# Primer for new vehicle simulation

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This is epic! Thanks, I do understand certain things better now.

The same you said about the friction coeef = 1 appeared strange to me.

My own values are:

frictionVsSlipGraph[] = {{0,0}, {0.25,0.0}, {0.5,0.25}, {0.75,0.5}, {0.8,0.5}, {0.85,0.6}, {0.9,0.65}, {1,0.8}};

Which then, after reading what you wrote, makes more sence now why it works better then BI's standard value.

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Thinking about it, I'm not 100% on whether the constant "1" value is the friction, or the slip ratio.

Since the parameter is named frictionVsSlip it kind of implies that Friction Coefficient is the X-axis and Slip Ratio is the Y-axis - which would make a bit more sense since it would imply that the BIS vehicle's slip characteristics would be the same for all surface types, rather than different slip characteristics result in the same friction coefficient - which seems nonsensical.

However, the convention when graphing those values on real systems seems to be X=slip Y=friction coeff, so that it displays as a nice asymmetric bell curve

Would be nice if someone at BIS could explain which one was which.

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Thanks for all those infos.

Btw, you should add into your info that the equation you give has to be used with SI values. Therefore it is not

Power (in kW) = Torque (in Nm) * Angular Velocity (in rads/s).

It actually is

Power (in Watts) = Torque (in Nm) * Angular Velocity (in rads/s).

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Oh yea sorry, you're correct. It's because when I wrote the original post I had the enginePower ratings (which are rated in kW) stuck in in my mind and I forgot power needed scaling down for the raw equation.

For the sake of being consistent with the scaling of units BIS appear to be using in their configs though, perhaps

Power (in kW) = Torque (in Nm) * Angular Velocity (in rads/s) / 1000
would be better?

But to be honest, the equation was really just there to demonstrate where Omega fits in the Power/Torque relationship, to justify why I though maxOmega is angular velocity: You can't really derive the enginePower, peakTorque and maxOmega values from one another, so the above equation has little use in writing configs (rated power isn't normally quoted at max rpm/omega or max torque - it's a rather arbitrary value applied by the manufacturer).

You kind of need to look at the manufacturers specs for real engines/vehicles, which normally quote the power rating (and the torque at which that power is rated), the maximum torque and max RPM or the RPM at which the vehicle redlines (from which you can calculate maxOmega).

Edited by da12thMonkey

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That's what I am doing.

For my refined offroad I used engine parameters based on a 2.0l TDI VW Amarok Engine. (180hp @ 400 Nm)

I calculated maxOmega based on your equation and the result is now even better then before.

I am going to refine the Hatchback now, where I am going to use engine parameters from the Honda Civic petrol version (1.8 i-VTEC - 142hp @ 174Nm).

Thanks for your help so far, I am very pleased how the engines are behaving with their new setup.

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MOI in class Wheels [] is nothing more as the force needed to make the wheel rotate. Smaller numbers mean lesser force needed, bigger numbers more force needed.

Example: to make a car spinning it's wheels, give the rear wheels the following code:

MOI = 0.5

A good starting point for smaller vehicles are:

MOI = 8

for Bigger

MOI = 20

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does anyone know what would cause my wheels to do this? http://imageshack.us/a/img27/5838/1074102013031000006.png

Your Suspension is screwed up, you have to change it in you model.cfg

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So the animations for the wheels of the truck are screwed up and they don't actually turn, I've been looking around like crazy in the config and I can't find out what it is I need to fix. If anyone could help me, it would mean the world to me.

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In response to wheels not touching the ground, if I remember correctly the solution is to move the wheel_x_x_bound points to the INSIDE of the tire. The actual tire height is determined by the distance between the wheel_x_x_bound point and, I think, the posun wheel_x_x points. Just scale the _bound points inward until it sits correctly. I'm sorry, I actually did put together a fully working example model that had everything that an A3 vehicle could have, including visually damageable wheels, but I didn't quite finish it or post it. I stopped because I thought the A3 sample model would be sufficient.

