Engineering development and certification testing of new Advanced Air Mobility (AAM) concepts will require measurement of rotor and propeller properties to validate predicted loads and assure operational safety of these systems. These AAM configurations employ multiple distributed rotors and propellers, driven by electric motors, presenting a measurement challenge if they are to be simultaneously monitored during a test program. While wireless RF telemetry provides a potential solution to this problem, issues with multipath and signal interference still limit the application of this technology to a few data channels. This effort will expand upon a customized optical telemetry system developed in support of extracting rotor-mounted sensors that provides synchronized burst transmission of data between optical transducers that come into alignment at least once every revolution of the rotor or propeller blade. Design modifications are suggested to make the unit, previously developed for helicopter main rotor use, applicable for installation on AAM vehicles with their smaller diameter rotors that rotate at higher rates. The units promise to make instrumentation for wind tunnel or flight test on these multi-rotor aircraft easier, with significantly reduced size, weight and power requirements over existing conventional techniques.
NASA applications would directly benefit from having access to a wider spectrum of available test data from rotating components, supporting both wind tunnel and flight test programs and furthering research on AAM aircraft as well as conventional rotorcraft. Installed optical telemetry hardware would avoid RF interference that plagues extensive use of RF wireless instrumentation systems.
Small form factor instrumentation with optical links to non-rotating surfaces could support a health and usage monitoring system, providing real-time rotating frame stresses, displacements, and other indicators of applied loading conditions. DoD applications could include wind tunnel and flight qualification testing, as well as support various research programs in aeromechanics modeling.