Arduino controlled mechanical clock

thingiverse

Geared mechanical clock that works by means of a low cost arduino controlled stepper motor. Gears are left at sight, so you can see them moving as time passes. Arduino sw is provided as part of the project. 3D design has been done using OpenSCAD. I provide the OpenSCAD code, just in case you want to remix it. I am sorry most of the comments and names are in Spanish. Added in v0.93: optional table stand. Added in v0.94: assembly animation and errors correction. Added in v0.95: optional circuitry for fast forward and fast reverse buttons, which help setting the clock time BOM: * printed pieces (STLs provided). You will need 4 x spacer to attach the electronics. * Arduino control board (https://www.amazon.com/ELEGOO-Board-ATmega328P-* ATMEGA16U2-Compliant/dp/B01EWOE0UU) * 28byj-48 stepper motor and ULN2003A driver (https://www.amazon.com/Brand-28BYJ-48-Reduction-ULN2003-Stepper/dp/B07YZTMZN2) * Some screws and nuts to tie everything together: Frame and face: 4 x M4 nuts, 1 x M4x30, 1 x M4x15, 2 x M4x40 Stepper motor attachment: 2 x M3 nuts, 2 x M3x8 Electronic stuff attachment: 4 x M3 nuts, 4 x M3x12 * 6 x male-female jumper wires for cabling Arduino to driver connections * Arduino USB cable and power supply BOM for optional fast forward and fast reverse buttons: * 2 x (ON)-OFF, Push-to-make, SPST Momentary switch (https://www.amazon.com/Sub-Mini-Push-Button-Momentary-Switch/dp/B004GIKRNC) * 2 x 4k7 resistors 1/4w (https://www.amazon.com/EDGELEC-Resistor-Tolerance-Resistance-Optional/dp/B07HDFHPP3) * Additional jumper wires for cabling Arduino to push switches I dedicate this project to my 3ºESO (14–15 years old) students in Colegio Alameda de Osuna (Madrid). By the end of last term, I promised them to work in an OpenSCAD/arduino controlled clock during the summer vacations, and here is the result.