Facebook

Login

Support Sailonline

If you haven't already - join the SAILONLINE YACHT CLUB!

Please also consider making a donation - all amounts are greatly appreciated!

Board » Technical Discussion » Performance loss

Page: First Previous 7 8 9 10 11 12 13 Next

Posted by
kroppyer


Users avatar

Posts
347
Registered at
2010-02-05 15:25:55
2014-07-18 15:02:50 - Re: Performance loss
rod,

Starting at 100%, a loss of 8% is achieved by

With tack or gybe:
Tack to an angle that gives sog=16 kts, more speed is more performance loss. (the angle depends on polar and tws)

Without:
Turn 110 degrees. Greater angle is more performance loss.

For more complicated things (not starting with 100%, or doing more than one manouvre) please refer to the PDF I posted earlier in this thread.

--- Last Edited by kroppyer at 2014-07-18 15:04:28 ---
Posted by
dtayls


Users avatar

Posts
30
Registered at
2014-06-23 03:34:16
2014-08-15 04:30:08 - Re: Performance loss
Wow! Great thread. I've raced for almost 40 years and I'm an engineer & a computer scientist, so this one's right up my alley.

Having just read through the whole thread here are a few thoughts from me is not particular order:

1. SOL started with a realistic model and that should probably remain. Anything that breaks with realism should be explained, at the very least.

2. There are good real-world reasons for deaparting from the realistic model. Server load and reasonable sample rates need to be considered.

3. Different yachts recover differently so how you should sail each yacht should be different.

4. The world is changing quickly. Downwind-flyers come on and off the plane and their performance changes massively when this happens. If a boat is only just on the plane then a gybe will be costly.

5. And don't even talk about foiling and whether you can keep it up during a tack/gybe!!!

I suspect the SOL models are based on displacement vessels. It's probably time for an update particularly given that we're playing with some pretty impressive craft these days.
Posted by
dtayls


Users avatar

Posts
30
Registered at
2014-06-23 03:34:16
2014-08-15 06:24:08 - Re: Performance loss
I should also mention that I was impressed by some of the analytical work. Excellent stuff.

This reminds me of a marketing subject I did around 20 years ago at university. A key component was a computerized marketing strategy game.

In our group we analyzed the 'black box' of the game so well that after the results were published the lecturer bailed me up and accused me of cheating ...

Let me just say "I like your work."
Posted by
kroppyer


Users avatar

Posts
347
Registered at
2010-02-05 15:25:55
2014-08-15 09:45:59 - Re: Performance loss
I made this yesterday:
Sailonline Performance Calculator
http://sol.kroppyer.nl/performance/

It's about the same as the spreadsheet I posted earlier, but this one is more precise. Only time lost to next DC is not always accurate (because there is no clear definition for "time lost").

dtayls, funny that you read and posted on this thread just after I finished the calculator. Of course a new model would still be simplified reality, heavily simplified. But it's not hard to make a model that's more realistic than the current one, with the current model I fail to see the relation with reality.

You might see some worked out propositions for new models over here fairly soon.
Posted by
dtayls


Users avatar

Posts
30
Registered at
2014-06-23 03:34:16
2014-08-16 01:24:32 - Re: Performance loss
Kroppy,

Some SOLers are sailors while others are not.

It is probably true to say that most sailors want the model to be ultra-realistic while SOLers just want a model (aka. rules of the game) that they can understand and play against.

I personally think there is a middle ground that will probably work for everyone ... if implemented and explained properly.

The 15 second sample/update interval is an interesting aspect of the game. I am sure there are many reasons for this - server load and UI development requirements are just two that come to mind. But let's face it, this is not an online shoot-em-up game and people should probably not be trying to sail these things in real time. And if you want to play with a high performance yacht and really know how to tack/gybe on the plane/foil then get out on the water and do it IRL!

But that said, I think there is a lot of value to be had in changing some parts of the model and most of these are probably quite straight forward to implement.

Dtayls.
Posted by
HappyHour


Users avatar

Posts
27
Registered at
2009-01-08 06:48:51
2014-10-02 01:47:42 - Performance loss with high speed boats
A performance model hasnt to be realistic but it should work.
Our current model works with slow boats ( max speed 15kn ), of course far from perfect but it works.
It doesnt work well with faster boats (max speed 15+ kn).

