Evaluation of an Advanced Instrumentation System for Helicopter Rotors

Abstract : A test was conducted on the Bell Helicopter High Accuracy Rotor Test Stand to evaluate a time division multiplexing system for a rotor environment. The test model was a standard UH-1 tail rotor with a 0.1-inch-thick glove wrapped around the surface for the installation of transducers. The objective of this program was to develop and test a method of obtaining numerous channels of transducer information from a rotating system using a small number of slip rings. The system multiplexed the signal in the rotating system and demultiplexed the signal in the stationary system. Aerodynamic data were measured to evaluate the instrumentation system. Comparisons were made between multiplexed and unmultiplexed signals and between measured data and theory.