Robotic arms are extremely versatile, which is the entire point. But that versatility comes at the cost of complexity when it comes to programming and control. A few years ago, Kelton Serra from the Build Some Stuff YouTube channel simplified the situation by giving his custom robotic arm a puppet-style controller. Now he’s back with a redesigned version of that arm that incorporates many improvements.

Puppet control seems to be gaining popularity, because it is very intuitive. Instead of programming movements and actions, or even directing those with a conventional controller, puppet control works with a special input device that physically mimics the robot. Move a joint on the input device and the robot will move in exactly the same way.

The original version of Serra’s robotic arm had that kind of control input via a scaled-down replica of the arm with potentiometers instead of motors. The new version does, too. However, Serra put years of experience to use when he redesigned the arm, making it more affordable, easier to build, and better performing.

The brain of the robotic arm is an Arduino Nano ESP32 board. It monitors the potentiometers for input, then moves servo motors on the robotic arm to match. The analog voltage output from each potentiometer corresponds to a joint angle. The Arduino controls those servos through a servo driver board.

Most of Serra’s work went into mechanical design and CAD. He put a lot of effort into designing all of the parts to be easily 3D-printable and to make assembly straightforward. He also upgraded the mechanics, including with a belt drive for the wrist joint and a rack-and-pinion for the gripper.

This is a very accessible design that you can construct yourself with a 3D printer and an inexpensive set of components. To do that, head over to the Printables page to grab the files.