Useless Robots

Robotics, Electronics, and Embedded Systems


The Basically Useless Gearbox

The Basically Useless Gearbox, or B.U.G. for short, is a robot that can dance, wander around aimlessly whilst avoiding obstacles, take pictures, play music, or follow your every command via an iPhone app.

Start – CompletionAugust 2016-August 2017 (periodic modification)
Languages & Technologies UsedATmega32u4 (Adafruit 32u4 Bluefruit), Bluetooth LE, Motors & Motor Drivers, Ultrasonic (obstacle avoidance), camera, C++/Arduino


Long long ago (summer of 2015), I was on the 3rd floor of an electronics mall in Taipei, Taiwan when I walk into a somewhat sketchy looking shop. To my delight, they were selling a whole bunch of cool stuff (Arduinos, Raspberry Pis, robots, etc.). After looking around a bit my eyes settled upon a plastic chassis (I had attempted hacking a really old motorized toy I had with my Arduino before with limited success). I bought the chassis with the intent of getting my Arduino to control it someday. 

Toward the end of summer of 2016 (about a year later), I was bored and decided to build a very small box like robot using the chassis that I had bought. Instead of using the full chassis, I decided just to glue the gearbox motors together with a piece a cardboard resulting in a much smaller size. 

I would often bring this contraption to school with me and a friend started calling it my little bug. Hence, as a joke, I named it B.U.G., the Basically Useless Gearbox..

Development & Challenges

One of the main challenges with B.U.G. is its size. I can only attach so many things to it before it becomes impractical. This made powering BUG a challenge. At first I used 4 triple As and tried a few different placements and battery packs, after a time it became clear 4 triple As and their 1000 mah capacity would give my 500ma power hungry robot very little battery life. I eventually switched to 4 double A batteries instead, and I plan to eventually switch to rechargeable lithium-ion batteries.


Not too many shortcomings in terms of living up to its name I’m afraid. However, if I were to choose something, I think that B.U.G.’s size is both a redeeming and restricting feature. It limits what I can add on to it while also challenging me to see what I can do on such a small platform.