Computer models of pedestrian humanoids and detailed vehicle models have been developed to simulate real world pedestrian accidents. The purpose of this modelling is to enable the design. development and evaluation of pedestrian safety technologies under more realistic conditions than the proposed European legislation in order to improve pedestrian safety. LS-DYNA3D has been used to provide an extensive range of modelling possibilities. This paper discusses the developments in the humanoid modelling concept, that was introduced in an earlier article. The validation of those parts of the humanoid that have been developed from original dummy parts are presented and the sensitivity of simulation results to variations in several important biological parameters are reported. Variations between adult and child simulations are presented and discussed.