Marine buoy feasibility

Hello,

I'd like to make a small buoy (probably made of polystyrene) to be put in the water. It would have GPS capability with a pre-set longitude and latitude. Should it drift away from it's coordinates, little propellers would slowly bring it back into it's original position.

-So-

  1. Is this possible with Arduino?
  2. If so, what components would be needed?

I imagine the following would required: GPS module, a couple of motors, an antenna, a battery and some sort of arduino board?

Apologies, I've never worked with Arduino but it sounds like a lot of fun

Cheers

You omitted the critical components - about ten square metres of solar panels.

Or a NASA grade isotope thermopile.

Forget the Arduino.

First work out how much battery power would be needed to cope with the expected current wind and current drift.

Do some tests with the parts you would find in a normal radio controlled model boat.

Paul__B:
You omitted the critical components - about ten square metres of solar panels.

Or a NASA grade isotope thermopile.

A small BUOY (maybe 150mm diameter), not a small BOAT

eBoy:
A small BUOY (maybe 150mm diameter), not a small BOAT

There would not be as much difference as you think. You will need a lot of energy to fight against wind and currents. Think of dynamically positioned ships.

Actually a boat shaped hull (provided it could be steered) would have less drag than a circular buoy.

The buoy (or boat) will have to be big enough to contain the batteries needed to store power for night-time position keeping.

Have you considered using wave energy to recharge your batteries?

I think this is the type of project which does not scale down to the small size you are thinking of.

...R

Robin2:
There would not be as much difference as you think. You will need a lot of energy to fight against wind and currents. Think of dynamically positioned ships.

Actually a boat shaped hull (provided it could be steered) would have less drag than a circular buoy.

The buoy (or boat) will have to be big enough to contain the batteries needed to store power for night-time position keeping.

Have you considered using wave energy to recharge your batteries?

I think this is the type of project which does not scale down to the small size you are thinking of.

...R

Boy I tell ya - you can never seem to get a straight answer on forums. You've all automatically assumed I want to leave it in the water for years at a time. You have no idea what I want to use it for or for how long.

Fellas, I'm prepared to build something, have it miserably fail, and then learn from my mistakes. These worried responses never get us anywhere. For the love of god, can someone who is far more intelligent than me be a straight shooter - if you're advice ends up being a complete disaster, I will not be angry.

X

eBoy:
Boy I tell ya - you can never seem to get a straight answer on forums. You've all automatically assumed I want to leave it in the water for years at a time. You have no idea what I want to use it for or for how long.

I can't think how we made that mistake after all the extensive information that you provided :slight_smile:

...R

PS ... Even after criticising us for jumping to conclusions I note that you still have not provided the data that might have avoided our mistaken assumptions.

OK, let me give you the straight answer.

eBoy:

  1. Is this possible with Arduino?

Yes.

  1. If so, what components would be needed?

I imagine the following would required: GPS module, a couple of motors, an antenna, a battery and some sort of arduino board?

Sounds pretty much like it. Don't forget the floating waterproof container aka buoy itself.

If you want more detailed answers, you have to provide more details.

wvmarle:
OK, let me give you the straight answer.

Yes.

Sounds pretty much like it. Don't forget the floating waterproof container aka buoy itself.

If you want more detailed answers, you have to provide more details.

You sir, are a God. I thank you. Fair call on the lack of details too - in the future I'll be more specific.

All the best

I wonder if Robin2 has been receiving sanctimonious PMs from eBoy, or was I the most obvious target?

The OPs project would sink or swim on the ability of the buoy to have enough power to combat the drift, and that has zilch to do with Arduino. Even a Mega 2560 would not improve the situation.

As is typical on here, we were provided with redacted information on the project, so can only provide guesses as to whether the project is feasible or not.

Paul__B:
I wonder if Robin2 has been receiving sanctimonious PMs from eBoy, or was I the most obvious target?

Nah Robin2 is fine, he made some fair calls - I'll try and be better because of him

#takeiteasy

a little late to the party, but ...

if you use the GPS, you could put it in the yard and have it just use green light red light to prove that part works.

Seems the warning of how much power needed have been offered.

if you do the yard or field thing.....
you could put markers were it went from green to red in a circle to show about where it would see that it moved.

if you want to stay in the center of a 10 meter circle,
once you leave, you could move back to the center, or, move all the way till you went to far, then just drift back.
the latter would run the power less often.

funny that you said it is not a small boat. a portable generator could be the power source for the generator for the motor.

as for your learning, this seems like a great opportunity to learn !

ps : thumbs up on asking about a project that is original, we cannot say, look at the forum for the last week we did that one already.

dave-in-nj:
a little late to the party, but ...

if you use the GPS, you could put it in the yard and have it just use green light red light to prove that part works.

Seems the warning of how much power needed have been offered.

if you do the yard or field thing.....
you could put markers were it went from green to red in a circle to show about where it would see that it moved.

if you want to stay in the center of a 10 meter circle,
once you leave, you could move back to the center, or, move all the way till you went to far, then just drift back.
the latter would run the power less often.

funny that you said it is not a small boat. a portable generator could be the power source for the generator for the motor.

as for your learning, this seems like a great opportunity to learn !

ps : thumbs up on asking about a project that is original, we cannot say, look at the forum for the last week we did that one already.

Thanks man, you're not late all. Really do appreciate it!

eBoy:
2) If so, what components would be needed?
I imagine the following would required: GPS module, a couple of motors, an antenna, a battery and some sort of arduino board?

You'll most likely need a compass as well. If the GPS tells you where you are, and you know where you want to be, you next have to know which way you're facing to then start turning around and pushing in the right direction.

There are plenty of DIY ROV thruster examples floating around the net and one of these designs would likely be good. Motor current on a thruster able to push a milk jug at 4 Km/hr would be above 3A and you'll also need a couple of motor controllers -- maybe just some MOSFETs if you want to cheap out. Brushless DC motors make good thrusters and a suitable ESC for them would be a good bet too.

My phone and my car GPS both indicate direction i am looking

No Idea how

dave-in-nj:
My phone and my car GPS both indicate direction i am looking

They might be able to work out the direction you are moving (your course over the ground) using changes in your position. They certainly cannot tell where your eyes are pointing :slight_smile:

...R

If they could we would probably all be arrested

Those devices may also have a compass built in. My current phone doesn't seem to have one; a few phones ago I definitely had a magnetic compass sensor in it. It would know if I simply turn my phone around.

Of course change in GPS position is also a clue as to where you're pointing.

Robin2:
They might be able to work out the direction you are moving (your course over the ground) using changes in your position. They certainly cannot tell where your eyes are pointing :slight_smile:

...R

If they could we would probably all be arrested

My eyes would be looking at My phone.

As i spin my device around a stationary point the map i am looking at reorients to the direction I am facing.

wvmarle:
Of course change in GPS position is also a clue as to where you're pointing.

This is very unlikely. Your movement is driven by a combination of wind and current, which are likely in different directions. If you are under power this will contribute to the overall movement vector, but orientation is unlikely to be discernible just from movement.