Development of technologies for low-cost oceanographic unmanned aeronautical vehicles

Abstract

Oceanographic research vessels and buoys typically provide high-resolution, shortrange measurements at a high sample rate. Satellites provide wide-range, low-resolution measurements at a low sample rate. Therefore a gap exists in oceanographic observation capability for medium-range, high-resolution measurements at a high sample rate. An Unmanned Aeronautical Vehicle (UAV) could bridge this gap.
This research has provided a mission-ready autopilot and ground station for future oceanographic application by the National Oceanography Centre, Southampton. A sea landing is the only available option, which carries a low probability of UAV reuse and therefore requires a low-cost system. This and other application specific requirements led to the development of all autopilot and ground station software. This research provided novel contributions of pseudo-derivative feedback controllers for flight control, the generation of optimised matrix calculations for high-frequency aircraft state estimates on a low-powered processor and the use of a finite impulse response filter for reduced aliasing of transmitted flight data.
A novel in-flight method for autonomously optimising controller response has been developed and successfully demonstrated in realistic simulation and practical flight tests of a commercial model aircraft. This method does not require an experiencedoperator or known aircraft dynamics and provides a quantitative measurement of optimality.
Two novel path tracking algorithms have been presented. The first controls the derivative of heading rate to command an achievable trajectory. The second controls the aircraft's closing speed on the path by adjusting bank angle. The latter algorithm achieved a robust tracking performance under simulated high wind conditions and practical flight tests and is suitable for oceanographic UAV operation.

More information

Identifiers

Catalogue record

Export record