New research from the Massachusetts Institute of Technology (MIT) should remind us of the power of low-cost, elegant simplicity in deploying the Internet of Things (IoT) at scale.
As impressive as technologies such as robotics and AI may be, such innovations are often reserved for those companies with equally impressive budgets. When we think of the Internet of Things, however, most people picture a world where even commonplace items are connected.
Yet if we are to see the IoT working at scale – connected cities filled with smart street lighting, traffic management, and waste or pollution monitoring, for example, or smart farms that report animal, soil, and crop conditions across dozens of locations – the core technology needs to be cheap to deploy and power, and easy to maintain.
Radio-frequency identification (RFID) tags go some way toward meeting this need. Passive variants don’t require batteries, instead collecting the little power they need from the radio waves that connect them. Yet, to date, they have largely been used to track the identity, state, and location of things like shipments or livestock.
Now they can do much more, according to MIT.
RFID tags that can sense
Now engineers at MIT have found a way to configure RFID tags to work as sensors. MIT’s Auto-ID Lab has revealed a new ultra-high-frequency RFID tag-sensor configuration that could enable the development of continuous, low-cost, reliable devices that detect harmful chemicals in the environment.
At present, the device has been used to sense spikes in glucose and wirelessly transmit this information, but MIT’s researchers are now tailoring the tag to detect chemicals in the atmosphere, such as carbon monoxide.
Sai Nithin Reddy Kantareddy, a graduate student in MIT’s Department of Mechanical Engineering, said: “People are looking toward more applications like sensing to get more value out of the existing RFID infrastructure.
Imagine creating thousands of these inexpensive RFID tag sensors which you can just slap onto the walls of an infrastructure or the surrounding objects to detect common gases, like carbon monoxide or ammonia, without needing an additional battery. You could deploy these cheaply, over a huge network.
Kantareddy developed the sensor with Rahul Bhattacharya, a research scientist in the group, and Sanjay Sarma, the Fred Fort Flowers and Daniel Fort Flowers Professor of Mechanical Engineering, and vice president of open learning at MIT.
While previous attempts to extend the application and value of RFID technology have focused on adapting a tag’s antenna to respond to environmental changes, Sarma’s team tailored the memory chip so that it switches between power modes when it detects external stimuli.
This avoids the flaws of antenna-centric designs, which are vulnerable to interference caused by radio waves bouncing off multiple surfaces, leading to false readings.
Magnetic 3D printing
Meanwhile, other MIT researchers have been developing magnetic 3D printed structures that can be precisely manipulated with magnetic fields, with the potential to be used in the remote control of biomedical devices.
As published in a nature paper, the cleverly-folding nets are printed with an electromagnet attached to the printer nozzle to orient tiny magnetic particles in the ink in the desired direction. The resulting shapes can then move, open, and close in surprisingly elaborate ways.
As impressive and mesmerising as the technology may be, it could have important applications in controlling blood supply, in-body monitoring, and the precise delivery of drugs to particular parts of the body – shown by its ability to wrap around pill-like objects and unravel in response to an external magnet.
Xuanhe Zhao, the Noyce Career Development Professor in MIT’s Department of Mechanical Engineering and Department of Civil and Environmental Engineering, said:
We think in biomedicine this technique will find promising applications. For example, we could put a structure around a blood vessel to control the pumping of blood, or use a magnet to guide a device through the GI tract to take images, extract tissue samples, clear a blockage, or deliver certain drugs to a specific location.