‘Internet of Things’: Safety’s Future?
The world is getting its first glimpse into how machine-to-machine wireless communication (the so-called "Internet of Things") could change the face of preventive maintenance for bridges and other structures.
The technology, called Weightless, made its public debut July 1 and 2 at the 5th Future of Wireless International Conference in Cambridge, England. The demonstration was later shown on a BBC news program.
The demonstration used a model bridge equipped with strain gauges that can sense displacement in a structure. The data are automatically communicated to a base station that can then warn the user of potential structural problems.
Weightless technology is a wireless standard for machine-to-machine (M2M) communication (sometimes called "the Internet of Things") that can use large numbers of small, low-cost sensors to transmit data over an air interface to a base station. The base station then processes the data based on the parameters measured by the sensors to determine if anything falls outside of its expected values.
The base station may be located several kilometers from the bridge, developers say.
The Weightless technology was demonstrated with a train crossing a model bridge equipped with the sensors. As the train crosses the bridge, the sensors relay information to Weightless terminals, which communicate with a Weightless base station.
The base station delivers the data to the user application, allowing a user to make an instant decision on the integrity of the bridge.
"This public demonstration at a premier international event marks a watershed moment for Weightless technology," Alan Scott, CEO of Argon Design, a Weightless Special Interest Group (SIG) company, said in an announcement.
With nearly 1,000 members worldwide, the Weightless SIG was established in November to manage development of the Weightless Standard and to make the technology available to developers worldwide.
What is Weightless?
Weightless was developed to support machine communications (rather than having people plug in the information) required for structural health monitoring systems. The technology operates in a wireless spectrum using the white space between television channels, which developers say is more efficient than Bluetooth, Wi-Fi, 3G or 4G.
Technology that enables machines to communicate with each other wirelessly has long been expected to have enormous global market potential.
However, the concept has always stumbled over "the difficulty in meeting all the requirements within the constraints of the available radio spectrum,” Weightless developers say.
Now, the availability of white space between television channels offers a free, “near-perfect” spectrum for the technology to operate. The terminal device costs less than $10 and can run for 10 years under normal conditions on two AA batteries, developers say..
Structural Health Monitoring
Structural Health Monitoring assesses multiple aspects of a structure's condition to increase safety and minimize failure. The monitoring captures data on the structure's condition to track its progress and detect new anomalies caused by mechanical factors (such as heavy loading) or physical or chemical factors (such as corrosion, salt and chloride, and freezing).
Permanent sensors installed in the system allow a real-time snapshot of the structure's condition that can be continuously monitored.
Sensors attached to infrastructure could facilitate real-time communication of potential structural integrity issues, such as corrosion and degradation.
The actual parameters monitored are application-specific and depend on several factors, including the type of structure, location, environmental conditions, and the types of loads and stresses. These parameters determine the range of sensor types to be mounted to the structure.
Developers have not said when the technology might be publicly available. Professor William Webb, CEO of the Weightless Special Interest Group, said the group is growing quickly, "and we expect to progressively see more applications developed over the course of the next few months."