Accession Number:

AD1081332

Title:

Autonomous Soaring across Three Orders of Magnitude of Mass

Descriptive Note:

Technical Report,01 Dec 2017,31 Dec 2018

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC WASHINGTON United States

Report Date:

2019-08-02

Pagination or Media Count:

21.0

Abstract:

Autonomous soaring extracts energy from the environment to improve aircraft endurance. It does so by gaining altitude in the convective boundary layer. This technique has been tested on two aircraft that are three orders of magnitude apart in mass 0.410kg to 710kg, showing the techniques general applicability. Despite three orders of magnitude difference in weight, both aircraft showed successful closed-loop autonomous soaring guidance. In the smaller unmanned aircraft, the autopilot closed the guidance loop in the manned aircraft, the pilot closed the guidance loop using commands from a flight director application called Thermal Finder. Both aircraft showed similar autonomous soaring behaviors. In addition, the updraft sensing described in this report is unaffected by inclusion of a propulsion system using a few simple tuning parameters, thereby widening the methods general applicability to other aircraft. Autonomous soaring holds great potential to increase endurance and range or reduce fuel consumption of soaring aircraft.

Subject Categories:

  • Pilotless Aircraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE