Input to MMM is through two ASCII files, a vehicle file and a tire file. These input files are, with small differences, also compatible with VDS and LTS. They also contain the same data as the VDMS input files (but VDMS uses a different format).

The vehicle file is a fixed-format ASCII file. Click here to view a page from a sample vehicle file. The MMM User's Manual contains a detailed description of the inputs and input file format. For a sample of the User's Manual, click here.

The vehicle file contains information on program control as well as the vehicle description. The user may input up to 50 vehicle sideslip angles and 50 steer angles for a simulation run.

MMM represents the vehicle as a lumped-parameter system with 14 degrees of freedom: 6 chassis, four vertical unsprung, four rotational. The model contains a choice of solid or independent front or rear axle, each of which is modeled separately. The chassis longitudinal, lateral and yaw degrees of freedom are constrained by D'Alembert inertial forces and the wheel rotation degrees of freedom are constrained to quasi steady-state responses subject to acting torques.

Suspension kinematics and compliances are input in polynomial or tabular form. Several choices are available for modeling normal force coupling. Six-component aerodynamics with yaw sensitivity, several differentials and and a brake system model are included. Left/right asymmetric vehicle parameters (as for an oval track race car) may be input, or a symmetric vehicle may be specified.

The tire file is an ASCII file containing inputs for various tire models. Tabular tire data as well as sophisticated tire models such as MRA's Nondimensional Tire Model are available. Click here to access the separate description of the Nondimensional Tire Model (Note: Following this link will leave the MMM Tour).

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