Design a cascade PI controller for the DC motor speed controller developed in laboratory $3.$ The cascade controller has the objective to split the control problem in two portions: $1)$ a closed loop control of the motor speed and $2)$ a closed loop controller of the motor current. The close loop dynamics of the current controller should have a response time of $10$ms whereas the closed loop dynamic of the speed controller should have a time response of $0\mathrm{.}1$ second. Use the pole$-$zero tuning technique for each PI controller.