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________________________________________ Project Summary We are looking for an experienced embedded hardware engineer (or small team) to design and prototype a compact wireless 2-axis tilt sensor for internal R&D use. The module must: • Measure pitch + roll (2-DOF tilt relative to gravity) • Stream values via Bluetooth Low Energy (BLE) • Run on a coin cell or small Li-Po • Deliver 2–5 prototype units This device is not for clinical use—only research & testing. ________________________________________ Key Technical Requirements Sensor • 2-axis tilt (pitch + roll) • Suggested: Murata SCL3300, ST LIS3DSH/LIS2DH, ADIS accelerometer • Accuracy goal: ±0.2° (prototype) Communication • BLE 4.2 or 5.0 • 10–20 Hz tilt streaming • GATT characteristics: pitch, roll, (optional) temperature + battery Power • CR2032 coin cell or small Li-Po • 8–12 hours continuous runtime • Low-power sleep modes Firmware • Sensor drivers • BLE stack • Zeroing/calibration routine • Basic filtering Mechanical • Small PCB + 3D-printed enclosure • Flat mounting surface • Accessible programming header ________________________________________ Deliverables (Milestones) 1. Architecture & Component Selection • Final BOM • Block diagram • Firmware outline 2. Schematic + PCB Layout (Rev A) • 2–4 layer PCB • Gerbers + PnP files • Final BOM with sourcing 3. Firmware MVP • BLE advertisement + streaming • Tilt at 10–20 Hz • Zeroing + filtering 4. Prototype Assembly • 2–5 assembled units • Bring-up + debugging • Source files (Altium/KiCad + firmware) ________________________________________ Regulatory Awareness (Prototype-Level Only) Not for certification, but must follow good practices based on: • IEC 60601-1 (basic electrical safety awareness) • IEC 60601-1-2 (EMC-aware PCB layout) • ISO 14971 (risk considerations like battery safety, BLE loss) • IEC 62304 (clean firmware structure) • FCC/IC (prefer pre-certified BLE modules) ________________________________________ What We’re Looking For • Strong BLE experience (Nordic nRF52 ideal) • IMU/accelerometer integration • Low-power design • PCB layout experience (2–4 layer) • Prototype assembly experience • Good documentation & communication ________________________________________ How to Apply Please include: 1. Brief summary of relevant experience 2. Fixed-price quote with milestone breakdown 3. Estimated timeline 4. Proposed approach (sensor + BLE module + MCU) 5. Portfolio or prior similar projects ________________________________________