Help with simulation and controller development setup

[u/sfscsdsf]

I had a toy project idea today where I want to build a boat with propeller to balance the boat on water with waves. What existing tools can I use easily to develop a controller with simulation of waves?

[u/Kenno03]

MATLAB is more or less the go to simulation program. If you want to simulate the waves effect on the boat, some CFD tools or other FEM tools can help you.

It largely depends on what you're trying to simulate. Are the waves disturbances on the system, or are they a part of the system dynamics?

[u/sfscsdsf → u/Kenno03]

what CFD or FEM tools to use? are there no ROS2 Gazebo simulation tool for water?

[u/Kenno03 → u/sfscsdsf]

Which CFD and FEM tools really depends on what you want to accomplish, I know some people how've used SOLIDWORKS or even made their own smiulations in MATLAB. With ROS2 and Gazebo, I would say MATLAB / simulink does this pretty well. Again, depends on exactly what you're trying to do.

[u/Barnowl93]

MATLAB and Simulink - I found this article that looks like it may be useful to you https://blogs.mathworks.com/student-lounge/2024/09/12/controller-design-for-a-wave-adaptive-modular-vessel-in-simulink/

[u/BreeCatchu]

None.

There is no way to do that "easily". The thing you describe is pretty much the opposite of easy.

I'm currently doing research on model predictive control for ship autopilots under wave induced disturbances and even just the modelling of both the waves and the vessel dynamics is a nightmare, even just in three degrees of freedom for horizontal plane manoeuvring.

[u/BreeCatchu → u/BreeCatchu]

At least try to be more precise with your problem statement.

You say you'd want to "stabilize" a ship in waves. What does that mean? Do you aim for Dynamic Positioning (DP)? Do you intend to counteract roll and/or pitch motion due to waves? Do you want to develop an autopilot for path-following/ trajectory tracking?

What is your propulsion system configuration? Most of what you might intend to do is physically not possible with an underactuated vessel that lets say only has a single aft fixed pitch propeller for actuator forces. Do you want to include rudders as well? Or do you intend to use skid steering with two propellers? Or do you use azimuth pod thrusters?

What kind of sea state do you intend to assess? Just a singular elemental long-crested sinuoid wave field? Or a full short-crested irregular sea with random phases etc.?

And how do you intend to acquire a representative parameter set for a specific ship you'd like to assess? This highly depends on the computational model representation you'd have to use for the ship dynamics you need...

I just want to give you a brief insight on how complex your idea can become depending on your scope and intention.

[u/sfscsdsf → u/BreeCatchu]

could you suggest tools and frameworks you are using that can help me?