Interactive numerical controlled egg-decorating machine

thingiverse

The original egg-bot inspired a new interactive variant for decorating eggs. It is designed to be easily assembled and printed without the need for support if oriented correctly during printing. Controlled via serial interface, it can be connected using Putty or any terminal software. A video demonstration is available at https://www.youtube.com/watch?v=KuiRFXf5oMg. The egg-bot has two modes of operation: direct control with keys like an etch-and-sketch for moving left, right, and rotating forward/reverse, as well as pen up/down functionality; and 360-degree patterns controlled via simple numerical commands (e.g., entering a sequence of numbers selects the pattern, frequency, and width). The pen mount has alternatives: set-screw with captive nut or inserts tailored for the correct pen dimension (https://www.youtube.com/watch?v=yXb-T4F5XGk). The bill of materials includes 3D printed parts (PLA), an Arduino (or standalone atmega328p) with serial connection to a host computer, two driver boards (ULN2003 based), two stepper motors (28BYJ48 DC 5V), a servo (mini 9g), M4 and M5 screws, washers, nuts, a spring, rubber band, "Oogoo" for padding, scrap wood baseplate, and pencils. An optional USB keyboard with stickers can be used as well. Challenges include mitigating backlash in geared steppers through software backlash compensation and using a rubber band for the moving arm. Finding the perfect tension to prevent eggs from slipping while rotating is still being experimented with. The firmware can be found on GitHub at https://github.com/ahd71/incedm.