As the demand for unmanned aircraft systems (UAS) in a broad spectrum of commercial applications increases, regulatory authorities are examining how to safely integrate them into the national airspace system (NAS) without compromising safety or disrupting traditional airspace operations. For small UAS, several operational rules have been established under FAR Part 107 (e.g., do not operate beyond visual line-of-sight, do not fly within five miles of a commercial airport, do not fly above 400 ft above ground level). However, there is no current means of enforcing these rules with a high degree of assurance. This paper summarizes testing of an onboard system - Safeguard - designed to monitor and enforce conformance to a set of geospatial limitations defined prior to flight (e.g., geospatial stay-out or stay-in regions, and altitude constraints). Unlike typical geo-fencing or geo-limitation functions, Safeguard operates independently of the off-the-shelf UAS autopilot and is designed in a way that can be realized by a small set of verifiable functions to simplify compliance with existing standards for safety-critical systems (e.g., for spacecraft and manned commercial transportation aircraft). A framework is described that decouples the system from any other devices on the UAS as well as introduces complementary positioning source(s) for applications that require integrity and availability beyond what can be provided by the onboard Global Positioning System (GPS)-based navigation solution. This paper presents results of analyses of flight data collected during Safeguard testing since initial presentation of the design concept at the 35th DASC (2016) and further development and testing at the 36th DASC (2017). Over this timeframe, numerous flight tests were completed on multiple unmanned aircraft (including multi-rotor and fixed wing) with each performing various mission types (e.g., infrastructure inspections, low altitude flights over populated/urban areas, and extended visual line-of-sight flights). Findings will focus on quantifying the performance of the system in support of validation of assurance claims, as well as demonstration of advanced technology readiness level (TRL). Integration testing with NASA's UAS Traffic Management (UTM) service-oriented architecture was also demonstrated during many of these flights; allowing performance results for this capability to also be presented. The paper will conclude with plans for future research and development, including evaluating the use of alternate positioning systems, extending the conformance monitoring criteria, and embedding the functions into a more holistic runtime assurance system concept.
Safeguard
2018-09-01
695806 byte
Conference paper
Electronic Resource
English
Engineering Index Backfile | 1938
Engineering Index Backfile | 1938