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The possibility to check some requirements on the design is an important point to introduce the work of the ergonomists in early phases of the project. In this sense we developed a method for the simulation of the human motion during accessing to a vehicle and present an application in virtual prototyping of new car models. The method is based on the modulation of the kinematics of real movements acquired from subjects performing accessibility movements to a real car cockpit. This approach was applied with success to the different motor strategies shown by the subjects.

Within the development process of constructing and designing vehicles, comfort as an aspect of product quality occures to be more important. The recent developement of a new rating system, implements different aspects of scientific investigation in a multidisciplinary approach to build up an overall validation. The complex theoretical construct of comfort whith it's several aspects (i.e. postural comfort, seating comfort, thermal comfort) is split up into different criteria of evaluation. In a primary step investigation were made in order to define criteria for rating the aspects of posture comfort and seating comfort. For large persons possible deficits in design predominantly result out of the absolute size of the interior space. The limiting effects of qualitative seat characteristics predominantly surfaces in the sitting posture of small persons.

Current transportation safety interests involving the use of restraints in school buses, coupled with litigation claims arising from injuries to unrestrained occupants of school buses involved in rollovers, resulted in a study aimed at: understanding the biomechanical response and injury causing factors associated with unrestrained students involved in an actual school bus roll-over accident; and, comparing the unrestrained response condition to the hypothetical response if the students were lap belt restrained in the same rollover. A numerical occupant simulation computer code was used to input vehicle rollover motion to both belted and unbelted occupants. The unrestrained case theoretically duplicated the injury producing conditions that led to serious head and neck injury in certain students.

The Dutch are the tallest measured people in the world. One third of the Dutch male drivers population is not properly considered in SAE standards. The potential ‘matching-problem’ between Dutch drivers and present-day's driver workspaces is being investigated by the VIMS project team. A large amount of driver workspaces in passenger cars has been measured. The measurements have been converted to 3D CAD models to be able to evaluate them with RAMSIS. RAMSIS proved to be a helpful tool to investigate the influence of package design on the driving posture of Dutch drivers and to determine areas in the package design that may not be suitable for tall drivers.

For the interior design of a flight simulator, the ergonomic software MDHMS has been used to test different interior layout issues. The MDHMS program includes an accomodation analysis capability which generates a digital sample of the specific target group. This paper shows the data required for this analysis. Since there are just a few reference files available for only parts of the Dutch population, some methods to derive data from related files in order to make the chart complete are presented.

Three-dimensional (3D) whole body scanners provide an opportunity for collecting large quantities of precise point data on human forms. However, product designers will likely always need some access to traditional point-to-point dimensional measurements. These measurements can also be obtained from the 3D whole body scanner if appropriate software is developed. This project describes a validation test for a collection of software tools designed to extract traditional dimensions from 3D whole body scans. To validate the software we scanned 123 male and female subjects on a Cyberware WB4 whole body scanner. Subjects were also measured for point-to-point dimensions using traditional instruments. We compared the mean absolute differences between traditional and software measurements to interobserver error data collected in a large traditional anthropometric survey (ANSUR), and to various criteria specific to garment applications.

This paper will propose a specification that will allow any Human Figure Model (HFM) to be controlled by external sources such as Human Performance Process Models (HPPMs). The specification includes an enumerated set of actions - each with a set of parameters that describe how the action is performed. Return codes and queries are also supported to update the calling program on the status of the action. The specification will be proposed as a Society of Automotive Engineers (SAE) standard.

This paper describes a project to investigate methods and techniques to represent physical and perceptual activity in the context of cognitive models of human performance. The application of principal interest is that of constructing computer-generated forces (CGFs) for use in large-scale distributed simulations of military forces. Of the several frameworks currently in existence for simulating human behavior at both a cognitive and behavioral level, CHI Systems’ COGNET toolset represents a particularly attractive foundation for creating a tool to develop and execute CGFs. COGNET already possesses features that meet many of the human behavioral requirements of computer generated force models, including particularly its orientation toward representation of realtime, multi-tasking work environments.

The increased need for better human performance models results from a realization that comprehensive simulations cannot use human-in-the-loop for all players, as was originally thought. With system designers and decision makers demanding support from large-scale simulation models, the human performance component of computer models has repeatedly been found to be deficient. Each of the five communities involved with human performance modeling communicates with adjacent communities in a pair-wise manner, causing the customer to have little awareness of what is technically possible and the scientific community having little awareness of the needs of the customer.

ERGODATA was developed to provide basic data in the fields of anthropometry, biomechanics, and more generally ergonomics as well as statistical models of populations, with for instance a prediction of change in morphologies in the next 10-20 years to come. Individual Database (ID) and Aggregate Database (AD) in anthropometry contain worldwide surveys on various samples of subjects: males and females, civilians and military,… Specific databases were linked with ID and AD to collect and process experimental results on inertial properties, human strengths, as well as upper limb reach capabilities and movements for seated operators.. Bibliographic data and documentary sheets on norms and recommendations in ergonomics are also available. A new database focused on 3-D surface anthropometry will be added soon. All this information may be used to create and animate digital human models. ERGOMAN was developed for this purpose on EUCLID CAD software.

