by admiral 1 » 21 Feb 2003 15:44
dial up
Port tack boat (P) and a Starboard tack boat (S) conferging on the same course coming abreast.
For all purposes only considering a situation with R10, R13 and R 16 are playing a role.
Based on R10 P has to stay clear, in such a way that S can change course without making immediate contact. The room S should have is then determined by the speed at wich S can change course and where it can go from there, within a timeframe that encompasses immediate.
Based on R 16 S can change course but must give P room to stay clear. P must be able to change course without making immediate contact.
When S changes course P gets a pen when immediate is over and a collison occurs, or for that matter can no longer be avoided.
stay clear
P may after immediate not be in an area where S can go within immediate. Even when in hindsight there would have been no contact ...
room to keep clear
S gets a Pen as soon as she enters the area P needed to change course to stay clear (at the time S started to change course) within immediate after S'es course change.
? define immediate: basically in real world measured by the commitee as they feel it might've been. Or a judge's feeling of what goes or might not go. Wind and water dependant. Mostly looked at only if someone protests. On the water without a commitee or a judge the more assertive skipper has most room, sometimes visibly comitting professional fouls... and then there's a basic 'understanding' of what goes and what doesn't ..... adopted by the sailors, the judges and or commitee. That can differ quite a lot from place to place, no matter how hard tried to define the rules explicitly.
? define course change: any eg. 0.5 degrees/ sec? don't even have to move the rudder to do that. 0.0000001/sec degrees would make holding course impossible. Course difference based on an average course over a certain time interval?
Any clue what the VSK judge is doing?
Objective: define parameters to control R10 and or R16 that will allow a dialup as you see it, and also a standard P vs S situation.
Make sure the algorithm (logic) is small enough to be computed every 50 ms? (framerate of 20/sec)
Anybody?
Theeuwes de Jong, skipper of Admiral
"As far as I can remember, there aren't a lot of points of land or holidays named after people who sat at home and criticized Christopher Columbus."
( Paul Cayard, from the Pirates base, in an e-mail to race HQ. 25 Jan 2006 volvooceanrace.org)