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The Rotational Tension Element Damper (RTED) uses a controlled tension line, backed by hydraulics, to damp large displacements in large structures. NASA built RTED prototypes that have been successfully tested on a 170-foot long wind turbine blade in test beds at the University of Maine. In this case, the RTED device damps the vibration of the large, tall turbine blades relative to a stationary anchor structure on the ground using a line and spring coupled to both the blade and the anchor, and controlled by a spool fitted with a one-way clutch. When force is applied, from heavy wind for example, the resulting movement of the tall structure triggers the necessary tension and compression cycles in the system to engage the rotating damper. The reaction force interferes with the rotation speed of the spool and disrupts and damps the vibration in the tall structure. The figure below shows test data for the RTED used on the wind turbine.

NASA's cryogenic isolation valve technology uses solenoid valves powered by direct current (DC) electrical energy to control and redirect the energy stored in the upstream line pressure. Powering the solenoid valves only requires a DC power source capable of supplying 22 watts that can be distributed and controlled in an on/off manner. By achieving actuation using only upstream line pressure and a 22-watt DC power source, many additional support systems that are required for electromechanical and pneumatic actuation are eliminated. This reduction of parts results in several benefits, including reduced footprint, weight, and potential cost of the valve in addition to lower energy consumption. NASA fabricated several operational prototype valves using this technology for a rocket company. The table below shows the results of tests performed on these valves under cryogenic conditions. Please contact the NASA MSFC Technology Transfer Office for additional information.

The tool developed through this work merges information from the electric propulsion system design phase with diagnostic tools. Information from the failure mode and effect analysis (FMEA) from the system design phase is embedded within a Bayesian network (BN). Each node in the network can represent either a fault, failure mode, root cause or effect, and the causal relationships between different elements are described through the connecting edges. This novel approach can help Fault Detection and Isolation (FDI), producing a framework capable of isolating the cause of sub-system level fault and degradation. This system: Identifies and quantifies the effects of the identified hazards, the severity and probability of their effects, their root cause, and the likelihood of each cause; Uses a Bayesian framework for fault detection and isolation (FDI); Based on the FDI output, estimates health of the faulty component and predicts the remaining useful life (RUL) by also performing uncertainty quantification (UQ); Identifies potential electric powertrain hazards and performs a functional hazard analysis (FHA) for unmanned aerial vehicles (UAVs)/Urban Air Mobility (UAM) vehicles. Despite being developed for and demonstrated with an application to an electric UAV, the methodology is generalized and can be implemented in other domains, ranging from manufacturing facilities to various autonomous vehicles.