surprise box

Surprise Box

November 2017
Designing Product Interactions

skills utilized:
+ microcontroller programming
+ laser cutting

Our team of four was tasked with creating a box that embodied the emotion of "surprise." The goal was not to focus on what was inside the box, but on the experience of opening it. Our group chose to have the box unexpectedly "come to life," having it stand up on four legs, spit out a key, then proceed to eat the key when the user inserts it.



Concept Generation

Taking inspiration from a funny video we watched about a box that would refuse to have its only switch turned on, we thought about how we might make a box that surprises users with its uselessness. We wanted the process of interacting with the box to result in nothing for the user, but not in a frustrating way. We thought about animatronics, puzzle boxes, video game items, and many other ways inanimate boxes come to have their own personality, and endear themselves to their users. Ultimately, we settled on a frog that would eat its own key, as if it were a fly placed on a frog's nose.


Prototyping & Construction


In the construction of the box, I took responsibility of the coding, wiring, and testing of the mechanisms inside the frog. Eight small servo motors and two green LEDs interfaced with a Teensy 3.2 to make the frog come to life. I took the approach of isolating the multiple systems, testing them individually, and then progressively adding them together to create the final product. I also utilized a small phototransistor and LED - mounted into the tongue as seen below - to sense when the key had been placed internally. Throughout the process, I was consistently checking in with teammates to make sure our components of the project would interface well together, and I constantly ran test runs of the system accounting for different lighting levels (which could interfere with the transistor), different mistakes in use (like the key falling out of the mouth hole).



After a long work session spent in construction, full-team troubleshooting, and then looking for a larger battery to solve power issues, the surprise box came to life in full for the first time! Our box surprised users with each interaction through its cycle, and elicited laughs, "aww"s,  and even a few gasps from users in class (see the video below!) and at the Northwestern Design Expo. Its looping program allowed it to continue to be used by everyone that approached it with minimal supervision needed. Overall, we were simply pleased that we made something that made others smile.