(WIP) Ship's Acceleration Physics

[JREX53]

Originally Posted by NEON DEON

Maybe after this mod is complete we could have Fleet boat drag racing.

Ok T3 does the quarter mile in 6.7

Seconds!

no

Minutes.

Neon Deon,

I just reran my test mission for the T3 Tanker and I still come up with the acceleration from 1 kt to 18 kts, that I mentioned, at about 14 min and 10 sec.

[NEON DEON]

Here is a bit on the Missouri stopping.


"A full crash back is almost a non-event. That's where all four screws are reversed from full ahead to full astern. It takes a little over a mile for the ship to come to a stop before going in reverse, but there is no feeling of inertia throwing you forward - unless you turn the rudders inboard toward each other to close off the passage of water between the twin keels. That is called a "Barn Door Stop" and only the Wisconsin has ever tested it. A former XO of Whisky said that when they threw a piece of wood over the side from the bow at the onset of that maneuver, the ship came to a stop with that wood no further aft than turret III. That's stopping a 57,000 ton ship traveling at 33 knots in about 600 feet, which means that anything that is not tied down winds up on deck or against a forward bulkhead."



As Huel Howser would say"

"ISN'T THAT AMAZING!"


http://www.navweaps.com/index_tech/tech-054.htm

[vanjast]

Not to mention the loose rudders - Pretty amazing stuff.

I notice that happens with Websters mod that I'm using (maybe it's hard-coded), counteracted by this.

As you know I set up the TDC with false info. I fire one torpedo on the intended target. When this torp is gone I turn slightly towards the ship, anticipating the 'barn door stop'.
Sure enough the ship slams on the brakes, and the first torp misses. But the ship has left itself in a vulnerable position and I slam the the other 3 torps straight at it... and it now cannot accelerate away fast enough... Boom, (dud), Boom.

[NEON DEON]

Originally Posted by JREX53

Neon Deon,

I just reran my test mission for the T3 Tanker and I still come up with the acceleration from 1 kt to 18 kts, that I mentioned, at about 14 min and 10 sec.

JREX53

I am sorry I meant that to be a joke but did not qualify it as such. Not to mention it was a very bad one too. So please disregard the statement.

a few posts later i replied here:

Quote:
Originally Posted by JREX53
Webster,

That is what I am getting at. You have changed the drag coefficients unnecessarily.
The advice I was given by Sam (swdw), who started the initial physics work for SH4, gave me was to adjust the engine HP until you get into the ballpark, then adjust the engine rpm to get what you want, otherwise if you just change the drag coefficients you are asking for the ship to do weird things ingame.

WEBSTER:
the drag coeficients were used from PT's advice and i threw those values i used away and settled on new values.

i worry lowering rpm too much will cause ships that slow for evasive zig zag manuvers to get stuck doing 5 kts trying to regain speed. do you have a suggested number to start at?

and your reply:

Webster,

I haven't gotten that totally figured out yet. I have been using the same drag coefficients for all ships so far. I have been using the same values for the L/R drag and another value for the U/D drag (both surfaced and submerged).

I too also looked at PT's values and decided not to use them. I am also using a different value for the center of gravity then what he used.

I also noticed that you are using values in both surfaced & submerged drafts (draughts). Is there a reason for this? Not trying to be critical, just curious.

Keep up the good work on this, like Rockin' Robin said a while ago, the more people working on ships physics the better.

so you already said that you understood i had already come to the same conclusion of not using PT's values on my own so how can you now claim you told me to do that?

i was openly talking in posts about things that i was testing and often changing day to day in an effort that all of us could learn and maybe someone would come up with the best version of a mod, so should every person who ever made a valid comment on the subject get credited?. had you actually really given me any value then i would certainly credit you for doing so.

if anyone wants to read the whole thread to decide what really went on here it is: http://www.subsim.com/radioroom/showthread.php?t=149001

Originally Posted by JREX53

As a suggestion, I would not use just the drag coefficients to cause the speed changes. You lead yourself open for weird things to happen in game. "

Which would mean, to me, that I gave you the idea to not use drag coefficients to control your ships, but yet you have not mentioned the fact, in your readme, that I had an influence on how you did your mod.

