Sailing Robot

trubbert

I am actually in the process of exploring a SailBot (=Sailing Robot) project, based on a BS2.

The SailBot is a small (20 Inch) sailboat, that can navigate without external input along a preset route.

Input is highly welcome.

trubbert.

SciTech02

Verry interesting.· I'm just currious how it would turn, (I know the sail would turn, but if the wind is strong (or weak) would it not turn as well?).· However, the idea is neat.

A.C. fishing

I was thinking of something like this.
And found this: http://www.pooltoy.com/marsailboat.html
You really have to understand sailing for this to work.
Actually, it should be relatively simple.
I learned to sail over vacation. The simple, small sail-boats are the best.
like the one's used by those kids in Jaws II.
Two servos:
one for the rudder, and one for loosining the sail, and tighting it.
You should use pressure sensores on the sail, so the bot knows how hard the wind is blowing.
A mesmic accelerator so the bot knows when he is tipping
A home-made sensor the can tell wind direction.
And your object detection sensors.
Maybe a PING)) can be water-proofed and can tell the bot how deep it is up to a couple meters.
Would it be RC? I would use the Keychain and receiver,(found here[noparse]:http:[/noparse]//www.parallax.com/detail.asp?product_id=28005)
GPS guided?
Here is a good module: http://www.totalrobots.com/access_files/gps.htm
If you want to attempt this, LEARN TO SAIL!!!

trubbert

Thank you for your replies!

I·have already finished the boat. It is a radio controlled "Micro Magic". See http://www.micromagic.info/forum/index.php. I also have some experience in sailing as well as modell sailing. The problem with modell race sailing is the distance. It is simply hard to finetune the sail from the coast. That's how the idea was born...

The project should include a tilt sensor, a compass, a GPS receiver, 3-channels from the RC receiver (control, rudder, sail) and the two servos (sail and rudder)...

jeremya

Very Intresting idea. I new to Basic Stamps, but I am also a sailor (not r/c).
I would think GPS would be a must for navigation.
Wind direction would also be needed.
Something to measure the heel of the boat. It would be best to be able to know the amount of heel So you can change course or spill some air from the sails if the boat heeling too much.
Then your controls. I think that's all you'd need.

The tuff part will be writing a program to sail. You'll have to compensate for drift.

Good Luck!!
Jeremy

ellizard

Hi Trubbert

You said...
The SailBot is a small (20 Inch) sailboat,

and in another post: You said...
The project should include a tilt sensor, a compass, a GPS receiver, 3-channels from the RC receiver (control, rudder, sail) and the two servos (sail and rudder)...

• Have you considered the power needed for all this stuff?,OURs of duty full sinking! (of course of current) ?
• It wouldn't be an easy task to restrict the weights to bare minimum in order not to overload the sailing propertyes of the boat?
• I'm thinking especially to the Tx/Rx section of the Radio control, if you want information from the boat you'll have to have a Tx on the boat
  and Tx's are known to be hungry in energy.

I was thinking something similar but with primary function the safety factor for sailing alone on real sailboats, wat concerned me was the kind of servo
suited for the bigger force required, but this is out of thread...................

I'm not so informed about model sailing, but i love sailing, and i am curious to know few things about model sailing (if it's possible)..........

• Maximum speed of air that let you navigate with a sail model?
• With what fetch?
• Any Idea of the maximum speed reached?
  
  Thank you for the post
  Very interesting
  
  Stefano

Jonathan

Hi all,

>> The tuff part will be writing a program to sail. You'll have to compensate for drift.

Seems like you could get a rough idea of leeway from the degree of heel. The more the vessel is heeling, the more leeway. You could use this for DR. Then you could verify and compensate using the GPS.

What would nice would be a tilt compenstated compass. I am playing with a compass on a robot I am working on now, but it has no tilt compensation and is very sensitive to tilt. I'm not sure how well the GPS compass will work on such a small vessel moving slowly.

Neato project!

Jonathan

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www.madlabs.info - Home of the Hydrogen Fuel Cell Robot

jeremya

Yeah I wasn't really thinking he would use the GPS compass per se. He said he wanted it to travel a pre determined route. My thought was a GPS with waypoints would be a good way to do this, but you could be right in the fact that the GPS might not be accurate enough to give the correct position of the boat. In my 25 foot sailboat if I am 12-15 feet off it's not as big of a deal as it might be for a small boat in a small pond.

I suppose you could use heel to compensate for drift, but eventually the greater angle of heel will begin to spill air and drift will be less. Also angle the air is striking the sails could effect the amount of drift, but I am sure you could work out some averages.

Good Luck!

-- Jeremy

trubbert

elizard: Well, the small size is what makes it challanging. A Tx would be much too heavy and too hungry!
jeremya & jonathan: the tilt idea is a nice one, but it is far too complicated. it is far easier to set up a·course-/windspeed table for drift, based on prior experients. I am also aware of the tilt-problem with the compass I will face (I am using the HM55B). Relying on the GPS-compass is not a solution, as the GPS just gives one position per second...

Actually I am setting up the configuration for using the RC-Input to steer the boat, while·logging everything to EEPROM...

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colinsauze

I've built a similar robot (bit bigger). I originally used a B2sx but found it a bit limiting and am now using an ATMega128.
One thing i've found is that its a very good idea to build a hull which can sail in a straight line without any intervention from a computer so that the only time you really need to do anything is when you turn. So checking a GPS every few seconds would be sufficient to do this, but its worth having a compas too as when you stop moving the GPS can't tell you which way your going. We've managed to keep our compass level by building a swinging arm, there are also high-end (and expensive like $500+) compasses which automatically compensate.

There were recently two competitions held (one in France and another in Canada) have a look at:

http://web.ensica.fr/microtransat/

and

http://engsoc.queensu.ca/sailboat/competition/index.htm

for more information.

I've got some pictures and info about what i've done so far on my website at http://users.aber.ac.uk/cjs06/homepage/index.php?display=content/Research

A.C. fishing

There are remote control sailboats...
I bet a bot like this would need a tilt sensor, to make sure it won't tip... Servos could release the sail if the tilt sensor is saying the boat is tipping... and they would tighten the sail also. A standard servo could control the rudder, and maybe the boat could navigate using GPS. Maybe you could creativly use Vibra tabs to detect the direction of the wind...

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Somebody said...
-Never Underestimate the power of human stupidity.

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