Quick Fix Tutorial - Rigid Body Physics Settings Need Help.


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By etourist - 10 Years Ago
I'm new to iClone5 and have been running through the current Quick fix tutorials.

I'm stuck on the first tutorial on Physics where you set up a pile of barrels and then make a jeep drive through them.

I've watched the tutorial over and over, followed it to the letter, starting with a new project and a fresh boot up of iClone 5 (i.e. I haven't adjusted any settings prior to following the steps of the tutorial).

What happens every time is, I set up the stack of 3 high barrels, then add the infinite plane to stop them falling through the floor, when I hit play, my barrels crash to the ground (i.e. the infinite plane) roll all over the place and keep vibrating like they've got a live animal jumping up and down inside them until the player runs out of frames. Even the barrels in the tutorial don't act like that after the jeep runs through them?

Same thing happened when I tried using boxes instead of barrels which leads me to think the default settings on my infinite plane aren't the same as in the tutorial.

I looked to see if anyone else had this issue on the forum before posting but couldn't see anything... anyone have any thoughts or can tell me what the physics settings of the barrels and the infinite plane should be?
By Cricky - 10 Years Ago
Sounds like your World Scale is set too high. Opening the Physics Panel and then clicking on the wrench will display the default which is "5"...reduce it to "2"... You can try to go higher but "2" should do it.

etourist (6/30/2014)
I'm new to iClone5 and have been running through the current Quick fix tutorials.

I'm stuck on the first tutorial on Physics where you set up a pile of barrels and then make a jeep drive through them.

I've watched the tutorial over and over, followed it to the letter, starting with a new project and a fresh boot up of iClone 5 (i.e. I haven't adjusted any settings prior to following the steps of the tutorial).

What happens every time is, I set up the stack of 3 high barrels, then add the infinite plane to stop them falling through the floor, when I hit play, my barrels crash to the ground (i.e. the infinite plane) roll all over the place and keep vibrating like they've got a live animal jumping up and down inside them until the player runs out of frames. Even the barrels in the tutorial don't act like that after the jeep runs through them?

Same thing happened when I tried using boxes instead of barrels which leads me to think the default settings on my infinite plane aren't the same as in the tutorial.

I looked to see if anyone else had this issue on the forum before posting but couldn't see anything... anyone have any thoughts or can tell me what the physics settings of the barrels and the infinite plane should be?
By etourist - 10 Years Ago
Cricky (6/30/2014)
Sounds like your World Scale is set too high. Opening the Physics Panel and then clicking on the wrench will display the default which is "5"...reduce it to "2"... You can try to go higher but "2" should do it.


Thanks, that, for the most part has fixed the problem but I notice my barrels still kind of vibrate before anything has even touched them where as in the demo they sit completely still until the jeep crashes through.

I've tried to adjust them to make sure they are definitely placed one on top of the other, with no gap between each level of barrels. Is there any way you can be certain objects are definitely touching - such as an alignment option perhaps?
By Cricky - 10 Years Ago
etourist (6/30/2014)
Cricky (6/30/2014)
Sounds like your World Scale is set too high. Opening the Physics Panel and then clicking on the wrench will display the default which is "5"...reduce it to "2"... You can try to go higher but "2" should do it.


Thanks, that, for the most part has fixed the problem but I notice my barrels still kind of vibrate before anything has even touched them where as in the demo they sit completely still until the jeep crashes through.

I've tried to adjust them to make sure they are definitely placed one on top of the other, with no gap between each level of barrels. Is there any way you can be certain objects are definitely touching - such as an alignment option perhaps?



The barrels in the demo, are likely just a hair off of each other, so they aren't actually touching. The Physics is likely also set to Frozen and not as a Dynamic prop, meaning they won't react to anything unless they are provoked by force. Dynamic props react to anything that touches or is close to touching them, such as other Dynamic props or Kinematics; "They need their space man" Smile

Check your properties for the barrels and set them to Frozen.

Alignment is simply choosing Pivot point. If using the default barrels, they are already set to Pivot Bottom Center.
By mark - 10 Years Ago
Also make sure you're in the "By Frame" not "Realtime" render mode (next to the Play button) when doing a simulation Wink
By etourist - 10 Years Ago
Cricky (6/30/2014)
The barrels in the demo, are likely just a hair off of each other, so they aren't actually touching. The Physics is likely also set to Frozen and not as a Dynamic prop, meaning they won't react to anything unless they are provoked by force. Dynamic props react to anything that touches or is close to touching them, such as other Dynamic props or Kinematics; "They need their space man" Smile

Check your properties for the barrels and set them to Frozen.

Alignment is simply choosing Pivot point. If using the default barrels, they are already set to Pivot Bottom Center.


Thanks again for that. My barrels were set to dynamic. Changing them to frozen seems to have fixed it. It also works fine with the world scale set back to the default of 5.

Thanks mark for the tip about the "By Frame" render mode, that does seem to make a difference in that my barrels don't seem to be sinking partially below the infinite plane after being knocked over - as they seem to on "Realtime" - why does the render mode affect the barrel physics I wonder?

The quick fix tutorial mentions none of these settings and appears to go with the default settings for almost everything - except the jeep which it shows you how to set up the physics for.

Anyhow much appreciated with the help. I can finally write about this stage of my learning in my blog and move on to the next tutorial.
By mark - 10 Years Ago
I'm guessin' there's a lot going on "calculation-wise" during a physics simulation and the slower things things can go the better for the calculations BigGrin
By etourist - 10 Years Ago
mark (6/30/2014)
I'm guessin' there's a lot going on "calculation-wise" during a physics simulation and the slower things things can go the better for the calculations BigGrin


Sounds about right to me. Smile Thanks again for the help.