[WIP] Hydrophone Tracker/Quick Plotter

gutted · 04-02-10, 10:10 AM

Dude, why the hell did you move the thread here?

It's not a mod.

Now you're going to have all sorts of people jumping in here thinking i made something to drop into their game.

gutted · 04-02-10, 10:36 AM

One last tidbit.. you can do with the scope as well.

Just use a smaller interval due to the closer ranges.

Nico71 · 04-02-10, 10:41 AM

It's useful for stalking prey at very long distance. Which leads me to the next question: will you support TMA while moving as well?

gutted · 04-02-10, 11:02 AM

Started redisnging it.. got the drag handles drawing (though they dont drag yet hehe). Also made the middle area of the bearing wheel fainter. Bearing lines will be thinner as well (not shown).

gutted · 04-02-10, 11:11 AM

Quote:

Originally Posted by Nico71

It's useful for stalking prey at very long distance. Which leads me to the next question: will you support TMA while moving as well?

Without a range for each bearing .. how would you convert the target's direction of relative of movement (DRM) to an actual course if you dont know it's relative speed?

I just dont see it happening from a static manuevering board type display.

Nico71 · 04-02-10, 11:47 AM

Quote:

Originally Posted by gutted

Without a range for each bearing .. how would you convert the target's direction of relative of movement (DRM) to an actual course if you dont know it's relative speed?

I just dont see it happening from a static manuevering board type display.

Hmmm, I think what I had in mind was something along those lines (excuse the pun!

):

http://www.subsim.com/radioroom/show...50&postcount=2

Especially the last part about relative motion and speed and course vector to obtain true motion. Just with automatic calculation of the latter. I don't know if this is feasible, hence my question.

gutted · 04-02-10, 12:00 PM

In that example he had to guess at what the range was to get an estimate of the targets speed on the reatlive track.

Without a "sonar ping" in a Uboat, how do you intend to get this range?

And like i said, without an estimate of the target's speed on the "relative track" you can't convert it to a true course and speed.

Nico71 · 04-02-10, 12:17 PM

That's indeed a tricky one, as there is no course change in the example. But we have a cross bearing, thus getting more or less precise results. Just relative in this case. Then do the vector calculation using initial (!) OS speed and course and the end result target data.

Not sure if we are on the same page, though.

Pisces · 04-02-10, 01:25 PM

If you want to do it moving you need 2 sets of 3 bearings as you need to make a significant course and/or speed change in between to alter the relative motion. And both 'target courses' need to be translated to the head of your own speedvectors. Where they cross is the endpoint of the actual target course and speed vector.

Read here:

http://www.filefront.com/13598315/bearingsonly_TMA.pdf

Also, for better accuracy in course, just take longer periods between the bearings. Waiting for 4 degrees bearing change is really too short. I guess you could average it out like that (first three bearings and last three bearings out of a set of 4), but it still has a large margin of error which doesn't go away doing that. You think the bearing is exact when it is reported, but it could be a full degree of. So the difference between 2 bearings has a total margin of error of 2 degrees.But since this method depends on 2 bearing differences the margin of error doubles again. Compare the following bearing sets:

B1=11, B2=15, B3=22, which makes target course 177
(from the original post example)

B1=11.00, B2=15.99, B3=22.00, which makes target course 150
B1=11.99, B2=15.00, B3=22.99, which makes target course 186

186-150=36 degrees margin of error.

I'm not too happy about that!

Yes, that can utlimately happen if you rely on crew reports that are not taken when the bearing crosses the exact degree.

Now lets say you wait longer, like until bearing has moved 7 degrees:

B1=11, B2=18, B3=37, which makes target course 177.1 (our reference)

Then taking worst case margins of error:

B1=11, B2=18.99, B3=37.00, which makes target course 173
B1=11.99, B2=18, B3=37.99, which makes target course 182

182-173=9

Much better, and if you do the math (which I'll spare you) those 7 degrees only took 50% longer, so 22 an a halve minutes per interval.

