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Redphoenix

[Tutorial] Creating Custom Engine, Gearbox and Suspension [Vehicle config]

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Several people have asked me until now how I edit all the vehicle configs, how I create engine and gearbox files and how to setup the suspension.

This tutorial therefore will be divided into three parts where I am going to show you, how I do this magic. I will provide dummy files you can use, I will also provide the necessary programs and editor as well as excel sheets.

But there are some things you have to get yourself:

First of all: Basic mechanic understanding. How does an engine work, how does a gearbox work, how does suspension work? How does an engine generate power and torque when aspirated with a turbocharger? How when aspirated normally? What happens if you will soften the suspension on the back axle? What exactly does an anti-rollbar? eca.... All this is needed to create a good working vehicle config. I don't want to say here that I am a master in mechanic, I am still learning all of this more or less on the fly.

For the purpose of this tutorial I am going to edit the config file of the civilian Transporter.

Files:

https://dl.dropboxusercontent.com/u/84370332/Tutorial/Tutorial_files_engine.rar (checked with MS Essentials)

Contents:

Physicseditor.exe - http://www.nogripracing.com/forum/showpost.php?p=377688&postcount=5

Toms Engine Shop - http://www.nogripracing.com/details.php?filenr=10153

engine_calculation - Excel sheet to convert engine diagram into code. Versions for Office 2003 and Office 2007

pictures from this tutorial

this tutorial as a *.pdf - Removed until a full version is available.

This thread is full of helping ideas and hints:

http://forums.bistudio.com/showthread.php?149027-Primer-for-new-vehicle-simulation

BIWiki page:

http://community.bistudio.com/wiki/Arma_3_Cars_Config_Guidelines#Engine_parameters

You will need Notepad++ with the SQF-plugin, found on armaholic.

Part I

Engine

Before start creating the engine files, we have do some research on the Internet. What you need is a diagram of the torque and hp output.

The real "brother" of Arma's transporter is the Iveco Daily 4x4. With a bit of google's magic, I could locate an engine diagram for the top-model engine, which is a 3.0l twin-turbocharged diesel with 174hp and 400 Nm torque. The picture I found is quite small, but it is fine as long as you can read the numbers and can see the graphs. Take a look at them and write down where the highest output of hp and Nm are and what is the red-lined RPM is. For my Iveco the values are:

130kw = 174hp from 3300-3600rpm

400Nm from 1250-3000rpm

redline= 4100rpm

Now that we have this diagram, we can create our custom engine file.

Open now the program "physicseditor.exe". This is the most basic tool to create an engine file. It is fairly good usable for Arma3, even though it was created for rFactor and Race07.

Click "Edit" and then "Generate new engine data".

clipboard0172ut2.jpg

clipboard02fwubo.jpg

Take a look at your notes you just made and enter the values into the box which has opened. Don't mind that in this program the max RPM you can enter is 6000. We will manually edit this later. Where asked "RPM Steps", just enter 1000. We don't need steps smaller than that. You will see later why. If you entered all values, hit OK.

The program now created a generic engine file and it might be looking like this.

clipboard03bjue4.jpg

Don't mind the negative compression since this value is not necessary for Arma. If this value has a high negative number, just drag-and-drop it a bit higher (closer to 0). Editing this graph won't affect the data we need.

clipboard04rru8a.jpg

Now, open the engine diagram again and take a closer look on the curves. Now you need basic engine understanding: Because this engine is a turbocharged diesel, the maximum torque is generated at very low rpm. To edit your engine file now, drag-and-drop the yellow torque-curve until it looks the same as the real one.

clipboard0586uvc.jpg

Don't mind the red power-curve. You cannot edit this due to the torque-rpm-power relation. (For more about this, read: http://en.wikipedia.org/wiki/Torque#Relationship_between_torque.2C_power.2C_and_energy - You will need this knowledge later as well)

Now go to the Edit tab again and hit "Edit Engine/Tire Parameters". A biiiiiiig window will open now, where 99% of those numbers are irrelevant. Important is only the second line where it says "Rev Limit Range".

clipboard06zluxm.jpg

Enter in the first field your maximum RPM, then in the second enter 0, then 1. Hit OK.

clipboard07gau9p.jpg

Save this file now as [nameofyourvehicle].ini and open it with Notepadd++ or any other texteditor. Also, open now the excel sheet "engine_calculation.xlsx" which I provided. Please don't mind the "Imperial Values" which is written there. It's wrong and already corrected.

