Wearable Healthcare • Child Safety
Child Hydration Awareness and Reminder Wristband
A concept-stage wearable system intended to provide child-friendly hydration reminders through experimental skin-conductance sensing, colour-coded alerts, a loud repeating siren and SMS communication with a parent or guardian.
BRIST-HYDRA is not an open-source project. Its concept, design, documentation, source code, circuit architecture, images and technical material may not be copied, reproduced, modified, redistributed or used commercially without prior written permission, except where permitted by applicable law.
Project Overview
Childhood dehydration and heat-related illness are important concerns during hot weather, sports, outdoor activity and school hours. Children may forget to drink water, while parents and teachers cannot continuously observe every child.
Early warning signs may include tiredness, headache, dizziness, weakness and reduced concentration. Severe fluid loss may contribute to heat-related illness.
BRIST-HYDRA is a child-focused wearable concept using an Arduino UNO Mini, an experimental skin-conductance sensor, RGB indicators, an OLED display, a miniature siren and a SIM800L communication module.
When an experimental sensor value crosses a programmed warning threshold, the device produces local alerts and sends an SMS notification to the registered parent or guardian.
Keywords: Hydration awareness, children, Arduino UNO Mini, skin conductance, wearable sensors, siren and SMS alert.
Current Project Stage
The project is currently at the research, planning and component-identification stage. The principal sensors, compact controller, GSM module, indicators and alert devices have been identified. Procurement will begin soon.
Need for the Project
During hot weather, children may lose fluids through perspiration, sports and outdoor activity. They may also forget to drink water or fail to recognise early discomfort.
Proposed Operation
The first prototype is planned for children aged approximately 5–12 years, subject to safety, comfort and usability evaluation.
The skin-contact sensor records an electrical-conductance value.
The Arduino UNO Mini reads and processes the experimental sensor value.
The reading is compared with calibrated green, yellow and red threshold ranges.
The LED, display and siren provide an immediate warning to the child.
The SIM800L sends an SMS alert to the registered parent or guardian.
The child or supervising adult acknowledges the warning after water has been provided.
The device pauses, records fresh sensor values and resumes the alert if the warning condition remains.
User Warning System
The sensor reading is within the calibrated normal range.
The reading has crossed the first programmed awareness threshold.
The reading has crossed the higher programmed alert threshold.
At the red alert level, BRIST-HYDRA enters a repeating siren mode. The warning continues in loud alert cycles until the child, teacher, parent or supervising adult acknowledges it. This helps prevent the warning from being ignored.
The siren is not described as automatically detecting that water has been swallowed. Instead, acknowledgement confirms that the warning has been attended to. If the programmed alert condition remains after rechecking, the warning resumes.
Wearable Concept
BRIST-HYDRA is planned as a compact wrist-worn unit resembling a digital watch. Skin-contact electrodes would be positioned on the rear surface, while the front would contain a small display, visual indicators and an acknowledgement control.
Hardware Architecture
Preliminary Electronics Plan
The following connections are preliminary and may be modified during prototype development and custom-PCB design.
| Component | Proposed Connection | Purpose |
|---|---|---|
| GSR Sensor | Analog output to Arduino UNO Mini A0 | Provides an experimental skin-conductance reading for threshold analysis. |
| Miniature Siren | Digital control pin through transistor or MOSFET driver | Produces the loud repeating red-level warning without drawing siren current directly from the controller pin. |
| RGB LED | Three suitable digital or PWM outputs | Produces green, yellow and red visual indications. |
| OLED Display | I²C communication lines | Displays status symbols and warning instructions. |
| SIM800L TX | Arduino software-serial receive input | Transfers communication data from the GSM module to the controller. |
| SIM800L RX | Arduino software-serial transmit output through appropriate signal conditioning | Receives AT commands for sending SMS alerts. |
| Acknowledgement Button | Digital input with pull-up configuration | Confirms that the warning has been noticed and temporarily pauses the siren for a recheck. |
| SIM800L Power Circuit | Dedicated regulated battery supply | Supports stable GSM operation without powering the module directly from an Arduino output pin. |
| Rechargeable Battery | Charging, protection and voltage-regulation circuit | Supplies portable power to the wearable system. |
Scientific Basis
A galvanic skin-response or electrodermal-activity sensor records changes in the electrical conductance of the skin. The reading may be influenced by sweat-gland activity, temperature, movement, contact pressure, electrode quality, stress and individual physiology.
In BRIST-HYDRA, this value is being investigated as one possible input for a hydration-awareness and reminder system.
The Arduino UNO Mini repeatedly reads the sensor value and compares it with experimentally calibrated threshold ranges.
The selected alert level controls the display, RGB indicator, siren and SIM800L SMS communication. Red-level alerts remain active until acknowledged, followed by an automatic sensor recheck.
Concept Assessment
These benefits remain design objectives and must be confirmed through prototyping, costing, safety testing and user evaluation.
Planned Development
BRIST-HYDRA received funding support from MAASTEK Technologies for research, component procurement, PCB development, prototyping and future technical advancement.
₹80,000