2. Main scientific challenges and recent advances

2.1 Generation of models

For a user of a ND tool, the first question is how to define a group of dummies to represent the variability of the target population. Often, dummies are chosen to simulate extreme situations. For example, if the problem is to define the minimum height so that 90% of the target population can pass without risk of head-on collision, it's sufficient to take a dummy with a stature at the 90th percentile, below which 90% of the sample lies. But often the design problem involves the verification of multiple tasks, and several anthropometric dimensions may be critical for a single task. The choice of mannequins must be made according to the problem to be addressed. In general, an ergonomist, designer or engineer needs first to identify the critical body dimensions...