AI sonar effectiveness

zed055 · 07-27-11, 09:53 AM

I have a question regarding the detection capabilities of AI-controlled units:

If, while in shallow water (under 150ft), the player sub is resting on the bottom, does this reduce the chance of detection for the surface units? My understanding of active sonar is that, if a target is resting on the bottom in moderate clutter, active sonar effectiveness is significantly decreased. Is this true and, if so, is this modelled into the program?

Currently running stock 1.4 without mods. Only been using the program for a few weeks, and I'd like to get a handle on the vanilla game before I start changing stuff.

Thanks!

Armistead · 07-27-11, 10:23 AM

Not in the game and unable to mod such. In fact, sitting on the bottom will eventually cause damage, it's like running into land.

zed055 · 07-27-11, 11:14 AM

Quote:

Originally Posted by Armistead

In fact, sitting on the bottom will eventually cause damage, it's like running into land.

While I haven't performed extensive testing in-game, I bottomed the Tambor-class USS Gar (SS-206) repeatedly attemping to evade a subchaser off Osaka (insert operative at Osaka mission). No damage resulted - which makes sense, since bottoming a submarine frequently happened during operations during WWII (http://goo.gl/aSrNX) in shallow waters. A modern SS(N) can't do it for various reasons, but the old boats could.

Ducimus · 07-27-11, 01:15 PM

If you drift onto the bottom you wont take any damage. By drifting i mean lowering your depth, without forward propulsion. All stop, zero speed, dive planes set to go deeper then the bottom really is.

But no.. bottoming the boat will NOT help you. The only time laying doggo on the bottom is helpful, is if your about to enter a shallow water area, and your just waiting for night time to do it.

Armistead · 07-27-11, 01:48 PM

Duci explained better, if I sit at the bottom actually touching land so that it rubs, even at 0, given enough time you can get minor damage, but never more than a few percent, you drag bottom with any speed damage will increase.

Some use a minor glitch, if you set 0 speed, planes to go deeper than the bottoms actual depth, you won't take any damage at all.

Still, you get no sonar effect hiding from sitting on the bottom in the game.

Course in a crash out of control dive due to damage, I would rather hit bottom than head for the deep.

Daniel Prates · 07-27-11, 05:15 PM

It is my guess that active sonar will simply hit you and bounce back, regardless of you being in the bottom or not. Shouldn't make any difference towards detection.

Ducimus · 07-28-11, 11:55 AM

Active sonar in SH3, 4 and 5, is much like a flashlight beam.

It's always on, in a fixed width, and angle.

If it see's you are not depends on how much of your subs surface area is exposed to the flashlight beam, and for how long its exposed.

TorpX · 07-28-11, 09:43 PM

A question Ducimus:

If enemy escorts are alerted and searching for you, but you are not detectable at the moment, for whatever reason ( below thermal layer, etc.), will they ever go off and chase false echos?

Rockin Robbins · 07-29-11, 07:16 AM

I believe there are no false echoes in SH4. If you are not presently detected, escorts circle the point of last contact. If contact is not reacquired in 30 minutes they leave and resume escort duties..

Actually that is the basis of my convoy attack strategy of attacking from one side of the convoy and shooting from long enough range (between 1500 and 2000 yards) on the first shot to turn tail and run away. The escorts come from both sides of the convoy to kill me but I've already turned tail and am out of there.

They will circle for a half hour, giving me time to do an end around to attack the weakly guarded side of the convoy. This time I'm getting in close and doing some guaranteed big time damage. Then I pull out and end around to the other side for my next attack.

I've stripped entire convoys of their merchies that way and left the escorts to just steam away because they have no one to escort.

EricW · 07-29-11, 08:43 AM

Quote:

Originally Posted by Rockin Robbins

I believe there are no false echoes in SH4. If you are not presently detected, escorts circle the point of last contact. If contact is not reacquired in 30 minutes they leave and resume escort duties..

Actually that is the basis of my convoy attack strategy of attacking from one side of the convoy and shooting from long enough range (between 1500 and 2000 yards) on the first shot to turn tail and run away. The escorts come from both sides of the convoy to kill me but I've already turned tail and am out of there.

They will circle for a half hour, giving me time to do an end around to attack the weakly guarded side of the convoy. This time I'm getting in close and doing some guaranteed big time damage. Then I pull out and end around to the other side for my next attack.

I've stripped entire convoys of their merchies that way and left the escorts to just steam away because they have no one to escort.

This works......over and over.
Once you get the escorts to key in on one spot and you successfully get away from that spot, you have free rein to set up your REAL attack.

