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Interaction between External and Internal Behavioral Models

During a simulation, when external behavioral models are loaded and enabled, the update vehicle process is determined by the following algorithm:

for each Vehicle:
    apply external lane changing method if implemented 
    otherwise apply the default internal lane-changing model
endfor
for each Vehicle:
    apply external car following method if implemented 
    otherwise apply the default internal car following model
endfor
for each Vehicle:
    Aimsun Next then updates all vehicles according to the new lane, speed, and positions.
endfor

When an external model is active, this algorithm forces an update of all vehicles using the external behavioral models and, in case that the external model does not update the vehicle, Aimsun Next applies its default behavioral models. It assures that every simulation step all vehicles are updated. This implies that a subset of vehicles and/or by time and/or by location can be updated using the microSDK.