UAV-Based Wireless Telemetry System for the Estimation of Ship Air Wake Patterns

This paper presents the development of a wireless instrumentation system for estimation of air turbulence patterns in real-time. The proposed system uses off-the-shelf RC helicopter flying in wind turbulent regions and uses the oscillations caused by wind gusts to measure turbulence. This paper presents the proposed system as a tool to measure off-board ship air wake patterns generated by a cruising naval patrol craft. Two aviation grade Inertial Navigation Systems (INS) with onboard filters are used in this system. These filters precisely measure the dynamics and the location of the helicopter with respect to the vessel. The data is then wirelessly transmitted to a base station on the vessel where Back Propagation neural networks are used to remove the effects of pilot inputs from vibrational data in real time to extract the oscillations caused by the turbulence alone. The system was tested in Chesapeake Bay in a wide range of wind conditions and the results are shown as air wake intensity patterns plotted on helicopter trajectory around the cruising vessel. The proposed system will be used for experimental validation of CFD models to predict ship air wakes.