One of the current limitations of electronic implantable devices is the need to include a battery or pass wires through the skin. Both of these approaches have safety issues, and wires limit where a device can move or be implanted, whereas batteries limit how small a device can be and come with a limited lifespan.
To address these issues, the MIT researchers have developed a way to wirelessly power an implantable device, using radiofrequency waves. This has been difficult to achieve so far, because the waves tend to dissipate during their journey through the body. However, by using a variety of antennas that emit radio waves at different frequencies, the researchers were able to make them combine and overlap so that they produce enough energy to power a device.
“We chose frequencies that are slightly different from each other, and in doing so, we know that at some point in time these are going to reach their highs at the same time. When they reach their highs at the same time, they are able to overcome the energy threshold needed to power the device,” said Fadel Adib, a researcher involved in the study. “Even though these tiny implantable devices have no batteries, we can now communicate with them from a distance outside the body. This opens up entirely new types of medical applications.”
The system has significant potential. From powering ingestible devices, such as smart drug delivery capsules and gastrointestinal sensors, to brain implants for deep brain stimulation or optogenetics, wireless power would provide a huge advantage.
The researchers are currently working to increase the range of the system. So far, they can achieve wireless power up to 10 cm deep in the body from antennas up to 1 meter away, but if the sensor is placed just under the skin, the range increases to 38 meters. “There’s currently a tradeoff between how deep you can go and how far you can go outside the body,” said Adib.
See a video about the system below.
The research will be presented at the Association for Computing Machinery Special Interest Group on Data Communication (SIGCOMM) conference in August.
You may be interested
Startups Race to Create Cancer Screens from DNAFrank - Mar 22, 2019
Silicon Valley is out for blood—and not just the rejuvenating blood of the young. Biomedical engineers are enthralled by the…
The Laser Maps Behind Cadillac’s Superb Self-Driving SkillsFrank - Mar 22, 2019
As you drive to Berkeley from San Francisco, the constrained lanes of the Bay Bridge touch down on land, then…
Avatar sequels ‘will be the most expensive movies of all time’Frank - Mar 21, 2019
Frank's source: http://www.independent.co.uk/arts-entertainment/films/news/avatar-sequels-most-expensive-movies-all-time-james-cameron-1-billion-production-release-date-a7978306.html