Alexandra Greenspan



February 2015

Built With

Greta Gardner, Andy Mah


To create a clock-inspired chair that rotates over time the longer someone sits, pushing people to take more frequent breaks throughout the day.


Arduino, Adobe Illustrator, Laser Cutter

Clockwork is a chair that keeps track of how long you sit. Its seat rotates about 90 degrees over the course of three hours, ensuring that its occupant will have to take a break from sitting while the chair resets to its starting position.

There are many health risks that come with sitting for long stretches of time day after day, and Clockwork aims to create a fun an elegant way to combat these health issues. It’s time to take a stand and get up out of your seat! At least until it lets you sit at your desk again.

Clockwork Demo


It was a long process to figure out just how the chair design should reflect our timepiece inspiration.

One of the pages from Andy’s sketchbook

Greta and Andy focused mainly on the chair prototypes, while I focused on the electronics. Check out my arduino code. The hardest part was figuring out the method to keep track of time passing once the light sensor detected someone was sitting, and then rotate correctly as a result.

I set a variable which monitored the light level from the sensor (aka checked if someone was sitting), a variable to track the previous light level for my if-statements, and a constant variable to represent the mid-level of light. This ensured that in my if-statements I could figure out if someone had just started sitting or had been continuously sitting, and rotate the servo accordingly.

The circuit featured a light sensor and a servo motor

After making a prototype of the final design using ECO board and a jigsaw cutter, it was time to laser cut the chair and put it all together.

Cutting out the back of the chair and part of the motor mount

The motor mount to hold the servo which attaches to the seat

Time to attach it all together!

Final Chair Prototype

Angle view

Back view of the clock hands

Light sensor in the seat to sense occupancy

Our model approves of the chair!