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A custom-built robot lightens up the mood

The Droid Christian created with a heart lit up

As a technical solutions consultant at Google, Christian Gijtenbeek enjoys helping others with creative solutions to complex problems. While working from home this year, the Amsterdam-based Googler noticed a dilemma of his own. “It’s more challenging to interact with colleagues and clients without the non-verbal cues many of us are used to,” he says. “How do you effectively read body language in 2D?” 

His answer was to add an extra dimension, in the form of a 3D figurine, with a lot of help from his teenage daughter, Janine. "We decided to build a '”mood collector'” shaped like a large Android figurine," Christian says.

Christian and Janine with their robot

Christian, his daughter, Janine, and Droid, the light-up figurine they built together.

The wooden robot is about four feet (120 centimeters) tall with 640 individually addressable LEDs covering its body. He uses a small microcontroller to  signal each light to display a unique color. To show “moods,” Christian set up a Firebase website that gives people the option to share how their day is going by using a simple slider from a scale of 1 to 10.

The answers are translated to values stored in a Firebase realtime database. Any change to this data store triggers a light change to the robot. “It will briefly light up displaying the mood of the person voting,” Christian says, “which allows me to see a representation of how someone is doing in real time.”

It has shown her she can make almost anything she dreams of.

For example, if you move the slider all the way to the right and select “10” because you’re having an amazing day, Droid will automatically light up green. Then the robot’s lights will fade to a color that represents the aggregate mood of everyone who voted so far that day. And because the droid’s LEDs are equidistant, Christian can easily draw other patterns like logos, letters or even animations. 

The project serves as a conversation starter with colleagues, enables them to check in with themselves about how they’re feeling and even inspires them to use technology in a creative way to solve real problems. But the best part of building the bot was bonding with his daughter and teaching her important lessons. 

“I hoped she’d have fun, pick up a thing or two about technology and math and learn that it's OK to not get it right straight away,” Christian says. “For example, cutting 30 pieces of plywood to the wrong size because of a measuring mistake is not a failure, it’s a lesson for next time.”

Together they spent about three months working on this project, and Janine learned a lot about tech in the process. “It has shown her that she can make almost anything she dreams of. Tech is such a core part of our society, but it’s often hidden behind layers of abstraction,” Christian says. “Giving a basic understanding of the building blocks of this technology, and demystifying the ‘how’ can really help youngsters understand the possibilities and open up their horizons.” 


Interested in getting your kids involved in tech? Christian has some sage advice: “If your child shows some interest, just start. I had no idea how to use some of the tools, but there’s tons of information available and we figured it out together.”

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