04-02-10, 10:10 AM	#1
gutted The Old Man Join Date: Apr 2005 Location: New Orleans, LA. Posts: 1,379 Downloads: 487 Uploads: 11	Dude, why the hell did you move the thread here? It's not a mod. Now you're going to have all sorts of people jumping in here thinking i made something to drop into their game. __________________ Solution Solver 2.3.2 - Visual Targeting Tools & Aids

04-02-10, 10:36 AM	#2
gutted The Old Man Join Date: Apr 2005 Location: New Orleans, LA. Posts: 1,379 Downloads: 487 Uploads: 11	One last tidbit.. you can do with the scope as well. Just use a smaller interval due to the closer ranges. __________________ Solution Solver 2.3.2 - Visual Targeting Tools & Aids

04-02-10, 11:02 AM	#4
gutted The Old Man Join Date: Apr 2005 Location: New Orleans, LA. Posts: 1,379 Downloads: 487 Uploads: 11	Started redisnging it.. got the drag handles drawing (though they dont drag yet hehe). Also made the middle area of the bearing wheel fainter. Bearing lines will be thinner as well (not shown). __________________ Solution Solver 2.3.2 - Visual Targeting Tools & Aids Last edited by gutted; 04-02-10 at 11:26 AM.

04-02-10, 12:00 PM	#7
gutted The Old Man Join Date: Apr 2005 Location: New Orleans, LA. Posts: 1,379 Downloads: 487 Uploads: 11	In that example he had to guess at what the range was to get an estimate of the targets speed on the reatlive track. Without a "sonar ping" in a Uboat, how do you intend to get this range? And like i said, without an estimate of the target's speed on the "relative track" you can't convert it to a true course and speed. __________________ Solution Solver 2.3.2 - Visual Targeting Tools & Aids

04-02-10, 01:25 PM	#9
Pisces Silent Hunter Join Date: Dec 2004 Location: AN9771 Posts: 4,904 Downloads: 304 Uploads: 0	If you want to do it moving you need 2 sets of 3 bearings as you need to make a significant course and/or speed change in between to alter the relative motion. And both 'target courses' need to be translated to the head of your own speedvectors. Where they cross is the endpoint of the actual target course and speed vector. Read here: http://www.filefront.com/13598315/bearingsonly_TMA.pdf Also, for better accuracy in course, just take longer periods between the bearings. Waiting for 4 degrees bearing change is really too short. I guess you could average it out like that (first three bearings and last three bearings out of a set of 4), but it still has a large margin of error which doesn't go away doing that. You think the bearing is exact when it is reported, but it could be a full degree of. So the difference between 2 bearings has a total margin of error of 2 degrees.But since this method depends on 2 bearing differences the margin of error doubles again. Compare the following bearing sets: B1=11, B2=15, B3=22, which makes target course 177 (from the original post example) B1=11.00, B2=15.99, B3=22.00, which makes target course 150 B1=11.99, B2=15.00, B3=22.99, which makes target course 186 186-150=36 degrees margin of error. I'm not too happy about that! Yes, that can utlimately happen if you rely on crew reports that are not taken when the bearing crosses the exact degree. Now lets say you wait longer, like until bearing has moved 7 degrees: B1=11, B2=18, B3=37, which makes target course 177.1 (our reference) Then taking worst case margins of error: B1=11, B2=18.99, B3=37.00, which makes target course 173 B1=11.99, B2=18, B3=37.99, which makes target course 182 182-173=9 Much better, and if you do the math (which I'll spare you) those 7 degrees only took 50% longer, so 22 an a halve minutes per interval. __________________ My site downloads: https://ricojansen.nl/downloads

04-02-10, 10:41 AM	#3
Nico71 Medic Join Date: Sep 2001 Location: Germany Posts: 168 Downloads: 145 Uploads: 0	It's useful for stalking prey at very long distance. Which leads me to the next question: will you support TMA while moving as well?

04-02-10, 12:17 PM	#8
Nico71 Medic Join Date: Sep 2001 Location: Germany Posts: 168 Downloads: 145 Uploads: 0	That's indeed a tricky one, as there is no course change in the example. But we have a cross bearing, thus getting more or less precise results. Just relative in this case. Then do the vector calculation using initial (!) OS speed and course and the end result target data. Not sure if we are on the same page, though.