TAP Ring Prototype - Wireless Charger & Firmware Development
Budget: $1,500 – $3,000 USD
Product: TAP Ring (Threat Alert Protection) — wearable safety ring
Deliverable: 3-5 working bench prototypes
TAP Ring — Flex PCB Bring-Up: Wireless Charger, Battery, Firmware Flash, BLE Tap Test
Background
Client has 20 assembled 4L flex PCB strips (AlteraFlex) + batteries + DigiKey parts. Manufacturer shipped strips, need charger.
Scope
1. Integrate flex strip + LPCV170727 20 mAh LiPo (protection + 50 mm leads).
2. Wireless charger — build (design provided) a small Qi (or equivalent) charge solution for the ring strip + battery. Client wants wireless charger, not only a wired dock. (Wired MCP73831 + Adafruit USB-C parts are included.)
3. Firmware: Use client J-LINK EDU MINI to flash HJ-531IMF BLE module; document procedure.
4. BLE validation: Prove tap/BLE path works — either:
- Simple BLE scanner / GATT read, or
- Client TapRing Flutter app
5. Final test: Charge ring, Turn on ring by holding down button, connect via BLE from phone, tap button and send time in ms via BLE to phone, send vibrate time in ms to ring, verify vibration, turn off ring by holding button.
## What client supplies
| Item | Qty
|------|-----|
| Assembled 4L flex strips | 20
| LPCV170727 LiPo 3.7V 20mAh | 20
| Adafruit USB-C breakouts | 20
| J-LINK EDU MINI | 1
| TapRing Flutter app | —
| BLE UUID spec | —
Key ICs (on strip)
AT42QT1010 tap sensor, HJ-531IMF BLE, DW01A protection, AP2112K-3.3 LDO, VC0720B001F vibrator.
Milestones
| % | Deliverable |
|---|-------------|
| 20% | Plan: wireless charge topology + firmware flash approach |
| 40% | One strip: battery attached, charges (wireless), powers on |
| 30% | Firmware flashed; BLE tap event visible on phone (app or nRF Connect) |
| 10% | Short test report / video |
Skills
Embedded BLE, LiPo charging (prefer wireless/Qi experience), J-Link/SWD, flex PCB handling, GATT debugging.
Deliverable: 3-5 working bench prototypes
TAP Ring — Flex PCB Bring-Up: Wireless Charger, Battery, Firmware Flash, BLE Tap Test
Background
Client has 20 assembled 4L flex PCB strips (AlteraFlex) + batteries + DigiKey parts. Manufacturer shipped strips, need charger.
Scope
1. Integrate flex strip + LPCV170727 20 mAh LiPo (protection + 50 mm leads).
2. Wireless charger — build (design provided) a small Qi (or equivalent) charge solution for the ring strip + battery. Client wants wireless charger, not only a wired dock. (Wired MCP73831 + Adafruit USB-C parts are included.)
3. Firmware: Use client J-LINK EDU MINI to flash HJ-531IMF BLE module; document procedure.
4. BLE validation: Prove tap/BLE path works — either:
- Simple BLE scanner / GATT read, or
- Client TapRing Flutter app
5. Final test: Charge ring, Turn on ring by holding down button, connect via BLE from phone, tap button and send time in ms via BLE to phone, send vibrate time in ms to ring, verify vibration, turn off ring by holding button.
## What client supplies
| Item | Qty
|------|-----|
| Assembled 4L flex strips | 20
| LPCV170727 LiPo 3.7V 20mAh | 20
| Adafruit USB-C breakouts | 20
| J-LINK EDU MINI | 1
| TapRing Flutter app | —
| BLE UUID spec | —
Key ICs (on strip)
AT42QT1010 tap sensor, HJ-531IMF BLE, DW01A protection, AP2112K-3.3 LDO, VC0720B001F vibrator.
Milestones
| % | Deliverable |
|---|-------------|
| 20% | Plan: wireless charge topology + firmware flash approach |
| 40% | One strip: battery attached, charges (wireless), powers on |
| 30% | Firmware flashed; BLE tap event visible on phone (app or nRF Connect) |
| 10% | Short test report / video |
Skills
Embedded BLE, LiPo charging (prefer wireless/Qi experience), J-Link/SWD, flex PCB handling, GATT debugging.