What is the excel sheet about?

It takes the values of your engine file you just created and rearranges the numbers for the config. If you take a look at this, it should be pretty clear. Enter now your maximum RPM, torque and power.

clipboard08jjum6.jpg

clipboard09lguov.jpg

The sheet will automatically calculate maxOmega, peakTorque and enginePower.

While peakTorque (in Nm) and enginePower (in kW) should be clear, maxOmega is a bit more difficult to understand.

Omega is the angular velocity, and maxOmega therefore the maximum velocity the crankshaft of the engine can reach. This value is what defines the the maxium RPM. When I first started editing configs I saw the parameter "redRpm" and was thinking that this value defines how far the engine can rev. But that's a false friend, because maxOmega "really" defines that. (Thanks here to da12thmonkey for explaining me all of this), Check the wiki page linked above for more informations.

Okay, back to the sheet. On the left-hand side there is a column named "RPM Steps". This column is rather important, because it divides your whole RPM curve into 8 steps, whereas the first step always 0 RPM is. You may ask yourself now: "Why 8 steps?!". Well, I cannot explain this to you, because this was defined by Bohemia.

Switch now back to your [nameofyourvehicle].ini. The very first lines are important, to be exactly, the ones starting with "RPMTorque". Those lines are defining the curves of torque and hp. But now, we have to trim down those lines so only 8 will be left. I hope you see now where we are going.

clipboard109nuum.jpg

Edited by RedPhoenix
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Copy the 7 lines of data from your "RPM Steps" column into the [nameofyourvehicle].ini. You may have to delete a line or two, but nevermind, we will readjust the curve later.

clipboard11gnuhk.jpg

Save this file now as [nameofyourvehicle].eng . An *.eng file is nothing more than a specialized *.txt file used in racing sims. You can close Notepad++ now, but keep the excel sheet open as you will need it in a second. Open now "Toms Engine Shop-1-2.exe" and open the newly saved *.eng file.

And there you got it, more or less. This is your engine graph. If you have strange values or your curve differs from the original, you can edit them again with this editor. Doing this should be pretty straight forward.

clipboard12x5u9z.jpg

CAUTION: The value used in this editor for torque it ft lb. Use this converter to calculate the needed ft lb from your Nm values: http:// www.convertunits.com/from/ft+lb/to/N+m

Avoid as well very small numbers, like "2hp". If you won't, the car will go off very very slow, but will suddenly make a big jump forwards.

And here you can see my final diagram.

clipboard13klua4.jpg

Click on "Update Engine File" to save.

Before we transfer the values, check that your max HP is correct. For doing so, click on "File" and then "Select Max HP". When the value is different from the one you are aiming for, simply enter the wanted one and hit OK.

We have now 8 values and a finished graph, so we can start transferring the values from the engine shop into the engine_calculation sheet. Use only full numbers, avoid things like "256.7". Use 257 instead.

clipboard14nfugo.jpg

I added a diagram which reads the excel values, to check if you entered the right values at the right places.

The diagram should be the same as in the Engine Shop.

clipboard15rxujv.jpg

If it is similiar, you got it right. You entered the values into the right slots.

Now take a look at the right side of the sheet: you are seeing a lot of code. As you see, I already prepared everything for a simple paste. The values in the parentheses aren't arbitrary, they are the percentages/100 of the engine value. It is always

{Percentage x of the max RPM/100 ; Percentage y of the max torque/100 };

And there you got your 8 points which the game engine uses to create the engine.

clipboard16wnudp.jpg

Now open your config and locate the values in there.

clipboard17wquhr.jpg

All left to do now, is simply copy the code from the excel sheet into the config. At this point I tend to delete the old values and to rearrange the config to keep engine code together.

Make sure the value for "redRpm" is your desired value.

clipboard18yyulb.jpg

Now lets got over to the clutch and power distribution.

It's fairly simple to understand. At first make sure your "clutchStrength =" is high enough. If you don't know how good is enough, try this:

Start with "clutchStrength = 5". If the clutch slip (you will hear and feel that), try "clutchStrength = 6". If it's slipping again, try "clutchStrength = 7" and so on.

