Offline Voice Recognition Sensor for micro:bit, Arduino, ESP32 – I2C & UART

Gravity offline voice recognition sensor for micro:bit, Arduino and ESP32 with I2C and UART – voice control without an internet connection.

Gravity: Offline Voice Recognition Sensor

Overview

• Offline voice recognition module (no internet needed)

• Compatible with micro:bit, Arduino, and ESP32

• Supports both I2C and UART interfaces

• Ideal for voice-controlled DIY projects

Working Principle

• Microphone captures voice input

• Onboard processor analyzes and matches commands

• Outputs digital signal or serial data to microcontroller

• Works entirely offline, no cloud or internet required

Key Specifications

• Voltage: 3.3V 5V DC

• Current: ~2040 mA

• ustom commands

• Interfaces: UART / I2C / GPIO

• Number of Commands: 780 (depends on module and training)

• Response Time: ~200ms (fast recognition)

• Signal Output: High/Low digital pin or serial communication

Module Components

• MEMS microphone

• DSP / Voice recognition chip

• UART/I2C communication ports

• Control & status LEDs

Features

• Works offline no internet needed

• Customizable commands (trainable)

• Low power, compact design

• Supports multi-platform development

Applications

• Voice-controlled robots ojects

• Hands-free automation

• Educational STEM experiments

Usage Tips

• Use clean, noise-free environment for best accuracy

• Ensure proper power supply (stable 3.3V5V)

• Train module for custom voice commands

• Use short, distinct command words

Advantages

• Offline operation no privacy concerns

• Fast response (~200ms)

• Easy integration with Arduino, micro:bit, ESP32

• I2C & UART support flexible connectivity

Limitations

• Recognition depends on voice clarity

• Limited number of simultaneous commands