Concept Bytes’ coffee table tracks people and walks itself across a room when called

The term “mmWave” refers to radio waves with wavelengths on the millimeter scale. When it comes to wireless communications technology, like 5G, mmWave allows for very fast data transfer — though that comes at the expense of range. But mmWave technology also has some very useful sensing and scanning applications, which you may have experienced for yourself while going through airport security. The fellas at Concept Bytes employed mmWave sensing to make their coffee table track people.

Eight months ago, Concept Bytes posted a video showcasing their walking coffee table. It could move around on Strandbeest-inspired legs, which looks pretty amazing. They redesigned that coffee table in their most recent video and made it a lot more sophisticated. Part of that sophistication is the ability to locate people in the room and walk to them when called.

At first glance, the new table looks similar to the original. But it was engineered to be easier to build using 3D-printed parts, to contain hidden coolers, to operate by remote control, and to come when called.

The leg mechanisms are based on Giliam de Carpentier’s Carpentopod geometry, which resembles the work of Theo Jansen. But that mechanism was algorithmically optimized for very smooth motion with input from electric motors. 

The coffee table has two sets of those legs to enable tank-style steering. An Arduino Nano RP2040 Connect board controls their motors through H-bridge drives. Another Nano RP2040 Connect housed in the remote allows for control via Wi-Fi. The coffee table’s Arduino is able to detect the sound of clapping hands through its onboard microphone. That is a command to come to the clapper.

It finds the clapper using an AI-Thinker RD-03D mmWave sensor that works a bit like radar, but at relatively short distances (0.5 to 8 meters) and with very good precision. It is so precise that, upon hearing a clap, the table will walk directly to the clapper and stop immediately in front of them.