunteers. This paper describes crash tests and sled tests with human test persons and Hybrid II dummies. To obtain a realistic accident simulation the tests were run with standard Audi 80 vehicles fitted with the standard seat belt systems. The results clearly demonstrate that none of the test persons sustain any kind of physical injury at a precisely defined level of accident severity (vehicle-to-vehicle crash at a collision speed of approx. 30 mph). In some cases considerable differences are revealed between the loadings imposed on the dummies and the human test persons.
Technical Paper

A 3D Finite Element Model of Pelvis in Side Impact

A 50th percentile male pelvis finite element model was designed for impact simulation. Shell elements represented the pelvic bone, which geometry was taken into account. Non linear viscous springs accounted for soft tissues connecting skin to bone structure, and body segments inertia around the pelvis were represented using rigid bodies. Geometric and mechanical characteristics were taken either from litterature or by identification to in house experimental results. Three dimensional movements were reproduced by the model for static lateral loading and dynamic lateral impact simulation at two different velocities, 3.5 and 6.5 m/s, with a good agreement with experimental results. This model takes into account pelvic bone geometry, allowing an appreciation of its deformation and therefore injury risk.
Technical Paper

A Basic Study on Modeling of Forearm Torsional Operations for Digital Human

The purpose of this study is to propose a method to evaluate operations involving forearm torsion, such as screw driving and knob turning, for digital human models. The rotational ranges of an object gripped with a hand and the working postures of the upper limb were measured at various positions of the object. The results demonstrated that the rotational ranges of the object varied depending on the working posture. The degree of coincidence was defined among direction vectors for each segment in the link model consisting of the upper limb and the rotated object. A method was proposed to estimate the rotational ranges of the object from the degree of coincidence. Based on this method, software has been developed in order to evaluate operations involving forearm torsion.
Journal Article

A Bayesian Approach to Cross-Validation in Pedestrian Accident Reconstruction

In statistical modeling, cross-validation refers to the practice of fitting a model with part of the available data, and then using predictions of the unused data to test and improve the fitted model. In accident reconstruction, cross-validation is possible when two different measurements can be used to estimate the same accident feature, such as when measured skidmark length and pedestrian throw distance each provide an estimate of impact speed. In this case a Bayesian cross-validation can be carried out by (1) using one measurement and Bayes theorem to compute a posterior distribution for the impact speed, (2) using this posterior distribution to compute a predictive distribution for the second measurement, and then (3) comparing the actual second measurement to this predictive distribution. An actual measurement falling in an extreme tail of the predictive distribution suggests a weakness in the assumptions governing the reconstruction.