OpenMarine

Full Version: OpenPlotter in Model Boat?
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Folks,

I've set myself a challenge of building a solar powered autonomous model boat which will (hopefully!) go around the world.

I'm just at the information gathering stage at the moment so I've broken the project up into a number of areas like hull, comms, propulsion, solar charged batteries and navigation.

The question I have is, could I use OpenPlotter as a headless autopilot for the boat?  Essentially what I'm looking for is a system which would follow a series of waypoints and automatically keep itself way from land if it moves off course.  It would also need to automatically recover from a power outage if the batteries run out of charge and drifts off course.  It would have to make relevant navigation changes if it wakes up with land between itself and the next waypoint - staying away from land is the priority over heading to the next waypoint.  I was planning to run it on a Raspberry Pi with a Grove hat to allow me to attach a number of sensors (GPS, compass, gyro, temperature, etc) which would all feed into the system.   

Could I use OpenPlotter to achieve this?  I see that OpenPlotter uses PyPilot and OpenCPN but I'm not sure I understand their relationship.  Would this combination all me to create this autonomous boat?

Please let me know if this is feasible so I don't waste too much time going in the wrong direction.

Also, I've never had any type of boat before (model or otherwise) so any other relevant suggestions of advice you have would be very gratefully received. 

Thanks muchly!

Dòchas 
You are going to need special logic to achieve this. pypilot is mostly intended to replace existing autopilots, so this is the function implemented. pypilot is intended for full sized boats.

The project ardupilot is intended for autonomous vehicles, however it does not have the same steering dynamics of pypilot (I don't think it will steer as well) but if you are using servo motors for steering it may not matter for your particular case. There are not really many comparisons done.

In many situations it can impossible to avoid getting blown ashore if the wind is strong especially with limited solar power.

Did you consider:
1) making it submersible (can completely avoid getting blown on land or lose ground wrong strong winds)
2) giving it sail power. This way it can avoid getting blow on land too, but more importantly, the wind is much more powerful and with a lot more energy available than you can harness from solar.
Hi,

Thanks for your reply.

I wasn't sure if I could use PyPilot to ensure that the boat would stay on track and away from land. If this is possible, then I shall continue to look at the software. If there is any way I can use this pre-built software and maps of the coast line then that will save me a lot of hassle trying to code my own.

I have had a look at AdruPilot, but it seems that you need a basestation which monitors the device. It also seems that it will only do waypoint navigation, and it will not take avoiding land into account.

Yes, I understand that the boat will be at the mercy of the wind and current for a lot of the time. I'm hoping that it will be alive for enough time to stay away from land as much as possible.

I did consider your points but since I will need to keep it topped up with solar power and will have to check in with location data, I can't make it fully submersible. I was hoping to give it as low a profile as possible to keep the wind contact as low as possible. I was also considering a micro wind generator to harness some of the wind power in addition to the solar power to assist with recharging.

I quite quickly dismissed sail power - I realise that this would be the most efficient propulsion system and would allow the boat to move with very little electrical output, but I honestly don't think I have enough money and expertise to implement an automated sailboat.

Thanks again for your thoughts.

Dòchas
(2021-04-05, 05:01 PM)Dòchas Wrote: [ -> ]Hi,

Thanks for your reply.

I wasn't sure if I could use PyPilot to ensure that the boat would stay on track and away from land.  If this is possible, then I shall continue to look at the software.  If there is any way I can use this pre-built software and maps of the coast line then that will save me a lot of hassle trying to code my own.  

I have had a look at AdruPilot, but it seems that you need a basestation which monitors the device.  It also seems that it will only do waypoint navigation, and it will not take avoiding land into account.

pypilot doesn't specifically avoid land either, so either way you have to write your own land avoidance code. As for the maps of the coastline, extracting the important details from vector charts is non-trivial.
Quote:Yes, I understand that the boat will be at the mercy of the wind and current for a lot of the time.  I'm hoping that it will be alive for enough time to stay away from land as much as possible.

Maybe you should use a solar-powered hydrogen zepplin instead? This way it does not need to avoid land.

Quote:I did consider your points but since I will need to keep it topped up with solar power and will have to check in with location data, I can't make it fully submersible.  I was hoping to give it as low a profile as possible to keep the wind contact as low as possible.  I was also considering a micro wind generator to harness some of the wind power in addition to the solar power to assist with recharging.  
It is really difficult to make efficient wind generators as they decrease in size. Using a wind generator to power a vessel directly works but generally is a fraction of the power of an actual sailing rig.
Quote:I quite quickly dismissed sail power - I realise that this would be the most efficient propulsion system and would allow the boat to move with very little electrical output, but I honestly don't think I have enough money and expertise to implement an automated sailboat.

Thanks again for your thoughts.

Dòchas

Ok, well if you are solar only, I think it could take a very very long time for a small boat to circumnavigate, think in terms of 3 or more years.
(2021-04-05, 07:49 PM)seandepagnier Wrote: [ -> ]
(2021-04-05, 05:01 PM)Dòchas Wrote: [ -> ]Hi,

Thanks for your reply.

I wasn't sure if I could use PyPilot to ensure that the boat would stay on track and away from land.  If this is possible, then I shall continue to look at the software.  If there is any way I can use this pre-built software and maps of the coast line then that will save me a lot of hassle trying to code my own.  

I have had a look at AdruPilot, but it seems that you need a basestation which monitors the device.  It also seems that it will only do waypoint navigation, and it will not take avoiding land into account.

pypilot doesn't specifically avoid land either, so either way you have to write your own land avoidance code.   As for the maps of the coastline, extracting the important details from vector charts is non-trivial.

Yes, I can understand it's going to be a tough job, which is why I was hoping that this software might already do that.  I was hoping that people in a full size boat would want their autopilot to keep away from land as well as hit waypoints.

Quote:Yes, I understand that the boat will be at the mercy of the wind and current for a lot of the time.  I'm hoping that it will be alive for enough time to stay away from land as much as possible.

Maybe you should use a solar-powered hydrogen zepplin instead?   This way it does not need to avoid land.

Big Grin  It is starting to sound like a easier option, but I think that would hit a lot more red tape!

Quote:I did consider your points but since I will need to keep it topped up with solar power and will have to check in with location data, I can't make it fully submersible.  I was hoping to give it as low a profile as possible to keep the wind contact as low as possible.  I was also considering a micro wind generator to harness some of the wind power in addition to the solar power to assist with recharging.  
It is really difficult to make efficient wind generators as they decrease in size.   Using a wind generator to power a vessel directly works but generally is a fraction of the power of an actual sailing rig.

That is really interesting.  This is all new to me so I'm still gathering info.
Quote:I quite quickly dismissed sail power - I realise that this would be the most efficient propulsion system and would allow the boat to move with very little electrical output, but I honestly don't think I have enough money and expertise to implement an automated sailboat.

Thanks again for your thoughts.

Dòchas

Ok, well if you are solar only, I think it could take a very very long time for a small boat to circumnavigate, think in terms of 3 or more years.

Sure, I'm not expecting it to come back in a hurry.  I'm just doing this for a hobby and to track it's progress and see where it goes.

I really appreciate your thoughts and feedback.  I hope I can eventually get something in the water!

Dòchas