Project Hub /Basic Analog & Power Electronics/Battery Chargers & Charging Circuits/Core Posture: Smart IoT Posture Corrector and Hydration Assistant

Core Posture: Smart IoT Posture Corrector and Hydration Assistant

Intermediate

ESP32

₹1,500 – ₹5,000

3 – 6 Hours

Partial Kit

Core Posture: Smart IoT Posture Corrector and Hydration Assistant

A bidirectional IoT system comprising a wearable posture corrector and a desk display unit that alerts users to slouching and tracks hydration.

Originally published on CircuitDigest

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

ESP32-C3 Development Board with Berg Pins - Unsoldered Rs. 390.00
MPU6050 - Triple Axis Accelerometer + Gyroscope Module Rs. 438.00
3–6V R140 DC Motor (High-Speed DIY & Toy Motor) Rs. 49.00
10pcs - 220 ohm 1/4 W Resistor Set Rs. 39.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

This list includes a generic resistor set as a placeholder — it is not matched to the exact value or part number this circuit needs. The correct one is specified on the original source page linked above; check it before buying.

We don't carry yet: Transistors (BC547 / 2N2222 / TIP / MOSFET)
Battery Charger Module TP4056
LiPo Battery
Enclosure / Box / Case

Browse all components

How It Works

The Core Posture system operates as a distributed, bidirectional IoT setup utilizing an ESP32-S3-Box-3 desktop display unit and an ESP32-C3 SuperMini wearable module communicating via the ESP-NOW framework. The wearable component integrates an MPU6050 accelerometer sensor to continuously monitor real-time spatial orientation and detect user slouching. When poor posture is identified, the ESP32-C3 triggers a coin vibration motor to provide immediate tactile feedback. Because microcontrollers cannot supply enough current directly to inductive loads like motors, a BC547 NPN transistor acts as a solid-state switch controlled through a 1k current-limiting base resistor. Power management is handled by a TP4056 charging module connected to a LiPo battery, ensuring safe recharging of the portable wearable unit. Meanwhile, the desktop ESP32-S3-Box-3 processes incoming telemetry data and renders graphical updates using the LVGL library to track hydration habits and posture metrics. Both microcontrollers are programmed via the Arduino IDE, combining local sensor processing, wireless node communication, and graphical user interface rendering into a cohesive health-monitoring architecture.

Why Build This

Develop practical competence in wireless sensor networks by linking wearable edge nodes to a centralized desktop dashboard using the lightweight ESP-NOW protocol.

Gain hands-on engineering experience integrating low-power analog switching circuits—such as using an NPN transistor and base resistor to drive a coin vibration motor from a microcontroller GPIO pin.

Implement embedded graphical user interfaces (GUIs) with the LVGL library on advanced microcontrollers like the ESP32-S3 for real-time personal health and ergonomics tracking.

Real-World Application

Office ergonomics, posture rehabilitation, and personal health monitoring for desk-bound workers.

Skills You'll Learn

Wireless mesh and peer-to-peer communication

I2C sensor interfacing

transistor-based load switching

battery power management

embedded GUI development

Safety Precautions

Ensure proper battery wiring and polarity when connecting the LiPo battery and TP4056 charging module to prevent short circuits.

Technology Tags

IOT

ESP-NOW

MPU6050

LVGL

WEARABLES

FREERTOS

WIRELESS COMMUNICATION

ACCELEROMETER

UI DESIGN

Frequently Asked Questions

Why is an NPN transistor needed to drive the coin vibration motor?

Microcontroller GPIO pins output limited current, which is insufficient to safely drive inductive loads like motors. The transistor acts as an electronic switch, allowing the ESP32-C3 to control the motor using a safe, low-current signal through the 1k resistor while drawing the necessary operating current directly from the power rail.

Can I use a standard USB cable to power both the wearable and desktop units?

The desktop ESP32-S3-Box-3 connects directly to USB for power and programming, but the wearable ESP32-C3 SuperMini relies on an independent LiPo battery managed by the TP4056 charging module to ensure it remains completely portable.

How do the wearable unit and the desktop unit communicate without a Wi-Fi router?

They utilize the ESP-NOW framework, which is a connectionless wireless communication protocol developed by Espressif that allows ESP32 devices to talk directly to each other over short ranges without needing an external access point.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

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