Strange spin when rejoining from grass/off-road

Many times, when returning track from grass, the feedback becomes very strange, and many situations seem completely contradictory. For example, in the video clip I posted, it seems that the car got kicked in the rear when entering the track, and there was a sudden acceleration that made the car spin(no throttle or brake input during the entire process).
Is this a script SPIN?
Many players in my group have encountered this kind of problem, which is very counterintuitive. We hope to find the cause and fix this problem asap.

video link ↑

 

It looks pretty natural to me, there is suddenly change of grip while turning and this is a bit sideways, so I don't know what else would you expect from that

 

BTW, I countersteered the moment I feel the car is going to spin. However, on the grass, it seemed that the steering wheel had almost no effect on the car's turning. The car seemed to have been programmed to complete a SPIN before stopping, and no matter how low the speed had dropped or how you tried to save the car, there was no change.

I have never encountered a similar situation in any other SIM before. Maybe it's caused by the grip of the front tyres is too strong, while friction of grass is too weak, which makes this abnormal.

 

Well, it's a very short clip and it looks fine to me.
Tyres covered in offtrack grass will likely have less grip for a short time.

 

Well you have already identified that the front gripped the track while rears still had lack of grip . And you were travelling pretty fast still . So there’s not much grass can offer to stop the rear from continuing at its velocity.
Maybe the rate of grip regain is potentially a little high , but it was consistent between front and rear .

 

Like you said, the grip in the front looks a lot stronger, so the fronts grip up when you hit tarmac and there is just not enough grip for rear, so it just flips like that as you would so some handbrake turn.

Looks kinda funny though, as if the tarmac would had less friction that the grass (maybe the grass covered tires has somehow less grip on tarmac than on grass... ).

Even if there would be something wrong, it's definitely not some common occurance and personally, if I go off track on grass and are coming back, I'm being extra careful,. We don't see any inputs from you here, so it's impossible to say for sure did you do anything that could had contributed in that spin, like applying just a bit of extra throttle or brake at the wrong time or something.

ps. saying a spin is "programmed" is a bit of a tinfoil hat style of claim... it's a sim and no self-respecting sim developer would program something like that, at worst it's some side-effect or bug

 

That's precisely the case by the looks of it. The car travels at the angle, front tires get caught by grippier tarmac whilst the rear continues to spin on the grass resulting in the rear overtaking the front. Seems plausible to me.

 

It is precisely because I have encountered such uncontrollable situations too many times that I have been particularly careful in my operations. I'm pretty sure I didn't have any pedal input on the grass and tried multiple times countersteer to save the car, but as you can see, the car seemed to have completed a written program like SPIN before stopping. And I have never encountered such a situation in the LMU ACC and other simulators I have played before. Perhaps it is due to the wrong friction setting between the grass and the track that caused this. Anyway, I hope to solve this problem. It feels really strange when encountering this situation

 

i do agree it looks strange, that speeding up the right when you end up in the tarmac, especially if there wasn’t any extra throttle input. I’m not sure what could accelerate it like that, looks like as the car is moving from tarmac to grass or ice and not the other way around.

I have had some experiences of something like that, where it felt like the speed of the rear spinning would increase during the spin momentarily without any good reason, but this was over a year ago …

I wonder could there be something with the kerb causing the “push”, or maybe tires dirty wirh grass en up having temporarily less grip on tarmac than there is with same tires on grass (maybe the tires being covered with grass effect is not applied on grass but is applied on tarmac.?.)

Would be nice some physics dev see this and could give some possible explanation?


Ps. Sometimes it feels the rear tires regain grip too slowly when you spin in ams2, doing often the Verstappen like 360 or more instead of 90-180 degrees that you might expect with the speed you are spinning in (and why those slow tank slapper spins feel a bit weird .. not the part that why you ended up spinning, but how long it takes the rear stop spinning ..)

 

Chase cam is never the best way to access the behaviour imo, it alway looks a bit unnatural in movement because of the static car and camera rotation acceleration.
It would have been better to use normal action shot and cockpit .
But the crux of the issue seems to be op being used to other sims that can feel like driving on grass at 20 kph .
Like this example from the gold standard of RF2
https://youtube.com/clip/UgkxzRpaG6Oj9_uyw2MKgrv-FFKOhao_Pqxk?si=Wu14AkTOxthJ4kr2

 

EXACTLY!
Not only regain grip too slowly when spin, but also when recover from an unstable state. Even when exit corners, it will take longer time to regain grip to accelerate compare to other SIM.

