How I Made Car Crash Animation in Blender for Moria's Race?

  Blender Dumbass
January 09, 2025

👁 104

https://mastodon.social/ : 👁 18
https://blenderdumbass.org/ : 👁 5
https://blenderdumbass.org/articles/ : 👁 1
https://yandex.ru/ : 👁 13

#MoriasRace #Blender3D #animation #VFX #CGI #3dArt #mastoart #b3d #simulation #cars

License:
Creative Commons Attribution Share-Alike

Not AI Generated! See Proof

Audio Version

More than a year ago already, I released a movie I made called Moria's Race, where on 20th minute this happens:







There are more than one crash in the film. But the most exiting ones happen during the race of the movie. And because this kind of thing was hard for me when I was starting out with Blender, I suppose it will not be a terrible idea to write about how I did it.

Fredy Funny's Crash

Fredy Funny is the character driving the yellow Just 3000 car, which is the only car in the race that has a spoiler for some reason. He is the first one to crash, which happens on 17th minute ( and 11 seconds ). In shot number 2, scene number 10.

Source Files of the Shot




This was the scariest crash scene in the film to make. Before that I made a lazy crash scene with Paps, where The Truck didn't even have a scratch ( despite sparks coming out in every which way ). But this time with Fredy I needed it to be a shocking moment. So I had to do much more.

I was primarily inspired by Spielberg's film Ready Player One where in a beginning of its big race sequence, almost immediately a bunch of cars crash to death in the most brutal way possible ( which I think was exaggerated because Spielberg knew that it was a scene happening in a video game, and so a much stronger level of intensity needs to be present for it to have some level of tension with the audience ).

I was going for as much intensity as I can squeeze out of the movie, while keeping the movie "family friendly". So nobody dies, but for a second it looks like Fredy could have died... and it happens so early on in the race, to establish the tension as fast as possible, so the rest of the race would be taken more seriously.




If you open the source file of the shot ( which I linked above ) you can see that this is not a trivial shot.

There are 6 animated vehicles. All of which contain characters. One of which should be broken into pieces, the glass should break, the metal should deform, the front wheels should dislocate. And the character inside should be smacked so hard, the audience will feel the pain for a moment.




The characters inside of the cars were rather simple. All of them were rigged ( for most of the race ), to have their hands stuck to the steering wheel, with a simple parent constraint. And there is a controller with each car, in front, that both turns the front wheels, side to side, and in the same time turns the steering wheel inside. Basically the entire animation of a character moving the hands to turn the wheel was rigged all the way through, so all I needed is to move the controller and the animation would be done for me.

This of course was hell of a pain in the ass to setup, of course. But it was worth it.




The problem was that until the crash happens, Fredy is also driving the car normally as the rest of them. So he had the same constraints, parenting his hands to the steering wheel, present too. Which would be a problem, since he has to be yanked very hard out of the car.

So to combat this, I animated the "influence" of the constraint, to release over time, over the course of the crash. You can see in the screenshot, the strength of the constraint goes from 1.0 to 0.0 in a course of 7 frames. I didn't animate it faster, so that the hand would not get yanked too jarringly, but 7 frames is jarring enough, for a 24 frames per second movie.




The body of the car is broken into 3 pieces. The main body piece, the door piece, which you could even see being used earlier in the film, and the glass of the door, which has to react to the crash differently than the door itself.

If the door is made out of metal, the door will deform when hitting the tree. The glass, being hard and brittle will instead shutter into pieces. So I have to tackle those things separately.

I could have maybe used Blender soft body or even cloth simulation physics for the body deformation. But I thought that it would be better if I'd deform the car manually.




I did a single shape key inside of blender for both the door and the body, and moved the vertices in such a way that it looked like it hugged the tree. And then over the course of the crash, I animated the Value of this shape key to reveal itself.

The glass was not as simple.




The object that breaks in the movie had a simple modifier setup, with the Explode modifier. The modifier takes the particle simulation of the object, and attaches the polygons of that object to the particles, so they fly in different directions. I've added a simple solidify modifier to it, to give the glass a bit of thickness. And added a crackly material on it. And it shattered very satisfyingly.

The problem is, until a certain frame in the animation it should not shutter. And it should look the same way the glass of this car looked in the rest of the film. So, as you can see in the screenshot, I had two glass objects. One that shutters at a specific frame. And the other that exists before it. And I animated the hide / render buttons in the outliner to make one disappear and the other appear at a specific frame.

The door flanking open and the wheel dislocating was animated manually using regular, good old, keyframes. The same as the main character getting whacked by the tree.

Sharon Lively's Crash

Sharon Lively that drives white Poor Charlie crashes later, by falling down the second loop, taking with her Mike Fast, a heavy metal inspired Gothic driver of Dark Shadow ( my favorite car in Dani's Race ) and Michael Hey who drives a green Underground ( a direct reference to Michael Bay's 6 Underground ).

This was not trivial. The crash happens to 3 cars. Involving 4 ( because Moria happened to drive by the carnage ) and spans 2 shots, not 1.

Shot 25 ( scene 14 ) Source files
Shot 26 ( scene 14 ) Source files

While most of the stuff is done similarly to how I did the Fredy's crash. There are a few differences.

In Sharon's crash, I had to use rigid body simulation for the car's flips and stuff, because she was falling from a very high point and carried enough momentum to send the car spinning. If I tried animating it manually, I'd probably end up with something really bad.




Then there are the completely disconnecting wheels. Which start being parented to the rig, and end up being parented to an object with a rigid body simulation, of those wheels going away. I did it using the old good influence animation on parent constraints.




Though as you can see here I had to bake the simulation to keep it in place.

Sharon, also detaches from the car, similarly to Fredy. But here I made her do a whole flippy flop and slide, so you can tell I had fun animating this shot. And also unlike the Fredy's shot, this one has a ton of sparks. Which were done using very basic particle simulations in blender.




The most fun about the second stage of the crash was that I learned enough how to do it, that I could finally be creative about it. There is this wedging effect happening in the middle of the animation, where the green car wedges into the white car, sending the black can flying.

Also for these two crashes cars had more than one shape key deformation. There are stages in deformation. And I was pretty much improvising them on the fly.

Conclusion

I remember I showed the movie in a gas station once. I literally asked the guy working there to put my movie onto his big screen there for the customers. And he agreed. Anyway... Apart from the infuriating questions from some of them, like "Is this AI?", most strong reactions of the audience was at those two crashes. One person even called me a criminal, for doing so much carnage in my "family friendly" movie. So I believe it worked. It did what it needed to do.

Happy Hacking!!!

Help

Subscribe RSS

Author
Website

Share on Mastodon

Share

Help

Post