[WIP] Hydrophone Tracker/Quick Plotter

[jmr]

Ironing out the bugs I take it?

[gutted]

Actually no, its working as intended.

But im thinking of redisnging it after some input from kylania. .ie instead of inputting them into text boxes you draw them out, with little drag handles so you can move them around.

Also im going to add support for any number of sightings.. becase as it is right now, the accuracy depends entirely on how "correct" your 3 sightings are. Being 1 degree off can skew the results. So if instead you use 4 bearings, it will grab the course of the first 3 & last 3 and then average them out. If you add another one.. it will refine it even more etc.

I was getting pretty decent results from it (within 5 degree course), but i knew the tolerances and was carefully listening. Kylania on the other hand didn't realize this, and he didn't get the intended course.

If you are interested in using this initial test version.. i guess i can upload it as is.. but you just need to keep in mind that with only 3 bearings... theres not much fudge factor and it should only be used as an estimate.

My advice would be to open two instances of the app and take 4 bearings. Enter the first 3 in one window, and enter the last 3 in the other window, and compare the two courses.

[Takeda Shingen]

Moved to appropriate forum.

The Management

[Nico71]

You mean, I don't need to check every hour again to see if it's finally available?

Call me a nerd or whatever, but somehow this TMA stuff got me hooked!

[gutted]

Ok you can test it out:
http://www.subsim.com/radioroom/down...o=file&id=1699

Just keep in mind that im working on a more robust version. Both in the computed solution and UI friendliness.


Also: a few things have changed since the screenshots posted. The range scale at the top left is gone, the display is no longer zoomable with the mousewheel. The red line doesn't turn solid and move to its correct range once you input it. Displaying it at the correct range was a useless feature, and only forced you to zoom in and out. Instead the lines will scale to fit the bearing wheel.



kylania:
You might wanna redownload it, i made two small updates to it since your copy.

1. The lines are anti-aliased now.
2. The predicted bearing and estimated course readouts are not rounded anymore.

[gutted]

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]

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

Just use a smaller interval due to the closer ranges.

[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?

[gutted]

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]

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]

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]

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]

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.

[gutted]

Ok let me get this straight to make sure we are thinking the same.


Lets say you are heading 30 degrees at 5kts.

You plot the three bearings on that static board and get a relative course.

But since you dont yet know the range, you have no way of knowing the relative speed of the target, and thus cannot do the vector cacluation to transform the relative course to a true course and speed.

So... you turn and triangulate the 4th bearing to get the range. Then input that on that board.

It can now caclulate the targets relative speed from that range... and using your heading and speed (which you didn't change when you turned away), it can compute the true course and speed.



did i get that right?

.ie You turn and or change speed to triangulate the predicted bearing... but you leave your original course and speed unchanged on the board?

[kylania]

One other thing I'd add is a GIANT PULSING LETTERS with trumpet fanfare saying "Draw bearing #4 on the map before you move!"

I've so far forgotten to 4 out of 5 times.

Also, this thread has a nice PDF that explains a lot of the methods used here, including moving various speeds to get a course:

http://www.subsim.com/radioroom/showthread.php?t=160817