Problem $5,10$ pt

A schematic diagram is sketched in Fig. $2\mathrm{.}51.$ The motor has an electrical constant Ke $,$ a

torque constant $Kt,$ an armature inductance $La,$ and a resistance $Ra.$ The rotor has an

inertia J$1$ and a viscous friction B$.$ The load has an inertia J$2.$ The two inertias are connected

by a shaft with a spring constant $k$ and an equivalent viscous damping $b.$ Write the

equations of motion. And obtain the transfer function from Va to angle theta$\_2$

The same example is shown in the class. Please try to redo the derivation by yourself.