Smart Mouthguard Device – Impact & Motion Sensing Platform

This project is a compact, high-precision wearable in the form of a mouthguard, designed to capture and transmit motion and impact data in real time for applications in sports safety, athletic performance monitoring, and research. The system integrates advanced sensing, low-power wireless communication, and robust power management into a lightweight, ergonomic design suitable for prolonged use during training and competition.

Core Processing & Communication

At the heart of the device is the Nordic Semiconductor nRF52832 Bluetooth Low Energy (BLE) microcontroller. This SoC combines a 64 MHz ARM Cortex-M4 CPU, integrated BLE transceiver, and low-power architecture, enabling continuous data acquisition and wireless transmission to smartphones, tablets, or edge gateways without compromising battery life.

Multi-Axis Motion Sensing

To achieve high accuracy and redundancy in motion capture, the device incorporates three Bosch Sensortec BMI323 accelerometers, each capable of detecting linear acceleration and orientation changes across three axes. By strategically positioning the sensors, the system ensures:

• Precise detection of impact magnitude, direction, and frequency
• Improved reliability through cross-sensor data correlation
• Capability to distinguish between sports-related impacts and non-critical movements

These measurements can be processed locally or streamed in real time for analysis using external applications.

Power Management & Battery System

The device’s energy architecture is optimized for safety, efficiency, and compactness:

• BQ25175 – High-efficiency linear battery charger for single-cell lithium-ion chemistry
• RP605Z334 – Low-noise, high-stability voltage regulator for consistent MCU and sensor supply
• BQ29707 – Battery protection IC safeguarding against over-voltage, under-voltage, and over-current events
• EFC4626R – Low-Rds(on) MOSFET for power switching and load control

A tiny rechargeable lithium-ion battery is integrated into the mouthguard body, providing several hours of continuous operation. Charging and wired communication are facilitated by a micro USB port for user convenience.

Design & Ergonomics

The mouthguard’s internal electronics are encapsulated to protect against moisture and mechanical stress. The housing is shaped to ensure a comfortable fit, even during intense physical activity, while maintaining direct contact stability for accurate motion sensing.

Patent-Based Innovations

This design draws on principles from patent WO2021248191A1, which describes optimized placement of inertial sensors within mouthguards, wireless data transmission strategies, and algorithms for impact classification and event logging. These enhancements enable:

• Distinction between rotational and linear accelerations
• Identification of potentially dangerous impacts for concussion risk analysis
• Long-term data logging for player performance and safety statistics

Applications

• Sports safety – Monitoring head impacts in contact sports (rugby, boxing, hockey, American football)
• Performance analysis – Studying motion efficiency and biomechanical patterns
• Medical research – Supporting concussion and TBI (traumatic brain injury) studies
• Real-time alerts – Enabling instant intervention from coaches or medical staff