Daniel Prates · 07-29-11, 08:44 AM

Quote:

Originally Posted by Rockin Robbins

I've stripped entire convoys of their merchies that way and left the escorts to just steam away because they have no one to escort.

Cool, you kinda forced them to go 'tokyo express'. But with no load. That oughta show them.

I think that DD search patterns change a lot between different mods. I've seen them chase you for hours in some ocasions, they won't necessarily drop you after 30 minutes without a contact.

Probably there are a lot of varaibles here. Are there enough DDs to spare the chase as the others remain with the convoy? Are there not? Is he getting signals from you every now and then, or have you disapeared completely? I think different situations will cause different DD behaviour.

TorpX · 07-31-11, 12:14 AM

Quote:

Originally Posted by Rockin Robbins

I believe there are no false echoes in SH4. If you are not presently detected, escorts circle the point of last contact. If contact is not reacquired in 30 minutes they leave and resume escort duties..

I was afraid of that.

Quote:

I've stripped entire convoys of their merchies that way and left the escorts to just steam away because they have no one to escort.

He he, sounds good.

I am reminded though, of a situation the happened to O'Kane, where he sank all the merchents in a small convoy and was left with the sole escort DD. He considered that it was more dangerous, now that it was alone, and had no sheep to shepard, if you get my drift. It could devote it's full attention to exacting revenge for the losses.

Quote:

I think that DD search patterns change a lot between different mods. I've seen them chase you for hours in some ocasions, they won't necessarily drop you after 30 minutes without a contact.

Probably there are a lot of varaibles here. Are there enough DDs to spare the chase as the others remain with the convoy? Are there not? Is he getting signals from you every now and then, or have you disapeared completely? I think different situations will cause different DD behaviour.

This is what I don't get. Duci's DD's in TMO are famous for being tough, but unless I misinterpreted what he posted, all escort behavior is hardcoded and unchangable, apart from crew ratings. He also implied that much of this (in the game) is oversimplified.

Daniel Prates · 08-02-11, 08:47 AM

Quote:

Originally Posted by TorpX

This is what I don't get. Duci's DD's in TMO are famous for being tough, but unless I misinterpreted what he posted, all escort behavior is hardcoded and unchangable, apart from crew ratings. He also implied that much of this (in the game) is oversimplified.

Maybe it is like that Asimov tale where a robot gets a '3-laws' conflict (helping men and not destroing himself) and eventually keeps running in circles around a mineral deposit, without knowing what to do!

Get the picture? DD has a pattern to follow. After loosing contact for some time, he will give up, but may get contact again, then loose it... the time interval between contacts may result in a hard-to-understand behaviour pattern, that appears to conflict with the known hardcoded behaviour.

Or maybe I've been reading Asimov too much.

Armistead · 08-02-11, 09:06 AM

The main thing is once you lose contact with a DD, don't do something stupid until you've got some range on them. Very important with cams off.
You may finally escape the circle, but they could still be hunting where they last had contact with you, if you increase speed, come up above the thermal, cut off silent running, one could hear and the whole herd could come back. It's also common for them to leave a sleeper behind stopped, so you get no sonar contact. Make sure you clear the baffles several times.

I've set most of mine to elite status and they hunt you like dogs, sometimes the only thing I can do is wait for them to run out of charges.

WernherVonTrapp · 08-02-11, 09:48 AM

Welcome abroad zed055.

Now I have a question. I've noticed while traversing the (I think) Yellow Sea that there are a lot of deep and rather thin slit trenches found in the shallows. Some are very deep and barely wider than my boat. Would hiding in the depths of one of these trenches have any effect whatsoever on the enemy's active sonar?

07-27-11, 09:53 AM	#1
zed055 Nub Join Date: Jul 2011 Location: Canada Posts: 4 Downloads: 2 Uploads: 0	AI sonar effectiveness I have a question regarding the detection capabilities of AI-controlled units: If, while in shallow water (under 150ft), the player sub is resting on the bottom, does this reduce the chance of detection for the surface units? My understanding of active sonar is that, if a target is resting on the bottom in moderate clutter, active sonar effectiveness is significantly decreased. Is this true and, if so, is this modelled into the program? Currently running stock 1.4 without mods. Only been using the program for a few weeks, and I'd like to get a handle on the vanilla game before I start changing stuff. Thanks!

07-28-11, 09:43 PM	#8
TorpX Silent Hunter Join Date: Sep 2010 Posts: 3,975 Downloads: 153 Uploads: 11	A question Ducimus: If enemy escorts are alerted and searching for you, but you are not detectable at the moment, for whatever reason ( below thermal layer, etc.), will they ever go off and chase false echos?

