Imagine a bottle of laundry detergent that can sense when you’re running low on the soap that can automatically connect to the internet to place an order for more.University of Washington researchers is the first to make this a reality by 3-D printing plastic objects and sensors that can collect useful data and communicate with other WiFi-connected devices of their own.With CAD models that the team is making available to the public, 3-D printing enthusiasts will be able to create objects out of commercially available plastics that can wirelessly communicate with other smart devices.

Scientists have developed new 3D-printed plastic objects that can hook up to Wi-Fi without the aid of any electronics or batteries.It means meaning household devices could get a lot smarter in the future without the need for any circuitry.The researchers found a way to 3D-print plastic objects that can absorb or reflect ambient WiFi signals and send data wirelessly to any WiFi receiver like a smartphone or router.The researchers “replaced some functions normally performed by electrical components with mechanical motion activated by springs, gears, switches and other parts that can be 3-D printed which borrowing from principles that allow battery-free watches to keep time.”The researchers found that those mechanical motions can trigger gears and springs that connect to an antenna along with the object.Possible use cases include an attachment for laundry detergent that can sense when soap is running low or a water sensor that notifies your smartphone when there is a leak.

This raises the question, 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.This motion-based attribute, in turn, allows the filament to connect more often.This finally ‘fuels’ the transmitted transitions to be more frequent.

You can simply put the movement that generates the transitions which allow 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. The digital aspect of the communication is borne by the tooth on the gear that connects with the mentioned filament for presenting the ubiquitous 1s and 0s. In scientific terms, these techniques are often perceived as a case of backscattering or reflecting waves.

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.This is 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. To achieve this, a team from the University of Washington built a system comprising a plastic switch, spring, gear, and antenna, which when activated with a press or other movement can absorb or reflect passing Wi-Fi signals in order to communicate.plastic objects

“Our goal was to create something that just comes out of your 3D printer at home and can send useful information to other devices,” says one of the researchers, electrical engineer Vikram Iyer.”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.”So a 3D-printed plastic uses an anemometer, for example, could measure wind speed because as it spins around more quickly, and the filament connects more often, the transmitted transitions get more frequent. A water flow meter would work in the same way.The scientists have been able to build similar mechanisms into switches, dials, and sliders.The movement generates the transitions and sends a simple signal over Wi-Fi, which could be a smartphone or another device.The presence of the tooth on a gear, connecting with the filament, taps out the 1s and 0s needed for digital communication.These kinds of techniques are known as backscattering or reflecting waves which in this case are the Wi-Fi signals.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 which almost like an invisible barcode that could be an identifier or instructions.

“It looks like a regular 3D printed object but there’s invisible information inside that can be read with your smartphone,” says one of the team, Justin Chan.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.For now, these 3D-printed gadgets are chunky and not yet ready for the masses, but in the future, they could be adapted for all sorts of purposes with so many gadgets in our homes now competing for Wi-Fi signal and electricity.It’s a simpler approach to getting more devices connected to the web and each other.

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 democratizing the creation of IoT-enabled objects that can communicate information seamlessly, everywhere and at any time,” write the scientists in their report.

Source: Science Alert