Physics discussion thread

Not really ?

 

Dear Reiza team, I have been a fan of AMS2 since release but only joined this forum today to ask this question: could it be that the weight of the car in the input sheets of the cars is in kilograms but that the Madness engine calculates with Newtons? I often have the feeling that the car does not weigh enough and does not push enough onto the road. I was wondering if maybe a factor 10 (kg to Newton conversion) is missing? For example, formula v12 feels light to me and so do the GT3s compared to other sims. Maybe it’s a stupid question or it has been addressed already, but I thought I give it a try anyway. Please keep up the good work!

 

Newton is unit of force, not a unit of mass. These are 2 different things

 

that’s exactly my point: if the Madness engine calculates with Newtons, then the input variables need to be in Newton as well. Frankly, I don’t know anything about the Madness engine and was only asking the question out of curiosity

 

The values shown in the UI are from my understanding completely decoupled from the values used in the physics. When new vehicles are in early development the values can often show up as 0, which is a value that cannot be divided by, so we would discover it very quickly if the values in the UI were used in the physics directly

This is likely due to two factors: Force feedback and camera settings.
Some of this is within your control to change, other aspects are up to Reiza to improve upon.

 

Typically a physics engine has far more complex calculations - it's not as simple as "using the wrong unit" as a fixture will have particular attributes such as density, weight, and friction levels that are used by the engine to determine how things work. So, your 'force' calculations will then be taking into account weight, density, friction, speed, air resistance, etc.

But, I agree with Roar - how heavy the car feels to you is a product of FFB and camera settings.

 

Lets continue this conversation here, its better.
First I'll say, AMS2 has a far more oversteery tendency than understeery one, thats true, and my biggest problem has always been the initial rotation on throttle that you get on some cars, but the idea that you can't overload the front tyres in the sim is simply untrue. Kinda of a dumb video here to show my point:

Obviously I'm exagerating my inputs here to prove a point, but even in 2nd and 3rd gear corners this mclaren is going straight on throttle, this also was recorded with 0 TC to make it even harder on the rear end and the car understeers in the situations I'd expect, through turns 3 and 4 I floor it while turning to see what happens and the rear moves a bit until the front gives up, turn 9 is the same story as turn 3 and then turn 11 on exit is the same story as turn 4, if I keep flooring it the car will go into the gravel. You can even see at T1 in the second lap while the car is rotating on the brakes into the corner I go on throttle and it inmediately starts going straight.
In sims it's all a matter of values, I personally believe the tyres sidewalls are a bit too soft in the GT cars and they tend to move on the tyre too much, which is what leads to this tyres having a bigger slip angle than expected, but I don't think you always end up managing oversteer in any corner, I'll depend on the car, track, conditions and setup.

 

I also completely disagree that it is "impossible" to understeer in AMS2. I've driven a whole bunch of different cars in the sim and every single one of them I have done my best to optimise front-end grip. Perfect example I have at the moment: McLaren MP4-12C Retro 3 F1 car. Understeers like crazy if you don't get the line right on corner entry. It also drifts beautifully - so if you lose the tail end, out of every car I've driven I can actually recover a slide 99% of the time. I'm not sure if that's due to recent changes but it's been a lot of fun

It's also very easy to "fix" the snap oversteer by simply reducing engine braking strength in the cars affected by it.