Low Cost RFID Torque and Tension Sensing Tag System

The FOSS technology revolutionizes fiber optic sensing by using its innovative algorithms to calculate a range of useful parameters—any and all of which can be monitored simultaneously and in real time. FOSS also couples these cutting-edge algorithms with a high-speed, low-cost processing platform and interrogator to create a single, robust, stand-alone instrumentation system. The system distributes thousands of sensors in a vast network—much like the human body's nervous system—that provides valuable information. How It Works Fiber Bragg grating (FBG) sensors are embedded in an optical fiber at intervals as small as 0.25 inches, which is then attached to or integrated into the structure. An innovative, low-cost, temperature-tuned distributed feedback (DFB) laser with no moving parts interrogates the FBG sensors as they respond to changes in optical wavelength resulting from stress or pressure on the structure, sending the data to a processing system. Unique algorithms correlate optical response to displacement data, calculating the shape and movement of the optical fiber (and, by extension, the structure) in real time, without affecting the structure's intrinsic properties. The system uses these data to calculate additional parameters, displaying parameters such as 2D and 3D shape/position, temperature, liquid level, stiffness, strength, pressure, stress, and operational loads. Why It Is Better FOSS monitors strain, stresses, structural instabilities, temperature distributions, and a plethora of other engineering measurements in real time with a single instrumentation system weighing less than 10 pounds. FOSS can also discern between liquid and gas states in a tank or other container, providing accurate measurements at 0.25-inch intervals. Adaptive spatial resolution features enable faster signal processing and precision measurement only when and where it is needed, saving time and resources. As a result, FOSS lends itself well to long-term bandwidth-limited monitoring of structures that experience few variations but could be vulnerable as anomalies occur (e.g., a bridge stressed by strong wind gusts or an earthquake). As a single example of the value FOSS can provide, consider oil and gas drilling applications. The FOSS technology could be incorporated into specialized drill heads to sense drill direction as well as temperature and pressure. Because FOSS accurately determines the drill shape, users can position the drill head exactly as needed. Temperature and pressure indicate the health of the drill. This type of strain and temperature monitoring could also be applied to sophisticated industrial bore scope usage in drilling and exploration. For more information about the full portfolio of FOSS technologies, see visit https://technology-afrc.ndc.nasa.gov/featurestory/fiber-optic-sensing

Pressure sensors play an important role in engine maintenance and monitoring systems by diagnosing problems before they happen. To capture the most accurate data, however, these sensors must be placed directly on an engine. In order to withstand extreme temperature and vibration, traditional pressure sensor technologies are bulky and complex, lacking the on-board control of microsystem technologies. Glenn's new capacitive pressure sensor system and packaging is the first of its kind to achieve high-temperature capability while maintaining miniaturization. This novel system consists of a Clapp-type oscillator that is fabricated on a high temperature alumina substrate. It comprises a silicon carbide (SiC) nitride pressure sensor, a metal-semiconductor field-effect transistor, and one or more chip resistors, wire-wound inductors, and SiC metal-insulator-metal (MIM) capacitors. The pressure sensor is located in the tank circuit of the oscillator so that a variation in pressure causes a change in capacitance, thus altering the resonant frequency of the sensing system. The chip resistors, inductors, and MIM capacitors have been characterized at temperature and operational frequency, and exhibit less than 5% variance in electrical performance. The system, which can be installed with a borescope plug adaptor in an on-wing operating engine, has been extensively tested and proven to operate reliably under extreme conditions. Its compact size, wireless capability, and ability to provide real-time in-situ data acquisition make this technology a game-changer in next-generation maintenance and monitoring systems.

In operation, this RFID-enabled patented technology reacts to a pressure change causing the passive tag to generate an electromagnetic field. The RFID pressure sensor/passive tag reacts to the electromagnetic field and responds by sending a signal to an interrogator. The interrogator receives the reflected signal, measures the returned signal strength indications ("RSSI") of the reflected signal and sends the RSSI measurements and identification of the responding RFID sensors to the processor to determine the pressure. Potential applications for this technology include remote patient mobility monitoring, robotic control systems, and pressure sensing gloves. Older devices may also be outfitted with these sensors to add pressure-monitoring functionality while avoiding the cost of a total system replacement.

Bolt fasteners can be used to provide control of the attachment force but they are not typically viewed as providing a locking attachment unless they are torqued to a prescribed percentage of the yield strength of the bolt. Adhesives are often used as an alternative means of locking threaded bolts, but adhesives are not well suited to inspection, removal or replacement, nor are they well suited for use in the space environment. Enter the Threaded Pin-Lock Retaining Ring system. It comprises a retaining ring, a structural component, the component being retained, and the pin-lock mechanism. The threaded interfaces allow for components being retained to be clamped between the retaining ring and the structural component. The pin-lock mechanism may be designed specifically for a given application and can be applied to both male and female threaded applications. The Threaded Pin-Lock Retaining Ring is configured for applications having precision torque requirements, and could be applied to any system with axially rotating components such as those commonly found in aerospace, automotive, cycling, energy sector, imaging, manufacturing, maritime, and robotics industries.

This novel technology builds upon a previously (NASA-developed) store-and-forward overlay architecture using COTS RFID protocols for BAP devices. It enables the range-extension and priority forwarding of critical sensor-collected data, even when an RFID interrogator is not in range. With this method, an RFID sensor maintains data queues of varying priority, maintaining at least one high-priority queue. When high-priority data is collected, the RFID sensor activates a BAP mode that enhances the effective range of the RFID link to the inter-rogator. After high-priority queues are cleared, BAP mode is deacti-vated to preserve onboard battery life and passive RFID operations resume for proximity-based data delivery. This technology may deliver the most value in applications where long battery lifetime and remote sensing/data collection are essential and when regularly scheduled data transfer may not be available or possible if the target is out of the normal coverage area. The RFID sensor tags described here can operate in a low to no-power mode and collect data until a trigger or threshold value is measured. At this time, the critical data can be transmitted from outside passive RFID coverage areas to the nearest interrogator. Although this technology was developed to enhance the effective range of CO2 sensors worn by astronauts aboard the International Space Station, it could find additional applications in food, pharma-ceutical, and other industries whose perishable and/or fragile goods rely on a stable climate throughout the transport and storage lifecycle.