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In modern society the automobile is an essential companion in everyday life. Be it commuting to and from work or during our leisure time - every week most of us spend many hours sitting in their car. In this context the seat is the main interface between the human being and the automobile itself. Functioning well, this close relationship can foster the well-being of the passenger and raise his spirit; being flawed it can otherwise cause severe pain in the back after a longer journey. Thus, for car manufacturers, the aspects of seat comfort are becoming more and more prominent in distinguishing themselves from their competitors. Despite its importance the development of comfort parameters in automotive seating is still being consigned to the subjective judgements of a poor number of seating experts or randomly selected test subjects.

The perception of visual information is the major input requirement for the psychological cognition process. The quality of perception of visual information is impaired by the geometrical and optical conditions of the displayed information. This concerns all technical information of the car as instruments, optical indicators, telltales and control displays. The international widely-used 3D-Man-Model System RAMSIS receives some additional functionality for analysis and practical design to simulate these viewing conditions in the car. These new RAMSIS functions include methods for the analysis of sight shadows, limits of visibility of liquid crystal displays, the time of focus shifts of the driver and the modelling of the optical parameters of head-up displays. These capabilities will enable a RAMSIS user to allow for (degraded) visual performance when designing the rising number of user interface displays in cars and airplanes.

This paper presents the usage of the Digital Human Models (DHM) PCMAN and RAMSIS to determine parameters for a supported ingress and egress on a mock-up. Sports cars with lower seating positions show occurring difficulties among older drivers during ingress/egress. To equip sports cars with higher seats or narrow door sills seems limited due to design aspects. Therefore the idea of an ingress/egress support system arose. To build a mock-up, it needs specific dimensions already in the CAD design phase. Here DHM-systems are utilized. As no similar systems are known, no ballpark figures for trajectories of the seat or movement ranges can be derived from literature. Therefore pre-tests were done with a simple manually moved seat. Test persons showed high acceptance and discomfort reduction. In order to design a proper testing environment for repeatable and reliable results, a variable seat with electric motors is built into a mock-up with a package of a sports car.

Cutting development times in car manufacturing means bringing forward the knowledge processes. Simulations based directly on CAD data reduce or replace time-consuming hardware loops significantly and therefore make a significant contribution to this. Ergonomic product design is an area that is challenged as far as the further development of virtual methods is concerned. Simulation of the static and quasi-static positions of passengers inside the car is the current state of the art in ergonomic product design. For this reason, interest is strongly focused on the simulation of complex movement processes within the context of enhancing simulation tools. For the car manufacturer, the manner in which people enter and leave the car is of particular interest. Getting into the car is the customers' first actual contact with it. It may also develop into a serious problem for car drivers, as they get older.

During early phases of interior car layout a lot of different aspects have to be considered like crashworthiness, regulations, philosophy of the company etc.. Ergonomic aspects do not always play the most important role in these cases. Since aspects of comfort in cars are getting more and more important in nowadays these aspects should be taken into account very early in the interior car layout process. This paper shows a way to design the interior layout of a car from scratch for a good postural comfort for all anthropometries with the aid of a digital human model (RAMSIS). The novelty of this approach is to use the digital human model to design the interior and not to verify or correct an existing one.

This paper concerns a former experimental study of the Lehrstuhl für Ergonomie of TU München, where in the first step correlations between pressure and discomfort were found for the seat pan. In the second step these findings were validated for long term discomfort. Now an additional correlation for the back should be found, which is essential for later research. In this context tests conducted before should now be confirmed and validated by another seat comfort model with a higher number of subjects and a long term test, too. Interesting part of this study will be the intercorrelation between seat pan and back.

The Lehrstuhl für Ergonomie of the Technische Universität München is working on a generalized strength based discomfort model of posture and movements. By evaluating individual discomfort feelings of subjects regarding different postures, movements and different levels of force the first steps to find this function are realized. Different measuring machines permit the measuring of torques / force moments inside all joints of the human body. The individual feeling of discomfort is evaluated by using the CP50-scale for every fixed joint angle as well as every measured value. Discomfort is depending as well on the posture as on the level of force applied in a certain posture. Additionally the direction in which a certain force has to be applied influences discomfort feelings. Regarding different levels of force applied in a fixed posture the discomfort feeling increases linear with growing percentages of the maximal force/torque.

This paper introduces a concept of predictive active safety by means of a full redundant architecture with the driver, from the perception of the environment to the vehicle controllers. The bottleneck of the current driver-vehicle association will be analyzed first. Then a virtual driver and the safety envelope of the different maneuvers will be described. A decision control will be presented that it matches the driver's command in this safety envelope. It is designed to give adequate feedback to the driver and can safely perform the command to the optimum of the chosen maneuver.

Today digital 3D human models are widely used to support the development of future products and in planning and designing production systems. However, these virtual models are generally not sufficiently intuitive and configuring accurate and real body postures is very time consuming. Furthermore, additionally using a human model to virtually examine manual assembly operations of a vehicle is currently synonymous with increased user inputs. In most cases, the user is required to have in-depth expertise in the deployed simulation system. In view of the problems described, in terms of human-computer interaction, it is essential to research and identify the requirements for simulation with digital human models. To this end, experienced staff members gathered the requirements which were then evaluated and weighted by the potential user community. Weaknesses of the simulation software will also be detected, permitting optimisation recommendations to be identified.

When investigating the posture comfort in vehicles two important influencing factors can be distinguished: In order to evaluate these influences a combined laboratory-field-experiment was carried out. A real car was equipped with cameras to record the body posture and the joint angles. The static forces exerted by the driver on his contact points were recorded in a corresponding mock-up. The forces to maintain the body posture were calculated. The following results were found:

The ergonomic design of automobiles has changed over in the last years. It is increasingly being transferred from the usage of two-dimensional templates of the human shape to computer-aided manmodels. So far these models were mainly used for static anthropometric investigations on the drivers workplace. Dynamic questions can be answered only very insufficiently. In the context of this work a methodology was developed to precalculate target directed human movements in a motor vehicle environment with the CAD-manmodel RAMSIS. A new two-piece model was developed. In this model dynamic boundary conditions, so called dynamic restrictions, for any movement in a car are determined, concerning outside parameters. In the following, the entire bodyposture is determined by a statistical posture probability model, considering these dynamic restrictions. A control theory of human movements was derived from the field of neurophysiology.

Some systems like the ESP already exist to support the driver for the stabilization of the vehicle. But the next generation of active safety system will have to deal with a wider environment of the vehicle, to go closer to the limit of the vehicle dynamic etc. With such a complexity the systems will also have to take into account their own limits and to reduce their actions when they have a low confidence, e.g. when sensors are degraded. This article describes firstly a virtual driver and secondly a decision control that fuses their command depending on their confidences in order to improve the reliability of the command level.