In crash dummy models two different mathematical formulations can be distinguished:​ multibody techniques and finite element techniques. Both approaches offer their specific advantages and disadvantages. Multibody techniques are particularly attractive for the simulation of crash dummy segment motions and complex joint behaviour. Finite element techniques allow the calculation of local deformations in dummy segments.

The use of combined multibody and finite element techniques, the so-called hybrid approach, allows the user to benefit from the capabilities of both approaches and offers the flexibility of merging more global models with, whenever needed, detailed representations of certain parts in the model.

In this paper the strategy for hybrid modelling is illustrated. Several examples of recently developed and validated hybrid models will be presented in order to demonstrate the potential of this technique. In the examples flexible bodies and arbitrary shaped contact surfaces are shown to be efficient and accurate alternatives to traditional modelling methods. Criteria which can guide the user in the selection of the optimal setup of a crash dummy model are formulated and future developments are indicated.