Robotic weapons and actuators are a must-see item, and popular among manufacturer sets are important for such modern industries. [kthod2000] Have created a design of their own, relying on parts recovered from an old CD-ROM drive.
The arm itself is made up of many elements that appear to be 3D printed, with three main motors visible along its length. These appear to be eject motors collected from several optical drives, which come with a threaded screw on the output shaft which makes them perfect for linear-drive applications. Powered by a TMC2208 driver via a microcontroller, eject motors control the speed of the robot arm at various stages as it moves up and down.
The purpose seems to be to act as a single finger in these three-tier assemblies. Having been ganged up more than once, it could allow a complete five-digit robot to create something like a hand. [kthod2000] Has also done a lot of work towards software that controls hands. The dynamics can all be simulated on the screen simultaneously with the actual motion of the arm.
We’ve seen similar builds before this plotter made of scrap DVD drives. These are a great source of quality electromechanical components for small projects, so it is not surprising to see them working here. Video after the break.