My dad loves working on cars — but he's blind, which makes reading the tiny scale markings on a torque wrench pretty much impossible. This project is a simple fix for that: add an Arduino Nano and a Little Buddy Talker speech synthesis chip to a VEVOR click-wrench, and it announces the current torque setting out loud at the press of a button. No squinting at a scale, no asking someone to check — just press and listen.

The Arduino passively monitors the wrench's own ▲ and ▼ buttons via 10 kΩ series resistors, silently tracking the displayed value without interfering with the wrench's own electronics. A single added push-button drives all speech: a short press announces the current setting, a double-tap cycles between three unit modes (ft-lb only → both → N·m only), and a long press resets the tracker.

• Three selectable unit modes: ft-lb only, both, N·m only
• Double-tap speak button to cycle unit mode with audio confirmation
• Single press: announce current torque in active unit mode
• Long press (3 s): sync reset to minimum value
• Passive button monitoring — no interference with wrench electronics
• Handles full range: 25–250 ft-lb (34–340 N·m)
• Speaks any number 0–999 correctly
• Single .ino file, no libraries beyond SPI
• Word tables stored in flash (PROGMEM) to save RAM
• Powered by 9V battery or USB power bank

The series resistors protect the Arduino and prevent loading the wrench MCU. If powered separately from the wrench, tie the GNDs together.

🔴 In progress — firmware is written and tested on the bench. Next step is fitting everything inside the wrench handle and handing it over for real use!