I wonder if these things could be used at a mast head. No electronic auto pilot integration I guess. Pretty cheap though if they are any good.

www.ryda.com.au/la-crosse-c7970-professional-wifi-weather-station

Interesting thought, and perhaps the right person could hack the info to allow integration?

Select to expand quote

julesmoto said..
I wonder if these things could be used at a mast head. No electronic auto pilot integration I guess. Pretty cheap though if they are any good.

www.ryda.com.au/la-crosse-c7970-professional-wifi-weather-station

I purchased something similar with a similar idea but it relied on being mounted at a fixed compass point making it totally useless for my intended purpose as as the yacht constantly moves its alignment to compass north the wind direction is never correct. All else worked! It is now mounted on a pole and provides its intended external data/information feed for an internal head unit.
I cannot quite assess if this is similar but expect it is.

I have one of these plugged into a Raspberry Pi. Initial trials are good, perfectly suitable for what I want, a way for the autopilot to get apparent wind data, and also to help me know what the wind is doing at night (I lose a bit of awareness when I get sleepy). You do need to be clever with Raspberry Pis or other micro computers.

www.electricburst.com.au/products/davis-instruments-ds7911-anemometer?variant=40149270921293¤cy=AUD&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gad_source=1&gclid=Cj0KCQiA3uGqBhDdARIsAFeJ5r3nbOxgqn_qaVK9pLHvi3Nzni4zd7YSeI8CtBVTIv2qHCSbOEqpBswaAgB7EALw_wcB

This is another interesting option. www.madmanmarine.com/product-page/sailtimer-wind-instrument

Select to expand quote

Grith said..

julesmoto said..
I wonder if these things could be used at a mast head. No electronic auto pilot integration I guess. Pretty cheap though if they are any good.

www.ryda.com.au/la-crosse-c7970-professional-wifi-weather-station

I purchased something similar with a similar idea but it relied on being mounted at a fixed compass point making it totally useless for my intended purpose as as the yacht constantly moves its alignment to compass north the wind direction is never correct. All else worked! It is now mounted on a pole and provides its intended external data/information feed for an internal head unit.
I cannot quite assess if this is similar but expect it is.

Thanks, didn't think of that. No internal compass (if indeed that is the case as seems likely-although query what "dynamic compass rose" means in the specs) would obviously compromise any follow course auto pilot usage but should still be capable of steering angle to wind if the protocol could be translated to the chart plotter as Kankama has done.

The wireless and solar cell aspect would be good at this price if they indeed work up to 120m as claimed or even 120 ft! May be a little bulky tho. Would have to see in the flesh.

The below instrument came with my trailer sailer although I haven't been able to get it to work yet presumably either due to the battery in the head unit or the battery in the display or both. The Raymarine replacement batteries seem to cost a mint.

Those instruments are solar. If they have been in the box for awhile they may need charging. Leave them in the sun for a few hours if you haven't already tried. The batteries are about 80 euros each in France and plenty of vids on how to change them. Maybe a bit of internet searching and you will be able to find the same battery but not "Ray Marine" a lot cheaper.

Have to say, not a fan of cheap, however do like inexpensive, there is a difference.

If you are going down the route of hooking up an anemometer to a raspberry pie or similar it shouldn't be too much harder to add a magnetometer compass so you can calculate true wind. I wonder though, would you also need to include a boat speed sensor to allow you to account for any forward movement in your calculation?

Select to expand quote

UncleBob said..
Have to say, not a fan of cheap, however do like inexpensive, there is a difference.

or cost effective

Select to expand quote

Microbe said..
If you are going down the route of hooking up an anemometer to a raspberry pie or similar it shouldn't be too much harder to add a magnetometer compass so you can calculate true wind. I wonder though, would you also need to include a boat speed sensor to allow you to account for any forward movement in your calculation?

Yes you will need boat speed to complete the triangle of boat speed, apparent wind speed and true wind speed;

sailzing.com/understanding-apparent-wind/

This link included leeway angle also;

www.starpath.com/freeware/truewind.pdf

Select to expand quote

r13 said..

Microbe said..
If you are going down the route of hooking up an anemometer to a raspberry pie or similar it shouldn't be too much harder to add a magnetometer compass so you can calculate true wind. I wonder though, would you also need to include a boat speed sensor to allow you to account for any forward movement in your calculation?

Yes you will need boat speed to complete the triangle of boat speed, apparent wind speed and true wind speed;

sailzing.com/understanding-apparent-wind/

This link included leeway angle also;

www.starpath.com/freeware/truewind.pdf

Aha! Thanks R13 - that's some good info. And thanks Julesmoto for starting an interesting topic.

So all you'd need is a anemometer on the mast head to capture apparent wind speed and direction, an electronic compass to supply boat heading, a GPS to provide SOG and COG and a paddlewheel to get speed through the water. From that you can calculate true wind, leeway and current. Although I'm not sure how to work out how much the difference between SOG/COG vs boat speed/heading is due to leeway and how much is due to current.

For now I'm just going to tie some wool to the stays and watch what the waves are doing.

Select to expand quote

Microbe said..

r13 said..

Microbe said..
If you are going down the route of hooking up an anemometer to a raspberry pie or similar it shouldn't be too much harder to add a magnetometer compass so you can calculate true wind. I wonder though, would you also need to include a boat speed sensor to allow you to account for any forward movement in your calculation?

Yes you will need boat speed to complete the triangle of boat speed, apparent wind speed and true wind speed;

sailzing.com/understanding-apparent-wind/

This link included leeway angle also;

www.starpath.com/freeware/truewind.pdf

Aha! Thanks R13 - that's some good info. And thanks Julesmoto for starting an interesting topic.

So all you'd need is a anemometer on the mast head to capture apparent wind speed and direction, an electronic compass to supply boat heading, a GPS to provide SOG and COG and a paddlewheel to get speed through the water. From that you can calculate true wind, leeway and current. Although I'm not sure how to work out how much the difference between SOG/COG vs boat speed/heading is due to leeway and how much is due to current.

For now I'm just going to tie some wool to the stays and watch what the waves are doing.

Funny last para. That's what I do on my 38 ATM coz my mast head instruments don't work. Need them for autopilot control by wind angle tho if desired. Also need them for wind direction if you are below decks on autopilot or at night sometimes.

Never have been able to see the point of wind speed apart from coming home and posting/bragging that I sailed in 40 knots plus. If it's getting a bit hairy or looks like becoming so then reef and if it's getting a bit slow shake a reef out.

www.bluebottlemarine.com/products/raymarine-wind-transmitter-battery-pack-seal.html#0

Doesn't seem too bad. About the same for the instrument battery.