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Home Assistant Smart Home System

In Production

First Principles IoT Engineering

A comprehensive smart home automation platform built from the ground up, featuring custom hardware integrations, reverse-engineered RF protocols, and sophisticated automation workflows. This project demonstrates the same first-principles approach applied to professional AI systems.

Home AssistantNode-REDMQTTTasmotaZigbee2MQTTESP32ESPHomeSDRCC1101ShellyPython
15+
smart devices
10+
automations
3
networks
4+
uptime years
Project Overview

Key Features

Custom garage door opener using reverse-engineered RF signals via SDR analysis
Humidity-triggered bathroom exhaust fan automation across multiple rooms
Tasmota-flashed IoT devices for enhanced local control and security
Zigbee mesh network with Aqara sensors, switches, and motion detectors
Real-time energy monitoring via GEO Trio smart meter integration
Washing machine completion notifications via power monitoring
Multi-zone lighting control with dimming capabilities

Practical Benefits

Energy Efficiency
Real-time consumption tracking enables informed energy decisions and identifies waste patterns
Security
Door/window sensors and motion detection provide comprehensive home monitoring
Convenience
Automated lighting and climate control eliminate manual switching across 3-story home
Reliability
Local-first architecture with Tasmota firmware ensures operation without cloud dependency
Technical Deep Dive

Technical Highlights

Custom Garage Door Integration

Novel Solution

Intercepted proprietary 433MHz RF signal using RTL-SDR software-defined radio, analyzed waveform patterns, reverse-engineered the protocol, then built a custom ESP32-based transmitter with CC1101 module integrated via ESPHome into Home Assistant. Required understanding of digital communication techniques, RF modulation, and embedded systems programming.

Tasmota Firmware Migration

Local Control

Flashed 10+ Sonoff devices with open-source Tasmota firmware, enabling local MQTT control, custom configurations, and freedom from manufacturer cloud services. Each device required careful GPIO mapping and MQTT topic configuration.

Node-RED Automation Engine

Smart Automation

Implemented sophisticated humidity-based bathroom fan control using Node-RED. System monitors temperature and humidity sensors (Sonoff TH16), calculates running averages, and triggers exhaust fans when threshold exceeded. Prevents moisture buildup and mold growth automatically.

Zigbee2MQTT Network

Mesh Network

Deployed Zigbee mesh network using Sonoff USB dongle and Zigbee2MQTT for low-latency local control. Network includes Aqara motion sensors, door/window sensors, wireless switches, blinds, and air quality monitors connected without proprietary hubs.

System Architecture

Core Components

Home Assistant OS on dedicated serverMosquitto MQTT BrokerNode-RED automation engineZigbee2MQTT coordinatorESPHome device manager

Data Flow

Sensors → MQTT → Home Assistant → Node-RED → Actuators. All traffic stays local on dedicated IoT VLAN for security isolation.

Integrations

GEO Trio smart meter (energy)
Aqara sensors (Zigbee)
Sonoff devices (WiFi/MQTT)
Shelly devices (WiFi)
iPhone notifications
Custom ESP32 (RF garage)
Device Inventory

WiFi/MQTT Devices

Sonoff TH16 (3x) - Temperature/humidity sensors in bathrooms
Sonoff Basic (3x) - Light switches and fan control
Avatar Smart Plugs (3x) - Power monitoring
Shelly 2PM - Dual relay for guest bathroom
Shelly Dimmer - Downstairs bathroom lighting
ESP32 + CC1101 - Custom garage door transmitter

Zigbee Mesh Network

Aqara Motion Sensor - Zach's room occupancy detection
Aqara Door Sensors (3x) - Front door and back doors
Aqara Wireless Switch (2x) - Bedroom controls
Aqara Blind Controller - Zach's room blinds
Aqara Bedroom Switches (2x) - Kids' room controls
Aqara Air Quality Sensor - Guest bathroom monitoring
First-Principles Lessons
1.Start with local control architecture - cloud dependencies create reliability and privacy risks
2.SDR analysis is invaluable for reverse-engineering proprietary protocols
3.MQTT provides flexible, decoupled communication between diverse devices
4.Dedicated IoT network isolation improves security posture
5.Open-source firmware (Tasmota) dramatically extends device capabilities
6.First-principles understanding of RF communication enables novel solutions
Enterprise Applications

Building Management Systems - Same architecture scales to commercial automation

Industrial IoT - MQTT patterns apply to factory sensor networks

Edge Computing - Local processing reduces latency and bandwidth requirements

Security Systems - Zigbee mesh provides reliable, tamper-resistant monitoring

The Builder Storyline Connection

This Home Assistant project exemplifies the same first-principles approach applied throughout my career. Rather than accepting black-box solutions, I reverse-engineered proprietary RF protocols, flashed custom firmware onto commercial hardware, and built integrations from scratch. These skills—understanding systems deeply before building on them—directly transfer to the AI systems I build today with the Personal AI Infrastructure and Risk-Agents platform.

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