After finishing his recent Binbot 9000, James Bruton noticed a serious problem: the robot can’t climb stairs. That is an issue when his home does, in fact, contain stairs. Bruton has plans to build a beverage delivery robot and didn’t want to make the same mistake again. So to test the concept, he developed this prototype stair-climbing robot.
This robot climbs stairs using an interesting series of mechanisms. It has three wheeled sections, and the first and third sections can lift up relative to the middle section. The front two sections have differential drive motors, while the rear section only has freewheeling omniwheels. A sliding lead weight on top helps the robot shift its center of gravity, so it can balance on whichever wheels it needs to at any given time. Finally, the rear section slides forward and backward on rails, so the robot can move forward as it moves up each step.
All of that movement requires a lot of motors and there are eight in total: four for the drive wheels, two for the lift screws, one for the sliding weight, and one for the sliding rear section. An Arduino Mega 2560 board controls all of those motors. It receives commands through an nRF24L01 radio transceiver module. Instead of using his universal remote as he usually does, Bruton created a custom controller just for this project. It also contains an Arduino Mega and an nRF24L01 transceiver, and has 10 buttons and a directional joystick. The joystick lets Bruton move the robot forward, backward, left, and right, while the buttons let him actuate the sliders and lift mechanisms.
As you can see in the video, this robot can climb stairs. But it is also quite slow and Bruton thinks it is overly complicated. For those reasons, he doesn’t plan to use the concept for his beverage delivery robot. But it is still fun to see the prototype in action.