Looking for matlab implemantion of an underwater vehicle model

Hello

I am looking for a matlab implementation of an autonomous underwater vehicle (AUV) model, along with a controller/autopilot. It is not important what AUV-type it is in particular, only that the vehicle can move in any direction, i.e. it should not only be able to move in the direction of its currect orientation (as is the case with Fossen's AUV in his GNC toolbox). The model doesn't have to be very accurate at all, only to some extent capture the dynamics of an underwater vehicle.

The controller should be able to steer towards a waypoint, while also being able to control the orientation.

If anyone know of such an implementation freely avaiable I would be very grateful.