**2.1.3 Control**

The control system is responsible for providing the corrective signals to enable the vehicle to follow a desired path. This is achieved by receiving the desired state of the vehicle from the guidance system, and the current state of the vehicle from the navigation system. The control system then calculates and applies a correcting force, through use of the various actuators on the vehicle, to minimise the difference between desired and current states (Fossen, 1994, 2002). This allows the vehicle to track a desired trajectory even in the presence of unknown disturbances. Even though each of the aforementioned systems is responsible for their own task, they must also work collaboratively to fully achieve autonomy within an underwater vehicle setting.
