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Old 02-12-2012, 02:18   #256
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Whats happening to Cardahu (#19305)? VLM Status on_coast ?
I cannot see anny island around his position
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Old 02-12-2012, 03:09   #257
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Re: VENDÉE GLOBE round the world race

He probably made a mistake and is stuck upwind. He didnt hit any coast but because this is what happen when you do, vlm displays this message (wrongly)
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Old 02-12-2012, 05:12   #258
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Re: VENDÉE GLOBE round the world race

Maitai and Kirke are in great position. This morning I found a useful technique which you guys probably know about.

Use Non-Active pivoted Route to study Options.

Edit an Non-Active Route with pivot points, <Route><Edit> Uncheck "Hide intermediate POI".

Then just for fun go to Route Details Tab and set the Interval in the upper left to 120min to reduce the number of Route points generated. [-If the Route were Active would this affect path taken?]

Check the "Target POI" list" to see which intermediate POI's should appear on the chart now that "Hide intermediate POI" is unchecked. Close the Route now Route Tab / Ok and go to the chart window.

In the chart window grab the Intermediate POI (green boxes) [Shift+Right Mouse Button] and move then around and drop them where you want them [Release shift first]. Keep your eye on the Ending POI date to see when you're predicted to arrive and judge where to drop the Intermediate POIs.

You can move the End POI to change the route or extend it.

The optimal route between POI's that you have relocated will be redrawn instantly.

Using the Select or Now menu buttons you can study the progress of the boat and the weather conditions at a given time.

Comparing several routes in step progression is useful to understand options.

You can delete POIs to simplify the Route either individually Hover+ Right Click or using the Cursor Area Tool + right click.

Maitai, some questions. What is" Reckoning" [8] and "Vacs" [checked]?
Also what does setting the "Interval" in Route Details do to an actual route.
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Old 02-12-2012, 05:19   #259
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Re: VENDÉE GLOBE round the world race

One other question. In Route Settings > Autopilot "Load preselected POI's" Button. How do you use that option? How to I preselect a POI? Do I copy it? Then Paste into the window or hit "Load preselected POI" button?
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Old 02-12-2012, 05:27   #260
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Re: VENDÉE GLOBE round the world race

Just noticed that the fastest the boat (polar) can go is 26 knots in wind 30 knots, above that the boat goes slower and after 33 knots of wind the speed goes down in stages to 11 knots in 50 knots wind.

We can't use the middle of some of these VanGough's, need to play around the edges.
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Old 02-12-2012, 10:18   #261
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Re: VENDÉE GLOBE round the world race

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Originally Posted by rgleason View Post
One other question. In Route Settings > Autopilot "Load preselected POI's" Button. How do you use that option? How to I preselect a POI? Do I copy it? Then Paste into the window or hit "Load preselected POI" button?
That was a request by vlm committee, but it is not very useful imo. In fact you can right-click on a poi belonging to a route and choose "preselect for pilototo" or something like that. Then only these POIs will be sent to pilototo.

The interval param in the route's details is just to filter the list, for instance one hour by one hour, instead of 5/5 mn.

Reckoning is the length of your esteem. The small checkbox close to it has an tooltip help text. I can explain further if you need.
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Old 02-12-2012, 11:51   #262
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Re: VENDÉE GLOBE round the world race

Hello Maitai, without exploring the source code, how can I expand the "exploration angle" of the evaluated routes?

I have experimented with the Exploration coeff, alternate routes and the angular step and none seem to affect the spread of the explored routes.

I am trying to perform a test routing from Newport to Portsmouth, NH, and keep getting stuck south of the Cape Cod peninsula.

I'm thinking that QtVlm is just trying to enjoy a good downwind sail ;-)

Mike
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Old 02-12-2012, 19:07   #263
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Re: VENDÉE GLOBE round the world race

I have done a similar route up to Maine and qtVlm did successfully turn the corner and I was amazed. It was one of the first routings I had done. My suggestion is to move your boat location just a little and change you destination a little and try it.

But there is another way to do this. Make a <Route>. Then make four or five POI-1, POI-2,...POI-4. Then right click over each POI, pick Edit and assign it to the route, sequentially, pick the check box. Do this to each POI. Now hover over the POI, hit Shift + Left Mouse Button and move the poi where you want it. Then run a couple of Opimizations. You have to have the appropriate Grib file of the entire route with enough days. 8 days is probably enough.

