# ESP32 Wearable Vibration Alert
## Description
Compact Li-Po powered ESP32 wearable vibration alert prototype for construction worker safety monitoring, using a relay module to directly switch a 3V coin vibration motor with beginner-friendly soldering and labeled PCB wiring.
## Project Details
- **Owner:** luccabellinello
- **Created:** 5/27/2026
- **Last Updated:** 5/27/2026
- **Visibility:** Public
## Key Components
### J1 — [JST B2B PH K 01x02 Connector](https://www.flux.ai/jharwinbarrozo/jst-b2b-ph-k-01x02-connector~zu5.md)
- Role Details: Battery connector for single-cell 3.7V Li-Po input.
- Datasheet URL: https://www.jst-mfg.com/product/pdf/eng/ePH.pdf
- Part Type: Connector
- Role: Power Conversion
- Manufacturer Name: JST Sales America
- Manufacturer Part Number: B2B-PH-K-S(LF)(SN)
**Pins:**
- PIN1 [pin 1]
- PIN2 [pin 2]
### J2 — [0393570004](https://www.flux.ai/adrian95/0393570004~f5d.md)
- License: https://creativecommons.org/licenses/by/4.0/
- Role: Power Conversion
- Connector Gender: Non-Gendered
- Role Details: External MT3608 boost module connector: wire IN+ to switched protected LiPo, IN- to GND, OUT+ adjusted to 5.0V, OUT- to GND. Set MT3608 output to 5.0V before connecting ESP32 and relay.
- Manufacturer Name: Molex
- Manufacturer Part Number: 0393570004
- Connector Rows: 1
- Connector Positions: 4
- Connector Type: Terminal Block
- Connector Pitch: 3.50mm
- Datasheet URL: https://www.molex.com/webdocs/datasheets/pdf/en-us/0393570004_TERMINAL_BLOCKS.pdf
- Part Type: Connector
**Pins:**
- 1 [pin 1]
- 2 [pin 2]
- 3 [pin 3]
- 4 [pin 4]
### K1 — [KY-019](https://www.flux.ai/vasyl/ky-019~t4.md)
- Manufacturer Part Number: KY-019
- Part Type: Relay Module
- Role: Switching
- Role Details: Relay module input is driven by ESP32 GPIO; relay contacts directly switch the motor supply, with no discrete MOSFET/transistor motor driver.
- Datasheet URL: https://datasheet.lcsc.com/lcsc/1811021933_Ningbo-Songle-Relay-SRD-05VDC-SL-C_C35449.pdf
- Manufacturer Name: Keyes SR1
**Pins:**
- COM [pin COM]
- GND [pin A2]
- NC [pin NC]
- NO [pin NO]
- Signal
- VCC [pin A1]
### M1 — [Z3OC1T8219731](https://www.flux.ai/lcsc/z3oc1t8219731~1jvo.md)
- Part Type: Micro Motor & Motor
- JLCPCB Part Class: Extended Part
- Role Details: 3V-class coin vibration motor powered through relay contacts from the battery/protected output path.
- LCSC Part Number: C2894731
- Package or Case Code: VIBRATING-MOTOR-SMD_3P-C9900001680
- Manufacturer Name: KOTL(金龙机电)
- Rated Speed: 14000±2500rpm
- Operating Temperature: -20~+70℃
- Current Rating: 85mA
- Manufacturer Part Number: Z3OC1T8219731
- Voltage Rating: 2.7V
- Role: Switching
**Pins:**
- - [pin 2]
- + [pin 1]
- EP [pin 3]
### SW1 — [Slide Switch SW_SPDT](https://www.flux.ai/404src/slide-switch-swspdt~nq.md)
- Datasheet URL: https://www.taydaelectronics.com/datasheets/A-5111.pdf
- Role Details: Disconnects protected battery output from the boost and relay/motor supply path.
- Purchase Url: https://www.taydaelectronics.com/slide-switch-1p2t-through-hole-0-5a-50vdc.html
- Role: Switching
- Manufacturer Name: Wealth Metal
- Manufacturer Part Number: SS12F44G5
**Pins:**
- A [pin 1]
- B [pin 2]
- C [pin 3]
### U1 — [ESP32-DEVKITC](https://www.flux.ai/vasy_skral/esp32-devkitc~7mc.md)
- Datasheet URL: http://espressif.com/sites/default/files/documentation/esp32_datasheet_en.pdf
- Role Details: Main MCU; GPIO controls relay module, status LED, and optional test button.
- Role: Controller
- License: https://creativecommons.org/licenses/by/4.0/
- Part Type: Development Boards
- Symbol Style: Parametric
- Manufacturer Part Number: ESP32-DEVKITC
- Manufacturer Name: Espressif Systems
**Pins:**
- 3V3 [pin 1]
- CLK [pin 20]
- CMD [pin 18]
- EN [pin 2]
- EXT_5V [pin 19]
- GND1 [pin 14]
- GND2 [pin 32]
- GND3 [pin 38]
- IO0 [pin 25]
- IO12 [pin 13]
- IO13 [pin 15]
- IO14 [pin 12]
- IO15 [pin 23]
- IO16 [pin 27]
- IO17 [pin 28]
- IO18 [pin 30]
- IO19 [pin 31]
- IO2 [pin 24]
- IO21 [pin 33]
- IO22 [pin 36]
- IO23 [pin 37]
- IO25 [pin 9]
- IO26 [pin 10]
- IO27 [pin 11]
- IO32 [pin 7]
- IO33 [pin 8]
- IO34 [pin 5]
- IO35 [pin 6]
- IO4 [pin 26]
- IO5 [pin 29]
- RXD0 [pin 34]
- SD0 [pin 21]
- SD1 [pin 22]
- SD2 [pin 16]
- SD3 [pin 17]
- SENSOR_VN [pin 4]
- SENSOR_VP [pin 3]
- TXD0 [pin 35]
### U2 — [TP4056_Module](https://www.flux.ai/wolfxpac/tp4056module~ap.md)
- License: https://creativecommons.org/licenses/by/4.0/
- Manufacturer Name: Generic
- Role: Power Conversion
- Part Type: Module
- Role Details: 1-cell Li-Po charger/protection module; battery and protected output interface.
- Datasheet URL: https://robocraze.com/products/tp4056-lithium-battery-charging-board
**Pins:**
- BAT- [pin 5]
- BAT+ [pin 6]
- IN- [pin 1]
- IN+ [pin 2]
- OUT- [pin 3]
- OUT+ [pin 4]
*The full schematic, PCB layout, bill of materials, and interactive design are available at [https://www.flux.ai/luccabellinello/esp32-wearable-vibration-alert~hg](https://www.flux.ai/luccabellinello/esp32-wearable-vibration-alert~hg).*
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*Generated from [https://www.flux.ai/luccabellinello/esp32-wearable-vibration-alert~hg](https://www.flux.ai/luccabellinello/esp32-wearable-vibration-alert~hg)*