Home Automation with ESP32 Timing Guide

Audience: students ages 12-18, no prior electronics experience required.
Format: 4-hour camp session (same content runs morning and afternoon).
Goal: every student wires, codes, and takes home a working humidity-to-color display.
Two breaks: 15 min each.

0:00–0:20 — Welcome & Goal Demo

Demo the finished project, run the icebreaker, intro Techster. Don’t let students wire yet.

  • Show the finished project running; let the LED change as you hold the sensor
  • Icebreaker: “Name one thing in your home you wish was smarter.”
  • Introduce “Lansing Techster” as a curious co-builder
  • Point out the kit at each station — don’t let students start wiring yet

0:20–0:45 — What Is Home Automation?

Interactive slides: smart = sensors + logic + output. Today: DHT22 → ESP32 → RGB LED.

Slide-driven but interactive — ask, don’t lecture.

  • Real examples: smart thermostats, Philips Hue, motion lights, door locks
  • What makes something “smart”? sensors + logic + output
  • The three pieces of today’s project: sensor (DHT22) → brain (ESP32) → output (RGB LED)

0:45–1:10 — Meet the Hardware

Hand out and name the parts: breadboard, ESP32, DHT22, RGB LED, resistors. Safety: never wire while powered.

Students handle parts and follow along.

  • Breadboard anatomy: rows, columns, power rails, why no soldering
  • ESP32: USB port, GPIO pins, onboard LED (GPIO 2)
  • DHT22: the pins and why it needs power, ground, and data
  • RGB LED: four legs, common cathode, which leg is which
  • Resistors: why they matter, reading color bands (quick)
  • Safety rules: never wire while powered; check work before plugging in

1:10–1:45 — Build the Blink Circuit

PlatformIO upload; Serial shows “LED ON / LED OFF”. Milestone: onboard LED blinks for everyone.

  • Walk through PlatformIO: open project, platformio.ini, src/main.cpp
  • Upload together; watch Serial Monitor for “LED ON / LED OFF”
  • Common issues: wrong COM port, driver not installed, baud rate
  • Milestone: every student sees the onboard LED blinking before moving on

1:45–2:00 — Break (15 min)

2:00–2:30 — DHT22 Sensor

Wire DHT22 (DATA → GPIO 4, 10 kΩ pull-up). Read temp + humidity to Serial. Milestone: real numbers print.

Add the DHT22 to the existing breadboard. No RGB LED yet.

  • Wire: VCC → 3V3, GND → GND, DATA → GPIO 4, plus a 10 kΩ pull-up between DATA and 3V3. Leave NC unconnected.
  • Walk through the library setup in platformio.ini
  • Live-code reading temperature + humidity to the Serial Monitor
  • Milestone: every student sees real numbers printing
  • Discuss: what would you do with this data?

2:30–3:05 — RGB LED + Color Logic

Wire RGB (220 Ω → GPIO 18/19/23, cathode → GND). LEDC PWM + setColor(). Milestone: LED changes when a student breathes on the sensor.

Add the LED (three resistors, three GPIOs) and write the color mapping together.

  • Wire: R → 220 Ω → GPIO 18, G → 220 Ω → GPIO 19, B → 220 Ω → GPIO 23, cathode (longest leg) → GND
  • Introduce LEDC PWM (ledcSetup / ledcAttachPin / ledcWrite)
  • Test each channel alone first — the firmware’s startup self-test cycles R → G → B for exactly this
  • Introduce the humidity thresholds and write setColor(r, g, b) together
  • Milestone: LED changes color when a student breathes on the sensor

3:05–3:30 — Integration + Debugging

Combine the DHT22 read + color logic in one loop(). Watch for nan, wrong pins, cathode/anode mix-ups. Walk the room.

  • Combine the DHT22 read with the color logic in one loop()
  • Common bugs: wrong pins, cathode/anode confusion, library missing, DHT read returns nan
  • Walk the room — ask guiding questions, don’t fix bugs for students

3:30–3:40 — Break (10 min)

3:40–3:55 — Personalization

Each student customizes one thing; strugglers aim for a solid working build.

Each student customizes one thing:

  • Adjust the thresholds, add a slow fade, print a custom Serial message, or mix new colors
  • Students who struggle: focus on a solid working build — that’s the win

3:55–4:00 — Show & Tell + Wrap-Up

A few demos, home power tip (USB power bank), hand out reference cards.

  • A few students demo their project
  • How to keep it running at home (USB power bank)
  • Point to the Next Steps resources; hand out reference cards

Between sessions (~30 min turnaround)

Collect stray hardware, restock LEDs/resistors, reset demo station, quick debrief.

  • Collect stray hardware; restock blown LEDs and missing resistors
  • Reset the demo station
  • Quick debrief: what questions came up? adjust pacing for the afternoon group