This paper documents several methods used to study shape change. The data from the “Accommodation and Occupational Safety for Pregnant Military Personnel” Study (commonly referred to as the “Pregnant Women's Study,” or “PWS”) is used to demonstrate these methods because it is easy to show the tracking of significant shape changes that occur over an extended period of time. The PWS data will help demonstrate the importance of visualization in the study of shape change and the advantages of three-dimensional (3-D) scanning for visualizing and understanding these changes. The methods for studying shape change discussed in this paper have a broad application and are not restricted to pregnant women. In fact, these methods for studying shape change are applicable to people who gain or lose weight, and to determining the shape change between people of varying body shapes and styles.

Efficient perception and evaluation of anthropometrical data forms the basis for human modeling methodologies. Since the early beginning of the development of the ergonomics tool RAMSIS in 1988 appropriate measurement systems had been developed simultaneously. Within our 3D-Body-Scanner development new integrated approaches and methods for human body measurement have been investigated and developed. The activities concentrated on both the development of a fast body scanner for three dimensional perception and the use of the 3D-CAD-manmodel RAMSIS as a necessary prerequisite for the interpretation of the range readings and automatic generation of an individualized 3D-Man-Model and body measurements. In this paper, an integrated process chain for individual production is introduced. In order to fulfill industrial requirements a complex measurement system has been developed, which combine high precision perception with high degree of automatism as well as minimal user interaction.

This paper presents a new approach for the classification and retrieval of three-dimensional images and models from databases. A set of retrieval algorithms is introduced. These algorithms are content-based, meaning that the input is not made out of keywords but of three-dimensional models. Tensors of inertia, distribution of normal vectors, distribution of cords and multiresolution analysis are used to describe each model. Scale, shape or color or any combination of these parameters can search the database. A user friendly interface makes the retrieval operation simple and intuitive and make it possible to edit reference models according to the specifications of the user. Experimental results using a database of more than 1000 VRML models are presented.

Validation of a new reaching algorithm for the Boeing developed CATIA Human Model was conducted prior to production release of the software. The validation covered both normal and maximum reach capabilities. Human subject and computer generated reach data were compared. For normal reaching, both the subjects and human models reached to the targets that were within reach, but the final body positions were not the same. For the maximum reach validation, problems with both the software and the data collection technique were discovered. Despite the discrepancies and problems found, the CATIA human model was found suitable for its intended use.

This paper presents the National Crash Survival Data Bank (NCSDB), a data base of impact acceleration test data available to researchers and modelers. We emphasize the contents and implementation of the NCSDB, a web-accessible object-relational data base housed at the National Biodynamics Laboratory (NBDL). Past and potential modeling applications of the data stored in the NCSDB are discussed.

With the increased number of airbags and other advanced restraint systems, the upper and lower extremities are becoming more widely studied to determine the injury potential from these devices. However, little injury tolerance data exist for whole bones. To address this deficiency, a finite element model of a female upper extremity was created from computed tomography scan data. A constant density of 1.86 g/cm3 was assumed with a previously developed transversely isotropic, elastic- plastic material model that incorporates rate effects through a modification to the longitudinal modulus and yield stress. Qualitative simulations were conducted for tension, compression, and torsion along the long axis of the bone and for three-point bending in the anterior-posterior direction. Failure was shown to occur in the area of weakest strength or greatest load.

This paper presents an automated approach in three-dimensional digital model generation of human joints based on MRI and CT scans. Since both the MRI and CT scans are going to be used in the digitization process, a systematic approach had to be taken in obtaining these scans. In this approach the CT and MRI scans are mapped in order to obtain the exact geometry of human joint. Due to the poor visibility of the hard or soft tissue contours because of the type of imaging used, additional smoothing techniques had to be developed. Attachment points of the ligaments are also identified. As it is well known in design and engineering area that the boundary locations and conditions are important in correct computations of the systems response. The approach described is then applied to a human tibia-femoral joint with soft tissue. The method described in this paper is applicable to live subjects but a cadaveric knee is used here in order to allow verification of results by other means.

The Federal Aviation Administration (FAA) has established the strategic goal for System Capacity and Air Traffic Services to improve accessibility, flexibility and predictability in the aviation community in order to reduce flight times, crew resources, maintenance, and fuel costs. Free flight is a system concept that addresses this goal. However, the potential for certain human performance costs arise, such as a increases in flight crew workload, or decreases in flight crew errors as predicted by Supervisory Control Theory. An evaluation of system costs associated with transitioning to Free Flight using two First Principles modeling approach, the Man-Machine Integration Design and Analysis System (MIDAS) and the Integrated Performance Modeling Environment (IPME) will be performed. IPME is expected to show differential human performance effects in cockpit and air traffic control system performance over those predicted by Air MIDAS over 50 Monte Carlo simulation runs.

The Boeing McDonnell Douglas Human Modelling System was evaluated in two experiments. One involving fit of manikins to actaul body scans and conventional data, and the other comparing manikin reach envelopes with human data. Systematic deviations in proportions were found, such as overestimation of sitting height and underestimation of sitting depth and hip width. Reach envelopes were roughly of the correct size, but somewhat displaced, which was traced back to erroneous shift of the shoulder joint. It is concluded that proportions, shoulder joint and lack of compression of soft tissue created undesirable deviations.

This paper describes the validation of RAMSIS, a 3-D CAD human model for ergonomic vehicle evaluation at General Motors (GM). The model’s capability to correctly predict position and posture in vehicle CAD environments was tested. H- and Eye point locations between RAMSIS manikins and their human counterparts were compared. We concluded that RAMSIS has good position and posture prediction capabilities and is a useful CAD ergonomic evaluation and design tool for vehicle interiors.