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Old 15-11-2012, 14:44   #136
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Re: VENDÉE GLOBE round the world race

To simplify the Route waypoints, or avoid running over land:
Quote:
Before programming the autopilot you must avoid a route with a bold red track...deleting some of the POIs which are too close to land. After that you can do the normal procedure of programming the autopilot
To delete the "Intermediate POI's" you must have them showing. Go into " Routes / Edit Routes / Pick the route Then uncheck "Hide Intermediate POI's" also uncheck "Freeze Route" if that is checked. Then OK. Then you can see the Routes POI and right click / delete the appropriate ones.

There are several uses for this:
1. Reduce a long Route down to the six POI's accepted by the Autopilot "Send"
2. Simplify a route (with some time penalty) in order to avoid land.
3. Simplify a route to shorten it to possibly save time (provided the winds shift favorably or the change does not affect boat speed significantly)

Also you can skew an automatically drawn route by editing the POI's lat and long. This is done more automatically with the "Grib Esteem" tool (which I have not tried).
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Old 15-11-2012, 15:01   #137
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Re: VENDÉE GLOBE round the world race

Send specific waypoints to the Autopilot
Since we are on Route Intermediate way points, it is worth mentioning that there is a way to send a specific way point to the Autopilot, Right click on a waypoint with one of the green boxes and select "Mark --->WP; boat name" This will send the Mark to the boat's autopilot. - (I do not know if it just adds it to the list of waypoints in the autopilot -which is most likely - or if it points the boat immediately to that waypoint. Since I am racing I'm am not messing with it right now.

There are other interesting and useful commands such as:
"Optimize position on route"
"Not simplifiable" check
"Navigation mode VBVMG (very best VMG), BestVMG, Orthodronic
"Preset for autopilot" - Not sure what this does, have to find out.
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Old 15-11-2012, 15:11   #138
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Re: VENDÉE GLOBE round the world race

For Other Learners:

I have observed that using optimization can get somewhat fussy and too detailed for the kind of grib information available.

For example, in long distances, the last half of the trip, and even the last 80% of the trip is just an early test for routing. This portion should be more general and simplified with as few POI's as possible to allow the optimization to occur most freely between, as the conditions change. The location of the POI's should be at places that don't really change too much (ie where other routings seem to cross) or a headlands which must be passed without stranding, etc.

The first part of the Route tends to use the most current grib information and can be smaller in size for quick downloads and Routing checks. When converted to a Route, this more current portion of the trip can benefit from optimization and simplification, however, it may be useful to eliminate some POI's to simplify the route and allow the VBMG algorythm to use the most up to date information.

These are observations of a novice, so take them with a "large grain of salt", so to speak.
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Old 16-11-2012, 04:50   #139
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Re: VENDÉE GLOBE round the world race

Optimal routes:
Boat adjacent Est. speed 17.43 knts, est. heading 225.75 degrees.
My boat optimized shows 16.48 knots, heading 221.83 degrees.
I have 16.51 knots wind, he has 16.50 knots wind same direction 10.32 degrees.

He is supposed to be using the same polars. He just past me. What am I not doing here? A little further along, the "optimize route has me tacking for awhile. He is just heading down on a constant heading maybe?

I notice that according to the graphic polar, you can head down belowBest VMG wind Reaching 148.9 degrees and the boat speed looks a little faster from the graphic. How do I optimize to that?

I tried changing the VLM20 Wind Angle down under wind and actuallly he is heading up more than I am. When I make the Angle 145.1 the heading changes to 225.64 degrees and boat speed increases to 17.03 knots. I am going to go back to where I was on the optimal angle for reaching, which is 148.9 degrees. I am now wondering what others do and why. May variables here.
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Old 16-11-2012, 05:01   #140
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Re: VENDÉE GLOBE round the world race

I notice when I hit VLM Sync the angle goes back to 148.44 degrees rather than 148.9 degrees. This 148.44 deegree angle must be calculated by the optimization and results in the Very Best VMG of 16.15 knots, Boat Speed 16.45 knots in wind speed 16.48 knots.
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Old 16-11-2012, 11:56   #141
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Re: VENDÉE GLOBE round the world race

Another view of the fleet. Bib blue dots are for those who signed-up the OAD challenge (Once A Day, meaning they have the right to give orders only during one hour for each calendar day)
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Old 16-11-2012, 15:42   #142
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Re: VENDÉE GLOBE round the world race

Very interesting, OAD, however I am just learning and am unwilling to sign up for that. It's challenging enough keeping up, good luck to those who are willing to OAD. Have you signed up Maita?

Hartmut, I just got back and it appears that the weather gods have not smiled upon our side of the fleet and we will have many challenges ahead. Maitai and his crew are well ahead in my opinion, even though the Big Counter may think differently!

It's a long race anyway and there will be lots of frogs to jump in the future. Don't know if I can survive it the duration. Its addictive and difficult not to check and fiddle. It might be able to sign on to a TAD (Twice a Day) as a compromise with my dear mate, who is still asking where's the boat. (and I want to keep it that way!)

Congratulations Maitai, nice call.
Best
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Old 16-11-2012, 17:59   #143
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Re: VENDÉE GLOBE round the world race

At a point way south and west there appears to be about 85 nm difference, which of course will be very different in 8 days with expected changes in wind and weather, and differences in routes.
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Old 16-11-2012, 18:15   #144
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Re: VENDÉE GLOBE round the world race

Leaders are now off Dakar, following the coast - Pgen, Petite Mousse and Elrico
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Old 17-11-2012, 04:15   #145
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Re: VENDÉE GLOBE round the world race

Pgen, Elrico and Olonna are headed for Orango National Park, Gambia at the lead still and the surprise is that Pettite Mousse is headed our way in 11th. It appears a lot of new frontrunners have taken a southern loop down along the coast and then west, a successful routing indeed.

My route had almost run out when I awoke!
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Old 17-11-2012, 04:54   #146
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Re: VENDÉE GLOBE round the world race

Pgen has an excellent routing (we could have stuck with it Kirke and it would have been a Race). In the end I favored the heavier wind side with a big loop adding distance.
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Old 17-11-2012, 05:28   #147
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Re: VENDÉE GLOBE round the world race

More surprises to come for sure. Our best sailor is frogeater. You can count him on the podium, if not more. I have a mathematical relation(ship, lol) with this, he has more than that.
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Old 17-11-2012, 05:48   #148
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Re: VENDÉE GLOBE round the world race

I've noticed Frogeater. I don't understand your "mathematical" relationship with the podium or Frogeater? You are "on his heels", to use a colloquialism.
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Old 17-11-2012, 05:51   #149
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Re: VENDÉE GLOBE round the world race

I meant I have a mathematical relationship with routing and gribs and polars, obviously frogeater knows all this plus something that I don't know

Yet
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Old 17-11-2012, 06:17   #150
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Re: VENDÉE GLOBE round the world race

Is that why I am doing this? To learn more, get that sixth sense? Become a better sailor? I've got to start understanding the weather better, start tracking lows and highs which make the wind. As you can tell I'm looking for reasons to continue this entire race...and find a way to do it without it occupying too much of the day. Any suggestions? ....I need to keep 8 hours for other work, is a start. Check in in the middle.

Maybe it's 4 hour or 6 hour shifts and no more than 15 minutes on routing. -What to do at night? Anyway my dear mate is asking why I am so far behind now..54...
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