Sonar Realism

[auknight]

Hey all! This is my first post, and I am relatively new to the subsim genre. My experiance is limited to Enigma: Rising Tide (sucks) and SH4, that's it!!

Anyway, I wanted to bring up the whole sonar/environmentals/detection thing. When I first started playing, I was curious how accurately sound propogation and such were modeled in this game. I read a few of the other threads related to the thermal layer.

Now, from my experience, I think there is no complex oceanographic modeling. There seems to be a simple implementation of a 'thermal layer' which I assume to be the sonic layer depth. When you pass this depth, the game simply tones down the sound your sub emits. In reality, the layer depth will quiet you significantly due to the fact that your props pretty much stop cavitating. You'd have to go much faster in order to cavitate at lower depths. The primary sound source for a sub running silent is the screws turning. I don't think subs back then had THAT many auxiliaries that could emit sound, other than the transients like the rudder, and dive planes moving, and I'm sure those were kept to a minimum.

So before I go further, what do the rest of you guys think? About ocean modeling, sonar detection, thermal layers, and the enemies ability to track you via passive/active sonar.

[ryu1940]

As a sonar tech, I wish there were more complex sound propagation models and dynamic ocean environments.

[Mush Martin]

in practice in the game the layer is simulated by programming
a dimiinishment of efficiency in the enemy sonar model so that
below a given depth they dont "see" that well how poorly can
be changed and at what depth can be changed as well as
detction range. surface clutter is also simulated in the game
code.

in reality in the US. campaign operational experience reduced
noise signatures almost 90 percent over pre war levels.

M

[SteamWake]

Yes the sound propigation models in SH series is vastly simplified. Shame but thats just the way it is.

They put there efforts into what to them (and others) felt were more important.

You sound guys might want to take a look at the sonalyist titles specifically Dangerous waters. It has a much more inticate sonar model.

[Rockin Robbins]

We begin with a simple non-quantified observation: when things are released into the air they fall to the ground.

They progress to intuitive speculation: it is obvious that the heavier an object is, the faster it must fall faster because of the greater force exerted on it.

At some point the intuitive speculation is confronted by a crisis: a bowling ball and a ping-pong ball are rolled down an inclined plane. They both arrive at the bottom simultaneously! WTF!!!!! (Why, That's Funny)

Now actual experimentation is done to measure this unexpected result and construct a mathematical model that will predict other analagous situations. When a method of making new predictions in order with the observed anomaly emerge, a new theory is born. Although it conforms with new observations, it may no longer solve old problems. It may not be grounded in truth, but only be an artificial construct that is useful for answering questions. Newton's law of gravity is one such analogy which in no way explains the reality of what is going on there.

This useful theory or paradigm continues until a new crisis emerges, requiring yet a new way of describing reality which answers a new set of questions.

Simulation progresses along the same line of wow this is great, I can do this to oh, shift I can't do that, to complete rewrite and new hardware back to the beginning. Each crisis results in a totally new underpinning of the simulation. But never will the simulation be reality. It will always be no more than a mathematical model, a mathematical description of reality. It will always have problems needing to be solved and problems that cannot be solved with the present paradigm.

OK, I'm finally done so everybody WAKE UP!!!!!!!

[auknight]

Thank you for the replies!

I also wanted to touch on tactics. I try to stick with tactics I think a real sub commander would use. To me, the primary concern is stay quiet and get the hell out of the area when being DC'ed after a torpedo run. I'm pretty sure due to simplified sound modeling, I can turn and dive all I want with no consequence. But I do believe turning your rudder and pumping water/relasing air for depth changes creates sound, thus increasing your probability of detection. Therefore, I usually go deep and stay at the same depth and course till I get out.

There's actually more to say, but didn't realize the time, and have to get to work. But feel free to let me know what you guys think tactics-wise till I get back!

[JSF]

RR....I swear, everytime I read one of your explanations I'm reminded of of my physics lectures in school....... Great reading and instruction...but I begin to get sweaty palms thinking about the exam that inevitably follows.......

[auknight]

Originally Posted by Rockin Robbins

We begin with a simple non-quantified observation: when things are released into the air they fall to the ground.

They progress to intuitive speculation: it is obvious that the heavier an object is, the faster it must fall faster because of the greater force exerted on it.

At some point the intuitive speculation is confronted by a crisis: a bowling ball and a ping-pong ball are rolled down an inclined plane. They both arrive at the bottom simultaneously! WTF!!!!! (Why, That's Funny)

Now actual experimentation is done to measure this unexpected result and construct a mathematical model that will predict other analagous situations. When a method of making new predictions in order with the observed anomaly emerge, a new theory is born. Although it conforms with new observations, it may no longer solve old problems. It may not be grounded in truth, but only be an artificial construct that is useful for answering questions. Newton's law of gravity is one such analogy which in no way explains the reality of what is going on there.

