The techers at the University of Waterloo have taken a huge step towards making smart devices that do not use batteries or require charging. They found a way to hack radio frequency identification (RFID) tags, the ubiquitous squiggly ribbons of metal with a tiny chip found in various objects, and give the devices the ability to sense the environment. As the example researchers demonstrated the wireless keypad clicker they invented by hacking RFID sensors with tiny push-button switches.
First, they removed the plastic cover from the RFID tag, then cut out a small section of the tag’s antenna with scissors, then attach a sensor across the cut bits of the antenna to complete the circuit. In their stock form, RFID tags provide only identification and location. It’s the hack the research team has done — cutting the tag’s antenna and placing a sensing device across it — that gives the tag the ability to sense its environment.
To give a tag eyes, the researchers hacked an RFID tag with a phototransistor, a tiny sensor that responds to different levels of light. By exposing the phototransistor to light, it changed the characteristics of the RFID’s antenna, which in turn caused a change in the signal going to the reader. They then developed an algorithm on the reader side that monitors change in the tag’s signal, which is how it senses light levels.
Where is the money?
Objects like those used by the techers have an IP address to connect to the Internet and are called Internet of Things (IoT) devices. The combined markets of the Internet of Things (IoT) will grow to about $520B in 2021, more than double the $235B spent in 2017. If the IoT device can operate without a battery, it reduces maintenance costs and allows the device to be placed in areas that are out of network. IoT devices are truly multifunctional, many of them are equipped with a variety of sensors, for example for detecting room temperature, light levels, sound, movement, etc., but one of the biggest problems is to make these devices stable without a battery. The invention of Canadian techers is a big step towards solving this problem.