Plot Tire Model Response for Visual Inspection

Step 5 of 7 in Get Started with the Extended Tire Features for Vehicle Dynamics Blockset

Use the tireModel class and the plot method to visually inspect tire model responses without tire data. First, create a tire model object. A tire model object can be created from imported parameters, default tire model type parameters, or built-in model parameters. This example uses the built-in "Mid-size passenger car 235/45R18" model. Then, specify arguments in the plot method to customize different plot views.

This example requires the Extended Tire Features for Vehicle Dynamics Blockset™ support package. See Install Support Package.

Note that all built-in models are Magic Formula 6.2 tire type models.

Create Tire Model from Built-In Model

Create the tireModel object tm from the built-in model, "Mid-size passenger car 235/45R18".

tm = tireModel.builtin("Mid-size passenger car 235/45R18");

Display the result using disp.

Autoplot Tire Data

To create a generic tiled plot with common sweep data, plot tire model tm with no additional input arguments. Slip conditions, except for the sweep direction, are set to zero. The normal force Fz conditions are equally spaced between the defined minimum FZMIN and maximum FZMAX wheel load of the model. All other operating conditions are set to the nominal or estimated conditions of the model.

plot(tm);

Plot Tire Model Response

The optional input arguments Direction and Magnitude define the slip direction to plot. Provide additional input arguments, such as the normal force Fz, inflation pressure IP, and inclination angle gamma, to further define model operating conditions.

Define Sweep Direction

Specify the input argument Direction as alpha to plot the lateral force versus the slip angle, using the slip angle as the sweep direction.

Note that when the magnitude is not explicitly defined, the magnitude is set to the minimum and maximum values for that slip direction in the model. The varying steady-state condition sets Fz equally spaced according to the FZMIN and FZMAX values for the model. The y-axis is set to an appropriate data channel for the defined slip direction.

plot(tm,"Direction","alpha");

Define Magnitude

Specify the input arguments Direction and Magnitude to plot the lateral force versus slip angle, with the slip angle defined as the sweep direction with a range of -0.35 to 0.35.

Note that Magnitude must be a scalar or vector of length two. If a scalar is provided, the sweep magnitude is +/- of that value.

plot(tm,"Direction","alpha","Magnitude",0.35);

Define Operating Conditions

To plot the lateral force versus slip angle, specify the input arguments Direction and Magnitude. Specify the input arguments Fz, IP, and gamma to define operating conditions. If a data channel is an array, each value in the array is set, and the plot uses the data channel as the ColorBy value to assign colors and legend values to the plot. If the data channel is set as the direction and the data channel is also defined, the data channel value is ignored.

plot(tm,"Direction","alpha","Magnitude",0.35, ...
    "Fz",[2000,3000,4000,5000,6000],"IP",220000,"gamma",0);

Define Data Channels to Plot

Specifying the input argument DataVariableNames, plot the self-aligning moment versus the slip angle in the direction of the slip angle. Additionally, specify the operating conditions for Magnitude, Fz, IP, and gamma.

plot(tm,"DataVariableNames",["alpha","Mz"], ...
    "Direction","alpha","Magnitude",0.35, ...
    "Fz",[2000,3000,4000,5000,6000],"IP",220000,"gamma",0);