Abstract
Caused by the requirements of the FMVSS 208 regulation in the United States, which require an advanced airbag system, a number of occupant detection and classification sensors are under development or in the market introduction. The most known systems are based on weight based sensors.
FMVSS 208 from May 2000:
The one fact that is common to all persons who dies is not their height, weight, gender or age. Instead it is the fact that they were very close to an airbag when it started to deploy".
This leads directly to the requirement of measuring the distance of the passenger head to the Airbag Module. In particular this is the case for rear facing child seats (RFCS), where the head of the child and parts of the child seat structure are very close to the Airbag Module. In order to protect these children, the FMVSS 208 allows weight based smart Airbag Systems, where the Airbag is switched OFF in presence of an Object with low weight. But for older children or adults weight systems can not give any output on the head position. To meet this requirement, it is not only necessary to measure the distance of the elements of the entire scene, it's also necessary to distinguish the head from an arm, leg, hand or other object by classification. Recent camera technology supports the spatial resolution, temperature range and a wide dynamic range for both - distance measurement and classification - under automotive conditions. This paper will describe two suited 3D Camera technologies for this application and the special case of the dynamic out of position sensing.