With a AC72 it just gets crazy.
For example:
Gybe sailing downwind with 40kn speed at 92% performance, hurrah, no performance lost.
Doing the same at 94% performance, oops, performance drops to 74%.
Thats not just unrealistic. thats stupid!

Isnt the 93% rule outdated, a rule from history when the max speed was around 14kn?

Why dont we drop the 93% rule, let all performance calculations as it is and set hard limits, like max perf loss 90%.
Maybe even better:
Divide our fleet into "slow" and "fast" and set differrent max performance lost limits,
like 88% for the fast boats and 93% for the slow boats.
IMHO it should be possilbe to implement these changes to our server software.
Just an idea.
Posted by
kroppyer


Users avatar

Posts
347
Registered at
2010-02-05 15:25:55
2014-10-02 08:48:53 - Re: Performance loss
I fully agree that performance loss needs an update. To say the least

I really disagree on the idea that performance should be different across the fleet. First of all I like the beauty of everyone is exactly equal too much. Second, why would the people with less practise be faster in manoeuvres than the people with more practise?
[edit: I misunderstood the idea]

---
If it's going to happen, should we try a "do it once and to it good" approach, or should we spend some time on an intermediate performance system as "quick fix"?

--- Last Edited by kroppyer at 2014-10-02 15:55:39 ---
Posted by
HappyHour


Users avatar

Posts
27
Registered at
2009-01-08 06:48:51
2014-10-02 12:43:18 - Re: Performance loss
when i was talking about fleet, i didnt mean the boats in a single race.
I meant the diff between a "slow" yacht like first 40.7 and "Racing machines" like VO4 or our latest baby AC72.
Our fleet of available boats. From 6.5m upto 90m.

--- Last Edited by HappyHour at 2014-10-02 12:48:49 ---

--- Last Edited by HappyHour at 2014-10-02 14:04:02 ---

--- Last Edited by HappyHour at 2014-10-02 14:06:05 ---
Posted by
kroppyer


Users avatar

Posts
347
Registered at
2010-02-05 15:25:55
2014-10-02 15:54:33 - Re: Performance loss
Ah! I misunderstood. Now I fully agree: the performance system should depend on the boat type. A very simple solution would be as I described a few posts back and use the weight of a boat for the performance calculation.
Posted by
HappyHour


Users avatar

Posts
27
Registered at
2009-01-08 06:48:51
2014-10-07 15:56:46 - Re: Performance loss
"or should we spend some time on an intermediate performance system as "quick fix"?"

If some time means some hours, we should do the "quick and dirty fix". As i said in my previous posting, let all the calculations as it is and set a hard limit for the max. performance drop. that would at least eliminate the worst impacts of our current perf system.

Today i sailed 2 runs with a fast boat in the Atlantic Circle and tried to beat the performance drop system and it seems to work. A 3 step tacking, like from 45 twa to -5 twa, -20 twa and -45 twa may be faster then a normal tacking from 45 twa to -45 twa. The same with gybing. Gybe to the slowest possible speed to minimize the performance loss. Anything will be better than a 34kn speed to 34kn speed gybe with a 17% perf loss at 94% performance.

A nice tactical aspect, but im sure this isnt what the developers had in mind when they wrote our current code.


--- Last Edited by HappyHour at 2014-10-07 16:23:31 ---

Page: First Previous 7 8 9 10 11 12 13 Next

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Tall Ships 2026 - Antwerpen to Stavanger


Welcome to the third of four virtual Tall Ships Races in European waters which are concurrently being organized in-real-life by Sail Training International . This third race is from Antwerpen back up the North Sea to Stavanger in Norway – another proper tall ship training adventure of circa 450nm, online again in Sailonline’s classic Clipper 240.
NOTE: Starts and Finishes in tall ships racing are always offshore to avoid conflict with shipping and shipping lanes; online and real-life may not match exactly.
Race #1994
INFO by brainaid.de
Clipper 240 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: TSI - SUPBUD - SYC
Race starts: Jul 14th 16:00 Registration Open!
▶ Flash
GO TO RACE

