Disney Research has developed a new method for transmitting power throughout a room wirelessly. This technology enables users to charge electronic devices seamlessly as if they were connected to a Wi-Fi hotspot. This eliminates the need for charging cradles and electrical cords.
The researchers call their method quasistatic cavity resonance (QSCR). They demonstrated its functionality inside a specially built 16 x 16 foot room at their lab. Near field standing magnetic waves that filled the interior of the room were safely generated, enabling several cellphones, fans and lights to be powered at the same time.
Alanson Sample, associate lab director & principal research scientist at Disney Research and leader of the lab’s Wireless Systems Group, explains that the new method will make it possible for electrical power to become as omnipresent as Wi-Fi. By eliminating the need to replace batteries and wires for charging, this could in turn enable new applications for robots and other mobile devices. Although only room scale wireless power has been demonstrated, there is no reason this couldn’t be scaled up to the size of a warehouse, or even down to the size of a toy chest.
Sample pointed out that wireless power transmission has been a long-standing technological dream. In the 1890s, celebrated inventor Nikola Tesla demonstrated a wireless lighting system and proposed a system for transmitting power to homes and factories over long distances. This though was however never executed. Most wireless power transmission today happen over very short distances, typically between devices and charging pads or stands.
The QSCR method induces electrical currents in the metalized walls, ceiling and floor of a room. These then generate uniform magnetic fields that saturate the interior of the room. This makes it possible for power to be transmitted to receiving coils efficiently. The coils work at the same resonant frequency as the magnetic fields. Potentially harmful electrical fields are isolated by channeling the induced currents in the structure through discrete capacitors.
Chabalko explained that their simulations show that it is possible to transmit 1.9 kilowatts of power while still staying within federal safety guidelines. This is enough power to charge 320 smart phones at the same time.
The 16 x 16 foot room used for the demonstration was built with aluminum walls, ceiling and floor, which were all bolted to an aluminum frame. A small gap was created in the copper pole that was placed in the center of the room and discrete capacitors were inserted into this gap.
Chabalko explained that the electromagnetic frequency of the structure is set by the capacitors, while they also serve to confine the electric fields. Devices that operate at that low frequency can receive power from almost anywhere in the room. At the same time, other objects in the room are unaffected, as the magnetic waves at that frequency don’t interact with everyday materials. Sample also pointed out that although the demonstration room was specially constructed, it should be possible to decrease the need for metalized walls, ceilings and floors in the future. It may even be possible to retrofit current structures with conductive paint or modular panels. By using numerous copper poles, larger spaces might be accommodated. This research continues Disney’s rich legacy of innovation by combining innovation and creativity, and leveraging technology to enhance the systems and tools of tomorrow.