If you were to make the command
dothedrive the default command for the cassie subsystem, you wouldn't have to specifically call it in the Robot class as long as you have an object of the subsystem there. You can do this by adding this line inside your initDefaultCommand() inside your cassie subsystem
Code:
setDefaultCommand(new dothedrive());
It is best to add a default command inside your subsystem than calling all the commands from the Robot class