Hello guys/gals, I have a finite volume scheme to calculate the movement of a piece of yarn. This involves dividing the yarn into a number of finite volumes, the center of which is called a node. Collision with surfaces is somewhat of a problem. My integration scheme involves the following steps: Calculate contact : project the position p normally on the surface, p'. Take p = p' Calculate the tension force F acting on a node Calculate the surface reaction. Adjust speed v(old) and force F as below, with (n) the normal and (t) the transversal component: v(old) = v(old)(t) - Beta*v(old)(n), F = F(t) + F(n) + FrictionForce with F(n) = 0 if F(n) is directed into the surface Calculate the new speed of a node : v(new) = v(old) + F*dt/m; Calculate the new position of a node : p(new) = p(old) + v(new)*dt The problem is in some cases this makes the tension force oscillate. Does anyone have an idea on a better method to use for handling collision?