This report describes the work performed by TNO Automotive in tasks 2.3, 2.4 and 2.6 of the ECBOS project, a European Union funded research project that aims to improve the passive safety of bus passengers. Frontal impact simulation models of a bus and a bus interior were created and evaluated using test results. Using those simulation models, the most significant seat parameters were optimised. The target of the optimisation was to reduce the inury values recorded in the dummies. An optimal set of characteristics for the most significant seat parameters was defined. Data from a real crash involving three busses and a truck was used to create a full-scale frontal crash model of an M3 bus. The crash pulse of the M3 bus was extracted from the full - scale model and used as input for the simulations with the interior model. A simulation model representing the sled set - up [2] was created and the Hybrid 111 5", 50`h, and 95`h percentile dummy models were positioned in the model. The ECE R80 pulse was applied to the model, and the kinematics were compared with kinematics from the inverse sled tests. The structural parameters of the seat models were then varied and an optimisation was performed. A set of seat characteristics resulting in injury values within the legal requirements was defined for each dummy and each configuration: unbelted, two point belt, and three point belt. Additional simulations were performed to study alternative scenario's: the 5`h percentile unbelted model and the 95`h percentile three-point belt model, and having a bulkhead installed in front of the bus passenger. The validity of one set of seat characterisitcs was evaluated in different test configurations. The seat model from the optimisation with the 50`h percentile dummy was combined with the deceleration pulse from the full-scale reconstruction. This configuration was used in simulations with the 6 year-old, 5`h, 50`h, and 95`h percentile Hybrid III dummies. The injury values resulting from these simulations were evaluated. In the same interior, the interaction of multiple occupants was simulated using the ECE R80 pulse. (Author/publisher)
Samenvatting