3D printed 12 Digits Flip (flap) display
Something I made a few months back but hadn’t posted yet. I didn’t document much during the build but sharing a few photos and a fun short video.
This is an alphanumeric display that can be used to print out messages or simply show date and time. It makes some noise but is much quieter and less intrusive than the magnetic flip segment clock I had made a while back.
This is based on existing drum designs that can easily be found out there on the net, but adapted to my own design. I wanted each digit to be its own closed, separate unit. Each unit can hold on to the next using magnets built into the sides, and all the units are linked in series via short cables for power and i2c communication. Each unit has its own ESP32 for control of that unit’s motor, and the whole chain is controlled by a single ESP32 handling the message functionality. The “head” controller manages the whole display by sending orders to each module independently via serial communication. Each module is responsible for handling movement and positioning, and reporting state to the main controller.
Each module has its own custom PCB with a stepper motor driver, an ESP32 unit (S2 mini), and i2c address selector, and connectors for i2c, power, motor, and hall sensor.
It’s easy to switch up the color of each separate unit by printing the front face with a different filament.
Units hooked up to each other using magnets and one short cable.
Web Interface
Last but not least, the main ESP32 module runs a local http server with a simple interface, so the display can be controlled from a web browser to change display mode, send text messages (including multi-line), and a way to set the offset for each unit. Each motor uses a hall sensor and magnet for the zero position, but slight positional differences mean that an offset (number of steps) must be set for each digit independently.
