|Harvesting energy from wireless signals to power 3D printed IoT device|
|Writer : upndown 3d public 2019-02-07 15:55:21Views : 13 Like : 0|
Feb 1, 2019 | By Cameron
The smart lock on a front door may not draw much power, but the Internet of Things (IoT) is expected to grow to 50 billion devices by 2020. Such devices include activity trackers, smart bulbs, every Alexa-compatible device, etc. Taken all together, that network of connected devices will pull a significant amount of electricity. Currently, they all have to be charged or left tethered to a power source. But new research out of King Abdullah University of Science and Technology (KAUST) may enable IoT devices to power themselves from energy captured from other wireless communication signals.
Specially-designed semiconductor diodes can convert radio frequencies into energy, but they’re usually tuned to a specific frequency, like 4G. Atif Shamim is a professor of electrical engineering and an expert on energy harvesting, and it occurred to him that advances in system-on-packages fabrication, where functional components like antenna are built into the housing of a device, could be applied to energy harvesting.
His team designed compact antennas that tune into a wide spectrum of wireless and mobile signals. “Asking one antenna to do the job of several others simultaneously is tricky,” stated Azamat Bakytbekov, the lead author of the paper. “You have to make sure the performance doesn’t drop at any one frequency point.”
For the prototype, fractal antennas were screen printed with silver onto 3D printed plastic squares that then connect together to form a cube covered in antennas. Shamim then collaborated with Khaled Salama’s team at KAUST to develop the diodes that convert the RF signals into electricity. The result is a cube that can harvest RF signals from all directions. Indeed, the prototype functions well according to co-author Thang Nguyen, who explained, “We saw the power gathered by the cube suddenly shoot up when a person nearby made a call. With the increase in mobile communication, this concept enables more and more radiofrequency energy to be harvested.”
Enough energy was pulled out of the air to power a small wireless sensor, which describes a large percentage of IoT devices. The team used a simple shape to demonstrate proof of concept because screen printing silver is easiest on flat surfaces, but there exist advanced 3D printers that could embed the antennas directly into the housing of a device that has a more complex shape. The next task is merging these technologies in a cost-effective way, but the reward will be a smartwatch that requires no battery because its housing is converting the invisible web of wireless signals all around us into energy used to post cat pictures on Facebook. Isn’t technology grand?
posted in 3ders.org