Phase IV Engineering has successfully developed wireless, battery-free RFID sensors that were initially designed to improve NASA’s water reclamation on the International Space Station. Now these sensors can also be used for wind turbines.
Phase IV’s battery-free passive sensors can be used in predictive maintenance for turbines by keeping tabs on rotating equipment and watching for wear and potential failures before they happen. Essentially, they serve to modernize the way wind turbines are monitored, making the process safer and more efficient.
Here’s the story behind the development.
To gain more information about the reclamation process in space and how to improve it, NASA planned to monitor it by using wireless temperature sensors. But it costs NASA $40,000 to send a single gallon of water to the International Space Station. This cost could be greatly reduced if the Urine Processing Assembly (UPA), which reclaims drinking water from astronauts’ urine, is made more efficient.
Monitoring UPA is exceptionally complicated because it’s a vacuum-sealed, heat-jacket encased, spinning titanium drum full of corrosive liquid.
To meet this challenge, NASA turned to Phase IV Engineering of Boulder, CO to develop a breakthrough temperature sensor, eventually earning the company the “Most Innovative Use of RFID Technology” award at the annual RFID Journal Live expo.
The sensor system was previously considered impossible for a number of reasons:
1. battery-free, miniature RFID technology was formerly not compatible with metal.
2. The harsh, corrosive environment of the urine meant the sensor had to be extremely durable.
3. The UPA processes the urine through spinning, which means the sensor and reader only briefly have a direct, unobstructed wireless communication link.
“We designed the world’s first metal mount RFID wireless sensors — the first RFID sensors that can transmit effectively when mounted directly against metal,” explains Phase IV CEO Scott Dalgleish.
The battery-free temperature sensors are encapsulated in epoxy to resist the harsh chemicals of the UPA.
“Since the sensors are embedded deep inside the UPA, changing batteries is out of the question. Plus, if continuous readings are required, a battery-powered sensor would last only two to three weeks transmitting once every second. Our battery-free sensors last for decades while transmitting the same amount of data,” Dalgleish explains.
One of the most difficult parts of applying wireless sensors to spinning machines is that the sensor is in view of the reader for a very short time, making it hard to transmit data between the two. To address this problem, Phase IV installed multiple customized antennae on the inside and outside of the drum.
“The new sensors have already given us the first-ever temperature measurements from parts of the UPA that were previously considered inaccessible,” said Christopher Evans, an aerospace technologist leading the NASA team Phase IV worked with.
So how does this relate to wind turbines?
“The complex technology of spinning RFID wireless sensors has the potential to be applied to many fields that have rotating equipment, including wind turbines,” Dalgleish explained.
Spinning parts are among the most vital pieces of equipment in a wind turbine and are also some of the most susceptible to failure. Phase IV’s battery-free passive sensors can be used in predictive maintenance, continuously monitoring the spinning equipment for strain, pressure, and temperature to predict failures before they happen.
Utilizing wireless sensors means there is no hazard of cables being caught in rotating machinery and their ultra-high frequency means they can be used to transmit when mounted on metal—a major asset for sensors used on wind turbines.
The RFID sensors are ideal for application on blades, shafts, gearboxes, pumps, clutches, and generators of wind turbines.
These passive sensors have major implications for increased safety. The daily strain wind turbines endure can lead to wear that causes fires and other malfunctions that could be extremely dangerous.
Phase IV’s UHF RFID sensors can be used to prevent potential disasters. The wireless sensors can monitor both strain and temperature to predict a possible breakage, short circuit, or fire before it occurs, providing for enough time for the turbine to be shut down before hazardous accidents happen.
“Continuously monitoring wind turbines with wireless sensors can lead to significant savings both from avoiding maintenance costs that would occur if the rotating machinery failed and from improved process monitoring occurring in rotating equipment,” says Dalgleish.
Phase IV Engineering, Inc.
Filed Under: News, Sensors