All models are lumped-parameter, nonlinear and large amplitude. They include detailed kinematic & compliance data, aerodynamics and tire models. With only small differences, the same input files (containing measurements & descriptions of the vehicle and tires) are used with all four simulations.

Customers often request specific features which MRA then adds to the computer model. These features may remain proprietary to that customer for a period of time.

We emphasize that these programs are not animations. They are complex engineering calculations based on measured vehicle/tire data and understanding gained from a long history of research into the science and physics of automobile vehicle dynamics.

The MRA Nondimensional Tire Model is available in each of the comprehensive vehicle simulations. This powerful and mathematically consistent approach to tire data has shown significant advantages over other tire modeling schemes. Furthermore, MRA has a number of smaller vehicle simulations and vehicle dynamics utility programs (e.g., a Tire Data Plotter for graphing tire data from simulation input files). These can be made available on specific request.

MRA's comprehensive vehicle dynamics programs are:

MRA Moment Method, MMM: A non-linear, quasi-steady-state analysis that predicts vehicle handling over the full lateral and longitudinal acceleration range, including limit behavior. MMM has many parallels to the static analysis of stability and control widely used in aircraft design. Windows or DOS-box interface. Over 100 engineering vehicle parameters are output. Postprocessor to generate moment method diagrams, response plots and friction circle diagrams.

Lap Time Simulation, LTS: Uses a trimmed version of the MMM static analysis to predict performance on a race track. Determines overall lap time and over 100 engineering vehicle parameter outputs at up to 2000 locations around the track. Windows or DOS-box interface. Multiple output formats. Includes track map utility.

Vehicle Dynamics Simulation, VDS: Time-based simulation used for complete (and partial) non-linear dynamic simulations of steering, ride and handling characteristics. Ideal for detailed study of transient maneuvers or particular problem areas (e.g., transient load transfer, on-center steering). Over 220 engineering vehicle parameters are output.

Vehicle Dynamics for use with MATLAB/Simulink, VDMS: Similar to VDS, this time-based vehicle simulation is programmed in Simulink and run through MATLAB. Much of the program code is open to the user for additions (e.g. to develop control systems). Over 200 engineering vehicle parameters are output variables. MATLAB GUI plotter. VDMS has been included by The MathWorks, Inc. in its MATLAB Connections Program.