This useful theory or paradigm continues until a new crisis emerges, requiring yet a new way of describing reality which answers a new set of questions.

Simulation progresses along the same line of wow this is great, I can do this to oh, shift I can't do that, to complete rewrite and new hardware back to the beginning. Each crisis results in a totally new underpinning of the simulation. But never will the simulation be reality. It will always be no more than a mathematical model, a mathematical description of reality. It will always have problems needing to be solved and problems that cannot be solved with the present paradigm.

OK, I'm finally done so everybody WAKE UP!!!!!!!

Sorry, I'm not smart enough to understand a single word of your psycho babble. The way I see it, if someone has a problem with differentiating reality from a game or "simulation" that's THEIR issue, not yours. Myself, I know the difference between reality and fantasy, but I am curious just how "real" this particular aspect (sonar) is in this "game". That's it. If you have a problem with that, I'm sorry, I'll go crawl behind a rock and cry myself to sleep for having offended you in such a manner.

As far as mathematically modeling complex ocean environments, yeah, I don't see that happening in a game like this. I've used programs that generate sonar progation paths, basically using mathematical formulas to model sonar ranges based on user input. Knowing that it is possible, I also know it takes a LOT of input, and processing power to generate. However, just as in the game the thermal layer is simulated, how about under the layer, the detection range is significantly less than the surface layer? How hard is THAT to model? That's how it is in "reality". Or is that hoping for too much? Am I being too idealistic? Am I formulating new theories to match my desire for a specific outcome?

See, I thought these forums were open for people to talk about stuff related to, in this case, Silent Hunter 4. Should I not have started a discussion about sonar? Was it over the edge? Should we start pulling all threads that are considered "stupid questions"? My interest in sonar and USW/ASW tactics a no no for this forum?

Hey man, if you think people are delusional because they want to know just how "real" it can get, than feel free to stay away from this topic. It's as easy as that. It'll either start an interesting dialogue, or it will die. In the end, we still live our lives beyond Silent Hunter IV.

(Also, give me two months reading a thesaurus and I'll be able to edit this into $20 wording and sound very smart and sophisticated.)

[scrag]

It is a simple model and you are correct that it is a modeled layer depth which aids in evasion and detection. More of a model and the game would bog down. Even today we have extreme difficulty accurately modeling what sound does especially in shallow water and it has been my professional experience that even with the newer models and computers online for shipboard use they generally are good for sound paths but are horrendous at propagation loss. BTW I am also a Sonar Tech by trade 24 years worth.

[Joe Armstrong]

I would be happy with accurate turn counts and cone of sound modeling. Perhaps at some later date factoring in ocean modeling that would affect these two elements...

[Rockin Robbins]

Originally Posted by auknight

Sorry, I'm not smart enough to understand a single word of your psycho babble. The way I see it, if someone has a problem with differentiating reality from a game or "simulation" that's THEIR issue, not yours. Myself, I know the difference between reality and fantasy, but I am curious just how "real" this particular aspect (sonar) is in this "game". That's it. If you have a problem with that, I'm sorry, I'll go crawl behind a rock and cry myself to sleep for having offended you in such a manner.

As far as mathematically modeling complex ocean environments, yeah, I don't see that happening in a game like this. I've used programs that generate sonar progation paths, basically using mathematical formulas to model sonar ranges based on user input. Knowing that it is possible, I also know it takes a LOT of input, and processing power to generate. However, just as in the game the thermal layer is simulated, how about under the layer, the detection range is significantly less than the surface layer? How hard is THAT to model? That's how it is in "reality". Or is that hoping for too much? Am I being too idealistic? Am I formulating new theories to match my desire for a specific outcome?

See, I thought these forums were open for people to talk about stuff related to, in this case, Silent Hunter 4. Should I not have started a discussion about sonar? Was it over the edge? Should we start pulling all threads that are considered "stupid questions"? My interest in sonar and USW/ASW tactics a no no for this forum?

Hey man, if you think people are delusional because they want to know just how "real" it can get, than feel free to stay away from this topic. It's as easy as that. It'll either start an interesting dialogue, or it will die. In the end, we still live our lives beyond Silent Hunter IV.

(Also, give me two months reading a thesaurus and I'll be able to edit this into $20 wording and sound very smart and sophisticated.)

Sorry, but sonar techs get a far sight more technical than that! I guess I was looking to explain why sometimes we ask the devs for a feature and they say "can't do that." I don't remember being offensive, calling anybody "delusional" or saying that you asked a "stupid question." There's not a word of "psycho babble" in it. I just have no clue why your panties are in a wad at all.:hmm: I don't know what to do other than answer specific questions.

how about under the layer, the detection range is significantly less than the surface layer?

Yup. The volume of sounds heard and echoes from active sonar is less when you are under the thermal layer. Unlike RL, there is no refraction or reflection of sound waves.

