Category: Robotics

Where a planar arm can and cannot reach, where its two solutions collapse into one, and how much reach you give up once you also fix the orientation of the tip — explained with diagrams you can drag.

Forward kinematics turns joint angles into a tip position, and inverse kinematics goes back the other way. Both are explained here with a planar arm you can drag: why the forward direction has exactly one answer, why the inverse one has two, and what a third link buys you.