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Rolling coin action

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I do not know if someone has already done. That. I am trying to simulate a coin that is rolling on its side then it spins around, wabbles and stops flat.

I can make the rolling part but the stopping part is tougher. Should i create an action and make it spin and fall by interpolation or should I use muscle?

Thanks.

Pierre

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Muscle animation is for meshes that you need to make some shape-changing change to. A rolling coin wouldn't need to do that. Animating it with bones sounds most likely.

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Muscle animation is for meshes that you need to make some shape-changing change to. A rolling coin wouldn't need to do that. Animating it with bones sounds most likely.

I see...bones would warp the coin i guess..or it would create the illusion. I guess i may have to look on how a coin behave when it rolls and fall.

Thanks for the hint.

Pierre

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You could use Newton Simulation and experiment with the results.

 

Here's a quick try. I made a coin model and a ramp. Coin is positioned above the ramp and made a dynamic object (ramp and ground are made static objects). When the simulation runs, the coin drops, hits the ramp, rolls down it and into the view of the camera.

 

I played with changing the kinetic friction and gravity. (I made the kinetic friction .35 and the Y gravity -6.)

 

With a fair amount of trial and error, you might get what you need.

 

cointest.mov

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Just for fun, I played with just spinning the coin. Here I animated a few key frames to spin the coin around and then the Newton keeps it going for awhile before it comes down.

 

It's a lot of fun just playing around with Newton.

 

coinspin.mov

 

 

One note: Create your coin model with the center at the center axis.

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For control freaks who need to precisely choreograph the coin's death... here's an all manual approach, made easy with bones:

 

CoinRoll_600.mov

 

RollingCoin03.prj

 

 

the "Ground level" bone moves the coin around the center.

 

The "axis" bone is a child of the "Ground level" bone and is the axis of the coin and has two poses. One pose keeps it tilted toward the origin of the "Ground level" bone. The other is a slider that moves it closer to the origin of the "Ground level" bone.

 

I only had to make keyframes at the beginning and the end:

 

the "Ground level" bone turns 1440°, 4 revolutions

the "axis" bone is spun on Z to make the coin "roll" ( I just eyeballed it quickly, it's not exact here.)

the slider moves from 0 to 100 % to move the coin closer to the center.

 

CoinChannels.JPG

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Guys, this is awesome. Robcat, thanks for the project. I am going to study it.

@ largento, could i get your coinspin project to study it too?

Thanks.

Pierre

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Here's a project with the basics. I've put two choreographies in here. One has already had Newton simulated (Newton) and one has everything ready to simulate (Setup).

 

spincoin.prj

 

[EDIT] Here's what the pre-simulated cho looks like:

 

coinspin.mp4

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Here's a project with the basics. I've put two choreographies in here. One has already had Newton simulated (Newton) and one has everything ready to simulate (Setup).

 

spincoin.prj

 

[EDIT] Here's what the pre-simulated cho looks like:

 

coinspin.mp4

Thank you very much. let me study it...a lot i do not know about dynamics. i am going to look through the forum to see if i find tutorials about that.

Pierre

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You could use Newton Simulation and experiment with the results.

 

Here's a quick try. I made a coin model and a ramp. Coin is positioned above the ramp and made a dynamic object (ramp and ground are made static objects). When the simulation runs, the coin drops, hits the ramp, rolls down it and into the view of the camera.

 

I played with changing the kinetic friction and gravity. (I made the kinetic friction .35 and the Y gravity -6.)

 

With a fair amount of trial and error, you might get what you need.

 

cointest.mov

Largento, could I also get this project to look at the dynamic of the rolling coin?

Thank you very much.

Pierre

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Here you go. Same deal. First choreography has the simulation already run, second has everything set up to run.

 

coinroll.prj

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Thanks..I have a question. When you say that the second choregraphy has everything set to run. What do you mean? Can i just substitute my object?

I know about reusable actions, but can a choregraphy setup be reused?

Sincerely,

Pierre

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Using Newton, it actually simulates gravity. So, you set up your choreography and select which objects will be part of the simulation (as static objects or dynamic objects) and then right-click on the choreography in the PWS and go to: Plug-Ins/Simulate Newton. Then the simulation will run and keyframes will be made for every single frame in the length of the choreography.

 

So, in the first one, I've simulated Newton and this has happened. In the second, I haven't. So you can see how I had everything set prior to running the simulation.

 

Once you've run the simulation, you can re-use it. Simply rotate the triangle by the object in the PWS, so that you can dig down to the Choreography Action folder. Right-click it and select "Export as Action..." Then, you can open a new choreography. Bring in the object and drop the action on it.

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Ok, let me work on that on my own to try to figure it out. You already gave me a big help.

Thanks.

P

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I did it in another way.

- created a spiral path, put the Coin move on the path.

- created two separate actions for the Coin, Action1_Spin and Action2_LayDown.

- put these 2 actions to the Coin and changed Action Blend Method to Add.

Actions_BlendMethod.gif

 

- adjust the high of spiral path to keep the Coin touch the Ground.

(frame by frame from start Action2_LayDown to end)

SpinningCoin_LeftSide.gif

 

Camera view.

SpinningCoin_CamView.gif

 

This is the Project file.

CoinTest_a02.prj

 

I think, I will Bake All Action and test with NewtonPhysics.

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That looks great!

Did notice that at the end when the coin comes to rest it seems to lag a bit making it seem like it has air under it, maybe tweek the end a bit.

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Nice solution, Bobby!

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