In recent years comfort has become more important for car manufactures to distinguish themselves from their competitors. The seat comfort or discomfort is very important because the seat is the main interface between user and car. However, seat discomfort can only be evaluated very late in the product development process by physical prototypes. It would be a big advantage for the developer to be able to check the seat discomfort by virtual seat tests. One component of virtual testing is to utilize a digital human model to simulate the contact forces between human and seat. The other part is to have a tool to interpret the results gained from simulation, especially the contact force distribution. The presented study is split into two parts: the first part was the finding of a relationship between discomfort and pressure distribution in the seat pan. The second part was the validation of this model for long term discomfort and with this for use in daily life. A relationship between pressure and discomfort could be obtained. As important measures the following parameters could be found: percentage of load on body part, gradient, maximum pressure and mean pressure. Not a single parameter is crucial for the perceived discomfort. In fact all four parameters have to be considered. If all four parameters are according to the model the discomfort should be minimal. The hint from Hartung (2005) that the seats in experiments have to exceed the range of normal car seats can be strengthened since mathematical relationships could be found. The validation for long term discomfort showed that the overall discomfort was minimal for the 'ideal' setting. Since it was verified that this setting was according to the found model it can be concluded that the model for the seat pan is valid for long term discomfort. Furthermore the pressure distribution of the seat pan seems to affect the discomfort in the lower back. The existence of this relationship was investigated during conducting the experiments. With the successful validation of the model this study creates the possibility to check the long term discomfort of a seat by measuring the pressure distribution after a few minutes. Furthermore, the pressure distribution can be simulated in the computer by digital human models in a development stage far before physical prototypes. Based on a simulated pressure distribution combined with the knowledge showed in this study the seat can be optimized virtually to minimize discomfort.
Predicting long term comfort in cars
2007
22 Seiten, 10 Bilder, 5 Tabellen, 18 Quellen
Aufsatz (Konferenz)
Datenträger
Englisch
Predicting Long Term Riding Comfort in Cars by Contact Forces between Human and Seat
British Library Conference Proceedings | 2005
|Engineering Index Backfile | 1928
Engineering Index Backfile | 1928