In addition to our faux earthquake apocalypse, our sixth grade earthquake unit included a hands-on design project that put our students in the role of structural engineer. At her previous schools, Ms. Worthington has had students create structures out of straws, Popsicle sticks, paper and tape that were then subjected to her very scientific shaking of the desks. Here at Excel, we knew it was time to step up her game.
Without knowing how to do it or even really what I meant, I committed to creating an earthquake simulation table. Something more fair – it would shake each structure consistently the same way – but more importantly, something to really motivate our students into seeing this challenge as a serious, computational thinking powered competition.
After considering several options online, I landed on a design using a DC motor that cranks a wooden top back and forth along rails. The original inspiration comes from the US Department of Energy’s Jefferson Lab. Our modified version replaces the motor/top interface with 3D-printed components and leaves the circuitry powering the design exposed to curious minds. An early attempt to leverage an Arduino-powered servo didn’t give us enough speed to disturb even the weakest structures, but thanks to some quick thinking by (and many hours of weekend work from) our very own electronics expert Mr. Williams, the table was ready to go in the nick of time. The simulation table even featured three different speeds (based on adding and removing batteries through the use of large switches) to simulate different earthquake strengths.
Students leveraged all they had learned about earthquakes and good building design to create their own structures. Pyramid-shaped projects proved to be the strongest, though with enough tape there were plenty of less-conventional designs that withstood some serious shaking as well. Listen to a student describe her winning structure below!