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Adams Issue

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F13jmagill

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Unread post Tue Dec 10, 2013 3:42 pm

Adams Issue

Professor/Justin,

I am having an issue with adams that two parts seem to go "through" each other. I am simulating a ball dropping into an array of pegs (with walls to contain). I constrained the pegs with fixed joints and let gravity take the ball but when I simulate, the ball goes straight through the pegs and walls (all parts have a mass). Any suggestions?

Thank you,

Josh
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JustinM

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Unread post Tue Dec 10, 2013 6:18 pm

Re: Adams Issue

Define a solid contact between any bodies that may collide, in this case between each peg and the ball. But you don't need contacts between each peg. You can do this manually, or I know of a way to use the command language to write a loop to create a lot of contacts between the pegs and the body if you have 1000's of pegs.

Justin
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F13jmagill

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Joined: Thu Aug 29, 2013 3:46 pm

Unread post Wed Dec 11, 2013 12:37 pm

Re: Adams Issue

Justin,

I only have 30 pegs so it's not too big of a deal setting the contact forces individually. However, I've set sphere to sphere contacts (simplifying the pegs to spheres, justified by simplifying the system to two dimensional), and the ball still falls right through the pegs. Any thoughts?

Thanks in advance,

Josh
<<

F13jmagill

Newbie
Newbie

Posts: 18

Joined: Thu Aug 29, 2013 3:46 pm

Unread post Wed Dec 11, 2013 12:42 pm

Re: Adams Issue

Hold the phone! I tried decreasing the simulation time and increasing the number of steps, which fixed it. I'm not entirely sure why this would do it (I understand why it would increase accuracy but not change from completely missing the contact force to having it), but I'm not going to argue with success. :)

Josh

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