The Year of the Sensor

By Mark Roberti

At RFID Journal LIVE! 2015, a variety of low-cost RFID sensors will be introduced, giving end users the opportunity to better manage their environments.


For the past few years, I have been writing previews with some predictions about RFID Journal LIVE!, our annual conference and exhibition, which serves as something of a barometer for the state of the RFID industry. One thing that is already clear to me is that a big focus this year is on sensors, particularly low-cost passive sensors that will make it easy and cost-effective for companies, government organizations and others to monitor particular environments.

Smartrac will be showing off its moisture-sensing passive ultrahigh-frequency (UHF) RFID tag known as the Sensor DogBone, intended to launch innovation in moisture sensing. The company began shipping the tag, which complies with the EPC Gen 2 standard, to customers in February (see Smartrac’s New Passive Sensor DogBone Transmits Moisture Levels). Because it has no battery, the tag could be embedded in, say, the walls of buildings to report when moisture is present, and because it costs a fraction of what a wired sensor system would cost, the DogBone sensor tag could be placed everywhere.

Moisture can damage electronics, furniture, building materials and many other products. So a low-cost transponder that can be put in or on packaging to report when there is water present will be valuable to many industries.

Farsens will introduce battery-free RFID tags capable of monitoring the voltage levels of AC circuits, from 0 to 700 volts. The tags are also compliant with the UHF EPC standard and can be interrogated by off-the-self EPC RFID readers. The tag’s purpose is to enhance safety by reducing the need for human intervention in energy production and areas with heavy industrial machinery.

Phase IV Engineering has developed a battery-free RFID strain sensor, also based on the passive UHF EPC standard. Using only the RF field from the reader, the Phase IV SensTag strain sensor can detect a wide range of strain (up to +/- 9000 micro-strain). The company is also introducing a battery-assisted passive (BAP) version of the strain sensor that logs strain and temperature readings. The battery should last for 10 years, but even when it dies, the tag can still be read in a “read now” mode, so strain can be monitored for decades.

More than 200 of these SensTag strain sensors have been installed in the Northgate light rail tunnel being built in Seattle. The sensors are monitoring strain in the reinforced concrete tunnel liners that create the tunnel’s tube structure. During the fabrication of the liners, SensTags were welded into the rebar cage. Concrete was poured into the form and the entire SensTag strain sensor was permanently embedded more than an inch inside the concrete, but the transponders can still communicate with readers (see RFID Helps Contractors Measure Strain During Construction of Seattle Rail Tunnels).

These are just a sampling of the sensors that will be introduced at LIVE!, which will also feature other great products from companies worldwide (we have exhibitors coming in from 22 countries). We’re seeing interest from some new sectors, such as entertainment (concert organizers and the companies that print tickets) and steel manufacturers. Meanwhile, momentum continues to build in retail, and I think we will see more chains adopting RFID for all items, though it will take time to reach critical mass.

All in all, I predict a busy event with a lot of companies finding a variety of different solutions across a wide range of industries and applications.

Mark Roberti is the founder and editor of RFID Journal. If you would like to comment on this article, click on the link below. To read more of Mark’s opinions, visit the RFID Journal Blog, the Editor’s Note archive or RFID Connect.