Lake Ontario 300 Challenge 2026

Lake Ontario Offshore Racing (LOOR) welcomes Sailonline sailors to a second virtual version of a race in their annual series, and for the sixth year in succession the LO300. As the name implies, the LO300 is a 300nm offshore race across the length and breadth of Lake Ontario, from and back to Port Credit YC. This year, for the first time, we will be racing the 300nm circuit in Sun Fast 3200s. As usual, there is an overall prize for the SOLer who best bosses Lake Ontario over the two races hosted by Sailonline, this LO300 and the Susan Hood raced back in May, and this year also the race and the Susan Hood count towards the title of Super Buddy 2026; so, let the competition be fierce!
Race #2044
INFOby brainaid.de
Sun Fast 3200 PARTICULARS
NAM_AWIP WX Updates:
0245 / 0845 / 1445 / 2045
Ranking: LOOR - SUPBUD - SYC
Race starts: Jul 11th 15:10 Registration Open!

▶ Flash
GO TO RACE

Tall Ships 2026 - Harlingen to Antwerpen


Welcome to the second of four virtual Tall Ships Races in European waters which are concurrently being organized in-real-life by Sail Training International . This second race is from Harlingen in Friesland down along the coast of Holland and Friesland to Vlaanderen’s famous port of Antwerpen – circa 150nm in Sailonline’s classic Clipper 240.
NOTE: Starts and Finishes in tall ships racing are always offshore to avoid conflict with shipping and shipping lanes; online and real-life may not match exactly.
Race #1993
INFO by brainaid.de
Clipper 240 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: TSI - SUPBUD - SYC
Race starts: Jul 06th 16:00 Registration Closed
▶ Flash
GO TO RACE

Alaska to Easter Island 2026

Welcome to yet another all-new series. The initial leg of the RNW (Round the New World), Alaska to Easter Island, also part of our Ocean Championship. The first race of OCQ3 2026. This race will be sailed in our revised 'version 2' Imoca 60 Foil. Race #2042
INFO by brainaid.de
Imoca 60 Foil v2 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ3 - RNW - OCCH - SYC
Race starts: Jul 06th 11:00 Registration Closed
▶ Flash
GO TO RACE

Cross the Convergence 2026 - Sao Tomé to Tristan

The fifth race of our series of ocean voyages across the World’s convergence zones takes us back south down the Atlantic from Sao Tomé on the Equator to Tristan da Cunha on the edge of the Roaring Forties. It’s 2500nm; in your path the Benguela winds and current along the south west African coast, and behind that the St Helena High stretching halfway to South America. So, mind where you go in your Volvo OD65 version 3 (based on sampled real-life race data by kroppyer)!
Race #1985
INFOby brainaid.de
Volvo OD65v3 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: CCZ - SYC
Race starts: Jul 03rd 18:00 Registration Closed
▶ Flash
GO TO RACE

New Ice Age 2026 - Neumayer Station to Scott Base


For a second-half of long-distance ice-boating, we take our DNs to Antarctica for a circumnavigation of that continent in two legs clockwise, in harmony with the prevailing winds (such as there are), beginning with a race from Germany’s Neumayer Station to New Zealand’s Scott Base. It’s about 3500nm, which, if there’s wind at all, should, well-wrapped in your DN-cockpits, not take you much more than five days. And remember: charts down here are unreliable – what is land and what is ice?!
Race #1970
INFOby brainaid.de
DN PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: NIA - SYC
Race starts: Jul 02nd 07:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member WRmirekd
  2. Sailonline Yacht Club Member KaSToR
  3. Sailonline Yacht Club Member CriticalHippo
  4. Sailonline Yacht Club Member Panpyc
  5. Sailonline Yacht Club Member cdhinman
  6. Sailonline Yacht Club Member bonknhoot
  7. Sailonline Yacht Club Member rafa
  8. Sailonline Yacht Club Member CollegeFund
  9. Sailonline Yacht Club Member ms0689
  10. Sailonline Yacht Club Member rthinman

View full list

Series

Mobile Client

SYC members have the benefit of access to our mobile/lightweight web client!

The mobile client