USING A VIRTUAL DUMMY TO SIMULATE VIBRATION DOSE VALUE FOR DIFFERENT CAR OCCUPANTS

The comfort assessment for car occupants is not an easy task to achieve. It is a matter of personal perceiving, thus a solution which may seem comfortable to one could be not to another. Moreover it is a field which requires knowledge both from science and medicine. The vibrational comfort analysis is the topic of this paper. There are different international standards to define the vibrational comfort through computed indices. In particular the British Standard BS 6841 (1) introduces the Vibration Dose Value (VDV). The main idea which lies behind the VDV is to estimate the whole body vibration. In fact the standard suggests the main locations for acceleration measurement (feet, seat and back) and their direction axes. The overall number of acquisitions is twelve. A numerical code for the vibrational comfort analysis of car occupants, estimating the VDV for each of them, has been developed. The code, named DAViD, is based on a multibody approach (2). It has been validated by means of experimental tests (3,4). In this paper the influence of the anthropometric features (height and weight) and the inclination of the backrest on the VDV has been investigated. The code is an useful tool for predicting at the seat design level the vibrational discomfort.

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