|Title||Downwash Detection and Avoidance with Small Quadrotor Helicopters|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Authors||Yeo, DW, Sydney, N, Paley, D, Sofge, D|
|Journal||Journal of Guidance, Control and Dynamics, AIAA,|
By using four independent rotors to provide lift and control moments, the quadrotor helicopter provides researchers with a small, mechanically simple and effective vertical-flight platform. Typically, the lift and resultant torque due to each rotor can be approximated with simple aerodynamic models. Although these models have proven to be adequate in low advance-ratio flight conditions, they cannot account for the flow conditions associated with high-speed flight or the presence of large disturbances such as wind gusts or downwash from nearby rotorcraft. Real-time measurements of the flow-field around a flying vehicle provide a description of the flight conditions that would otherwise be impossible with only inertial-based instruments. This paper introduces a pressure-probe flow measurement system developed for a small quadrotor. The design, fabrication and calibration of the instrumentation package are presented along with data from autonomous flight trials using motion-capture-based positioning data. As a demonstration of the capabilities afforded by onboard flow sensing, a strategy for avoiding the downwash of a neighboring rotorcraft is proposed and demonstrated.
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