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This paper illustrates how Digital Human Modeling (DHM) tool functionality can be increased through the development of industry specific features. The features are based on a design tool, the Mobility Gallery, established by the cooperating health care company. Each resident in the Mobility Gallery has different levels of functional mobility and is described with different personal characteristics as well as background details. The integration of the resident descriptions in a commercial DHM tool is presented and discussed. The rationale for this approach is that the synthesis of DHM tool functionality and the Mobility Gallery descriptions will render a DHM tool with features offering augmented applicability for product design in a health care setting.

The objective of this study was to examine to what extent ergonomics simulations of manual assembly tasks correctly predict the real outcomes in automotive assembly plants, and if recommended measures originating from ergonomics simulations are considered. 155 ergonomics simulation cases done by nine simulation engineers at Volvo Car Corporation in Gothenburg were used in the study. The evaluations of the ergonomics conditions in reality of the cases were done by six professional ergonomists working in the company. The results show that digital human modelling tools are useful for providing designs for standing and unconstrained working postures as well as for the design of various auxiliary devices and their needed space for movements. The study also identifies areas that require additional development in order to improve the digital human modelling tools’ ability to correctly predict a work task's real outcome.

This paper presents the results of an effort to compare figure posturing results within and between simulation engineers. The simulation engineers simulated four manual tasks. Alternately they used a posture prediction tool, and alternately they were only allowed to apply manual adjustments of the body angles. The simulation engineers repeated each task six times and always with at least six days between each occasion, to minimize the subject's rememberance of how she/he carried out the cases. Results show that the use of a posture prediction tool, in such complex tasks as the study includes, neither reduces needed time to fulfill a simulation, nor differences within or between simulation engineers. Differences in simulation results often originate from the different assumptions the simulation engineers have of the task when positioning the manikins.

The organization of upper body and gaze movements was quantified as an attempt to identify the types of task descriptors associated with the visual and manual functions of movement control. Nine subjects were asked to either read a word (high visual demand), reach a target (low visual demand), or simultaneously read a word and reach the object target placed just below the word (high visual demand). Similarly the manual demand condition was either low or high, depending on the target distance from the shoulder (either 80 or 120% of extended arm length, respectively). Torso flexion and gaze-on-target duration showed that movements are influenced by the both visual and manual demands in an interactive manner. Also both torso posture and gaze movements were predominantly changed by the visual demand. These results suggest that tasks to be simulated should be described in terms of both visual and manual demand.

The aim of this study was to identify and measure time-consuming human modelling tool activities. Five human modelling tool users at Volvo were observed for five days each. The results showed a wide distribution of both indirect and direct working tasks, as well as non-value added tasks such as waiting time. Most of the activities identified appear to be necessary to perform human modelling simulations of high quality. However, the time distribution could be questioned to some extent. There are many activities associated with communication, including a variety of contacts and meetings, where there appears to be potential to increase efficiency.

The objective of this paper is to investigate whether different appearance modes of the digital human models (DHM or manikins) affect the observers when judging a working posture. A case where the manikin is manually assembling a battery in the boot with help of a lifting device is used in the experiment. 16 different pictures were created and presented for the subjects. All pictures have the same background, but include a unique posture and manikin appearance combination. Four postures and four manikin appearances were used. The subjects were asked to rank the pictures after ergonomic assessment based on posture of the manikin. Subjects taking part in the study were either manufacturing engineering managers, simulation engineers or ergonomists. Results show that the different appearance modes affect the ergonomic judgment. A more realistic looking manikin is rated higher than the very same posture visualized with a less natural appearance.

Developers, reviewers and users of human simulation tools claim that the use of these tools may reduce development time and development cost. However, before these benefits will be fully visible, there are some barriers to overcome. The aims of this case study are to identify which departments at Saab Automobile use some sort of human simulation tool today, and to identify the information flow and procedure when the tool is used. Four departments crash safety, packaging, production planning and vehicle ergonomics were identified as direct users of human simulation tools. The tools used were finite element with crash dummy representation, SAE human model, Safework and Ramsis. Communications between human simulation tool users are limited. Communications are done through the project management. The crash safety and packaging departments have formal descriptions of the human simulation process, whereas production planning and vehicle ergonomics have no formal process descriptions.

Industries strive to minimize their development costs, to shorten the time required for development and to increase the quality of the product. The paper summarizes three ergonomic evaluation methods developed for the automotive industry. The first method presents a manikin with a movement pattern similar to people. The second method is a tool to evaluate comfort that can be combined with a manikin. The third and last, is a methodology for eliciting user comments. Ergonomic evaluation methods and tests with a computer support and generate information that may lead to reduced product development cost. These kinds of tools are also suitably used in cross-functional project groups in order to visualize alternative designs, and evaluations in a participative process. Visualization of traffic, driver and eye-movements seems to open up the discussion and is a step to a more user-centered design process.

In the ANNIE project - Applications of Neural Networks to Integrated Ergonomics - BE96-3433, a tool for integrating ergonomics into the design process is developed. This paper presents some features in the current ANNIE as applied to the design of car interiors. A variant of the ERGOMan mannequin with vision is controlled by a hybrid system for neuro-fuzzy simulation. It is trained by using an Elite system for registration of movements. An example of a trajectory generated by the system is shown. A fuzzy model is used for comfort evaluation. An experiment was performed to test its feasibility and it showed very promising results.