⚕️Enigma Robolox - Android & IoT focused Home Automation System

View on GitHub

🖥️ Abstract

Robolox is an IoT-enabled Android application tailored for elderly care environments. It integrates NodeMCU (ESP8266), GSM/CDMA modules, MQ-2 gas sensors, HC-SR04 ultrasonic sensors, and DHT-11 environmental sensors to provide real-time monitoring and control. The system supports voice-activated appliance control via Google Speech Recognition, emergency SMS-based alerts through SIM900a, and seamless data exchange using Retrofit and Volley libraries. Optimizations such as persistent HTTP connections, payload compression, and priority-based scheduling reduced latency to <1.2s and improved communication efficiency by ~30%. The project was funded by Janata Bank PLC, deployed in a local elderly care center, awarded 3rd Runner-Up at Engenius 2018, and later published in a peer-reviewed journal, titled “An Android Application and Speech Recognition-Based IoT-Enabled Deployment Using NodeMCU for Elderly Individuals.” 

Methodology 

• The MQ-2 gas sensor detects levels of LPG, propane, and hydrogen gases and sends this data to the Arduino Mega. If gas levels exceed the set threshold, the Arduino Mega triggers the SIM900a module to send an SMS to a designated phone. Upon receiving the SMS, the Robolox Android application alerts the user to take necessary action.

• The HC-SR04 sensor detects objects within a specified range and sends feedback to the Arduino Mega, which then sends an SMS alert through the SIM900a module. The Robolox app reads this SMS and triggers an alarm to notify the user of any unauthorized access.

• The Robolox Android app interface enables control of home appliances like fans, lights, servo motors, washing machines, and more, all connected to a Relay Module via the NodeMCU IoT platform (ESP8266). The Retrofit library facilitates HTTP POST requests to the NodeMCU’s web server for seamless control.

• Integrates Google Speech Recognition API to allow voice-activated control of home appliances.

• Reads real-time weather data, including temperature, humidity, and heat index, from the DHT-11 sensor and formats it as a JSON array.

• Facilitates end-to-end data exchange with the IoT platform’s web server (NodeMCU-ESP8266 MOD) using Volley.

• Stores contact details for local emergency services, such as police, fire, and hospitals, in an SQLite database.

• Triggers an alarm if the DHT-11 sensor detects a temperature exceeding the set threshold.

• Optimized speech-to-action response time to <1.2 seconds.

• Reduced HTTP POST delay using persistent connections (keep-alive), cutting overhead by ~30%.

• Applied payload compression and priority-based scheduling to ensure sub-second emergency alerts while batching less urgent data.

🖥️ Technologies

Android Forntend - Java , XML

Web Frontend - HTML, CSS3, JavaScript

Embedded System - C++

Backend - SQLite, RESTful API, Broadcast Receiver

Microcontrollers - ESP8266 (NodeMCU IoT Platform) , Arduino Mega

Sensors : MQ2, DHT-11, HC-SR04

Modules : SIM900a, Relay

IDE - Android Studio, Arduino IDE