Real-Time Physics Simulation Forum

Re: rotation collision response?

2015-09-06T17:33:39+00:00

Is v=w*r a cross product too? is r a vector or magnitude? how to calculate v=wr?(that's crazy if there is vx and vy in 2d)

Statistics: Posted by Isawyou — Sun Sep 06, 2015 5:33 pm

Re: rotation collision response?

2015-09-04T18:37:30+00:00

Good luck!

Statistics: Posted by Dirk Gregorius — Fri Sep 04, 2015 6:37 pm

Re: rotation collision response?

2015-09-04T14:32:43+00:00

I'm doing my best!

Statistics: Posted by Isawyou — Fri Sep 04, 2015 2:32 pm

Re: rotation collision response?

2015-09-04T02:33:17+00:00

You apply equal and opposite impulses at each contact point. Each off center impulse will indeed affect the angular velocity. I don't want to sound offensive, but you might want to study some basic rigid body mechanics before trying to implement a physics engine.

Statistics: Posted by Dirk Gregorius — Fri Sep 04, 2015 2:33 am

Re: rotation collision response?

2015-09-04T00:44:40+00:00

I have two points manifold, should I apply W to them both?
c for center;p1 and p2 contact point ;

-----------------c-----------------
p2_________________ p1

this bar won't fall!

--------------------------c-----------------------
p2|___________| p1

this bar will fall!

Statistics: Posted by Isawyou — Fri Sep 04, 2015 12:44 am

Re: rotation collision response?

2015-09-03T23:37:03+00:00

well! thanks I figure that out!

Statistics: Posted by Isawyou — Thu Sep 03, 2015 11:37 pm

Re: rotation collision response?

2015-09-03T17:51:26+00:00

It looks as if a cross product is missing. It should be r x n. Here is a good derivation:
http://www.essentialmath.com/AngularImpulse.pdf

Statistics: Posted by Dirk Gregorius — Thu Sep 03, 2015 5:51 pm

rotation collision response?

2015-09-02T22:10:07+00:00

Hi all!
when this impulse based equation can equal to zero:
w'=w+(j/I)*r*n;
n normal contact;j impulse;I inertia; from wiki https://en.wikipedia.org/wiki/Collision_response[^]
seems wrong to me;
I'm just talking about center of percussion! what happen to angular velocity?http://labman.phys.utk.edu/phys135/modu ... ge3294.gif it's zero right, not working in impulse based method(and also the sens of angular velocity, I get it always wrong)!
can somebody give a source code about how to calculate angular velocity, or just give me some implementation examples, please I'm lost thanx!

Statistics: Posted by Isawyou — Wed Sep 02, 2015 10:10 pm