Connect LCP equation and Physics
Posted: Mon May 19, 2014 8:33 pm
I've recently been reading up on how to solve for collisions and constraints. But it is a bit difficult for me to grasp what represents what. The papers either don't explain how it is connected to a LCP or they only treat the mathematical side and confuse me with all the math notations and letters that are introduced without explaining what it is they are about.
However the other day I found this presentation (http://goo.gl/84N71q) from Erwin, which does connect the math to the physics. Thank you for that! But still I have a little trouble understanding what the A, lambda and b contain exactly. I understand that A represents the effective mass, lambda the impulses and b the desired velocity change. I do not understand how many lambdas and velocities changes we have. One for each constraints at each contact point?
I've looked at the sequential impulse solver in bullet and from what I understand it updates the velocity of each body for each constraint, which is then again used to determine the needed impulse for the next constraint. But where is this body velocity represented in the LCP equation?
However the other day I found this presentation (http://goo.gl/84N71q) from Erwin, which does connect the math to the physics. Thank you for that! But still I have a little trouble understanding what the A, lambda and b contain exactly. I understand that A represents the effective mass, lambda the impulses and b the desired velocity change. I do not understand how many lambdas and velocities changes we have. One for each constraints at each contact point?
I've looked at the sequential impulse solver in bullet and from what I understand it updates the velocity of each body for each constraint, which is then again used to determine the needed impulse for the next constraint. But where is this body velocity represented in the LCP equation?