Active Child Models for Traffic Safety Research, Interim Report 1, October 2012

Rapport, 2012

The project Active Child Models for Traffic Safety Research is funded by Folksams Forskningsstiftelse. The overall aim is to increase the safety of child car occupants and thereby reduce the number of traffic induced injuries in 3 to 12 year-old children. This will be done by creating a computer model of a child that includes active musculature. The model will be used to reproduce emergency manoeuvres with biofidelic response at low acceleration levels. Literature on child safety has been reviewed with a main focus on child numerical models. Very few child models exist and for most of them, their response is validated against Anthropometric Test Devices (ATDs) certification corridors and not paediatric data. Models of children and child sized ATDs are either finite element or multi body models. Finite element models are more likely to predict injuries and contacts, whereas multi body models can preferably be used to reproduce kinematics in long duration events like emergency manoeuvres. Because of this, it has thus been decided to first work with child multi body models in the MADYMO code (TASS, Rijswijk, the Netherlands). The models that will be studied are the 6 and 10 year-old child facet models and the Q6 and Hybrid III 6 year-old ATDs available in MADYMO as well as the 6 year-old pedestrian model previously developed by Jikuang Yang at Chalmers University of Technology. Simulation activities have been planned and the models’ responses will be analysed and compared with kinematics data of child volunteers in emergency manoeuvres and sled tests. Then, based on their performance, one model will be chosen to implement active musculature. Extra experimental data for tuning and validation of the model may be required. As a consequence, new experiments on child volunteers are planned, including the acquisition of muscular activity. The model response will be compared to those results. Based on the active child multi body model capability to reproduce pre-crash events, it will be discussed and decided in January 2013 whether to continue with a multi body model or start the same process with a finite element model. In the long term, the active child model will be used to reproduce both pre-crash and in-crash events and help understanding the protective principles of forward facing children and how they interact with current and future vehicle safety systems and child restraints.