Fragility of the hatchback

I imagine you've noticed just how much more 'fragile' the hatchback frame is in comparison with most other vehicles, surpassed only by the default van's rear bay when crushed via the roof or rear... I'd love to see this degree of flexibility made available to the other vehicles, which seem unreasonably sturdy when compared to real vehicle crashes.

I've yet to look into the mechanics that put the vehicle together - could anyone explain to me what it is about the hatchback's design that makes it so much 'softer' than the others?

Example:

http://screencast.com/t/X2SSpRRwf

 

look at this:
In-Game-Replica-of-a-Real-120mph-Crash-%28video%29

then compare the Grand marshal @30 mph to this:
https://www.youtube.com/watch?v=JEKBHCxOODo

Furthermore, in your example shot, the pickup would get virtually no damage in reality compared to the damage obtained by the hatch as it owuld just push the hatch along. If the hatch had weighed more than the pick-up then the pick-up would sustain considerably more damage.

I think it's pretty accurate to be honest.

 

You're seeing what you want to see.

Measure the proportion of the car that remains recognisable in the direct comparison video - the BeamNG simulation retains the majority of the passenger compartment as hollow space - even the hatchback behaves in this manner against head-on collisions - my guess would be due to the unrealistic sturdiness of the car's base. BeamNG almost seems to correspond to the idealised operation of the 'crumple zone' of modern cars, absorbing all impact at the tail or nose of the vehicle while keeping the core intact - but as the video shows, at extreme speeds this is far from the case - the presenter comments "... and the passengers? Don't ask.". The interior is completely crushed into the rear.

While I don't see the relevance of the 30mph crash video, given that we're discussing the deformation of the core of the vehicle, something that will only occur at extreme speeds or under great force.

The image included was merely to exhibit how 'soft' that car is in terms of its passenger comparment compressing far more easily. We're not, as such, exploring 'crash' mechanics here, merely why the passenger compartments of most current BeamNG vehicles act as though they have a titanium skeleton.

https://www.youtube.com/watch?v=XFkn37BDvTw

Here's another nice example akin to the comparison video that once again shows high speed crashes compressing the front of the vehicle into and through the passenger comparment, leaving only a mashed front-end that only becomes recognisable at around the rear wheels.

Strongly suspecting it's the base frame of the car refusing to 'crush' under extreme stress that lends these vehicles the unrealistic sturdiness.

You can compress it, you just need to be going at about 300mph to do it. Too sturdy!

 

I don't want to enter into an argument and can see that you've convinced yourself your right so I'm just going to back down and post one last thing. The Developers of this game get 1 of these threads every two days and consistently provide evidence to disprove them. The physics is simulating what would happen very accuratly. Just because the grand-marshal doesn't crumple like whatever your car is doesn't mean it's wrong. All I see is that the GrandMarshall Crumples in a way I would expect it to when it crashes and that's good enough for me. I noticed you said you hadn't looked into vehicle mechanics yet, i advise you do and learn about J-Beam and how it works. You may learn something that will change your mind.

Rob

 

Ermrnrmnn. Words. Tolerance and patience.

I'm talking about the hatchback, formally the Ibishu Covet if I remember correctly, and how its passenger compartment is *better* at total softbody collapse than most of the other vehicles (albeit still not realistic, in that it doesn't collapse the same way vehicles do in the videos we've both posted) , and asking why this is. I'm not sure where you're going with it.

Back to the topic, please - hoping for further replies. What is it about this frame that differs from the others, and what can be done to enable the collapse of the passenger compartment as in real high-speed crashes into solid objects? Despite safety reinforcement the 'hollow space' in the vehicle cab is an obvious weak point, and under sufficient stress will collapse, and this is one minor weakness of BeamNGs simulation at this point - it takes a lot more to inflict that upon one of these vehicles in the sim than it does in real life in terms of velocity at time of impact.

 

While I do take issue with the way the nose of a car is prone to crumpling as if the engine isn't there sometimes there's not much else 'wrong' with the way it crumples. if you cycle through debugging with K then you'll see the very reason it behaves the way it does.

Gabester went and build the car's structure as close to a real one as possible, put in the right material strengths and compared the behavior to the years of researching car crashes he's put in. It seems to work really well because he's finding that when you have something unrealistic in the simulation, such as unrealistically heavy tires, it affects the vehicle behavior in an unrealistic way. Make it more true to reality and suddenly you have a more "true" simulation. I wouldn't call it a fallacy to ask you to trust the simulation based on that kind of track record.

anyway, there's a few things to bear in mind. Most cars in-game top out around 90 or 100ish because of their Tyre model bug, which should be fixed in the next update, so the crash test of the focus and the simulation of the covet aren't the same scenario. There's also something to bear in mind. When you compress an object then the more you crush it the more it will resist being crushed, the physics involved in a car crash aren't "simple" and not something an armchair physicist can work out. Hell, even as an engineer I'd struggle to tell you how and why something simple like a soda can would behave under stress.

when it comes to the covet, find a car like a Suzuki Swift to compare it with. maybe even show us exactly what's wrong.

