Motorizing a 20-Year-Old Lego Car

Installed an ESP32, a stepper motor, and LED headlights into a 20-year-old Lego car and built a custom iPad app to drive it. The wiring is a mess but it works.

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The Final Result [ Active ]

What's Actually Under the Hood

1. The Brains (ESP32-C3)

I took out the original lego seating and internals of the car and strapped in my custom protoboard (with an ESP32-C3 Super Mini). I coded it to run a custom Bluetooth (BLE) server that connects instantly to my iPad.

2. The Drivetrain (Stepper Motor Upgrade)

The original DC motor couldn't handle the weight of everything. I swapped it for a stepper motor hooked up to a ULN2003 driver board. It finally gave the car enough torque to push its own weight without stalling out.

3. The Native iOS App

I built a custom iOS app from scratch using SwiftUI and CoreBluetooth for real-time remote control. I also wired up a toggle for some yellow LED headlights, which is honestly my favorite part of the build.