Generally, you will need around 5-8 "value" every 100Nm. If you car has 400 Nm, try values ranging from 20 to 32 until you found the right spot.

Next step is only optional:

The parameter "frontRearSplit" defines how much torque goes to the front and back axle. The Value 0.5 is 50/50 distribution, 0.0 00/100 and 1.0 100/00. in Real world, roadcars with AWD have around 70/30, so you want to enter 0.7. the Iveco has 32/68, so I enter 0.32.

You can leave all other parameters untouched for now.

And now, pbo this config and test it. If you test it with an Arma car, be prepared that it will drive like crap, because we haven't configured the gearbox yet.

But that's part of the next post.

I will edit the second part into this topic as soon as I can. I am still on the way to create dummy files.

Edit:

Oh, and sorry for my rusty english..... It was a very long day.......

Edited by RedPhoenix
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(I hope this works and that the Forum doesn't edit this post into the one before...)

https://dl.dropboxusercontent.com/u/84370332/Tutorial/Tutorial_files_gearbox.rar (checked with MS Essentials)

Contents:

Gear Ratio Calculator - http://www.nogripracing.com/details.php?filenr=36099

pictures from this tutorial

this tutorial as a *.pdf

Okay, let's work now on the gearbox. Most of the code lines we need are inside the "class complexGearbox {}".

clipboard01csx9t.jpg

For more infos, check out BIWiki here: http://community.bistudio.com/wiki/Arma_3_Cars_Config_Guidelines#Complex_gearbox

Now open the "Gear Ratio Calculator" I provided. This program allows you to edit a gearbox within a very sensitive way.

clipboard02xmxl2.jpg

All you need to do is press the button on the left upper corner to select the dummy_hdc.hdc file which comes with the ressource files. The programm will ask you now to open the *.eng file. Normally now you would be able to open the *.eng file we used for the engine, but due to a bug this is not working. We simply hit abort, then OK. Now the programm asks us to open a gearbox file. But because we don't need that, click again abort, and OK. Because we havent selected a engine file, we have to enter max RPM manually on the left side. Next to it there is the field for tire radius. Go now back to your config and search for "wheelCircumference".

It should be pretty clear what this value means and due to the big number I guess it's in meters. To get the tire radius, we simply divide this number through 2 π. To get in into milimeters, just multiply it with 1000 For me it would be 2.805/2 π = 0,446 *1000 = 446mm. We enter the result into the field.

Now we have to setup the bevel gear, which is the top right box.

Because we only need one bevel gear ratio, we enter only one ratio value there. For a truck or a big offroad I would use a number around 5-6, for a normal car 4.

I will use BIS value, which 4,136. This is basically the last transmission ratio after the gearbox. Check the wiki for more info: http://en.wikipedia.org/wiki/Bevel_gear

The codeline for the bevel gear is: TransmissionRatios[] = {"High",4.136};

Now we go to the window below. This is basically where we create the gearbox. I will enter BIs values to show you how to start. The first Ratio should always be the reverse gear, which should be a short gear. Don't use negative ratios here because the program won't recognize them. For the rest then use values which are getting smaller and smaller.

clipboard03wkyv6.jpg

All left to do now, is assign those values to the associated gears. We do this by simply selecting them on the left side. The program now draws a very informative diagram to show you the gears.

clipboard04lpxt1.jpg

Now, if you are making a brand new gearbox from scratch, here are some tips:

- Make the 1st and 2nd gear rather short.

- Keep your last to gears nearly the same in the way of speed they are covering. I made the experience that speed coverage from 20-30kph are very good.

- Check the max speed of your vehicle don't go too far over that if you don't want to have a horrific time setting up the gearbox, because the power you gave the car won't be enough to handle with the gearbox

Check now the top speed of your vehicle you are making. The top speed of the Daily 4x4 is 80 mph, which is around 130 kph.

We'll go now back into the calculator and play around with the ratio until the max speed of the last gear is around 10 kph higher than the real max speed (We don't want to be driving around on the rev limiter all the time).

The ratio I think fits best is 1,19. Now we have to setup the rest of the gears as well. All in all, this is just playing around with numbers. Try avoiding gaps which are too big as well as too small.

