Allow to move the origin at a pre-described trajectory

[ufechner7]

For kites mounted on boats or other vehicles, the origin must be movable.

Model input pos_origin = f(t). Model output f_gnd = f(t).

[1-Bart-1]

You can already move a static point at discrete timesteps, but you want to be able to provide a function for the position?

Also, moving the origin itself is a bad idea, as this makes the world frame non-inertial, and we need an inertial reference frame.

[ufechner7]

Well, the wind reference frame is none inertial anyway, even though we treat it as such. If a ship is moving we need a way to inform the model about it. And just changing the position every timestep is probably not sufficient. You might also need the velocity as input.

In the end we need to define the coupling with the ship model. I suggest that the ship provides a new position, velocity and orientation at each timestep, and the kite power system model returns a force vector.

Then the moments are still missing, but we need to start simple.

[1-Bart-1]

If we add a coupled ship model it should be through a ship component, that can be connected to a point. Maybe we should look into MTK components, or we can add it as another struct.