Champaign-Urbana Community Fab Lab
Champaign-Urbana Community Fab Lab

Arduino Walking Pom-Pom Bot Assignment – Nicholas Agate

     We began the second portion of the Arduino unit by experimenting with servos in class. We were shown the Sweep program by Barragan and how to tweak its variables. Then, we were instructed to get two servos running at the same time. Please see my in-class servos below.

     For my pom-pom bot, I took inspiration from the funky droids in Star Wars that sort of shuffle around on two legs. I began by sketching out a final product that I would want to create after my first iteration. I went online and looked for the Star Wars droid that I was thinking of, which turned out to be called a Gonk Droid, and made a sketch based off of it. Please see my drawing and the Star Wars droid that inspired it below.

     I had the layout of my final pom-pom bot, but I wanted to see if I could switch up the design for my first iteration. I started by cutting out a piece of cardboard that would form the bottom frame of this first bot, and I cut a rectangle in the middle where two servos could go. The idea was that the bot would drag itself across a surface with the two servo arms. I successfully created this bot to my vision, but it was difficult to get it to move properly. I modified Barragan’s Sweep code that was used in class and tried to tweak some variables to get the right movement. The result was a prototype that moved in a skewed, circular pattern. After working on this for a while, I moved onto the second iteration. Please see the first iteration below.

     Next I began work on the second iteration of this project. Because I wanted to create a droid that was similar to the one mentioned above, I reused the same base from the first iteration but, I flipped the servos to have their arms on the outside. I then created legs with popsicle sticks that I hot-glued and tied to the servo arms with rubber bands. This initially created a problem for me because I had changed the orientation of the servos, meaning that I had to adjust the code to align with the new orientation. I again used Barragan’s Sweep code and modified it to my needs. Please see the code and in-progress second iteration below.

     Finally, I finished the second iteration by adding a back, front, and top to the droid. I used cardboard and glued on paper that I designed with a sharpie and some markers. The end result was a droid that was able to scuffle from point A to point B. Please see the final bot below.

     Overall, I found this project to be fun and educational, because I had to consider aspects that I normally do not work with. For example, issues I had involved precise movement adjustments through code, getting the correct weight so that the droid could stand, and making sure that the legs were secured correctly to the servos. All of these gave me a hard time at one point or another, but after trying out different ideas and positions, I was able to get the droid to move in a straight line. If I were to do this project again, I would try to get the droid to take longer strides. The ones in Star Wars do shuffle in a similar way, but it would be interesting to see if I could make a faster droid. Thank you for reading.


Original code that was modified: Barragan’s Sweep program found in Arduino examples

Gonk Droid image: