Expedition Expedition Navigation Software

You are not logged in. Would you like to login or register?

1/24/2020 3:25 pm  #1

Choosing Grid and Isochrone resolution

I'm having great fun routing the Three Bridge Fiasco for tomorrow, where there are three marks about 7 miles apart in a rough triangle, in SFBAY. The course is go around all marks, cross the start/finish line at start and finish in either direction... https://imgur.com/a/IywuwuU

Question: where the wind and currents are notoriously variable, and the shoreline, islands, bridges, and exclusion zones make some of the available channels small, what is the effect of changing the grid size and time resolutions ?

Currently successful at 0.25 nm and 30 min. Not sure if there's any point in being that small, or would coarser not only run faster, but give equal optimization in a practical sense. 

Should those values be proportional to the expected Boat speed ? e.g if I am using 0.25 nm and go 4 kts, then should be at ~5 min time steps? 

The routing is coming out with 3-5 min steps already, which are incremental distances close to the grid.. 

Semiconductor Development Engineer, Retired Viticulturalist, Occasional sailor
"Lioness" 1962 Hinckley Bermuda 40 Custom Yawl

Board footera


Powered by Boardhost. Create a Free Forum

Interested in advertising here? Over a thousand active navigators and Expedition users visit this forum. Click here to contact the administrator.