Frankly I don't really care if you did or not, but it would have been nice.

thats because drag coefficients ARE what controls ship stopping speeds and inertia.

if any info you gave me was used then i would have mentioned it but i was only hearing things i had already figured out.

mainly i was exclusively discussing settings to control ship stopping but you seemed to only be concerned with what you were told by others about horsepower settings


plus if credit was needed to be given it would rightly go to those who passed the info to you as well


i spent endless hours of testing and retesting all those values to discover for myself what they did and the effects they have.

i would credit anyone who contributed to it but i cant be expected to credit every opinion in every post about things being discussed in general terms.

EDIT:
if anyone wants to read the whole thread to decide what really went on here it is: http://www.subsim.com/radioroom/showthread.php?t=149001

[JREX53]

Originally Posted by NEON DEON

JREX53

I am sorry I meant that to be a joke but did not qualify it as such. Not to mention it was a very bad one too. So please disregard the statement.

Oh ok!!

No harm done. But please left me know if you do find something weird happening.

[JREX53]

New Version of the Mod is up on SUBSIM and FileFront.

This version has the Light Cruisers completed. There are 2 separate downloads on the servers. One for the People who only play Stock or RFB without RSRDC, and the second one is for the people who play Stock or RFB with RSRDC.

Please enjoy the Mod

Links can be found in the First Post of this thread.

[JREX53]

I just found out I have to reupload the mods, I improperly zipped the mod.

I forgot to put the 2 folders into the "Data" Folder.

Sorry for the mix up, will have them uploaded tonight.

[Rockin Robbins]

I look forward to testing it tonight.

It seems like you and Webster are being way too testy with each other. You don't need to be duplicating each other's work, you need to be paying attention to how YOU are doing things and not copying each other's methods.

I doubt that Webster thought about the implications about what he said about you not testing his mod. Why would you even LOOK at his mod? As soon as you do you can be accused of copying. And you are encouraged to do things the easy way instead of first-hand research. Webster does not know that your mod has been in research for over twice as long as his. He only knows he released first and is assuming you are trying to horn in on "his territory" as a johnny-come-lately.

Players benefit when two truly independent mods are produced to address the same issue. Two heads aren't twice as good as one, they are about four times better. Just like the runner who looks back at his pursuer, breaks stride and loses the lead, it's best to look at the track ahead and run your own race. Later you can compare notes and mods, perhaps combining different methods to achieve a better mod than either of you can produce alone. Maybe there will always be two mods. Is that such a tragedy?

So far I notice that your mod has slower acceleration than Websters. Your mod has better station-keeping in convoys. I have noted one collision of convoy ships in your mod and none with his yet. Both mods are a thousand times better than stock and either mod alone would be perfectly acceptable.

[JREX53]

I have the corrected files uploaded to FileFront and one uploaded on SUBSIM. I got an error message when I tried to upload the second one to SUBSIM and am waiting a reply before I can get it uploaded.

[JREX53]

UPDATE to "SAP v0.3 Stock-RFB+RSRDC" Mod.

There was a error in the Stock/RFB/RSRDC version of my mod. The error will cause a CTD when attempting to view the Sub Chaser and Momi Patrol Boat in the Recognition Manual. The error was found by 399nkov, during testing, and the fix was found by Lurker.

The Patch can be found at the following links:
SUBSIM: http://www.subsim.com/radioroom/down...o=file&id=1146

and FileFront: http://files.filefront.com/SAP+v03+S.../fileinfo.html

A Special Thank you to 399nkov and Lurker for finding and fixing my error.

[JREX53]

Newest Update for the mod is now available. See 1st post for more information.

[JREX53]

Newest Update for the mod is now available. See 1st post for links.

[Rockin Robbins]

Excellent! I know how much work you've put into this. It's great to see the open modding process work so well, as we got to see this move from an idea into a sorta-working mod, the feedback came in, the mod evolved and now we're ready for the next step. This is going to be GOOD!

Thanks for what you do.