This is how I ended up with. Notice that I have the same ration for reverse and 1st gear.

clipboard05smxx0.jpg

All what is left to do is copy the values into the config. This is fairly simple, because we just need to replace the old values with the new ones.

clipboard06wxyzj.jpg

Don't forget the minus before of the reverse gear. Now pbo the config and test it. The best area for testing is around Zaros. Speed test are good at the airport. Uphill performance around Abdera.

Don't just drive around for a minute. You need to do a longer driving to get a feel.

If you are happy with what you see and feel, you are done.

If not, change the numbers a bit around and test again. If you want to test only a certain gear, you can do something as this:

GearboxRatios[] = {"R1",-5.3,"N",0,"D1",5.3,"D2",3.2};

The vehicle will only go into second. This is quite good to get a feeling when the gearbox changes a gear. If you want to increase your overall ratio, change the ratio of the bevel gear.

If the gearbox switches always back and forth, shorten the bevel gear a bit, or shorten the longer gear rations (Mostly the last and second-to-last one). If the gearbox runs out to fast but you think you gear rations are fine, make the bevel gear a bit longer.

You may have noticed some other codelines. For most of them BI Wiki has explanations, except the following:

gearUpMaxCoef = 0.9;

gearUpMinCoef = 0.7;

gearDownMaxCoef = 0.75;

gearDownMinCoef = 0.7;

What I thought:

"gearUpMaxCoef defines that the gearbox will change one gear up at a maximum RPM of 90% redline-RPM. gearUpMinCoef defines that the gearbox will change one gear up when a minimum minimun of RPM of 70% redline-RPM is reached. Viceversa explanation for gearDownMax/MinCoef.

But I made the expierience that those values won't change very much of the gearbox situation."

http://forums.bistudio.com/showthread.php?149027-Primer-for-new-vehicle-simulation&p=2493741&viewfull=1#post2493741

EDIT:

Okay, I browsed a bit around the VBS Manual, and this is what it means:

gearUpMaxCoef = 0.95; //coef for changing up in automatic or semi-automatic gearboxes with full throttle (0.95 by default before redRPM on actual gear)

gearDownMaxCoef = 0.85; //coef for changing down in automatic or semi-automatic gearboxes with full throttle (0.85 by default before redRPM on lower gear)

gearUpMinCoef = 0.95; //coef for changing up in automatic or semi-automatic gearboxes with no throttle (0.65 by default before redRPM on actual gear)

gearDownMinCoef = 0.85; //coef for changing down in automatic or semi-automatic gearboxes with no throttle (0.55 by default before redRPM on lower gear)

http://manuals.bisimulations.com/vbs2/2-00/devref/#Adding_Models/How_to/AMHT_Physx.htm

I don't think you really need them, but it's good to have them even if they don't really do anything (yet?).

But important are:

switchTime = 0.41;

latency = 2.0;

Make sure you have them, because they define how the gearbox switches gears.

"switchTime: The switch time describes how long it takes (in seconds) for a gear change to be completed. RPM interpolate to optimal value for the new gear at current speed during the changing of gears. The time should be rather low, around 0.3 s, to keep the momentum of the car.

latency is the minimum time (in seconds) that must pass between each gear change that is initiated by the autobox. This should be set to value higher than switchTime. Setting this time too low makes some issues with changing gears - the car slows down a lot"

http://community.bistudio.com/wiki/Arma_3_Cars_Config_Guidelines#Gearbox_parameters

In total, getting everything right is only testing at this point. Change a value, test it, if you are not happy, change it again, test even more. This can be nerveracking sometimes to get it right, but it's worth it.

Next part is about the suspension. Be prepared for a lot trail and error, but for some very cool results.

Edited by RedPhoenix
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Now we are going to edit or create the suspension. But before we go into our config, we should make us a plan or a scheme, how we want our vehicle to ride.

https://dl.dropboxusercontent.com/u/84370332/Tutorial/tutorial_files_suspension.rar

Contents:

-Pictures

-"suspension_calculator" - Excel sheet for calculating spring values. Versions for Office 2003 and Office 2007

If you have a sports-car, it should stick to the tarmac very good which means relatively hard suspension and hard Anti rollbars (ARBs). If you have a normal car, you want soft suspension, but hard ARBs as well. If you have a truck, you want to have both fairly soft.

Let's recap: What does the suspension? Well its main function is cushioning unevenness of the road. Therefore it uses two main parts: a spring and a damper.