 

http://www.youtube.com/watch?v=v6HApm20oCg
http://www.youtube.com/watch?v=N9Ubc2VwIDs

these aren't the exact same scenarios of course but they show how the cars crush

 

tell me whats wrong, I've tried my best to match the circumstances, the side impact done at 40mph and well... I could really only pull the pole impact off at 45 trying to throw the hatch off the bed of the pickup.

 

I can't tell why everyone feels a need to defend Drive/gabester's work in this manner when it isn't under attack - I'm complimenting the physics while asking for information and trying to provoke discussion of core-body crash physics, i.e. the collapse of the passenger space in extreme crashes, the one area that differs significantly in comparison with real-world test videos.

Consider the topic abandoned by the OP, I've no interest in repeating myself again.

 

I don't mind but I can't see much wrong with the physics. I even went the length of trying to replicate those crashes to ask what 'exactly' you're seeing that's wrong, because the deformation I saw was pretty much what I saw in the video.

 

I did have doubts myself at start. The cars seemed way too fragile for being crushed at such "low speed" when I first started playing.

But then I started testing various crashes using the debug menu with a speedometer. And then I saw that the game is actually the closest thing to a real crash/racing simulator we've ever had on the gaming market so far.

It makes you respect your speed even more in real life. Once I saw the Gs behind even 60 kmph crashes and the car deformations, I realized it's really out there....

 

I agree with the author, the grand marshal is way too stronk, the pick up isn't, i did crashtests, flippin it and it was really reallistic (it's a pickup..not a city car so it's kinda normal) but the grand marshal...
I mean at a normal speed the deformation is quite good, but there is no difference, or at least not enough, between a crash at 88 mph ( ) and at 120, and i mean that the car isn't deformed in a real way, at that speed there should have nothing left in a frontal crash. And i did my tests against a wall, but if I dare crashing the grand Marshal against a van or a pick up... It is nearly unarmed.
I once saw a van droven by an alcoholic after its crash against an audi a4 (wich is pretty much the category of the grand marshal isn't it ?). The van's driver was driving in the wrong way..on the highway..
Well the van was really damaged, and the driver died btw, but in comparison with the audi... there was nothing left of it except the two rear wheels, all the front part was like a crushed can, out of 5 passengers 4 died. And we all know that germans cars are known for their strength.

 

A frontal crash between 2 cars driving at 60 kmph is the same as a single car going into the wall at 120 kmph.

 

The D15 buckles under a 1.9 ton payload in the back. A truck like that has a 1 ton payload so its
simmilar to life

 

These cars are not real world cars. The covet is an 80s light weight hatchback and it's fragile compared to modern cars (watch top gear uk season 2 episode 1). Game is real as it gets. When you drive in game especially in 3rd person, you're going faster than you are in life since you dont feel the road or your car.

 

Wrong

2 Cars colliding frontal with 60kph is the same as a car crashing a wall with 60kph. Forces do not add up, Newtons 3rd Law.

http://www.youtube.com/watch?v=r8E5dUnLmh4

//Pyrlix

 

No it isn't and I hate this stupid comparison. The cars each 'give' into each other absorbing some of the impact with a head on crash. When hitting a wall, the only thing that 'gives' is the car. The wall will remain where it is.

 

When you look at the video you can clearly see that there is nothing left of the car after the crash against the wall,
test the grand marshal against a wall. You'll see that the seats, the mid part of the vehicle are pretty unarmed.

 

OP is partially right, not because physics suck (or numbers are not put right), but because the crumple zones of a 80's hatchback are not the same as a modern one. What you see in-game is how a modern car will deform in a crash. My uncle is on the road a lot and as you can expect he has been in many crashes. One of them was with an Opel Astra - http://www.auto-bilder.org/autobilder/opel-astra-f-kombi-6787.jpg He managed to crash head-on with another car with 50 km/h. The front part of the car was gone, the steering wheel was smashed to the roof and the engine moved to the passenger seat. Now imagine what happens with 100 km/h or 160 km/h. What you see in these crash test videos are perfect scenarios (perfect weight distribution, car height, etc.). If two identical cars collide, the one that is higher (no brakes pressed, brand-new suspension, etc.) performs better. In reality, things tend to f*ck up a lot.
I'm not saying that it should be fixed, the game is perfect as it its, but I'm pretty sure that this is what the OP meant.

Cheers!

 

This is actually all dam interesting stuff weather OP wanted it or not




Although this version of the truck was built on the 4x4 cab frame i believe, much more sturdy