Knowledge Base

Article Number: 3 | VC6 | VC5 | VC4 | VC3 | Post Date: June 30, 2016 | Last Updated: June 30, 2016


How do I change the moments-of-inertia for my vehicle? 

This process is described in Chapter 6 of the User's Guide. First, go to the "mass properties" menu in the left side control panel.

You will see "type:car" is automatically specified. This feature automatically sets the moments-of-inertia based on overall mass, wheelbase, and geometrical size for vehicles [1,2]; that is:

where m is the vehicle mass in kg, WB is the wheelbase in meters, and L is the overall length in meters.

Note, for type:truck, only the mass and geometrical size are used (note, type:truck is generally used for heavy (commercial) type vehicles. SUVs and pick up trucks are typically assigned type:car by default). So for type:truck, we have by default (based on the prism method) [1]:

where m is the vehicle mass in kg, W is the overall width, and L is the overall length. 

To use your own values, simply press the "type" button and select "user." 

You should now see accessible fields in which to enter your own values for Ixx, Iyy, and Izz.



Additional reading:

[1] "A Comparison of Moment of Inertia Estimation Techniques for Vehicle Dynamics Simulation," MacInnis, Cliff, and Ising, SAE 970951

[2] Handbuch der Verkehrsunfallrekonstruktion, 1. Auflage, Burg, Heinz.


Tags: Changing moment of inertia, moments, mass properties. 


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