Cool Arduino and robotics builds from around the internet — what people made, how they made it, and the parts behind it.
A $35 ESP32-CAM build that sends a photo of whoever is at your door straight to your phone, with no subscription and no cloud storage. Full parts list, the GPIO conflicts nobody warns you about, and why the power supply is the step that kills most builds.
The EEZYbotARM MK2 uses a parallel linkage to keep every servo bolted to the base, so the moving arm is nothing but plastic. Here is why that design works, and the three parts you actually need to get it running.
A line follower is the cheapest way to learn closed-loop control: five infrared eyes, two motors, and code that has to react faster than the robot moves. Here is the full parts list, the wiring that trips people up, and the logic that actually keeps it on the line.
A capacitive soil sensor, a relay, and a $16 pump kit are all it takes to keep four plants alive while you travel. Here’s how the classic build works — and the four details that decide whether it survives ten unattended days.
A PIR motion sensor, magnetic reed switches, a passive buzzer and a keypad — what each part actually does, the gotchas that make beginner alarms misfire, and the state-machine logic that ties the whole thing together.
A six-dollar ESP8266 board, open-source firmware you flash from a browser, and no cloud account — this is how people are automating entire houses without a hub. Here is what the board can do, what it cannot, and how to get your first one clicking a relay.
Build the monitor before the watering rig. Here is the full parts list and wiring for an Arduino plant monitor, plus the sensor choice and calibration steps that decide whether it still works in three months.
The line follower is the classic first ‘real’ robot — autonomous, cheap, and simple enough to finish in a weekend. Here’s how the build works, and the pre-made chassis kit that makes it genuinely beginner-friendly.
The complete parts list, wiring diagram, and code walkthrough for a working Arduino weather station — temperature, humidity, and dew point in about an hour.
A $30 Arduino and DHT22 build that outperforms most consumer indoor weather stations. Here’s how it works and why it’s better.