Kids OK with adultESP32Level 2/3
Talking Key Holder
Walk to the door without your keys and it reminds you. Come home and it welcomes you back.
Kids OK, with an adult
DIY project. Children must build this only with an adult (16+ years) beside them at all times. Not suitable for children under 8 years.
Strictly follow the description given with this video.
Video
The video link will be added here soon.
How it works
- A reed switch in the key hook knows if the keys are hanging.
- The multi-target radar tracks your distance from the door.
- Distance falling = you are leaving; rising = you just arrived.
- The MP3 module speaks the right line: a reminder or a welcome.
Parts you need
- Multi-target mmWave radar sensor (UART)× 1Buy
- ESP32 development board (30-pin)× 1Buy
- Small speaker× 1Buy
- Reed switch + magnet (key hook)× 1Buy
Kit for this projectPrice on request
Get the kitWiring
PowerGroundSignal
| # | From | Connect to |
|---|---|---|
| 1 Power | Radar 5V / GND | 5V / GND rails |
| 2 Signal | Radar TX | ESP32 D13 |
| 3 Signal | Radar RX | ESP32 D14 |
| 4 Power | MP3 VCC / GND (pin 10) | 5V / GND rails |
| 5 Signal | MP3 RX | ESP32 D26 |
| 6 Signal | MP3 TX | ESP32 D25 |
| 7 Signal | MP3 SPK1 / SPK2 | Speaker |
| 8 Signal | Key-hook reed | ESP32 D4 → GND |
3D print files
This project has no 3D-printed parts.
Code
The tested Arduino / ESP32 code for this project will be posted here, ready to copy.