The spring damps all the bumps while the damper prohibits the spring to exert the force gained while compressed to be released in its length axle. More or less the damper holds the spring "in position" and controls its force release. Without dampers a car will eventually start oscillating up and down which will cause instability and a crash.

A car or truck with heavy load will use harder suspension to overcome the weight of its freight. Same goes for a sports car where the forces applied to the vehicle are much more extreme than compared to a road car. But both are having a very hard damper to control the moment of inertia of the overall weight.

Now remember what ARBs are doing: If you go, for example into a right turn, the right suspension will be lifted up while the left suspension will be compressed. Therefore the bodywork will lean left.

car_leftz4ucn.jpg

If you go fast enough into a corner, the car will eventually roll on its side (notice: that's the main problem of the Arma3 civilian truck). To prevent the car lean the ARBs are dividing the overall force applied to the suspension between both sides.

car_left_arbkouyl.jpg

(Note that both yellow suspension blocks are smaller due to both being compressed when driving around a turn with ARBs)

This prevents the car to lean too much.

If you want to read something which goes a bit more into detail, this page explains it pretty good:

http://www.stealthtdi.com/SwayBars.html

So, let's get digging then. Open up your config, and at first we want to look for the ARB parameter (if you need them). I usually take them and switch them a bit lower, right before the "class wheels{};" The rest you need is in the wheels class. Take a look at some of those parameters. Most of them should be pretty clear just by reading them, but some of them are a bit tricky to get. To test each single one of them, paste a copy of the line directly below one and comment via // the original line out. This way you will not lose the original value if you test them. It will appear green then. Best way to get a feeling which parameters does what is to test arbitrary high and low numbers.

clipboard01r2ufk.jpg

One of them is "MOI". MOI means "Moment of Inertia". If you are not familiar with this term, check out the wiki page: http://en.wikipedia.org/wiki/Moment_of_inertia

I THINK this value means the Moment of Inertia of the spring. Lower values allow the spring to compress and decompress more easily than smaller values.

"dampingRate" is I THINK the factor to define how soft or hard the dampeners are. Bigger values mean softener dampers. Value 0 is no damping at all. Do not go over 1, if you do, the acceleration of your vehicle is affected (ITS MAGIC!!!). I prefer the value 0.5.

" maxCompression" is the maximal point of compression (or minimal point of decompression). value 0 here will allow the suspension to fully compress into the body. Notice that when value 1.0 applied, the tires will stick into the ground due to not allowing the suspension to compress. I think values around 0.1 to 0.2 are fully acceptable and realistic.

maxcompression_0k4s3b.jpg

Note that tire rear tire suspension is fully compressed at value 0.0. The tire would be ripped here by the mudcover.

maxcompression_1ahs34.jpg

Note that the front tire sticks into the ground at value 1.0.

Same goes for "mMaxDroop" which is the minimal point of compression (or maximal point of decompression). Keep this value rather low too. Around 0.2 should be fine.

Now it's getting technical. Open up the excel sheet.

clipboard02_smallplum2.jpg

Look up your vehicles mass in the internet and enter it into the appropriate field. Same for the number of wheels (pretty difficult, huh?).

The mass of the Iveco Daily 4x4 is 2490kg. The sheet will automatically calculate the values for sprungMass, springStrength and springDamperRate. What are those numbers?

spungMass - is simply the weight which is loaded on one tire. Keep this value the same, since weight will not change.

springStrength - is how hard the spring and therefore how hard/soft the suspension is.

springDamperRate - is the self-damping-effect of the spring.

Now, this sheet gave us only the basic values which are generated through BIs formulas. pbo the config and test them. Now remember what we have said at the very beginning about how a specific vehicle has to be. The Iveco has to be rather hard, but with the formula BI provided the suspension is very very soft. So from here on it's all about testing. Lower or rise your values to get the best setup. And only change one value at a time. In my case I will raise the strength of the spring to make the suspension harder. If you are confident with your suspension, you have to align the value for springDampingRate. Check the excel sheet to edit the value.

If you are happy with how the car reacts to bumps and unevenness, let's go to the ARBs. They are an important nowadays since the prevent a car rolling over.

Check the BI wiki for explanation: http://community.bistudio.com/wiki/Arma_3_Cars_Config_Guidelines#Anti-roll_bars

Now, to test it out, simply test again with extremely high or low numbers to identify what they are actually doing and to get a feeling for that.

