Common Workflow: positioning under gravity load

Use the BioRID-II model which has been prepositioned in a pre-processing tool of your choice. Position it as far as possible into an undeformed seat model without penetrating it. This should be the starting point of your seating simulation.

Run this simulation with gravity and little global damping for about 1 to 1.2 seconds. At the end of this simulation the dummy model should rest in equilibrium and the kinetic energy should be around zero.

Unless the dummy model does not reach the zero angle head position, you have to conduct a separate position correction by a simulation.

If the back set of the BioRID head is larger than desired, it is possible to rerun the positioning simulation again and push the BioRID at the T1 load cell backwards by using LOAD_NODE keyword. The load should only be used for a short time phase when the model has close contact to the seat. At the end of the simulation all external loads should be released.

Now – when dummy and seat model are in the desired position – assign the deformed geometry to your origin input decks.

In a further step read out the resultant forces of the discrete springs (ID 10500 and 10501) at the end of the seating simulation. Transfer the amount of the forces to the model input. We provided the two parameters (psfront and psrear) for setting these values.

Start your whiplash simulation run.