Springs and Losing Energy

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Springs and Losing Energy

Postby mrchinphysics » Sat Mar 28, 2015 4:44 pm

I'm new to Algodoo.

I'm trying to demo a horizontal mass spring system for SHM, but no matter what I do, the system continues to lose energy. [Edit 2: Solved this too. It was air resistance. Toggled that off, and I'm good now. Thanks, I think :oops: ]

Here's the design.
1. Infinite vertical plane and horizontal plane
2. Box dropped onto the horizontal plane
3. Spring connecting box to vertical plane.

I've set spring damping to 0 and friction to 0 for the box and the horizontal plane. I've also set restitution to 1 for the box and the horizontal plane.

But, when I graph KE of the box, the graph over time shows a loss of energy. What do I need to change?

Also, can I graph the sum of the spring potential energy plus the KE of the box on a graph? If so, how? [Edit: Nevermind, figured out how to group the items. Still don't understand why I'm losing energy. Air resistance?]

Thanks.
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Re: Springs and Losing Energy

Postby Kilinich » Sat Mar 28, 2015 6:39 pm

:thumbup:
Dream of Algodoo as game development engine...
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Re: Springs and Losing Energy

Postby groenkees » Thu Jan 23, 2020 5:57 pm

I am facing the same problem with bouncing bodies.
Simple bodies bouncing in a square room don't loose energy but when adding bearings or hinges we see a loss of energy.
There is no air resistance, all materials are set to friction = 0 and restitution = 1

Is this due to limitations of calculation accuracy?
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Re: Springs and Losing Energy

Postby FRA32 » Sat Feb 08, 2020 1:12 am

It has mostly to do with the fact that hinges don't "fixate" an object, instead acting like an elastic pivot, and that elasticity is not 100% energy conserving.
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