Use of Existing Rotor Structures for Power and Data Transfer

Blade electrical connections typically utilize conductive wires which are embedded within the composite blade structure, typically before the autoclave process. While it is possible to use these wires for sensor data and power connections, it is difficult to route wires to all points of interest on a helicopter blade. We present an approach for power and data transfer utilizing the existing blade materials and geometry as an electromagnetic waveguide. As opposed to open air wireless sensor communications, using the hollow portion of a carbon spar allows for more efficient transfer of power as well as increased communications bandwidth. Concept measurement results showed less than 8 dB insertion loss along a 13' blade section at 2.4 GHz. It was demonstrated that anisotropic carbon-graphite can be modeled as an isotropic material with an equivalent conductivity.