07-29-11, 07:16 AM	#9
Rockin Robbins Navy Seal Join Date: Mar 2007 Location: DeLand, FL Posts: 8,900 Downloads: 135 Uploads: 52	I believe there are no false echoes in SH4. If you are not presently detected, escorts circle the point of last contact. If contact is not reacquired in 30 minutes they leave and resume escort duties.. Actually that is the basis of my convoy attack strategy of attacking from one side of the convoy and shooting from long enough range (between 1500 and 2000 yards) on the first shot to turn tail and run away. The escorts come from both sides of the convoy to kill me but I've already turned tail and am out of there. They will circle for a half hour, giving me time to do an end around to attack the weakly guarded side of the convoy. This time I'm getting in close and doing some guaranteed big time damage. Then I pull out and end around to the other side for my next attack. I've stripped entire convoys of their merchies that way and left the escorts to just steam away because they have no one to escort. __________________ Sub Skipper's Bag of Tricks, Slightly Subnuclear Mk 14 & Cutie, Slightly Subnuclear Deck Gun, EZPlot 2.0, TMOPlot, TMOKeys, SH4CMS

08-02-11, 09:48 AM	#15
WernherVonTrapp Admiral Join Date: Jul 2009 Location: Now, alot farther from NYC. Posts: 2,228 Downloads: 105 Uploads: 0	Welcome abroad zed055. Now I have a question. I've noticed while traversing the (I think) Yellow Sea that there are a lot of deep and rather thin slit trenches found in the shallows. Some are very deep and barely wider than my boat. Would hiding in the depths of one of these trenches have any effect whatsoever on the enemy's active sonar? __________________ "The journey of a thousand miles begins with a single step." -Miyamoto Musashi ------------------------------------------------------- "What is truth?" -Pontius Pilate

07-27-11, 10:23 AM	#2
Armistead Rear Admiral Join Date: Dec 2008 Location: on the Dan Posts: 10,880 Downloads: 364 Uploads: 0	Not in the game and unable to mod such. In fact, sitting on the bottom will eventually cause damage, it's like running into land.

07-27-11, 01:15 PM	#4
Ducimus Rear Admiral Join Date: May 2005 Posts: 12,987 Downloads: 67 Uploads: 2	If you drift onto the bottom you wont take any damage. By drifting i mean lowering your depth, without forward propulsion. All stop, zero speed, dive planes set to go deeper then the bottom really is. But no.. bottoming the boat will NOT help you. The only time laying doggo on the bottom is helpful, is if your about to enter a shallow water area, and your just waiting for night time to do it.

07-27-11, 01:48 PM	#5
Armistead Rear Admiral Join Date: Dec 2008 Location: on the Dan Posts: 10,880 Downloads: 364 Uploads: 0	Duci explained better, if I sit at the bottom actually touching land so that it rubs, even at 0, given enough time you can get minor damage, but never more than a few percent, you drag bottom with any speed damage will increase. Some use a minor glitch, if you set 0 speed, planes to go deeper than the bottoms actual depth, you won't take any damage at all. Still, you get no sonar effect hiding from sitting on the bottom in the game. Course in a crash out of control dive due to damage, I would rather hit bottom than head for the deep.

07-27-11, 05:15 PM	#6
Daniel Prates Grey Wolf Join Date: Apr 2011 Location: Curitiba, Brazil Posts: 938 Downloads: 65 Uploads: 0	It is my guess that active sonar will simply hit you and bounce back, regardless of you being in the bottom or not. Shouldn't make any difference towards detection.

07-28-11, 11:55 AM	#7
Ducimus Rear Admiral Join Date: May 2005 Posts: 12,987 Downloads: 67 Uploads: 2	Active sonar in SH3, 4 and 5, is much like a flashlight beam. It's always on, in a fixed width, and angle. If it see's you are not depends on how much of your subs surface area is exposed to the flashlight beam, and for how long its exposed.

08-02-11, 09:06 AM	#14
Armistead Rear Admiral Join Date: Dec 2008 Location: on the Dan Posts: 10,880 Downloads: 364 Uploads: 0	The main thing is once you lose contact with a DD, don't do something stupid until you've got some range on them. Very important with cams off. You may finally escape the circle, but they could still be hunting where they last had contact with you, if you increase speed, come up above the thermal, cut off silent running, one could hear and the whole herd could come back. It's also common for them to leave a sleeper behind stopped, so you get no sonar contact. Make sure you clear the baffles several times. I've set most of mine to elite status and they hunt you like dogs, sometimes the only thing I can do is wait for them to run out of charges.