The technology, say the researchers, can deliver 50 watts of power using magnetic fields. In addition to untethering phones and laptops, the technology could also power implanted medical devices and open new possibilities for mobile robotics in homes and manufacturing facilities.
The researchers say that they are also working on implementing the system in spaces that are smaller than room size - for example a toolbox that charges tools placed inside it.
“This really ups the power of the ubiquitous computing world," says study author Alanson Sample, U-M professor of computer science and engineering. "You could put a computer in anything without ever having to worry about charging or plugging in. There are a lot of clinical applications as well: today’s heart implants, for example, require a wire that runs from the pump through the body to an external power supply. This could eliminate that, reducing the risk of infection and improving patients’ quality of life.”
The researchers demonstrated the technology in a purpose-built aluminum test room measuring approximately 10 x 10 feet. They wirelessly powered lamps, fans, and cell phones that could draw current from anywhere in the room regardless of the placement of people and furniture.
The system, say the researchers, is a major improvement over previous attempts at wireless charging systems, which used potentially harmful microwave radiation or required devices to be placed on dedicated charging pads. Instead, it uses a conductive surface on room walls and a conductive pole to generate magnetic fields.
Devices harness the magnetic field with wire coils, which can be integrated into electronics like cell phones. According to the researchers, the system could easily be scaled up to larger structures like factories or warehouses while still meeting existing safety guidelines for exposure to electromagnetic fields.
“Something like this would be easiest to implement in new construction, but I think retrofits will be possible as well,” says Takuya Sasatani, a researcher at the