Hello Glen,

The tool we are developing does not yet produce polars from actual data.
However it does compare the actual data to a theoretical polar coming
from e.g. a IMS certificate.

I have been collecting data for half a year now, and found that the
fluctuations to the incoming data ("noise") affect the calculations very
much. We have therefore included extensive filtering capablities to get
reliable data to input into the polars.

The next step in the development is an analysing tool to go through the
collected data and establish a polar based on actual data.

Willem Amels


Glenn Ashmore wrote in
news:YSdgb.46915$sp2.44462@lakeread04:

While you guys are working on programs, I want to see one that
produces polars from actual data. Say you would set the sea state and
then when you get the boat really cooking you hit a button and it
records the wind data and boat speed. Then it would sort it all out
and plot polars for each sea state.

Another option would be to just constantly record the data and then
use peak boat speeds maintained for more than say 30 seconds to select
the points to plot.

It would be really interesting to invite a hotshot crew of racing
sailors to sail a boat and produce a set of polars then do the same
with your regular crew and try to match the results. It would be a
great way to refine sail trim and helm techniques.

Willem Amels wrote:
Hello Glen,




Hello,

We have a tool under development which graphs wind speed and
direction and much more. You can set the time span from 1 minute
until 16 hours and the program offers many options for filtering and
averaging the data.

If you combine it with a screen capture facility and automatic FTP it
may do the job for you.

You can download a 30 day trial version
at:
http://www.nauticis.com/download/supernova.rar


Willem Amels

On Mon, 06 Oct 2003 09:06:44 -0400, Glenn Ashmore
tempted fate with:

While you guys are working on programs, I want to see one that produces
polars from actual data. Say you would set the sea state and then when
you get the boat really cooking you hit a button and it records the wind
data and boat speed. Then it would sort it all out and plot polars for
each sea state.

Another option would be to just constantly record the data and then use
peak boat speeds maintained for more than say 30 seconds to select the
points to plot.

It would be really interesting to invite a hotshot crew of racing
sailors to sail a boat and produce a set of polars then do the same with
your regular crew and try to match the results. It would be a great way
to refine sail trim and helm techniques.

Glenn

Oddly enough, my cpRepeater program might be good start on this. The
current version captures all the data you want, including sea state.
It can export it as a CSV file easily imported into just about
anything. Based on your specs, I'd probably need to up the sample
frequency or else add the manual feature you mentioned. Unless you
can live with a 1 minute sample rate. The part I don't have is the
actual generation of polars. That's on the list to research as an
add-on someday. My gut feel is that filtering the data is tougher
than generating the polars. The manual approach you mention would
take that burden off me and put it on you, where it belongs. :-)
Adding the manual sample bit would be easy enough. Hmmm..



Glen "Wiley" Wilson usenet1 SPAMNIX at worldwidewiley dot com
To reply, lose the capitals and do the obvious.

Take a look at cpRepeater, an NMEA data integrator, repeater, and
logger at http://www.worldwidewiley.com/

To the original poster (sorry, the name escapes me at the moment) --

You might find this interesting.

http://www.siteplayer.com/

I have no knowledge of the product. It was pointed out to me by a
prospective customer who wants to use it to send NMEA data directly to
my program over ethernet, which should work.


Glen "Wiley" Wilson usenet1 SPAMNIX at worldwidewiley dot com
To reply, lose the capitals and do the obvious.

Take a look at cpRepeater, an NMEA data integrator, repeater, and
logger at http://www.worldwidewiley.com/

Glen Wilson wrote:

Oddly enough, my cpRepeater program might be good start on this. The
current version captures all the data you want, including sea state.
It can export it as a CSV file easily imported into just about
anything. Based on your specs, I'd probably need to up the sample
frequency or else add the manual feature you mentioned. Unless you
can live with a 1 minute sample rate. The part I don't have is the
actual generation of polars. That's on the list to research as an
add-on someday. My gut feel is that filtering the data is tougher
than generating the polars. The manual approach you mention would
take that burden off me and put it on you, where it belongs. :-)
Adding the manual sample bit would be easy enough. Hmmm..

The 30 seconds was just an arbitrary period to filter out surges due to
surfing etc. Manually picking the record point would be a problem
because if you are like me, when you really get the boat in the sweet
spot the last thing you think about is pushing a button! :-)

Analysis would be the real problem. First you would have to group by
sea state and wind speed to get a data set and sort by true wind angle
to get the polar coordinate then pick the highest normal boat speed to
get the vector length.

That last step would be the most complicated. Maybe look at everything
within 2.5º+ - of the true wind angle in 5º increments, throw out
everything below the median to eliminate acceleration and use the mode
or the upper standard deviation of the remaining values.

What I am after is not a theoretical value for boat performance from a
VPP but more the relative performance of the boat and crew together. I
would like to be able to gather data for several weeks and plot it out.
That could be used as a base line for tuning the boat and crew. Then
after a few months of working with the boat repeat the process and see
how much we have improved.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

On Sun, 05 Oct 2003 05:43:22 GMT, J wrote:

This is for a base station wind instrument which I'm putting together for a sailing club.
They have the NMEA instrument and have asked that I can put nice pretty graphs of wind
speed and direction up on their website. I'm thinking of just writing some code myself to
take the input and create a text file with it and have that FTP'd to their webspace and
run CGI scripts to graph it.

This might make it a bit clearer!
I hope

The Jericho Sailing Center (Vancouver, BC) does this - see
http://www.jerichowind.com/ and http://www.jsca.bc.ca/

Perhaps someone there can tell you how they do it.



