Rhumb Runner - Course Provider plugin seems to ...
Course Provider plugin seems to have multiple errors in calculations for timeToGo, estimatedTimeOfArrival and distance... Got SKSim simulating data, got a course set in FreeboardSK and with me simulating at a fixed speed and course directly to the waypoint the TTG and ETA data coming back from the Course plugin is hours off. Also I'm seeing that the navigation.course.calcValues.distance from Course Provider and Derived Data's navigation.courseGreatCircle.nextPoint.distance are some 3000 meters different at 4nm from the waypoint. Even though the Course provider method of calculation is set for Great Circle. I'm simulating a distance of about 11 nm and a speed of 1 knot to start so the calcs should be very simple and any differences between great circle and rhumb line should be negligible. The time does seem to get closer and closer to being accurate as I simulate moving down the track but the ETA at a fixed speed I would think shouldn't change from the start of the simulation. Has anyone else seen this behavior? I haven't started diving into the code yet to see what derived data and course provider are doing differently. Any thoughts are appreciated...
2 Replies
I discovered why I was getting different distances. I believe it was related to Kip logins and had 2 different waypoints that I was navigating to at the same time? Cleared all routes while logged in as each user and re-setup the scenario. Still getting ETA and TTG values at fixed SOG's and headings to the waypoint that start off wildly wrong and gradually converge to being accurate in the last minute or so before reaching the waypoint. Haven't found where the Course Provider code is to look at it yet.
Plugin code is here https://github.com/SignalK/course-provider-plugin.
Calculations are done in
src/worker/coourse.ts