# Calculation of inertia values of Ic and Im

In my dynamic model of two wheeled mobile robot, it has the total equivalent inertia, noted $I$, described by the equation below, $I_c$ is the moment of inertia of the DDMR about the vertical axis through the center of mass and $I_m$ is the moment of inertia of each driving wheel with a motor about the wheel diameter. May I know how to measure or calculate $I_c$ and $I_m$? My wheeled mobile robot is Arduino Robot ## 1 Answer

You can find equations for the inertia of a cylinder on Wikipedia.

Using the equations for a solid cylinder will give similar results as if you calculated or measured the exact inertia of all the subcomponents.

The inertia of the wheels should include the inertia of the motor rotor and gears to be accurate. You can search for and find equations for this too.

You will need to disassemble the motor to get enough information.

Like mass, you can combine inertias by adding them together as long as they have the same reference axis (1D) or frame(3D).