--
Peter Bennett, VE7CEI
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca

Not quite so easy, Glenn. I race as navigator and pit on a Jenneau
Selection 37 that is now one of the top boats in Massachusetts. It
took us five years racing three or four days a week to get the boat
dialed in -- maybe we're just dumb, but our present record suggests
otherwise. So if you want to invite us down for a year or two -- your
expense, of course ;-)

As far as recording polars goes, the package I've sent to two of the
posters here, following up on my earlier offer in this thread, will
automatically log all you need for polars with very little
modification. You would need to be comfortable with Visual Basic.

You don't really need polars, however, as all you have to do is sail
for the best VMG on your GPS. This suggests that you have someone
aboard who knows how to pull the strings just right.

Many cruisers could benefit from a season or two of racing on a
serious boat -- I certainly did. Since boats in the 30-40' range
carry crews of 8-10 people, there is often an opening for one or two
novices who may be nothing but movable ballst for almost the whole
race. Try your local yacht club.

Jim Woodward
www.mvFintry.com

Glenn Ashmore wrote in message news:YSdgb.46915$sp2.44462@lakeread04...
While you guys are working on programs, I want to see one that produces
polars from actual data. Say you would set the sea state and then when
you get the boat really cooking you hit a button and it records the wind
data and boat speed. Then it would sort it all out and plot polars for
each sea state.

Another option would be to just constantly record the data and then use
peak boat speeds maintained for more than say 30 seconds to select the
points to plot.

It would be really interesting to invite a hotshot crew of racing
sailors to sail a boat and produce a set of polars then do the same with
your regular crew and try to match the results. It would be a great way
to refine sail trim and helm techniques.

Willem Amels wrote:

Hello,

We have a tool under development which graphs wind speed and direction and
much more. You can set the time span from 1 minute until 16 hours and the
program offers many options for filtering and averaging the data.

If you combine it with a screen capture facility and automatic FTP it may
do the job for you.

You can download a 30 day trial version
at:
http://www.nauticis.com/download/supernova.rar


Willem Amels

On Mon, 06 Oct 2003 10:37:21 -0700, Peter Bennett
wrote:

On Sun, 05 Oct 2003 05:43:22 GMT, J wrote:

This is for a base station wind instrument which I'm putting together for a sailing club.
They have the NMEA instrument and have asked that I can put nice pretty graphs of wind
speed and direction up on their website. I'm thinking of just writing some code myself to
take the input and create a text file with it and have that FTP'd to their webspace and
run CGI scripts to graph it.

This might make it a bit clearer!
I hope

The Jericho Sailing Center (Vancouver, BC) does this - see
http://www.jerichowind.com/ and http://www.jsca.bc.ca/

Perhaps someone there can tell you how they do it.

I've done some work with this setup....

http://www.aag.com.mx/weather.html

There are various softwares out there that give all the data you may
ever need....

On Mon, 06 Oct 2003 20:35:34 -0400, No One Home
wrote:

On Mon, 06 Oct 2003 10:37:21 -0700, Peter Bennett
wrote:

On Sun, 05 Oct 2003 05:43:22 GMT, J wrote:

This is for a base station wind instrument which I'm putting together for a sailing club.
They have the NMEA instrument and have asked that I can put nice pretty graphs of wind
speed and direction up on their website. I'm thinking of just writing some code myself to
take the input and create a text file with it and have that FTP'd to their webspace and
run CGI scripts to graph it.

This might make it a bit clearer!
I hope

The Jericho Sailing Center (Vancouver, BC) does this - see
http://www.jerichowind.com/ and http://www.jsca.bc.ca/

Perhaps someone there can tell you how they do it.

I've done some work with this setup....

http://www.aag.com.mx/weather.html

There are various softwares out there that give all the data you may
ever need....


Sorry, I assumed there was loads of software behind the link "free
software"

try looking at:

http://www.aagelectronica.com/aag/index.html

I'm partial to Arne's work,

http://weather.henriksens.net/

but there are others that will work just as well.
---

"Maurice Wick is a fine human being, and the best teacher I have ever had..." ---Dan Larsen

On Mon, 06 Oct 2003 20:35:34 -0400, No One Home
wrote:

On Mon, 06 Oct 2003 10:37:21 -0700, Peter Bennett
wrote:

On Sun, 05 Oct 2003 05:43:22 GMT, J wrote:

This is for a base station wind instrument which I'm putting together for a sailing club.
They have the NMEA instrument and have asked that I can put nice pretty graphs of wind
speed and direction up on their website. I'm thinking of just writing some code myself to
take the input and create a text file with it and have that FTP'd to their webspace and
run CGI scripts to graph it.

This might make it a bit clearer!
I hope

The Jericho Sailing Center (Vancouver, BC) does this - see
http://www.jerichowind.com/ and http://www.jsca.bc.ca/

Perhaps someone there can tell you how they do it.

I've done some work with this setup....

http://www.aag.com.mx/weather.html

There are various softwares out there that give all the data you may
ever need....


Sorry, I assumed there was loads of software behind the link "free
software"

try looking at:

http://www.aagelectronica.com/aag/index.html

I'm partial to Arne's work,

http://weather.henriksens.net/

but there are others that will work just as well.

J wrote:
I am curious about what IMS data provides. I know it comes from the IMS
vpp but how much info is given on you ims certificate. Is it similar to
polar data that could be used in navigation software. We have very
limited polar data for our boat and I would like to increase the range and
accuracy of it.

Thanks


Hi,

Does anyone know of some software to log and graph windspeed and direction from a NMEA
wind instrument??

I would also like to have the ability to store the image of the graph as a JPG or similar
file, as well as control over the logging.

Cheers
J