Inspired by a remote-controlled Radio Flyer tricycle in which Kermit pedaled around at Maker Faire New York 2018, Donald Bell wanted to create his own version that could bring similar magic to people who interact with it. It began with the same Radio Flyer tricycle as in the original video, except this one was modified a bit differently.
An overarching goal that Bell wanted to achieve was keeping the tricycle as stock as possible, which meant placing all of the electronics underneath the rear axle. Movement is provided by a single DC motor just below one of the wheels that connects via a timing belt for added safety. Meanwhile, the trike is able to steer thanks to a 24V high-torque servo motor that rotates to push a rod back and forth, thus turning the front fork to either side. Controlling all of these parts is an Arduino Uno that receives information from an RC receiver module.
Rather than using a more complicated electronic speed controller (ESC) or a fancy RC receiver, Bell instead opted for a basic one which generates a PWM signal on several of its output pins that changes based on the transmitter’s joystick position. Once the code had been loaded onto the Arduino and a battery connected, he finally added his partially homemade puppet that both grips the handlebars and pushes the front pedals on the wheel.
More details about this project can be found on Instructables and seen in the video below!