This arm is a project for an engineering class at Swarthmore College.
My lab partner Katherine and I (Ames) improved this arm (it was from a previous project) and wrote controlling software for it. We used Processing to write a friendly GUI that allows the user to either draw with the mouse, or import SVG path data from a file. The software will then trace the paths and send the angles to the servos of the robotic arm.
The arm isn't perfectly rigid and the servos aren't perfect either, so it's a little sloppy, but it works better than it used to.
The project wiki: wikis.swarthmore.edu/ENGR005_2008/index.php/Robotic_Arm_2.0
Swarthmore Engineering: engin.swarthmore.edu