Plot Tire Model Response with Imported Tire Data for Visual Inspection

Step 6 of 7 in Get Started with the Extended Tire Features for Vehicle Dynamics Blockset

Use the tireModel and tireData classes and supporting methods to import tire data to plot the response of a tire model or calculate and plot a tire response.

First, create a tireModel object using the tireModel.builtin method. This example uses the built-in "Mid-size passenger car 235/45R18" model. Next, import the tire data from Tyre Data Exchange Format (TYDEX) v1.3 files. Then, specify arguments in the plot method to compare the tire model response versus the imported tire data. Finally, use the compute method calculate a tire response and plot the original tire data versus the calculated response to inspect the difference.

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.

Import Tire Data

Build a string array of the TYDEX filenames.

tirepath = pwd;
tydexdir = dir(fullfile(tirepath,"data_tydex_files","*.tdx"));
tydexstr = join([{tydexdir.folder}',{tydexdir.name}'],filesep);

Import the data and create an array of tireData objects, td.

td = tireData(tydexstr);

Use the mean function to preprocess the Fz data channel to remove noise and variation.

td = mean(td, "Fz");

Autoplot Tire Data

Specifying the input argument Data, plot the array of tire data objects overlaid with the tire model. Generic plots automatically generate providing a fast way to observe how a model behaves compared to the tire data for a variety of sweep directions and data channels.

plot(tm,"Data",td);

Plot Imported Data Overlayed with Simulated Model Response

Specifying the input arguments Data, DataVariableNames, and ColorBy, plot the longitudinal force versus longitudinal slip of the tire model overlaid with the tire data. Use the normal force to assign legend colors and values.

plot(tm,"Data",td(1:8),"DataVariableNames",["kappa","Fx"],"ColorBy","Fz");

Simulate Tire Model Response

Specify the input argument Model to simulate the model response at the plotted data conditions.

plot(td,"Model",tm);

Compare Tire Data and Tire Model Response Defining Additional Operating Conditions

Specifying the input arguments DataVariableNames, ColorBy, FilterBy, FilterByValues, and Model plot the longitudinal force versus lateral force of the tire data overlaid with the tire model response. Use the slip angle to assign colors and legend values to the plot. Filter by the combined data and inclination angle values of -0.2 and 0.2.

plot(td,"DataVariableNames",["Fy","Fx"],"ColorBy","alpha", ...
    "FilterBy",["TestMethod","gamma"], ...
    "FilterByValues",{"Combined",[-0.02 0.02]},"Model",tm);

Calculate Tire Response Using Tire Model Parameters

Use the compute method to calculate the tire response from the tire model tm using the data in td. A tireData object, td_response, is returned with the simulated data.

Note that if a data channel is empty when executing the model solver, the data channel will be estimated or assigned to the model nominal condition.

td_response = compute(tm,td(1));

Plot Tire Data

Use the plot method to visually inspect the difference between the original data and simulated data.

td(1).Comments = "Original Data";
td_response.Comments = "Simulated Data";
plot([td(1),td_response],"DataVariableName",["kappa","Fx"], ...
    "ColorBy","Comments","MarkerSize",15)