As the first entry after the Equality Constraints post, we will perform the derivation of the Point-to-Point constraint, which models a Revolute Joint, in 2D.

After the first release of the dyn4j project, I felt that it would be good to pass along what I learned about constrained dynamics. This is not an easy subject and aside from purchasing books there’s not much information out there about it for those of us not accustomed to reading research papers or theses. […]