Manner again in 2005, Jan obtained a LEGO 4511 prepare set as a Christmas present. That nifty little package is an electrical mannequin railroad, however with LEGO’s trademark blocky user-assembled twist. Jan performed with that prepare set for years, however finally he acquired older and it ended up in storage for a decade, just like the bittersweet starting of a Pixar film. Quick ahead to the current and Jan is all grown up with some maker abilities below his belt. With vacation cheer in his coronary heart, he utilized these abilities to give the LEGO 4511 prepare set a Christmas ESP32 improve.
Like most mannequin railroads, the unique LEGO 4511 prepare set labored by supplying DC energy to the prepare engine via the rails. One rail is constructive and the opposite is floor. The prepare engine has a DC motor that completes the circuit and the controller lets the conductor alter voltage, thereby rising or reducing velocity. To maneuver the prepare backwards, the controller reverses the polarity via the rails.
Jan’s improve fully alters that complete working precept. As a substitute of receiving energy via the rails, the upgraded prepare is self-contained. It carries its personal lithium battery pack to energy the unique DC motor and an ESP32-based NodeMCU improvement board controls that via a DRV8833 twin H-bridge drive. Jan paired the 18650 lithium battery with a battery administration system and a TP4054 charging module. A splash of WS2812B RGB LED lighting gave the prepare that coveted Christmas aptitude.
The person can management the prepare with their smartphone via a Bluetooth connection. That’s accomplished with a easy terminal app that sends JSON serial instructions. Jan additionally built-in a form of brick-based positioning system, so the prepare can cease at predetermined bodily places that set off a contact sensor. That lets the prepare robotically go away the bar station and transfer alongside till it reaches the thirsty buyer station, the place it might cease lengthy sufficient for folks to seize their photographs.
Jan wished this upgraded prepare to ship photographs, however discovered that their weight overloaded the small LEGO motor. Sooner or later, he plans to present the prepare extra oomph and extra energy to go together with that.
These challenges ought to give Jan an excuse to play together with his LEGO prepare set for at the very least one other vacation or two.
