Experimental Feasibility Analysis of Primary-Shadow Replication Scheme for I/O Tansmission Fault-Tolerance in Auto-Pilot Program of Small Scale UAV

This paper treats the Primary-Shadow Replication Scheme to embody fault-tolerant capability in Operation Flight Program (OFP) of small Unmanned Aerial Vehicles (UAV). The recent increase in UAV applications to various autonomous missions demands a highly reliable and safe OFP to cope with unexpected system faults. This paper proposes a modified application of Primary-Shadow TMO´s Replication (PSTR)[2]mechanism for quick detection and rectification of system failure with minimum intervention of human pilot. For this purpose the PSTR method is integrated into the Hardware-In-the-Loop Simulation (HILS) environment with a UAV model. Various failure modes in such as receiving UAV´s sensor data and sending calculated data to UAV´s actuator are simulated and tested to show the enhanced fault-tolerance nature of the OFP. The test results show that 96% of injected faults were successfully detected and recovered, and 94% of shadow OFP was successfully activated within given deadline.