Good luck. Maitai may chime in here if I have gone off course.
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Old 02-12-2012, 19:08   #264
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Re: VENDÉE GLOBE round the world race

When did WP9 East Aus Gate get moved? That was a surprize, but I guess Helmut called it earlier, like real race. Haven't even been watching the real race. What are the best links?
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Old 03-12-2012, 10:31   #265
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Re: VENDÉE GLOBE round the world race

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Originally Posted by rgleason View Post
I have done a similar route up to Maine and qtVlm did successfully turn the corner and I was amazed. It was one of the first routings I had done. My suggestion is to move your boat location just a little and change you destination a little and try it.

But there is another way to do this. Make a <Route>. Then make four or five POI-1, POI-2,...POI-4. Then right click over each POI, pick Edit and assign it to the route, sequentially, pick the check box. Do this to each POI. Now hover over the POI, hit Shift + Left Mouse Button and move the poi where you want it. Then run a couple of Opimizations. You have to have the appropriate Grib file of the entire route with enough days. 8 days is probably enough.

Good luck. Maitai may chime in here if I have gone off course.
Rick, I'm aware of that. What I wanted to do was see how I could twist the parameters in order to affect the exploration behavior of the router - I come from a semiconductor optimization background, and the problems are surprisingly similar, although wind direction is rarely a factor in that field ;-)

Mike
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Old 03-12-2012, 10:48   #266
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Re: VENDÉE GLOBE round the world race

The maximum research angle is 180. In fact the way it is designed the algorithm cannot go back, i.e. it discards all points that would end up farer than the origin isopoint (very roughly, it's a bit more complicated than that in fact ). btw I don't know of any routing software (such as Adrena pro for instance) that allows for more than 180 degrees.

In your situation you must do 2 routings. The first one to the cape and the second one as a "pivot-with-options" so you can change the target.
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Old 03-12-2012, 11:01   #267
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Re: VENDÉE GLOBE round the world race

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Originally Posted by maitai View Post
The maximum research angle is 180. In fact the way it is designed the algorithm cannot go back, i.e. it discards all points that would end up farer than the origin isopoint (very roughly, it's a bit more complicated than that in fact ). btw I don't know of any routing software (such as Adrena pro for instance) that allows for more than 180 degrees.

In your situation you must do 2 routings. The first one to the cape and the second one as a "pivot-with-options" so you can change the target.
I get what you're saying, but sometimes you have to backtrack in order to find an optimal route. 2 questions:

1) Any comment on my observation that the exploration coefficient, alternate routes values and exploration angles seemed to have no effect?

2) In which file is the code for the router? I have a few ideas...
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Old 03-12-2012, 12:32   #268
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Re: VENDÉE GLOBE round the world race

Rattus, sorry I had no idea you were an optimize expert. Perhaps you can help improve the algorithym a little? Since I am still learning how this program works, even more interesting to me is share some of your knowledge and approaches, perhaps they will lead to better things or understanding.

<Routing> <Advanced Tab>
More Options:
Prune Wake Angle (Exploration Angle) = (30) Maximum angle to test from the postion being calculated?
Exploration coefficient = (40) distance to search between two other POI? Idea being we don't want computer to be over exercised or computation to take too long.
Use Logarithmic Convergence towards Finish Checked -What is this?
Alternate Divergence:
Alternate Routes Number: (3) How many alternative routes to calculate
Divergence Threshold (%mini not commun): (75%) What does this mean.

Forecast Modification
Use this scenario Check
From this date [Enter date and time]
Wind strength is (90%) from Grib [Does this mean 90% of Grib strength?]
Offset grib forecast (0 hours).
Does this Offset grib forecast + /- then stretch the grib minute to minute, hour to hour, both in before the date and after the date by some interpolation?

Enough for now....
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Old 03-12-2012, 12:34   #269
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Re: VENDÉE GLOBE round the world race

Routing wants to go south, Gates are North and Gate WP9 moved north recently, requires many pivot points when doing long routings. Have not developed good understanding or methodology for this.
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Old 03-12-2012, 12:39   #270
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Re: VENDÉE GLOBE round the world race

The only way to avoid taking some real flyers in the future, after converting to a route and simplifying and optimizing, seems to be to do several <Routings> for affirmation, spread over a bit of time, (even a new grib). As time goes out it seems like the Routing can get a little extreme, when you run a new Route to the same location on the next updated grib about 6 hrs later, so you have to keep an eye on it!
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