I have this 4 particles, each particle has a mass of 1.

The particles are connected with a black bar that transfers the instant force to other particles instantly.

If the particle that is connected to the other 3 feels a force upwards what is the instant vector force felt by the others.

I know how to solve this problem if there was only two particles connected by a black bar but when there are many particles connected I can't figure out how to distribute the force to the other particles.

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my preview solutions are wrong, my second solution was stupid wrong but it works in my iteration algorithm very well, that's why it put it

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I know how to solve this problem if there was only two particles connected by a black bar but when there are many particles connected I can't figure out how to distribute the force to the other particles.

I think you need to take 3 steps.

1. Compute transfered force between individual particles while isolating other connections.

2. Net the distribution starting at the 1st-order nodes (most immediately affected by force)

3. Re-weight (like, normalize) all of the forces.

By "starting at 1st-order nodes" I was referring to the breadth-first nature of transfering force through a mesh. Of course if you have a case as simple as this, you don't need to worry about that.

"Net the distribution"

This can mean lots of things, describe that more, plz

ya I am already using that, and I am adding the ability of indestructible, undeformable joints so I want to solve this problem

*nop, indestructible, undeformable joints can't be made by just adding more iterations

*In my app the number of iterations is limited.

*If one particle has many joints it will turn explosive.

*This problem solves the explosiveness too.(and that's actually the principal reason I am using this method, a little bit modified to still have some jiggling)

Hello Lomateron,

I've been working on the exact same problem, but I haven't solved it entirely yet. I've attached a small windows .exe + full source for a small program that propagates forces trough a chain of interconnected particles. It displays far more rigid behaviour than any iterative solver I know of. My method of doing this is very similar to yours, it seems :-)

The only problem is that it's position based, and does not take velocity and acceleration into consideration. Still working on that...

Cheers,

Mike

If I understand you correctly you have a compound object of 4 elements . You need to compute the new innertia tensor of the compounded object from those colapsed 4 elements. And apply forces over this new inertia tensor.

In case of 2 elements compound object, the innertia tensor of compounded object is (Ait - Bit)*massB/(massA *2) in space of the compound object.