Portable Electronic Time-Stamping Device Prototype

Project Summary

I need a complete design and working prototype of a portable automatic time-stamping device.
The idea is to combine a mechanical numbering stamp with an electronic system that automatically sets the stamp to the current time (HH:MM).

Main concept
• Use a commercial mechanical numbering stamp (4–6 digits).
• A servo motor rotates the internal gear system to advance one step at a time.
• Upon powering on, the servo rapidly moves the stamp through its steps until it reaches the current time.
• While the device is powered on, the servo advances one step every minute, keeping the printed time synchronized with real time.
• A RTC module (DS3231) provides accurate timekeeping.
• A small digital display (TM1637 or similar) on the top shows the current time.
• Two small push buttons allow manual time adjustment.
• Battery-powered, handheld format.
• A custom 3D-printed enclosure is required to house all components cleanly.
• Final output must be a fully working prototype shipped to me.

What I need
1. Electronics design
• Arduino/ESP microcontroller
• RTC module
• Servo control
• Buttons + display
• Power/battery management
2. Firmware development
• Homing routine
• Detecting a “zero position” (magnet/hall sensor or optical sensor)
• Fast sync at startup
• Continuous minute-by-minute stepping
• Manual time-setting mode
• Error handling (missed steps, desync, etc.)
3. Mechanical design
• Integration with the existing numbering stamp mechanism
• Servo mounting + coupling
• Homing sensor mount
• Full 3D-printed housing (compact, ergonomic)
4. Prototype manufacturing
• Assemble hardware
• Print the enclosure
• Calibrate
• Test functionality
• Ship the final working prototype to me

Deliverables
• Complete working prototype
• All design files (STL/STEP, wiring diagrams, PCB if used)
• Final firmware
• BOM list
• Assembly instructions