BI Wiki says that you don't need to apply a higher value than 2 at "antiRollbarForceLimit" but I made the experience that you can and should. I set this limit to 5 for my Truck, and it's absolutely fine.

The other 2 values should be pretty good explained in the wiki.

When you found the best values, it's time to get to the tires. Go back into the "class wheels{}" and lookout for the parameter "frictionVsSlipGraph[] = {}". I had a hard time understanding this value, that's why I am going to quote here da12thmonkey and Blu3sman.

http://forums.bistudio.com/showthread.php?149027-Primer-for-new-vehicle-simulation&p=2494227&viewfull=1#post2494227

http://forums.bistudio.com/showthread.php?163352-Refined-Vehicles&p=2496764&viewfull=1#post2496764

This can get very tricky if you want to fiddle around with the values by yourself, but my advice is that you simply take the code out of the links above. They work best in all situations for all kind of normal vehicles. But if you want to get the best out of it, just test with some values until you got it.

Last but not least: Brakes.

I will make it quick and simply: Define more" maxBrakeTorque" to the front axle than to the back axle. This will make braking a lot better due to the weight transfer of the car. For "maxHandBrakeTorque" take a rather high value. BI recommands 2x maxBrakeTorque, but I would say make it 3 or 4 times as big.

______________________________________________________________

Well, that was all. I hope you learned something (and didn't die from my English) as we covered most of the parameters and I hope you guys now know how to setup some by yourself.

If you have any questions, feel free to ask here. I will steadily update this topic add/correct any information. If I think it is worth I will pack all together and create a good-looking PDF-file.

Be sure to check my thread about editing the A3 vanilla cars here: http://forums.bistudio.com/showthread.php?163352-Refined-Vehicles

Until then:

Happy Coding!

Edited by RedPhoenix
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Editing Boats

Boats and PhysX are a great combination, if the config is well made.

But doing so requires some work and tweaking. What you should have by now is:

- The model; ready in o2 with the real mass and it should be binarizeable

- A working config

- Some technical information about the ship you are making

Before you start, look up for some videos. What’s the ship behaving like? Has it a small turning circle? How fast does it go? Those informations are vital to give your ship a believable behavior.

Let’s start now:

Grab yourself a fitting config. Everyone from the vanilla Arma3 boat-class will work. To make your life easier, you should rearrange the lines to find certain values faster.

Normally it is looking like this when I am ready to work:

zwischenablage0102k2c.jpg

We should start by making the most important bit of the boat: the engine. I have to thank here now Hatchet_AS for letting me use his MkV SOC boat as a tutorial template!

The MkV uses two MTU 12V396 TE94 diesel engines. You can either google it now or use what you already have to make the engine’s power diagram. The MTU engines are producing 2 x 2285HP, according to the MTU data sheets 3400Nm torque each and have a rev limit at 2000rpm.

In total that is:

- 4570hp / 3408kw

- 3400Nm torque @ 500 to 1300rpm

- max RPM @ 2000rpm

That’s all you need. Make the engine file now, and if the program doesn’t support this big numbers, use half or a quarter of the values. You can multiply them later easily.

If you are ready and filled everything into the excel sheet, it should look something like this:

zwischenablage028hjpf.jpg

Those values are good and you can paste them into your config. The engine is done now.

Before we go over to the gearbox, there are some important bits you should do now:

Look for the line: “waterResistanceCoefâ€. This line tells the game how big the friction between your boat and the water is. I find that generally 0.002 is a good starting point. You can either edit now your “waterLinearDampingCoefY†and “waterLinearDampingCoefX†now, but I prefer tweaking that when the boat is running.

For an explanation, check this link to the VBS manual:

http://manuals.bisimulations.com/vbs2/2-00/devref/#Adding_Models/How_to/AMHT_Physx.htm

The gearbox class is quite tricky to handle. It may sound odd that boats have a gearbox, but without it the boat wouldn’t drive like it should. Trust me: When you are finished, you will not take notice off the gearbox.

Basically you can do here whatever you like. I prefer a “TransmissionRatios[]†close to 1. That prevents you from fiddling around too much. Only edit this later to maximize your speed which is why I have that on 1.18.

Enter now as many gears as you like. I prefer 4 to 5 for bigger boats, for smaller ones at least 2.

