Berkeley smart cap

Here’s a wearable for food packaging. Researchers at UC Berkeley have come up with a “smart” cap that can detect food that has gone bad. Working with scientists at Taiwan’s National Chiao Tung University, they created a cap that measures measures the resonant frequency of a tiny sample of milk from inside the carton. As the bacteria levels increase in the sample, the frequency drops, indicating that the milk is spoiled.

That’s interesting, to be sure, but the big story is not about just another biometric device, but rather how the device was designed and fabricated. The researchers claim that this is the first demonstration of using 3D printing to create basic electrical components: a resistor, inductor, and capacitor, as well as a working wireless sensor. They used a combination of polymer (which is a poor conductor and a good insulator) and wax to print their designs. They then melted the wax, leaving hollow structures that then could be filled with liquid metal to use as the electrical conductors. In this case, the scientists used silver.

The “smart” cap is actually a demonstration that this fabrication process can work. This could have significant implications for all sorts of wearable Health Tech devices. The 3D printing process makes it possible to create small devices with very fine detail, and the ability to create electrical components at the same time can save time and material, which can lower the production cost significantly. This same process could be used to create all sorts of wireless biometric sensors for a wide range of applications.