**4.2 System modeling**

To make the project simple and manageable, only a two-dimensional movement in which the system moves in one plane will be considered. The two motors are assumed to move together symmetrically when an identical input is given. Although this is unlikely the case, it is a good approximation for motors which are manufactured as the same product. A control voltage is applied to the motors, which results in displacement of the wheels and change in angular attitude of the body. A mathematical model for the system is obtained by observing the free body diagram.
