Scientists at the University of Washington have contrived 3D-printed plastic objects that can connect to Wi-Fi, without the need for electronics and battery. And while it may seem like some hack brought on by technical wizardry, these plastic components simply relegate circuitry in favor of an incorporated system that can absorb or reflect passing Wi-Fi signals.
This built-in system comprises the ‘bells and whistles’ of a plastic switch, spring, gear, and antenna. And since we are talking about interacting with signals, this is complemented by a conductive filament composed of plastic and copper, which by the way is also 3D printed. Simply put, the filament plays its crucial role in connecting and disconnecting with a Wi-Fi antenna, thereby altering the signals. Vikram Iyer, who was one of the electrical engineers involved in the project, said –
Our goal was to create something that just comes out of your 3D printer at home and can send useful information to other devices. But the big challenge is how do you communicate wirelessly with Wi-Fi using only plastic? That’s something that no one has been able to do before.
This raises the question – beyond just novelty, how does a Wi-Fi connected plastic object (without circuits) has its application in the real world? Well, a simple example would pertain to a volume slider of a speaker that works without the need for cables and power source. In fact, the scientists exhibited a 3D-printed plastic anemometer which has the capacity to measure wind speeds because of its quick spins, and this motion-based attribute, in turn, allows the filament to connect more often, and this finally ‘fuels’ the transmitted transitions to be more frequent.
Simply put, it is the movement that generates the transitions, thus allowing the transmission of a simple signal over Wi-Fi. Such mechanisms were built into switches, dials, and sliders, thus ultimately paving the way for a non-circuit based object to ‘connect’ with a device via Wi-Fi. In that regard, the digital aspect of the communication is borne by the tooth on the gear that connects with the aforementioned filament for presenting the ubiquitous 1s and 0s. In scientific terms, these techniques are often perceived as a case of backscattering (or reflecting waves).
Interestingly enough, as the Science Alert article points out –
The team was also able to adapt the filament to work with iron filings instead of copper, enabling the encoding of information into a 3D-printed object – almost like an invisible barcode that could be an identifier or instructions [for devices like smartphones]. That’s because just about every smartphone out there comes with a magnetometer to help work out where in the world it is based on the Earth’s magnetic field. The same sensor is able to detect the pattern of 1s and 0s created by the iron filings and plastic.
Now, suffice it to say, given the nascent stage of the technology, the plastic objects with their incorporated systems are rather cumbersome. However, on the brighter side, with more precision and development, many of these components can be adapted for real-world applications, ranging from cable-free volume sliders to automatically refilling laundry bottles. As the researchers made it clear in their report –
This work is part of our long-term vision for democratising the creation of IoT-enabled objects that can communicate information seamlessly, everywhere and at anytime.
The study was presented at the SIGGRAPH Conference and Exhibition in Asia, while one can take a gander at the report here.