Due to the limitations of AMS2's video replay system, I couldn't find a better way to recreate the situation at that time. However, did feel very strange. When rejion the track, it was like the rear of the car was kicked, with a strange acceleration, and countersteer did nothing to the car at all.

I have watched the video of RF2 you sent, the action of the car returning from the grass to the track is reasonable, without strange spin.
When the car slides on the grass like that, we will instinctively countersteer to save the car. The car's energy decreases during the sliding, and when it returns to the track, it will further reduce its energy due to the restoration of grip and countersteer, and get stable.
This is also a situation that occurred when I encountered similar mistakes in other SIM cards, which is intuitive.

 

This rf2 video shows a very unrealistic level of control and grip on the grass.
The hugely powerful and highly downforce dependent rear end with massively wide tires, somehow is able to sustain an acute angle on the grass at high speed .
It should have been turned fully around and gone backwards into the wall.

usually big wide tyres are actually far worse on slippery surfaces like grass and dirt as while they benefit from that extra contact patch on the tarmac , it’s will be the opposite on slippery surface. the larger footprint with low friction is harder to recover .

It never should have made it back to the track let alone display such decorum rejoining.

so if this is what your expectations are then perhaps you haven’t experienced much driving outside of other sims ??

while Ams2 grass can be very unforgiving it’s much closer to reality than this example.

In your example you were already on the verge of rotating all the way around when the front tires returned to the track and recovered some friction.

btw.. there’s is a few cameras available in replay that can be found using keyboard shortcuts.

 

Perhaps for the speed in the video you posted, the grip of the grass is too strong, but the direction of the car is in line with my understanding of inertia and force. However, in my video, the speed of rushing onto the grass is only about 80KM/H, and when returning to the track, it is less than 50KM/H. It's hard for me to understand why the car continues to lose control and cannot regain control at such low speed. I have also encountered similar examples in ACC and LMU, but never spin like that. BTW, the most counterintuitive thing for me is the acceleration at the rear of the car when I return to the track, which feels like an additional force.
You may think that the front tyres regain grip earlier than the rear wheels, but after the rear tyres also touched the track, the car continued to spin for a while, and any opertion to the steering wheel did not work.
If I encounter a similar situation again, I will record several different cameras

 

I would suggest that you are underestimating the speed that can be maintained in grass and how much time is required to halt a slide at even 50kph. Sometimes cars can pick up speed sliding in grass if perpendicular to direction of momentum.

that’s why it’s always best to try and keep the car straight and keep off the throttle when entering grass.
trying to turn and accelerate is going to end in loss of control . If you coast and only apply very small steering input the cars are very controllable.
but if you already in a slide / spin the momentum will carry on trying to pivot around the front tyres , but while they benefit from front tyres have no grip on grass they will slide together for a period, and elongate the spin .

 

When I rushed onto the grass, my car was in first gear, GT3 Porshe 992.

 

that doesn’t really mean anything. It’s more than capable of doing 100kph in first gear probably. and if you tried to steer back to track and applying throttle, it’s no surprise that you ended up sideways.
also when the car re-enters track, the rear is sliding perpendicular to track and coming off a raised curb , so for a split second it would not have had weight loaded contact with track which could explain a moment of spin acceleration. but I don’t think the time the rear come to a halt was delayed at all . You’re talking about a momentum mass of over a tonne moving at probably 50kph .

 

Please read my description carefully. I have emphasized multiple times that no pedal input during the entire process, and it was me who was in the car. I also suggest that you understand the speed of each gear of PORSHE992. Generally, you need to upshift to 2 at 80KM/H.
I think we should stop making meaningless speculations and face the problem. Perhaps next time I should record the speedometer.

 

I only said probably, which means rough guessing. And it’s still not that far off .
Your video doesn’t show anything apart from the aftermath of an off track excursion.
We can’t tell how you ended up sideways , so can only assume you had the rear wheels under power at some stage earlier in incident when running wide into grass . Unless you had already got sideways on track before entering grass . But either way you were sideways in a rotation , in the grass , and the rotation completed when returning to track .
If you have ever driven on grass irl at above 30-40kph , you will know that it’s fairly easy to control in a straight ahead direction, but all bets are off once your sideways . And this is may experience in game as well as hurtling around in a paddock irl.
It’s only going to be exasperated by a large slick tyre and a car with most of its inertia coming from a rearward position.

 

Some sage advice from a fellow countryman.
I feel like Ams2 is a mix of all three examples. But maybe could do with 5-10% more friction from grass .
And the throttle is alot more sensitive as well as we all know .

 

When a topic keeps coming back, there might be a reason. Make me giggle to see this poping up every other months. You're not alone. Just have to get used to the game engine, won't change.