Fiala Tire

The FIALA tire model serves as the first stepping stone in full vehicle simulation because it is simple enough to be comprehended completely by the MBD analyst. Furthermore, the forces and torques produced by the tire/road interaction use a series of physically meaningful parameters.

It is easy to obtain such parameter values for a wide variety of real tire models via straightforward measurements, and therein lays the value of this simple tire model.
On the other hand, the FIALA tire model makes a series of assumptions when computing forces and torques. These restrict its applicability only to a limited set of vehicle maneuvers that do not violate the following simplifications:
  • Rectangular shape of the contact patch.
  • Uniform distribution of contact patch forces.
  • Gyroscopic torques due to the inertia of the tire carcass are neglected. However, these may be accounted for by adding the mass and inertia of the tire to the wheel.

This model has been updated to include the effects of camber forces and moments. It is important to keep in mind that no real tire behaves as described above, therefore the applicability of the FIALA tire model is limited primarily to vehicle handling on smooth road surfaces.

To use the FIALA tire model select a tire property file whose [MODEL] block specifies:

  • Property_file_format = ‘USER’
  • Function_name = 'mbdtire::USER_FIALA'