That's how it is in "reality". Or is that hoping for too much?

There's more to it than that, but that simple generality is covered as I said above.

Or is that hoping for too much? Am I being too idealistic? Am I formulating new theories to match my desire for a specific outcome?

Please take some valium. I don't think there is any danger of these questions being true. But consider the source. Think I'll change my handle to "Psychobabbler."

Should we start pulling all threads that are considered "stupid questions"?

I think my position on "stupid questions" is well known. I won't repeat it here. You can search and find it.

My interest in sonar and USW/ASW tactics a no no for this forum?

There you go again, getting insecure. No, your interest in USW/ASW is a matter for the moderators to decide. But we have had lots of great conversation about sonar and USW/ASW tactics here without anybody going postal on us.

Hey man, if you think people are delusional because they want to know just how "real" it can get, than feel free to stay away from this topic.

Now you're a moderator. Congratulations.

Look. I just don't see how I was out of line. If a moderator decides, or people I respect on SUBSIM say I was, I'll just butt out of the conversation, but I'd say you've hijacked and killed your own thread here anyway.

[AVGWarhawk]

Originally Posted by auknight

Sorry, I'm not smart enough to understand a single word of your psycho babble. The way I see it, if someone has a problem with differentiating reality from a game or "simulation" that's THEIR issue, not yours. Myself, I know the difference between reality and fantasy, but I am curious just how "real" this particular aspect (sonar) is in this "game". That's it. If you have a problem with that, I'm sorry, I'll go crawl behind a rock and cry myself to sleep for having offended you in such a manner.

As far as mathematically modeling complex ocean environments, yeah, I don't see that happening in a game like this. I've used programs that generate sonar progation paths, basically using mathematical formulas to model sonar ranges based on user input. Knowing that it is possible, I also know it takes a LOT of input, and processing power to generate. However, just as in the game the thermal layer is simulated, how about under the layer, the detection range is significantly less than the surface layer? How hard is THAT to model? That's how it is in "reality". Or is that hoping for too much? Am I being too idealistic? Am I formulating new theories to match my desire for a specific outcome?

See, I thought these forums were open for people to talk about stuff related to, in this case, Silent Hunter 4. Should I not have started a discussion about sonar? Was it over the edge? Should we start pulling all threads that are considered "stupid questions"? My interest in sonar and USW/ASW tactics a no no for this forum?

Hey man, if you think people are delusional because they want to know just how "real" it can get, than feel free to stay away from this topic. It's as easy as that. It'll either start an interesting dialogue, or it will die. In the end, we still live our lives beyond Silent Hunter IV.

(Also, give me two months reading a thesaurus and I'll be able to edit this into $20 wording and sound very smart and sophisticated.)

In short, RR is saying it will always be a numbers game to create RL. Numbers sometimes can not do that. So, numbers are changed to get the best out of it as the program can do. Sonar is being worked on now by some of the modders to best simulate what was experienced in WW2 with 1940's equipment. It will never be dead on.


Oh, this is just how RR writes his usually long essays on why somethings work and do not work.

[Q3ark]

Originally Posted by AVGWarhawk

Oh, this is just how RR writes his usually long essays on why somethings work and do not work.

Yeah he's good, I like to read his rants (too strong a word?) but that post was way over my simple northern head

[Rockin Robbins]

Originally Posted by Q3ark

I like to read his rants (too strong a word?)

No some of my stuff IS rants, but I try to make 'em funny rants, especially the Admiral Lockwood posts. They're usually not my real position, just illustrating absurdity with absurdity and a little truth thrown in for seasoning.

I apologize if my earlier post was too hard to read. I'm still decompressing from reading Professor Thomas S Kuhn's "Structure of Scientific Revolutions." A Wikipedia link
This informal (for him) essay is a book written in scientific jargon, a foreign language similar to Icelandic. After you read it you speak a jangled mixture of English and Scientific for a couple of weeks until you regain your bearings.

One thing I won't ever do. I will never "dumb down" anything I say to spare the feelings of insecure people. I can't be any good to anybody if I'm not doing the best I can do. I do speak English and I will explain anything if you ask. The sonar guys can run circles around me in the details of sonar operation. My take is mostly philosophical, and that's intimidating to some people. It shouldn't be because it is a lot of fun.

There is no way that my intent is to make anybody feel stupid, make fun of questions asked. lecture anyone, I am making no dunce's caps to make anybody feel stupid. I have stong opinions sometimes, but they are always up for testing and subject to correction. I realize I can be overbearing sometimes and I just ask everyone to try to look beyond that bad habit and understand what I am saying. I'm just here having fun talking about a subject I love. Hope you're doing the same.

But darn, there are some good ideas in there and they're not mine so I can't take credit. Anybody curious at all?

[SteamWake]

Wow a good discussion on sonar digresses into a smoldering ember.