Hybrid Clock - Mechanical Fusion of Digital and Analog Clocks

A 3D-printed clock featuring both digital and analog displays with the following characteristics:

• Both the digital and analog displays are driven by a single motor.
• The current time is automatically acquired and adjusted via WiFi.
• A sensorless origin-finding mechanism.
• Designed for wall mounting with a slim depth of just 50mm.
• A clean appearance achieved through multi-material 3D printing.

Limitation: The minute hand moves once every 10 minutes. In other words, the time resolution of the analog clock is 10 minutes.

Update March 17, 2025 : Analog clock priority mode is added to the source code. The 3D model is not changed at all.

Video

Supplies

Material

• Motor : 28BYJ-48 geared stepper motor and driver board comes with (around 3USD per unit) . You can find at Amazon, AliExpress 
• Microcontroller : Seeed Studio XIAO ESP32C6 without pin headers 
  • You could use any other ESP32-based microcontrollers
• Screws : Assortment of 2mm flat head tapping screws. You can find at Amazon, AliExpress 
• Lubricant (silicone oil spray)

Tool

• Screw driver
• Soldering iron
• Drill bits (1.5mm and 2mm)
• Knife, scraper and/or file to remove debris, smoothen surfaces and chamfer corners of printed matter PC with Arduino IDE

Print colored Parts

Printing tips

• Print all parts with supplied posture.
• Only "1min-rotor.stl" needs support structure (at the hook part only).

Parts paring (base-color, vivid-color)

• 1min-rotor.stl, 1min-rotor-letters.stl
• 10min-rotor.stl,  10min-rotor-letters.stl
• hour-rotor.stl, hour-rotor-letters.stl
• 10min-axis.stl, 10min-axis-hand.stl
• front-frame-white.stl, front-frame-colored.stl

For multi-material 3D printers

• Arrange paired models as assembly
• Give different colors for "-letters", "-hand" and "-colored" files

For usual single-material FDM printers

• Change filament during print using "pause at height" function of your slicer.
• Only rotors can give multiple colors in this case. "front-frame" and "10min-axis" are in single color.

Print Single-colored Parts

Printing tips

• Print all parts with supplied posture.
• Support structures are not necessary.

Assemble

• Before assembly, clean surfaces touching to the other parts by files or scrapers. It may affect to the smoothness of the motion.
• Clean holes with drill bits.
• For screw through-holes, use 2mm drill.
• For screw tightening holes, use 1.5 - 1.6mm drill.
• You do not need glues.
• Please be aware of the rotational alignments of the parts (hour rotor and 10min-hand axis).

Electronics and Codes

Hardware

• Remove ULN2003 IC in prior to make more space for soldering.
• It is recommended to trim (cut) the four pins of pin header of ULN2003 driver board for the ease of soldering. 
• Please solder the Seeed Studio XIAO ESP32C6 microcontroller upside down.
• Solder pins (D1-D4 of Seeed Studio XIAO ESP32C6) to the input of driver board directly.
• Solder wires from 5V and GND to the driver board.
• The other type of ESP32-based board could be used also, but the port mapping in the source code should be changed.
• The case model is only for XIAO ESP32C6. The excess motor cable can be stored in the case also.

Software

• Install "WiFiManager" library by tzapu to your Arduino IDE using library manager. It is necessary for configuring WiFi connection using your smartphones.
  • Just search with keyword "wifimanager" in library manager, and click "install".
• Compile and flash the demo-xiao.ino (below) to your microcontroller using Arduino IDE, and confirm that the digit shows time from 12:00 to 11:59 sequentially.
• Then compile and Flash the clock-xiao.ino (below), the clock code with WiFi sync.
  • Before compile, set your timezone at line #9 of the source code. The code of your timezone can be found at https://github.com/nayarsystems/posix_tz_db/blob/master/zones.csv

WiFi Configuration

The WiFi configuration can be performed by your smartphone.

• Connect to the WiFi station named "Hybrid Clock"
• Configuration window may open. If not, please access to http://192.168.4.1 by your web browser.
• Select your WiFi access point (2.4GHz only) and enter password.
• Tap "Save" and all set!

Analog Clock Priority Mode

This mode shows precise time (1minute resolution) on analog clock. Instead, the alignment of digital clock is cluttered. The image above is an example showing 10:24 in analog clock priority mode.

To turn on this mode, change the definition of PRIORITY_ANALOG (line 12 in the source code) from false to true.

Category: Gadgets