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question about water impact ... all our vehicle dont have any impact when coming to the water. i found on config viewer all water effect and then rewrite it in my config , but look like not working adding "LWatereffect" and "RWatereffect" in memories lod and nothing working again. if somebody can help me to have a realistic water impact on our vehicle creation

very good

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Maybe a stupid question, but after browsing through the guidelines on car handling, I could not find where to place my override model.cfg in my mission. I found https://community.bistudio.com/wiki/Model_Config, but that only shows how the default is implemented

HOw do i use the override model.cfg for the offroad settings described in this thread?

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Do you mean the model.cfg, or the config.cpp ? I'm not shure if you can replace a model.cfg, it has to be in the same folder as the model

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I only want to adjust the handling, so i think i only need the config.cpp. Can i have custom handling for the offroad per mission?

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Sorry it doesn't work like that. You have to pack it into an addon .pbo and it can only override the existing offroad or make a new one, it cant be loaded in just one mission. A3 basically compiles all the config.cpp stuff at startup and it can't be changed while the game is running.

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Ok, understanding it better now, thanks

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i don't know if its the right place but is there a more explanation in detail how the fuelConsumptionRate vs. fuelcapacity works? I tried for the HEMTT following ( only for testing to understand the consumptionrate )

```fuelCapacity = 285;
fuelConsumptionRate = 15000;
```

and it seems the fuel goes not so down like the original ones....but its funny, if im funny and using a fuel capacity from 22 litre and a consumptionrate of 1500, my tempest got a max distance of 46,15 km

( Im trying to get a higher consumption for altis life, because within my 6 hours serverperiode and a "need to pay to refuel -> fuel stations" script its better to have a higher consumption )

but for a truck a capacity of 22 is redicolous, it should show more "realistic" capacity

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I'm trying as well to understand how this system works, but hat little to no succes.

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I believe what I did with my CH-47F addon was: max Distance divided by fuel capacity = Consumption rate.

AI checked the outcome by "flying" the outbound of the Altis map which a full round is 120KM x 6 = 720km

+ from base to edge and back = +- 25ish km

when I came back home the helicopter made it back to base with only very little fuel left (reserve fuel).

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Hello guys, When I see this detailed topic I want to ask my hard question where may be I will have an answer. I'm doing a Chinese army trucks mod, in fact a Zamak truck retexture with green color and PLA logo... I've made my transport truck and my transport covered truck with no problem. Now I'm on the medical version of the zamak. Here is my problem: how can I delete the medical logos wich appear on the model, I tried to find in the config.cpp file how deactivate it but i didn't find it. May be you can help me.

this is cool

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Hi all, i have a question and i hope u guys can help me :)

I want to create a small replacement pbo which overwrites the: maxBrakeTorque

So that the vehicle brakes dosent work even if ai or player is braking.

I rly need it for a mission and hope of a help.

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Whats the problem then? Set brake torque to 0 has to be done for all wheels on all vehicles then. Pretty bad idea. Force speed via script alternatively

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Hi, Could anyone explain in a bit more detail this part of the config as i'm having a bit of trouble understanding it?

```	driverAction = "driver_offroad01";
cargoAction[] = {"passenger_low01", "passenger_flatground_leanleft", "passenger_flatground_leanright", "passenger_flatground_crosslegs", "passenger_flatground_leanleft"};
getInAction = "GetInLow";
getOutAction = "GetOutLow";
cargoGetInAction[] = {"GetInLow"};
cargoGetOutAction[] = {"GetOutLow"};
```

More specifically the following points:

1) Is "driverAction" requiring a memory point location (in this case "driver_offroad01") or is this not a memory point?

2) For "getInAction" is this a memory point or an animation I need to configure in the model.cfg?

3) Is there anything else I need to add in order to be able to get in or out of my vehicle beside using these commands and adding some memory points?

I'm inheriting from LandVehicle and StaticWeapon.

I think it may be worth putting the details on the BIKI as its a bit thin on information regarding this.

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What should I do when it comes into adding UAVs and UGVs?