RT Journal Article
SR Electronic
T1 Air data fault detection and isolation for small UAS using integrity monitoring framework
JF NAVIGATION: Journal of the Institute of Navigation
JO NAVIGATION
FD Institute of Navigation
SP 577
OP 600
DO 10.1002/navi.440
VO 68
IS 3
A1 Kerry Sun
A1 Demoz Gebre-Egziabher
YR 2021
UL https://navi.ion.org/content/68/3/577.abstract
AB A Fault Detection and Isolation (FDI) algorithm is developed to protect against Water-Blockage (WB) pitot tube failure in the safety-critical Air Data System (ADS) used on small Unmanned Aircraft Systems (UAS). The algorithm utilizes two identical Synthetic Air Data Systems (SADS) as the basis for state estimation. Each SADS works independently with a pitot tube while sharing an IMU and GNSS receiver. The fault detection is designed using the integrity monitoring framework, and the isolation is obtained via independent fault detection channels. The ADS requirements are established, and the WB failure mode is analyzed based on real faulty air data. A new residual-based test statistic is introduced, and the link among the test statistic, observability matrix, and Minimal Detectable Error (MDE) are examined. Finally, a flight data set with a known water-blockage fault signature is used to assess the algorithm’s performance in terms of the air data protection levels and alert limits.