You can use the gearbox calculation sheet I provided, but it’s quite tricky because you have to guess the radius of your propeller (even if that sounds ridiculous).

The mix between the gearbox and the “waterResistanceCoef†will make the biggest difference in how your boat accelerates.

If you are content you can now switch over to editing your rudder parameters doing that is pretty straight forward:

rudderForceCoef = overall force of rudder

rudderForceCoefAtMaxSpeed = relative force when driving at maximum speed ; you want to keep this rather small.

If you have done this, the last step is to edit and tweak the overall behavior of your ship which is controlled by the following lines

waterLinearDampingCoefY

waterLinearDampingCoefX

waterAngularDampingCoef

Check the VBS manual for this to find good explanations.

Overall, boats are pretty easy to make but the results are very very good.

Edited by RedPhoenix
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very impressive guide and work there RedPhoenix!

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Thanks kju, I hope it will proof helpful for some modders here.

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Red, when I'm making sure that the correct max HP was set in Tom's Engine Shop, the max is 2000 that I can input. However, I have an engine that pumps out 2285 HP at a max RPM of 2000, it's a turbo diesel. How would this effect the data? Also are you positive that enginePower is in kW and not HP?

Edited by SpectreRSG

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Yes they are in kW.

You can easily use halfed or quartered values. So you could use in the engine generator 1/4th of your total power which would then be 1143 HP, and if you are later working with the sheet multiply with 4 to get the total HP you need.

Edit1:

I might dig myself into Java to write a program used to correctly displaying and calculating all of those values. It would be more or less a generator and editor for configs with an easy-to-understand GUI.

Edited by RedPhoenix

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Great stuff RedPhoenix, this is really good info on understanding the potential for the physX system. Have you had any ideas or found much in the way of parameters that might enable manual transmission? I've had a bit of a browse in VBS2 devrefs, to no avail. Or at least, nothing supported for A3. Anything on your end?

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No, manual transmission is currently not supported.

I really hope that BI will include this later.

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This .... is .... awesome....

Thank you dude, I will dig myself deeeeeep into that site.

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Is this the only way I can increase the speed of my vehicle? I've been playing with maxSpeed and nothing I do can get me past the 86 km/h barrier.

I wouldn't mind the speed limitation if I could get the thing to act like a beast, but it feels like a regular car that can't go very fast.

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Are you going for a mod vehicle? If yes - Does PhysX and simulation = carx work like it should?

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Is this the only way I can increase the speed of my vehicle? I've been playing with maxSpeed and nothing I do can get me past the 86 km/h barrier.

This is the current issue hindering my vehicle as well. Playing with the transmissionRatios[] param (specifically, lowering) Allows a substantial increase in the maximum speed, but still warrants unwanted behavior. BadHabitz, assuming you're working with an entirely new vehicle - have you tested your vehicle with other config settings, say, from an SUV or Hunter? Also, if you're changing the amount of gears or Redline RPM - Be sure to update the engine sound mathematics in Sounds{};

Really should just contact Nvidia about PhysX questions :rolleyes:

Edited by Ceds

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This is the current issue hindering my vehicle as well. Playing with the transmissionRatios[] param (specifically, lowering) Allows a substantial increase in the maximum speed, but still warrants unwanted behavior.
Real world values for gear ratios should work just fine. What's an unwanted behaviour?

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Make sure that PhysX is working 100% fine. w/o class complexGearbox will not work.

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I will update the post sometime next week with some more information about boat configs: What is important to know and what you have to keep in mind when writing your config.

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This is a great source of information and I commend you for your effort, thanks Red!

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This is a great source of information and I commend you for your effort, thanks Red!

I hope once more PhysX features are implemented we got the same vehicle simulation as in any racing sim :D

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physicseditor.exe crashes on start for me, is there an alternative tool that can be used that works? I'm on Windows 8.1 64 bit.

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the gear box program isnt plotting my gears when i try to assign the gears, it says error adding point to plot, i followed your post to the T, i believe, any pointers as to what i am doing wrong? I got the engine values fine, its just the gear box program that is holding me back now..

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you could use my excel file instead

http://www.multiupload.nl/UV4QR9IFAH

It does essentially the same, except you dont need to enter the number of teeth for all those gears (tedious!), and you can see the theoretical Drive diagramms (Torque-Travelspeed and Power-Travelspeed) for all gears

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