Correctly fitted seat belts save the lives of car passengers everyday. In attempt to reduce the risk of injuries, primarily abdominal, caused by inappropriate belt fitting, Transport Canada developed the Belt fit Test Device (BTD). The BTD is a physical hardware measuring device that tests whether the lap and torso belt are appropriately positioned with respect to the bony structures of the pelvis and rib cage of the restrained occupant.
To overcome the deviations of hardware physical tests and to enable review of belt design in early design phases, the Alliance of Automobile Manufacturers funded the development of an electronic simulation and modeling tool in the form of an electronic Belt fit Test Device (eBTD). The development takes place in close co-operation with the Joint Working Group on Abdominal Injury Reduction (JWG-AIR).
The introduced 3D belt routing simulation model takes into account the belt width, the kinematics of belt anchorages, belt types, contact of belt with seat, and the location and position of the belt fit test device itself. Different techniques were used to evaluate the model in which physical tests were compared with simulation results.
The algorithm has the potential to be used to model different human sizes and statures. This could allow for the assessment of different occupant populations and non-standard driving postures. Furthermore, it demonstrates the potential for the study of realistic belt routing parameters through simulation. This could be used as a basis for addressing future safety belt related issues, such as belt comfort, accessibility, etc.