Selective Appeal Blog

Projects in Home Automation and the Internet of Things
Hero image

Posts

Dual Sonar ESP32 Garage State Estimation

August 9, 2026 • 10 min read • Garage Doors

Dual Sonar ESP32 Garage State Estimation

An upgraded Garage133 with dual ultrasonic sensors per bay, and multi-observation Hidden Markov Models, reliably detects both car presence and door state.
Reliable ESP32 Garage State Detection: Filtering Sonar Noise with HMMs

March 21, 2026 • 9 min read • Garage Doors

Reliable ESP32 Garage State Detection: Filtering Sonar Noise with HMMs

Applying Hidden Markov Models (HMM) on an ESP32 to filter sonar noise and achieve reliable garage door state detection in Home Assistant.
Dough133 Control: Precision ESP32 PID and Feedforward Temperature Control

February 14, 2026 • 8 min read • Sourdough

Dough133 Control: Precision ESP32 PID and Feedforward Temperature Control

How to achieve sub-degree temperature control on an ESP32 using physical thermal modeling, feedforward prediction, and PID feedback loops.
Building a Modern ESP32 Web Interface with Svelte and AI

November 10, 2025 • 7 min read • Plant Watering

Building a Modern ESP32 Web Interface with Svelte and AI

Creating a responsive, self-hosted web interface for ESP32 microcontrollers using Svelte, PlatformIO, and AI coding assistance.
Improving Reliability for ESP32 Plant Watering Systems: Lessons from Plant133

November 3, 2025 • 5 min read • Plant Watering

Improving Reliability for ESP32 Plant Watering Systems: Lessons from Plant133

Diagnosing and fixing common failures in ESP32 plant watering projects: PCB design flaws, pump corrosion, and soil moisture sensor protection.
Improved PCB Stencil Alignment with 3D Printed Fixtures

October 25, 2025 • 3 min read • PCB Assembly

Improved PCB Stencil Alignment with 3D Printed Fixtures

Improving manual solder paste printing using a custom 3D-printed stencil alignment fixture to prevent smearing and speed up assembly.
More posts  

Projects

PCB Assembly

October 24, 2025 • 1 min read

PCB Assembly

Methods for hand assembly of PCB boards with SMT components.
Garden133

June 15, 2025 • 1 min read

Garden133

A system for monitoring soil moisture levels in the yard and garden.
Garage133

May 26, 2025 • 1 min read

Garage133

A DIY garage door automation system using ESP32, ultrasonic distance sensors, and relays, with Home Assistant integration.
Room133

May 26, 2025 • 1 min read

Room133

A DIY ESP32-based multi-sensor platform for Home Assistant.
Dough133

May 26, 2025 • 1 min read

Dough133

An intelligent heated enclosure for fermenting and proofing sourdough.
Plant133

May 26, 2025 • 2 min read

Plant133

A device that monitors and waters indoor plants.